Bump CC:T to 1.115.0

Closes #2099

.github/ISSUE_TEMPLATE/bug_report.yaml

@@ -1,6 +1,7 @@
 name: Bug report
 description: Report some misbehaviour in the mod
 labels: [ bug ]
+type: bug
 body:
 - type: dropdown
   id: mc-version
@@ -29,3 +30,5 @@ body:
       Description of the bug. Please include the following:
       - Logs: These will be located in the `logs/` directory of your Minecraft instance. This is always useful, even if it doesn't include errors, so please upload this!
       - Detailed reproduction steps: sometimes I can spot a bug pretty easily, but often it's much more obscure. The more information I have to help reproduce it, the quicker it'll get fixed.
+
+      ![A gif of burning text reading "Upload your logs!!!"](https://tweaked.cc/images/logs.gif)

.github/ISSUE_TEMPLATE/feature_request.md

@@ -2,6 +2,7 @@
 name: Feature request
 about: Suggest an idea or improvement
 labels: enhancement
+type: feature
 ---
 
 <!--

buildSrc/src/main/kotlin/cc/tweaked/gradle/CCTweakedExtension.kt

@@ -10,9 +10,7 @@ import org.gradle.api.GradleException
 import org.gradle.api.NamedDomainObjectProvider
 import org.gradle.api.Project
 import org.gradle.api.Task
-import org.gradle.api.artifacts.Dependency
 import org.gradle.api.plugins.JavaPluginExtension
-import org.gradle.api.provider.ListProperty
 import org.gradle.api.provider.Provider
 import org.gradle.api.provider.SetProperty
 import org.gradle.api.tasks.SourceSet
@@ -168,7 +166,7 @@ abstract class CCTweakedExtension(private val project: Project) {
             jacoco.applyTo(this)
 
             extensions.configure(JacocoTaskExtension::class.java) {
-	        includes = listOf("dan200.computercraft.*")
+                includes = listOf("dan200.computercraft.*")
                 excludes = listOf(
                     "dan200.computercraft.mixin.*", // Exclude mixins, as they're not executed at runtime.
                     "dan200.computercraft.shared.Capabilities$*", // Exclude capability tokens, as Forge rewrites them.

gradle.properties

@@ -10,7 +10,7 @@ kotlin.jvm.target.validation.mode=error
 
 # Mod properties
 isUnstable=false
-modVersion=1.114.3
+modVersion=1.115.0
 
 # Minecraft properties: We want to configure this here so we can read it in settings.gradle
 mcVersion=1.20.1

projects/common-api/src/main/java/dan200/computercraft/api/media/PrintoutContents.java

@@ -0,0 +1,46 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.api.media;
+
+import dan200.computercraft.impl.ComputerCraftAPIService;
+import net.minecraft.world.item.ItemStack;
+
+import javax.annotation.Nullable;
+import java.util.stream.Stream;
+
+/**
+ * The contents of a page (or book) created by a ComputerCraft printer.
+ *
+ * @since 1.115
+ */
+@Nullable
+public interface PrintoutContents {
+    /**
+     * Get the (possibly empty) title for this printout.
+     *
+     * @return The title of this printout.
+     */
+    String getTitle();
+
+    /**
+     * Get the text contents of this printout, as a sequence of lines.
+     * <p>
+     * The lines in the printout may include blank lines at the end of the document, as well as trailing spaces on each
+     * line.
+     *
+     * @return The text contents of this printout.
+     */
+    Stream<String> getTextLines();
+
+    /**
+     * Get the printout contents for a particular stack.
+     *
+     * @param stack The stack to get the contents for.
+     * @return The printout contents, or {@code null} if this is not a printout item.
+     */
+    static @Nullable PrintoutContents get(ItemStack stack) {
+        return ComputerCraftAPIService.get().getPrintoutContents(stack);
+    }
+}

projects/common-api/src/main/java/dan200/computercraft/api/network/wired/WiredElement.java

@@ -19,8 +19,8 @@ import dan200.computercraft.api.ComputerCraftAPI;
  */
 public interface WiredElement extends WiredSender {
     /**
-     * Called when objects on the network change. This may occur when network nodes are added or removed, or when
-     * peripherals change.
+     * Called when peripherals on the network change. This may occur when network nodes are added or removed, or when
+     * peripherals are attached or detached from a modem.
      *
      * @param change The change which occurred.
      * @see WiredNetworkChange

projects/common-api/src/main/java/dan200/computercraft/impl/ComputerCraftAPIService.java

@@ -12,6 +12,7 @@ import dan200.computercraft.api.filesystem.WritableMount;
 import dan200.computercraft.api.lua.GenericSource;
 import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.MediaProvider;
+import dan200.computercraft.api.media.PrintoutContents;
 import dan200.computercraft.api.network.PacketNetwork;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
@@ -75,6 +76,9 @@ public interface ComputerCraftAPIService {
 
     DetailRegistry<BlockReference> getBlockInWorldDetailRegistry();
 
+    @Nullable
+    PrintoutContents getPrintoutContents(ItemStack stack);
+
     final class Instance {
         static final @Nullable ComputerCraftAPIService INSTANCE;
         static final @Nullable Throwable ERROR;

projects/common/src/client/java/dan200/computercraft/client/gui/ClientInputHandler.java

@@ -10,10 +10,10 @@ import dan200.computercraft.shared.computer.menu.ComputerMenu;
 import dan200.computercraft.shared.network.server.ComputerActionServerMessage;
 import dan200.computercraft.shared.network.server.KeyEventServerMessage;
 import dan200.computercraft.shared.network.server.MouseEventServerMessage;
-import dan200.computercraft.shared.network.server.QueueEventServerMessage;
+import dan200.computercraft.shared.network.server.PasteEventComputerMessage;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 
-import javax.annotation.Nullable;
+import java.nio.ByteBuffer;
 
 /**
  * An {@link InputHandler} for use on the client.
@@ -27,6 +27,11 @@ public final class ClientInputHandler implements InputHandler {
         this.menu = menu;
     }
 
+    @Override
+    public void terminate() {
+        ClientNetworking.sendToServer(new ComputerActionServerMessage(menu, ComputerActionServerMessage.Action.TERMINATE));
+    }
+
     @Override
     public void turnOn() {
         ClientNetworking.sendToServer(new ComputerActionServerMessage(menu, ComputerActionServerMessage.Action.TURN_ON));
@@ -42,11 +47,6 @@ public final class ClientInputHandler implements InputHandler {
         ClientNetworking.sendToServer(new ComputerActionServerMessage(menu, ComputerActionServerMessage.Action.REBOOT));
     }
 
-    @Override
-    public void queueEvent(String event, @Nullable Object[] arguments) {
-        ClientNetworking.sendToServer(new QueueEventServerMessage(menu, event, arguments));
-    }
-
     @Override
     public void keyDown(int key, boolean repeat) {
         ClientNetworking.sendToServer(new KeyEventServerMessage(menu, repeat ? KeyEventServerMessage.Action.REPEAT : KeyEventServerMessage.Action.DOWN, key));
@@ -57,6 +57,16 @@ public final class ClientInputHandler implements InputHandler {
         ClientNetworking.sendToServer(new KeyEventServerMessage(menu, KeyEventServerMessage.Action.UP, key));
     }
 
+    @Override
+    public void charTyped(byte chr) {
+        ClientNetworking.sendToServer(new KeyEventServerMessage(menu, KeyEventServerMessage.Action.CHAR, chr));
+    }
+
+    @Override
+    public void paste(ByteBuffer contents) {
+        ClientNetworking.sendToServer(new PasteEventComputerMessage(menu, contents));
+    }
+
     @Override
     public void mouseClick(int button, int x, int y) {
         ClientNetworking.sendToServer(new MouseEventServerMessage(menu, MouseEventServerMessage.Action.CLICK, button, x, y));

projects/common/src/client/java/dan200/computercraft/client/gui/GuiSprites.java

@@ -32,10 +32,13 @@ public final class GuiSprites extends TextureAtlasHolder {
     public static final ComputerTextures COMPUTER_COMMAND = computer("command", false, true);
     public static final ComputerTextures COMPUTER_COLOUR = computer("colour", true, false);
 
+    public static final ResourceLocation TURTLE_NORMAL_SELECTED_SLOT = new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/sprites/turtle_normal_selected_slot");
+    public static final ResourceLocation TURTLE_ADVANCED_SELECTED_SLOT = new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/sprites/turtle_advanced_selected_slot");
+
     private static ButtonTextures button(String name) {
         return new ButtonTextures(
-            new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/buttons/" + name),
-            new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/buttons/" + name + "_hover")
+            new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/sprites/buttons/" + name),
+            new ResourceLocation(ComputerCraftAPI.MOD_ID, "gui/sprites/buttons/" + name + "_hover")
         );
     }
 

projects/common/src/client/java/dan200/computercraft/client/gui/TurtleScreen.java

@@ -54,9 +54,9 @@ public class TurtleScreen extends AbstractComputerScreen<TurtleMenu> {
         if (slot >= 0) {
             var slotX = slot % 4;
             var slotY = slot / 4;
-            graphics.blit(texture,
-                leftPos + TURTLE_START_X - 2 + slotX * 18, topPos + PLAYER_START_Y - 2 + slotY * 18, 0,
-                0, 217, 24, 24, FULL_TEX_SIZE, FULL_TEX_SIZE
+            graphics.blit(
+                leftPos + TURTLE_START_X - 2 + slotX * 18, topPos + PLAYER_START_Y - 2 + slotY * 18, 0, 22, 22,
+                GuiSprites.get(advanced ? GuiSprites.TURTLE_ADVANCED_SELECTED_SLOT : GuiSprites.TURTLE_NORMAL_SELECTED_SLOT)
             );
         }
 

projects/common/src/client/java/dan200/computercraft/client/gui/widgets/ComputerSidebar.java

@@ -55,7 +55,7 @@ public final class ComputerSidebar {
         add.accept(new DynamicImageButton(
             x, y, ICON_WIDTH, ICON_HEIGHT,
             GuiSprites.TERMINATE::get,
-            b -> input.queueEvent("terminate"),
+            b -> input.terminate(),
             new HintedMessage(
                 Component.translatable("gui.computercraft.tooltip.terminate"),
                 Component.translatable("gui.computercraft.tooltip.terminate.key")

projects/common/src/client/java/dan200/computercraft/client/gui/widgets/TerminalWidget.java

@@ -71,11 +71,8 @@ public class TerminalWidget extends AbstractWidget {
 
     @Override
     public boolean charTyped(char ch, int modifiers) {
-        if (ch >= 32 && ch <= 126 || ch >= 160 && ch <= 255) {
-            // Queue the char event for any printable chars in byte range
-            computer.queueEvent("char", new Object[]{ Character.toString(ch) });
-        }
-
+        var terminalChar = StringUtil.unicodeToTerminal(ch);
+        if (StringUtil.isTypableChar(terminalChar)) computer.charTyped((byte) terminalChar);
         return true;
     }
 
@@ -112,8 +109,8 @@ public class TerminalWidget extends AbstractWidget {
     }
 
     private void paste() {
-        var clipboard = StringUtil.normaliseClipboardString(Minecraft.getInstance().keyboardHandler.getClipboard());
-        if (!clipboard.isEmpty()) computer.queueEvent("paste", new Object[]{ clipboard });
+        var clipboard = StringUtil.getClipboardString(Minecraft.getInstance().keyboardHandler.getClipboard());
+        if (clipboard.remaining() > 0) computer.paste(clipboard);
     }
 
     @Override
@@ -222,7 +219,7 @@ public class TerminalWidget extends AbstractWidget {
 
     public void update() {
         if (terminateTimer >= 0 && terminateTimer < TERMINATE_TIME && (terminateTimer += 0.05f) > TERMINATE_TIME) {
-            computer.queueEvent("terminate");
+            computer.terminate();
         }
 
         if (shutdownTimer >= 0 && shutdownTimer < TERMINATE_TIME && (shutdownTimer += 0.05f) > TERMINATE_TIME) {

projects/common/src/client/java/dan200/computercraft/client/model/LecternPocketModel.java

@@ -0,0 +1,96 @@
+// SPDX-FileCopyrightText: 2024 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.client.model;
+
+import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.VertexConsumer;
+import dan200.computercraft.api.ComputerCraftAPI;
+import dan200.computercraft.client.pocket.PocketComputerData;
+import dan200.computercraft.client.render.CustomLecternRenderer;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.pocket.items.PocketComputerItem;
+import net.minecraft.client.model.geom.ModelPart;
+import net.minecraft.client.model.geom.PartPose;
+import net.minecraft.client.model.geom.builders.CubeListBuilder;
+import net.minecraft.client.model.geom.builders.MeshDefinition;
+import net.minecraft.client.renderer.LightTexture;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.resources.model.Material;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.util.FastColor;
+import net.minecraft.world.inventory.InventoryMenu;
+
+/**
+ * A model for {@linkplain PocketComputerItem pocket computers} placed on a lectern.
+ *
+ * @see CustomLecternRenderer
+ */
+public class LecternPocketModel {
+    public static final ResourceLocation TEXTURE_NORMAL = new ResourceLocation(ComputerCraftAPI.MOD_ID, "entity/pocket_computer_normal");
+    public static final ResourceLocation TEXTURE_ADVANCED = new ResourceLocation(ComputerCraftAPI.MOD_ID, "entity/pocket_computer_advanced");
+    public static final ResourceLocation TEXTURE_COLOUR = new ResourceLocation(ComputerCraftAPI.MOD_ID, "entity/pocket_computer_colour");
+    public static final ResourceLocation TEXTURE_FRAME = new ResourceLocation(ComputerCraftAPI.MOD_ID, "entity/pocket_computer_frame");
+    public static final ResourceLocation TEXTURE_LIGHT = new ResourceLocation(ComputerCraftAPI.MOD_ID, "entity/pocket_computer_light");
+
+    private static final Material MATERIAL_NORMAL = new Material(InventoryMenu.BLOCK_ATLAS, TEXTURE_NORMAL);
+    private static final Material MATERIAL_ADVANCED = new Material(InventoryMenu.BLOCK_ATLAS, TEXTURE_ADVANCED);
+    private static final Material MATERIAL_COLOUR = new Material(InventoryMenu.BLOCK_ATLAS, TEXTURE_COLOUR);
+    private static final Material MATERIAL_FRAME = new Material(InventoryMenu.BLOCK_ATLAS, TEXTURE_FRAME);
+    private static final Material MATERIAL_LIGHT = new Material(InventoryMenu.BLOCK_ATLAS, TEXTURE_LIGHT);
+
+    // The size of the terminal within the model.
+    public static final float TERM_WIDTH = 12.0f / 32.0f;
+    public static final float TERM_HEIGHT = 14.0f / 32.0f;
+
+    // The size of the texture. The texture is 36x36, but is at 2x resolution.
+    private static final int TEXTURE_WIDTH = 36 / 2;
+    private static final int TEXTURE_HEIGHT = 36 / 2;
+
+    private final ModelPart root;
+
+    public LecternPocketModel() {
+        root = buildPages();
+    }
+
+    private static ModelPart buildPages() {
+        var mesh = new MeshDefinition();
+        var parts = mesh.getRoot();
+        parts.addOrReplaceChild(
+            "root",
+            CubeListBuilder.create().texOffs(0, 0).addBox(0f, -5.0f, -4.0f, 1f, 10.0f, 8.0f),
+            PartPose.ZERO
+        );
+        return mesh.getRoot().bake(TEXTURE_WIDTH, TEXTURE_HEIGHT);
+    }
+
+    private void render(PoseStack poseStack, VertexConsumer buffer, int packedLight, int packedOverlay, int colour) {
+        int red = FastColor.ARGB32.red(colour), green = FastColor.ARGB32.green(colour), blue = FastColor.ARGB32.blue(colour), alpha = FastColor.ARGB32.alpha(colour);
+        root.render(poseStack, buffer, packedLight, packedOverlay, red / 255.0f, green / 255.0f, blue / 255.0f, alpha / 255.0f);
+    }
+
+    /**
+     * Render the pocket computer model.
+     *
+     * @param poseStack     The current pose stack.
+     * @param bufferSource  The buffer source to draw to.
+     * @param packedLight   The current light level.
+     * @param packedOverlay The overlay texture (used for entity hurt animation).
+     * @param family        The computer family.
+     * @param frameColour   The pocket computer's {@linkplain PocketComputerItem#getColour(ItemStack) colour}.
+     * @param lightColour   The pocket computer's {@linkplain PocketComputerData#getLightState() light colour}.
+     */
+    public void render(PoseStack poseStack, MultiBufferSource bufferSource, int packedLight, int packedOverlay, ComputerFamily family, int frameColour, int lightColour) {
+        if (frameColour != -1) {
+            root.render(poseStack, MATERIAL_FRAME.buffer(bufferSource, RenderType::entityCutout), packedLight, packedOverlay, 1, 1, 1, 1);
+            render(poseStack, MATERIAL_COLOUR.buffer(bufferSource, RenderType::entityCutout), packedLight, packedOverlay, frameColour);
+        } else {
+            var buffer = (family == ComputerFamily.ADVANCED ? MATERIAL_ADVANCED : MATERIAL_NORMAL).buffer(bufferSource, RenderType::entityCutout);
+            root.render(poseStack, buffer, packedLight, packedOverlay, 1, 1, 1, 1);
+        }
+
+        render(poseStack, MATERIAL_LIGHT.buffer(bufferSource, RenderType::entityCutout), LightTexture.FULL_BRIGHT, packedOverlay, lightColour);
+    }
+}

projects/common/src/client/java/dan200/computercraft/client/render/CustomLecternRenderer.java

@@ -6,15 +6,28 @@ package dan200.computercraft.client.render;
 
 import com.mojang.blaze3d.vertex.PoseStack;
 import com.mojang.math.Axis;
+import dan200.computercraft.client.model.LecternPocketModel;
 import dan200.computercraft.client.model.LecternPrintoutModel;
+import dan200.computercraft.client.pocket.ClientPocketComputers;
+import dan200.computercraft.client.render.text.FixedWidthFontRenderer;
+import dan200.computercraft.core.terminal.Terminal;
+import dan200.computercraft.core.util.Colour;
 import dan200.computercraft.shared.lectern.CustomLecternBlockEntity;
 import dan200.computercraft.shared.media.items.PrintoutItem;
+import dan200.computercraft.shared.pocket.items.PocketComputerItem;
+import dan200.computercraft.shared.util.ARGB32;
 import net.minecraft.client.renderer.MultiBufferSource;
 import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.renderer.blockentity.BlockEntityRenderDispatcher;
 import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
 import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
 import net.minecraft.client.renderer.blockentity.LecternRenderer;
 import net.minecraft.world.level.block.LecternBlock;
+import net.minecraft.world.phys.Vec3;
+
+import static dan200.computercraft.client.render.ComputerBorderRenderer.MARGIN;
+import static dan200.computercraft.client.render.text.FixedWidthFontRenderer.FONT_HEIGHT;
+import static dan200.computercraft.client.render.text.FixedWidthFontRenderer.FONT_WIDTH;
 
 /**
  * A block entity renderer for our {@linkplain CustomLecternBlockEntity lectern}.
@@ -22,10 +35,17 @@ import net.minecraft.world.level.block.LecternBlock;
  * This largely follows {@link LecternRenderer}, but with support for multiple types of item.
  */
 public class CustomLecternRenderer implements BlockEntityRenderer<CustomLecternBlockEntity> {
+    private static final int POCKET_TERMINAL_RENDER_DISTANCE = 32;
+
+    private final BlockEntityRenderDispatcher berDispatcher;
     private final LecternPrintoutModel printoutModel;
+    private final LecternPocketModel pocketModel;
 
     public CustomLecternRenderer(BlockEntityRendererProvider.Context context) {
+        berDispatcher = context.getBlockEntityRenderDispatcher();
+
         printoutModel = new LecternPrintoutModel();
+        pocketModel = new LecternPocketModel();
     }
 
     @Override
@@ -44,8 +64,46 @@ public class CustomLecternRenderer implements BlockEntityRenderer<CustomLecternB
             } else {
                 printoutModel.renderPages(poseStack, vertexConsumer, packedLight, packedOverlay, PrintoutItem.getPageCount(item));
             }
+        } else if (item.getItem() instanceof PocketComputerItem pocket) {
+            var computer = ClientPocketComputers.get(item);
+
+            pocketModel.render(
+                poseStack, buffer, packedLight, packedOverlay, pocket.getFamily(), pocket.getColour(item),
+                ARGB32.opaque(computer == null || computer.getLightState() == -1 ? Colour.BLACK.getHex() : computer.getLightState())
+            );
+
+            // Jiggle the terminal about a bit, so (0, 0) is in the top left of the model's terminal hole.
+            poseStack.mulPose(Axis.YP.rotationDegrees(90f));
+            poseStack.translate(-0.5 * LecternPocketModel.TERM_WIDTH, 0.5 * LecternPocketModel.TERM_HEIGHT + 1f / 32.0f, 1 / 16.0f);
+            poseStack.mulPose(Axis.XP.rotationDegrees(180));
+
+            // Either render the terminal or a black screen, depending on how close we are.
+            var terminal = computer == null ? null : computer.getTerminal();
+            var quadEmitter = FixedWidthFontRenderer.toVertexConsumer(poseStack, buffer.getBuffer(RenderTypes.TERMINAL));
+            if (terminal != null && Vec3.atCenterOf(lectern.getBlockPos()).closerThan(berDispatcher.camera.getPosition(), POCKET_TERMINAL_RENDER_DISTANCE)) {
+                renderPocketTerminal(poseStack, quadEmitter, terminal);
+            } else {
+                FixedWidthFontRenderer.drawEmptyTerminal(quadEmitter, 0, 0, LecternPocketModel.TERM_WIDTH, LecternPocketModel.TERM_HEIGHT);
+            }
         }
 
         poseStack.popPose();
     }
+
+    private static void renderPocketTerminal(PoseStack poseStack, FixedWidthFontRenderer.QuadEmitter quadEmitter, Terminal terminal) {
+        var width = terminal.getWidth() * FONT_WIDTH;
+        var height = terminal.getHeight() * FONT_HEIGHT;
+
+        // Scale the terminal down to fit in the available space.
+        var scaleX = LecternPocketModel.TERM_WIDTH / (width + MARGIN * 2);
+        var scaleY = LecternPocketModel.TERM_HEIGHT / (height + MARGIN * 2);
+        var scale = Math.min(scaleX, scaleY);
+        poseStack.scale(scale, scale, -1.0f);
+
+        // Convert the model dimensions to terminal space, then find out how large the margin should be.
+        var marginX = ((LecternPocketModel.TERM_WIDTH / scale) - width) / 2;
+        var marginY = ((LecternPocketModel.TERM_HEIGHT / scale) - height) / 2;
+
+        FixedWidthFontRenderer.drawTerminal(quadEmitter, marginX, marginY, terminal, marginY, marginY, marginX, marginX);
+    }
 }

projects/common/src/client/java/dan200/computercraft/client/render/PocketItemRenderer.java

@@ -38,8 +38,8 @@ public final class PocketItemRenderer extends ItemMapLikeRenderer {
 
         int termWidth, termHeight;
         if (terminal == null) {
-            termWidth = Config.pocketTermWidth;
-            termHeight = Config.pocketTermHeight;
+            termWidth = Config.DEFAULT_POCKET_TERM_WIDTH;
+            termHeight = Config.DEFAULT_POCKET_TERM_HEIGHT;
         } else {
             termWidth = terminal.getWidth();
             termHeight = terminal.getHeight();

projects/common/src/client/java/dan200/computercraft/client/render/text/FixedWidthFontRenderer.java

@@ -43,7 +43,7 @@ public final class FixedWidthFontRenderer {
     static final float BACKGROUND_END = (WIDTH - 4.0f) / WIDTH;
 
     private static final int BLACK = FastColor.ARGB32.color(255, byteColour(Colour.BLACK.getR()), byteColour(Colour.BLACK.getR()), byteColour(Colour.BLACK.getR()));
-    private static final float Z_OFFSET = 1e-3f;
+    private static final float Z_OFFSET = 1e-4f;
 
     private FixedWidthFontRenderer() {
     }

projects/common/src/datagen/java/dan200/computercraft/data/DataProviders.java

@@ -6,6 +6,7 @@ package dan200.computercraft.data;
 
 import com.mojang.serialization.Codec;
 import dan200.computercraft.client.gui.GuiSprites;
+import dan200.computercraft.client.model.LecternPocketModel;
 import dan200.computercraft.client.model.LecternPrintoutModel;
 import dan200.computercraft.shared.turtle.inventory.UpgradeSlot;
 import net.minecraft.client.renderer.texture.atlas.SpriteSource;
@@ -54,9 +55,12 @@ public final class DataProviders {
             out.accept(new ResourceLocation("blocks"), makeSprites(Stream.of(
                 UpgradeSlot.LEFT_UPGRADE,
                 UpgradeSlot.RIGHT_UPGRADE,
-                LecternPrintoutModel.TEXTURE
+                LecternPrintoutModel.TEXTURE,
+                LecternPocketModel.TEXTURE_NORMAL, LecternPocketModel.TEXTURE_ADVANCED,
+                LecternPocketModel.TEXTURE_COLOUR, LecternPocketModel.TEXTURE_FRAME, LecternPocketModel.TEXTURE_LIGHT
             )));
             out.accept(GuiSprites.SPRITE_SHEET, makeSprites(
+                Stream.of(GuiSprites.TURTLE_NORMAL_SELECTED_SLOT, GuiSprites.TURTLE_ADVANCED_SELECTED_SLOT),
                 // Buttons
                 GuiSprites.TURNED_OFF.textures(),
                 GuiSprites.TURNED_ON.textures(),

projects/common/src/generated/resources/assets/computercraft/atlases/gui.json

@@ -1,11 +1,13 @@
 {
   "sources": [
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/turned_off"},
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/turned_off_hover"},
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/turned_on"},
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/turned_on_hover"},
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/terminate"},
-    {"type": "minecraft:single", "resource": "computercraft:gui/buttons/terminate_hover"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/turtle_normal_selected_slot"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/turtle_advanced_selected_slot"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/turned_off"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/turned_off_hover"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/turned_on"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/turned_on_hover"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/terminate"},
+    {"type": "minecraft:single", "resource": "computercraft:gui/sprites/buttons/terminate_hover"},
     {"type": "minecraft:single", "resource": "computercraft:gui/border_normal"},
     {"type": "minecraft:single", "resource": "computercraft:gui/pocket_bottom_normal"},
     {"type": "minecraft:single", "resource": "computercraft:gui/sidebar_normal"},

projects/common/src/generated/resources/assets/minecraft/atlases/blocks.json

@@ -2,6 +2,11 @@
   "sources": [
     {"type": "minecraft:single", "resource": "computercraft:gui/turtle_upgrade_left"},
     {"type": "minecraft:single", "resource": "computercraft:gui/turtle_upgrade_right"},
-    {"type": "minecraft:single", "resource": "computercraft:entity/printout"}
+    {"type": "minecraft:single", "resource": "computercraft:entity/printout"},
+    {"type": "minecraft:single", "resource": "computercraft:entity/pocket_computer_normal"},
+    {"type": "minecraft:single", "resource": "computercraft:entity/pocket_computer_advanced"},
+    {"type": "minecraft:single", "resource": "computercraft:entity/pocket_computer_colour"},
+    {"type": "minecraft:single", "resource": "computercraft:entity/pocket_computer_frame"},
+    {"type": "minecraft:single", "resource": "computercraft:entity/pocket_computer_light"}
   ]
 }

projects/common/src/main/java/dan200/computercraft/impl/AbstractComputerCraftAPI.java

@@ -12,6 +12,7 @@ import dan200.computercraft.api.filesystem.WritableMount;
 import dan200.computercraft.api.lua.GenericSource;
 import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.MediaProvider;
+import dan200.computercraft.api.media.PrintoutContents;
 import dan200.computercraft.api.network.PacketNetwork;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
@@ -26,6 +27,7 @@ import dan200.computercraft.shared.computer.core.ResourceMount;
 import dan200.computercraft.shared.computer.core.ServerContext;
 import dan200.computercraft.shared.details.BlockDetails;
 import dan200.computercraft.shared.details.ItemDetails;
+import dan200.computercraft.shared.media.items.PrintoutItem;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.Registry;
@@ -39,6 +41,7 @@ import javax.annotation.Nullable;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.stream.Stream;
 
 public abstract class AbstractComputerCraftAPI implements ComputerCraftAPIService {
     private final DetailRegistry<ItemStack> itemStackDetails = new DetailRegistryImpl<>(ItemDetails::fillBasic);
@@ -134,4 +137,21 @@ public abstract class AbstractComputerCraftAPI implements ComputerCraftAPIServic
     public final DetailRegistry<BlockReference> getBlockInWorldDetailRegistry() {
         return blockDetails;
     }
+
+    @Override
+    public @Nullable PrintoutContents getPrintoutContents(ItemStack stack) {
+        return stack.getItem() instanceof PrintoutItem ? new PrintoutContentsImpl(stack) : null;
+    }
+
+    public record PrintoutContentsImpl(ItemStack stack) implements PrintoutContents {
+        @Override
+        public String getTitle() {
+            return PrintoutItem.getTitle(stack);
+        }
+
+        @Override
+        public Stream<String> getTextLines() {
+            return Stream.of(PrintoutItem.getText(stack));
+        }
+    }
 }

projects/common/src/main/java/dan200/computercraft/shared/ModRegistry.java

@@ -28,6 +28,7 @@ import dan200.computercraft.shared.computer.blocks.CommandComputerBlock;
 import dan200.computercraft.shared.computer.blocks.ComputerBlock;
 import dan200.computercraft.shared.computer.blocks.ComputerBlockEntity;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
 import dan200.computercraft.shared.computer.items.CommandComputerItem;
 import dan200.computercraft.shared.computer.items.ComputerItem;
@@ -89,7 +90,6 @@ import dan200.computercraft.shared.turtle.recipes.TurtleOverlayRecipe;
 import dan200.computercraft.shared.turtle.recipes.TurtleRecipe;
 import dan200.computercraft.shared.turtle.recipes.TurtleUpgradeRecipe;
 import dan200.computercraft.shared.turtle.upgrades.*;
-import dan200.computercraft.shared.util.ComponentMap;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.commands.synchronization.ArgumentTypeInfo;
 import net.minecraft.commands.synchronization.SingletonArgumentInfo;
@@ -471,7 +471,7 @@ public final class ModRegistry {
 
         ComputerCraftAPI.registerAPIFactory(computer -> {
             var turtle = computer.getComponent(ComputerComponents.TURTLE);
-            var metrics = Objects.requireNonNull(computer.getComponent(ComponentMap.METRICS));
+            var metrics = Objects.requireNonNull(computer.getComponent(ServerComputer.METRICS));
             return turtle == null ? null : new TurtleAPI(metrics, (TurtleAccessInternal) turtle);
         });
 

projects/common/src/main/java/dan200/computercraft/shared/command/CommandComputerCraft.java

@@ -24,15 +24,13 @@ import dan200.computercraft.shared.computer.metrics.basic.AggregatedMetric;
 import dan200.computercraft.shared.computer.metrics.basic.BasicComputerMetricsObserver;
 import dan200.computercraft.shared.computer.metrics.basic.ComputerMetrics;
 import dan200.computercraft.shared.network.container.ComputerContainerData;
+import dan200.computercraft.shared.platform.PlatformHelper;
 import net.minecraft.ChatFormatting;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.core.BlockPos;
 import net.minecraft.network.chat.Component;
-import net.minecraft.world.MenuProvider;
 import net.minecraft.world.entity.RelativeMovement;
-import net.minecraft.world.entity.player.Inventory;
 import net.minecraft.world.entity.player.Player;
-import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.phys.Vec3;
@@ -260,18 +258,11 @@ public final class CommandComputerCraft {
      * @return The constant {@code 1}.
      */
     private static int view(CommandSourceStack source, ServerComputer computer) throws CommandSyntaxException {
-        var player = source.getPlayerOrException();
-        new ComputerContainerData(computer, ItemStack.EMPTY).open(player, new MenuProvider() {
-            @Override
-            public Component getDisplayName() {
-                return Component.translatable("gui.computercraft.view_computer");
-            }
-
-            @Override
-            public AbstractContainerMenu createMenu(int id, Inventory player, Player entity) {
-                return new ComputerMenuWithoutInventory(ModRegistry.Menus.COMPUTER.get(), id, player, p -> true, computer);
-            }
-        });
+        PlatformHelper.get().openMenu(
+            source.getPlayerOrException(), Component.translatable("gui.computercraft.view_computer"),
+            (id, player, entity) -> new ComputerMenuWithoutInventory(ModRegistry.Menus.COMPUTER.get(), id, player, p -> true, computer),
+            new ComputerContainerData(computer, ItemStack.EMPTY)
+        );
         return 1;
     }
 

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java

@@ -9,6 +9,7 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.shared.common.IBundledRedstoneBlock;
 import dan200.computercraft.shared.computer.items.IComputerItem;
 import dan200.computercraft.shared.network.container.ComputerContainerData;
+import dan200.computercraft.shared.platform.PlatformHelper;
 import dan200.computercraft.shared.platform.RegistryEntry;
 import dan200.computercraft.shared.util.BlockEntityHelpers;
 import net.minecraft.core.BlockPos;
@@ -161,7 +162,7 @@ public abstract class AbstractComputerBlock<T extends AbstractComputerBlockEntit
                 var serverComputer = computer.createServerComputer();
                 serverComputer.turnOn();
 
-                new ComputerContainerData(serverComputer, getItem(computer)).open(player, computer);
+                PlatformHelper.get().openMenu(player, computer.getName(), computer, new ComputerContainerData(serverComputer, getItem(computer)));
             }
             return InteractionResult.sidedSuccess(level.isClientSide);
         }

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlockEntity.java

@@ -26,9 +26,10 @@ import net.minecraft.network.chat.Component;
 import net.minecraft.network.protocol.game.ClientboundBlockEntityDataPacket;
 import net.minecraft.world.Container;
 import net.minecraft.world.LockCode;
-import net.minecraft.world.MenuProvider;
 import net.minecraft.world.Nameable;
 import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.MenuConstructor;
+import net.minecraft.world.level.block.GameMasterBlock;
 import net.minecraft.world.level.block.entity.BaseContainerBlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntityType;
@@ -38,7 +39,7 @@ import javax.annotation.Nullable;
 import java.util.Objects;
 import java.util.UUID;
 
-public abstract class AbstractComputerBlockEntity extends BlockEntity implements Nameable, MenuProvider {
+public abstract class AbstractComputerBlockEntity extends BlockEntity implements Nameable, MenuConstructor {
     private static final String NBT_ID = "ComputerId";
     private static final String NBT_LABEL = "Label";
     private static final String NBT_ON = "On";
@@ -310,6 +311,10 @@ public abstract class AbstractComputerBlockEntity extends BlockEntity implements
         return label;
     }
 
+    public final boolean isAdminOnly() {
+        return getBlockState().getBlock() instanceof GameMasterBlock;
+    }
+
     public final void setComputerID(int id) {
         if (getLevel().isClientSide || computerID == id) return;
 
@@ -417,4 +422,9 @@ public abstract class AbstractComputerBlockEntity extends BlockEntity implements
     public Component getDisplayName() {
         return Nameable.super.getDisplayName();
     }
+
+    @Override
+    public boolean onlyOpCanSetNbt() {
+        return isAdminOnly();
+    }
 }

projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java

@@ -11,8 +11,7 @@ import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ComputerState;
 import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
-import dan200.computercraft.shared.config.Config;
-import dan200.computercraft.shared.util.ComponentMap;
+import dan200.computercraft.shared.config.ConfigSpec;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.server.level.ServerLevel;
@@ -33,10 +32,9 @@ public class ComputerBlockEntity extends AbstractComputerBlockEntity {
 
     @Override
     protected ServerComputer createComputer(int id) {
-        return new ServerComputer(
-            (ServerLevel) getLevel(), getBlockPos(), id, label,
-            getFamily(), Config.computerTermWidth, Config.computerTermHeight,
-            ComponentMap.empty()
+        return new ServerComputer((ServerLevel) getLevel(), getBlockPos(), ServerComputer.properties(id, getFamily())
+            .label(getLabel())
+            .terminalSize(ConfigSpec.computerTermWidth.get(), ConfigSpec.computerTermHeight.get())
         );
     }
 

projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerSystem.java

@@ -11,7 +11,6 @@ import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.core.apis.ComputerAccess;
 import dan200.computercraft.core.apis.IAPIEnvironment;
 import dan200.computercraft.core.computer.ApiLifecycle;
-import dan200.computercraft.shared.util.ComponentMap;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 
@@ -26,11 +25,11 @@ import java.util.Map;
 final class ComputerSystem extends ComputerAccess implements IComputerSystem, ApiLifecycle {
     private final ServerComputer computer;
     private final IAPIEnvironment environment;
-    private final ComponentMap components;
+    private final Map<ComputerComponent<?>, Object> components;
 
     private boolean active;
 
-    ComputerSystem(ServerComputer computer, IAPIEnvironment environment, ComponentMap components) {
+    ComputerSystem(ServerComputer computer, IAPIEnvironment environment, Map<ComputerComponent<?>, Object> components) {
         super(environment);
         this.computer = computer;
         this.environment = environment;
@@ -95,7 +94,8 @@ final class ComputerSystem extends ComputerAccess implements IComputerSystem, Ap
     }
 
     @Override
+    @SuppressWarnings("unchecked")
     public <T> @Nullable T getComponent(ComputerComponent<T> component) {
-        return components.get(component);
+        return (T) components.get(component);
     }
 }

projects/common/src/main/java/dan200/computercraft/shared/computer/core/InputHandler.java

@@ -6,44 +6,33 @@ package dan200.computercraft.shared.computer.core;
 
 import dan200.computercraft.shared.computer.menu.ServerInputHandler;
 
-import javax.annotation.Nullable;
+import java.nio.ByteBuffer;
 
 /**
- * Handles user-provided input, forwarding it to a computer. This is used
+ * Handles user-provided input, forwarding it to a computer. This describes the "shape" of both the client-and
+ * server-side input handlers.
  *
  * @see ServerInputHandler
  * @see ServerComputer
  */
 public interface InputHandler {
-    void queueEvent(String event, @Nullable Object[] arguments);
+    void keyDown(int key, boolean repeat);
 
-    default void queueEvent(String event) {
-        queueEvent(event, null);
-    }
+    void keyUp(int key);
 
-    default void keyDown(int key, boolean repeat) {
-        queueEvent("key", new Object[]{ key, repeat });
-    }
+    void charTyped(byte chr);
 
-    default void keyUp(int key) {
-        queueEvent("key_up", new Object[]{ key });
-    }
+    void paste(ByteBuffer contents);
 
-    default void mouseClick(int button, int x, int y) {
-        queueEvent("mouse_click", new Object[]{ button, x, y });
-    }
+    void mouseClick(int button, int x, int y);
 
-    default void mouseUp(int button, int x, int y) {
-        queueEvent("mouse_up", new Object[]{ button, x, y });
-    }
+    void mouseUp(int button, int x, int y);
 
-    default void mouseDrag(int button, int x, int y) {
-        queueEvent("mouse_drag", new Object[]{ button, x, y });
-    }
+    void mouseDrag(int button, int x, int y);
 
-    default void mouseScroll(int direction, int x, int y) {
-        queueEvent("mouse_scroll", new Object[]{ direction, x, y });
-    }
+    void mouseScroll(int direction, int x, int y);
+
+    void terminate();
 
     void shutdown();
 

projects/common/src/main/java/dan200/computercraft/shared/computer/core/ServerComputer.java

@@ -6,12 +6,14 @@ package dan200.computercraft.shared.computer.core;
 
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.component.AdminComputer;
+import dan200.computercraft.api.component.ComputerComponent;
 import dan200.computercraft.api.component.ComputerComponents;
 import dan200.computercraft.api.filesystem.WritableMount;
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.WorkMonitor;
 import dan200.computercraft.core.computer.Computer;
 import dan200.computercraft.core.computer.ComputerEnvironment;
+import dan200.computercraft.core.computer.ComputerEvents;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.core.metrics.MetricsObserver;
 import dan200.computercraft.impl.ApiFactories;
@@ -23,18 +25,21 @@ import dan200.computercraft.shared.network.NetworkMessage;
 import dan200.computercraft.shared.network.client.ClientNetworkContext;
 import dan200.computercraft.shared.network.client.ComputerTerminalClientMessage;
 import dan200.computercraft.shared.network.server.ServerNetworking;
-import dan200.computercraft.shared.util.ComponentMap;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 
 import javax.annotation.Nullable;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.UUID;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Function;
 
-public class ServerComputer implements InputHandler, ComputerEnvironment {
+public class ServerComputer implements ComputerEnvironment, ComputerEvents.Receiver {
+    public static final ComputerComponent<MetricsObserver> METRICS = ComputerComponent.create("computercraft", "metrics");
+
     private final int instanceID;
     private final UUID instanceUUID = UUID.randomUUID();
 
@@ -50,30 +55,25 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
 
     private int ticksSincePing;
 
-    public ServerComputer(
-        ServerLevel level, BlockPos position, int computerID, @Nullable String label, ComputerFamily family, int terminalWidth, int terminalHeight,
-        ComponentMap baseComponents
-    ) {
+    public ServerComputer(ServerLevel level, BlockPos position, Properties properties) {
         this.level = level;
         this.position = position;
-        this.family = family;
+        this.family = properties.family;
 
         var context = ServerContext.get(level.getServer());
         instanceID = context.registry().getUnusedInstanceID();
-        terminal = new NetworkedTerminal(terminalWidth, terminalHeight, family != ComputerFamily.NORMAL, this::markTerminalChanged);
+        terminal = new NetworkedTerminal(properties.terminalWidth, properties.terminalHeight, family != ComputerFamily.NORMAL, this::markTerminalChanged);
         metrics = context.metrics().createMetricObserver(this);
 
-        var componentBuilder = ComponentMap.builder();
-        componentBuilder.add(ComponentMap.METRICS, metrics);
+        properties.addComponent(METRICS, metrics);
         if (family == ComputerFamily.COMMAND) {
-            componentBuilder.add(ComputerComponents.ADMIN_COMPUTER, new AdminComputer() {
+            properties.addComponent(ComputerComponents.ADMIN_COMPUTER, new AdminComputer() {
             });
         }
-        componentBuilder.add(baseComponents);
-        var components = componentBuilder.build();
+        var components = Map.copyOf(properties.components);
 
-        computer = new Computer(context.computerContext(), this, terminal, computerID);
-        computer.setLabel(label);
+        computer = new Computer(context.computerContext(), this, terminal, properties.computerID);
+        computer.setLabel(properties.label);
 
         // Load in the externally registered APIs.
         for (var factory : ApiFactories.getAll()) {
@@ -86,24 +86,24 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
         }
     }
 
-    public ComputerFamily getFamily() {
+    public final ComputerFamily getFamily() {
         return family;
     }
 
-    public ServerLevel getLevel() {
+    public final ServerLevel getLevel() {
         return level;
     }
 
-    public BlockPos getPosition() {
+    public final BlockPos getPosition() {
         return position;
     }
 
-    public void setPosition(ServerLevel level, BlockPos pos) {
+    public final void setPosition(ServerLevel level, BlockPos pos) {
         this.level = level;
         position = pos.immutable();
     }
 
-    protected void markTerminalChanged() {
+    protected final void markTerminalChanged() {
         terminalChanged.set(true);
     }
 
@@ -117,11 +117,11 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
         sendToAllInteracting(c -> new ComputerTerminalClientMessage(c, getTerminalState()));
     }
 
-    public TerminalState getTerminalState() {
+    public final TerminalState getTerminalState() {
         return TerminalState.create(terminal);
     }
 
-    public void keepAlive() {
+    public final void keepAlive() {
         ticksSincePing = 0;
     }
 
@@ -134,7 +134,7 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
      *
      * @return What sides on the computer have changed.
      */
-    public int pollRedstoneChanges() {
+    public final int pollRedstoneChanges() {
         return computer.pollRedstoneChanges();
     }
 
@@ -147,7 +147,7 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
         computer.unload();
     }
 
-    public void close() {
+    public final void close() {
         unload();
         ServerContext.get(level.getServer()).registry().remove(this);
     }
@@ -167,7 +167,7 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
         var server = level.getServer();
 
         for (var player : server.getPlayerList().getPlayers()) {
-            if (player.containerMenu instanceof ComputerMenu && ((ComputerMenu) player.containerMenu).getComputer() == this) {
+            if (player.containerMenu instanceof ComputerMenu menu && menu.getComputer() == this) {
                 ServerNetworking.sendToPlayer(createPacket.apply(player.containerMenu), player);
             }
         }
@@ -176,97 +176,135 @@ public class ServerComputer implements InputHandler, ComputerEnvironment {
     protected void onRemoved() {
     }
 
-    public int getInstanceID() {
+    public final int getInstanceID() {
         return instanceID;
     }
 
-    public UUID getInstanceUUID() {
+    public final UUID getInstanceUUID() {
         return instanceUUID;
     }
 
-    public int getID() {
+    public final int getID() {
         return computer.getID();
     }
 
-    public @Nullable String getLabel() {
+    public final @Nullable String getLabel() {
         return computer.getLabel();
     }
 
-    public boolean isOn() {
+    public final boolean isOn() {
         return computer.isOn();
     }
 
-    public ComputerState getState() {
+    public final ComputerState getState() {
         if (!computer.isOn()) return ComputerState.OFF;
         return computer.isBlinking() ? ComputerState.BLINKING : ComputerState.ON;
     }
 
-    @Override
-    public void turnOn() {
+    public final void turnOn() {
         computer.turnOn();
     }
 
-    @Override
-    public void shutdown() {
+    public final void shutdown() {
         computer.shutdown();
     }
 
-    @Override
-    public void reboot() {
+    public final void reboot() {
         computer.reboot();
     }
 
     @Override
-    public void queueEvent(String event, @Nullable Object[] arguments) {
+    public final void queueEvent(String event, @Nullable Object[] arguments) {
         computer.queueEvent(event, arguments);
     }
 
-    public int getRedstoneOutput(ComputerSide side) {
+    public final void queueEvent(String event) {
+        queueEvent(event, null);
+    }
+
+    public final int getRedstoneOutput(ComputerSide side) {
         return computer.isOn() ? computer.getRedstone().getExternalOutput(side) : 0;
     }
 
-    public void setRedstoneInput(ComputerSide side, int level, int bundledState) {
+    public final void setRedstoneInput(ComputerSide side, int level, int bundledState) {
         computer.getRedstone().setInput(side, level, bundledState);
     }
 
-    public int getBundledRedstoneOutput(ComputerSide side) {
+    public final int getBundledRedstoneOutput(ComputerSide side) {
         return computer.isOn() ? computer.getRedstone().getExternalBundledOutput(side) : 0;
     }
 
-    public void setPeripheral(ComputerSide side, @Nullable IPeripheral peripheral) {
+    public final void setPeripheral(ComputerSide side, @Nullable IPeripheral peripheral) {
         computer.getEnvironment().setPeripheral(side, peripheral);
     }
 
     @Nullable
-    public IPeripheral getPeripheral(ComputerSide side) {
+    public final IPeripheral getPeripheral(ComputerSide side) {
         return computer.getEnvironment().getPeripheral(side);
     }
 
-    public void setLabel(@Nullable String label) {
+    public final void setLabel(@Nullable String label) {
         computer.setLabel(label);
     }
 
     @Override
-    public double getTimeOfDay() {
+    public final double getTimeOfDay() {
         return (level.getDayTime() + 6000) % 24000 / 1000.0;
     }
 
     @Override
-    public int getDay() {
+    public final int getDay() {
         return (int) ((level.getDayTime() + 6000) / 24000) + 1;
     }
 
     @Override
-    public MetricsObserver getMetrics() {
+    public final MetricsObserver getMetrics() {
         return metrics;
     }
 
-    public WorkMonitor getMainThreadMonitor() {
+    public final WorkMonitor getMainThreadMonitor() {
         return computer.getMainThreadMonitor();
     }
 
     @Override
-    public @Nullable WritableMount createRootMount() {
+    public final WritableMount createRootMount() {
         return ComputerCraftAPI.createSaveDirMount(level.getServer(), "computer/" + computer.getID(), Config.computerSpaceLimit);
     }
+
+    public static Properties properties(int computerID, ComputerFamily family) {
+        return new Properties(computerID, family);
+    }
+
+    public static final class Properties {
+        private final int computerID;
+        private @Nullable String label;
+        private final ComputerFamily family;
+
+        private int terminalWidth = Config.DEFAULT_COMPUTER_TERM_WIDTH;
+        private int terminalHeight = Config.DEFAULT_COMPUTER_TERM_HEIGHT;
+        private final Map<ComputerComponent<?>, Object> components = new HashMap<>();
+
+        private Properties(int computerID, ComputerFamily family) {
+            this.computerID = computerID;
+            this.family = family;
+        }
+
+        public Properties label(@Nullable String label) {
+            this.label = label;
+            return this;
+        }
+
+        public Properties terminalSize(int width, int height) {
+            if (width <= 0 || height <= 0) throw new IllegalArgumentException("Terminal size must be positive");
+            this.terminalWidth = width;
+            this.terminalHeight = height;
+            return this;
+        }
+
+        public <T> Properties addComponent(ComputerComponent<T> component, T value) {
+            if (components.containsKey(component)) throw new IllegalArgumentException(component + " is already set");
+            components.put(component, value);
+            return this;
+        }
+    }
 }

projects/common/src/main/java/dan200/computercraft/shared/computer/menu/ServerInputState.java

@@ -7,6 +7,8 @@ package dan200.computercraft.shared.computer.menu;
 import dan200.computercraft.core.apis.handles.ByteBufferChannel;
 import dan200.computercraft.core.apis.transfer.TransferredFile;
 import dan200.computercraft.core.apis.transfer.TransferredFiles;
+import dan200.computercraft.core.computer.ComputerEvents;
+import dan200.computercraft.core.util.StringUtil;
 import dan200.computercraft.shared.computer.upload.FileSlice;
 import dan200.computercraft.shared.computer.upload.FileUpload;
 import dan200.computercraft.shared.computer.upload.UploadResult;
@@ -21,6 +23,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.annotation.Nullable;
+import java.nio.ByteBuffer;
 import java.util.List;
 import java.util.UUID;
 
@@ -48,21 +51,33 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
         this.owner = owner;
     }
 
-    @Override
-    public void queueEvent(String event, @Nullable Object[] arguments) {
-        owner.getComputer().queueEvent(event, arguments);
-    }
-
     @Override
     public void keyDown(int key, boolean repeat) {
         keysDown.add(key);
-        owner.getComputer().keyDown(key, repeat);
+        ComputerEvents.keyDown(owner.getComputer(), key, repeat);
     }
 
     @Override
     public void keyUp(int key) {
         keysDown.remove(key);
-        owner.getComputer().keyUp(key);
+        ComputerEvents.keyUp(owner.getComputer(), key);
+    }
+
+    @Override
+    public void charTyped(byte chr) {
+        if (StringUtil.isTypableChar(chr)) ComputerEvents.charTyped(owner.getComputer(), chr);
+    }
+
+    @Override
+    public void paste(ByteBuffer contents) {
+        if (contents.remaining() > 0 && isValidClipboard(contents)) ComputerEvents.paste(owner.getComputer(), contents);
+    }
+
+    private static boolean isValidClipboard(ByteBuffer buffer) {
+        for (int i = buffer.remaining(), max = buffer.limit(); i < max; i++) {
+            if (!StringUtil.isTypableChar(buffer.get(i))) return false;
+        }
+        return true;
     }
 
     @Override
@@ -71,7 +86,7 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
         lastMouseY = y;
         lastMouseDown = button;
 
-        owner.getComputer().mouseClick(button, x, y);
+        ComputerEvents.mouseClick(owner.getComputer(), button, x, y);
     }
 
     @Override
@@ -80,7 +95,7 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
         lastMouseY = y;
         lastMouseDown = -1;
 
-        owner.getComputer().mouseUp(button, x, y);
+        ComputerEvents.mouseUp(owner.getComputer(), button, x, y);
     }
 
     @Override
@@ -89,7 +104,7 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
         lastMouseY = y;
         lastMouseDown = button;
 
-        owner.getComputer().mouseDrag(button, x, y);
+        ComputerEvents.mouseDrag(owner.getComputer(), button, x, y);
     }
 
     @Override
@@ -97,7 +112,12 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
         lastMouseX = x;
         lastMouseY = y;
 
-        owner.getComputer().mouseScroll(direction, x, y);
+        ComputerEvents.mouseScroll(owner.getComputer(), direction, x, y);
+    }
+
+    @Override
+    public void terminate() {
+        owner.getComputer().queueEvent("terminate");
     }
 
     @Override
@@ -169,9 +189,9 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
     public void close() {
         var computer = owner.getComputer();
         var keys = keysDown.iterator();
-        while (keys.hasNext()) computer.keyUp(keys.nextInt());
+        while (keys.hasNext()) ComputerEvents.keyUp(computer, keys.nextInt());
 
-        if (lastMouseDown != -1) computer.mouseUp(lastMouseDown, lastMouseX, lastMouseY);
+        if (lastMouseDown != -1) ComputerEvents.mouseUp(computer, lastMouseDown, lastMouseX, lastMouseY);
 
         keysDown.clear();
         lastMouseDown = -1;

projects/common/src/main/java/dan200/computercraft/shared/config/Config.java

@@ -32,14 +32,14 @@ public final class Config {
     public static int advancedTurtleFuelLimit = 100000;
     public static boolean turtlesCanPush = true;
 
-    public static int computerTermWidth = 51;
-    public static int computerTermHeight = 19;
+    public static final int DEFAULT_COMPUTER_TERM_WIDTH = 51;
+    public static final int DEFAULT_COMPUTER_TERM_HEIGHT = 19;
 
-    public static final int turtleTermWidth = 39;
-    public static final int turtleTermHeight = 13;
+    public static final int TURTLE_TERM_WIDTH = 39;
+    public static final int TURTLE_TERM_HEIGHT = 13;
 
-    public static int pocketTermWidth = 26;
-    public static int pocketTermHeight = 20;
+    public static final int DEFAULT_POCKET_TERM_WIDTH = 26;
+    public static final int DEFAULT_POCKET_TERM_HEIGHT = 20;
 
     public static int monitorWidth = 8;
     public static int monitorHeight = 6;

projects/common/src/main/java/dan200/computercraft/shared/config/ConfigSpec.java

@@ -344,13 +344,13 @@ public final class ConfigSpec {
                 .push("term_sizes");
 
             builder.comment("Terminal size of computers.").push("computer");
-            computerTermWidth = builder.comment("Width of computer terminal").defineInRange("width", Config.computerTermWidth, 1, 255);
-            computerTermHeight = builder.comment("Height of computer terminal").defineInRange("height", Config.computerTermHeight, 1, 255);
+            computerTermWidth = builder.comment("Width of computer terminal").defineInRange("width", Config.DEFAULT_COMPUTER_TERM_WIDTH, 1, 255);
+            computerTermHeight = builder.comment("Height of computer terminal").defineInRange("height", Config.DEFAULT_COMPUTER_TERM_HEIGHT, 1, 255);
             builder.pop();
 
             builder.comment("Terminal size of pocket computers.").push("pocket_computer");
-            pocketTermWidth = builder.comment("Width of pocket computer terminal").defineInRange("width", Config.pocketTermWidth, 1, 255);
-            pocketTermHeight = builder.comment("Height of pocket computer terminal").defineInRange("height", Config.pocketTermHeight, 1, 255);
+            pocketTermWidth = builder.comment("Width of pocket computer terminal").defineInRange("width", Config.DEFAULT_POCKET_TERM_WIDTH, 1, 255);
+            pocketTermHeight = builder.comment("Height of pocket computer terminal").defineInRange("height", Config.DEFAULT_POCKET_TERM_HEIGHT, 1, 255);
             builder.pop();
 
             builder.comment("Maximum size of monitors (in blocks).").push("monitor");
@@ -437,10 +437,6 @@ public final class ConfigSpec {
         Config.turtlesCanPush = turtlesCanPush.get();
 
         // Terminal size
-        Config.computerTermWidth = computerTermWidth.get();
-        Config.computerTermHeight = computerTermHeight.get();
-        Config.pocketTermWidth = pocketTermWidth.get();
-        Config.pocketTermHeight = pocketTermHeight.get();
         Config.monitorWidth = monitorWidth.get();
         Config.monitorHeight = monitorHeight.get();
     }

projects/common/src/main/java/dan200/computercraft/shared/lectern/CustomLecternBlock.java

@@ -6,6 +6,7 @@ package dan200.computercraft.shared.lectern;
 
 import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.media.items.PrintoutItem;
+import dan200.computercraft.shared.util.BlockEntityHelpers;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.stats.Stats;
@@ -14,6 +15,7 @@ import net.minecraft.world.InteractionHand;
 import net.minecraft.world.InteractionResult;
 import net.minecraft.world.entity.item.ItemEntity;
 import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.Items;
 import net.minecraft.world.item.context.UseOnContext;
@@ -21,8 +23,12 @@ import net.minecraft.world.level.BlockGetter;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.LecternBlock;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.entity.BlockEntityTicker;
+import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.BlockHitResult;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Extends {@link LecternBlock} with support for {@linkplain PrintoutItem printouts}.
@@ -55,6 +61,27 @@ public class CustomLecternBlock extends LecternBlock {
         if (level.getBlockEntity(pos) instanceof CustomLecternBlockEntity be) be.setItem(item.split(1));
     }
 
+    /**
+     * A default implementation of {@link Item#useOn(UseOnContext)} for items that can be placed on a lectern.
+     *
+     * @param context The context of this item usage action.
+     * @return Whether the item was placed or not.
+     */
+    public static InteractionResult defaultUseItemOn(UseOnContext context) {
+        var level = context.getLevel();
+        var blockPos = context.getClickedPos();
+        var blockState = level.getBlockState(blockPos);
+        if (blockState.is(Blocks.LECTERN) && !blockState.getValue(LecternBlock.HAS_BOOK)) {
+            // If we have an empty lectern, place our book into it.
+            if (!level.isClientSide) {
+                CustomLecternBlock.replaceLectern(level, blockPos, blockState, context.getItemInHand());
+            }
+            return InteractionResult.sidedSuccess(level.isClientSide);
+        } else {
+            return InteractionResult.PASS;
+        }
+    }
+
     /**
      * Remove a custom lectern and replace it with an empty vanilla one.
      *
@@ -131,7 +158,7 @@ public class CustomLecternBlock extends LecternBlock {
                 clearLectern(level, pos, state);
             } else {
                 // Otherwise open the screen.
-                player.openMenu(lectern);
+                lectern.openMenu(player);
             }
 
             player.awardStat(Stats.INTERACT_WITH_LECTERN);
@@ -139,4 +166,11 @@ public class CustomLecternBlock extends LecternBlock {
 
         return InteractionResult.sidedSuccess(level.isClientSide);
     }
+
+    @Override
+    public @Nullable <T extends BlockEntity> BlockEntityTicker<T> getTicker(Level level, BlockState state, BlockEntityType<T> type) {
+        return level.isClientSide ? null : BlockEntityHelpers.createTickerHelper(type, ModRegistry.BlockEntities.LECTERN.get(), serverTicker);
+    }
+
+    private static final BlockEntityTicker<CustomLecternBlockEntity> serverTicker = (level, pos, state, lectern) -> lectern.tick();
 }

projects/common/src/main/java/dan200/computercraft/shared/lectern/CustomLecternBlockEntity.java

@@ -9,27 +9,25 @@ import dan200.computercraft.shared.container.BasicContainer;
 import dan200.computercraft.shared.container.SingleContainerData;
 import dan200.computercraft.shared.media.PrintoutMenu;
 import dan200.computercraft.shared.media.items.PrintoutItem;
+import dan200.computercraft.shared.pocket.core.PocketHolder;
+import dan200.computercraft.shared.pocket.items.PocketComputerItem;
 import dan200.computercraft.shared.util.BlockEntityHelpers;
 import net.minecraft.core.BlockPos;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.Tag;
-import net.minecraft.network.chat.Component;
 import net.minecraft.network.protocol.Packet;
 import net.minecraft.network.protocol.game.ClientGamePacketListener;
 import net.minecraft.network.protocol.game.ClientboundBlockEntityDataPacket;
 import net.minecraft.util.Mth;
 import net.minecraft.world.Container;
-import net.minecraft.world.MenuProvider;
-import net.minecraft.world.entity.player.Inventory;
+import net.minecraft.world.SimpleMenuProvider;
 import net.minecraft.world.entity.player.Player;
-import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.inventory.ContainerData;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.block.LecternBlock;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.LecternBlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
-import org.jetbrains.annotations.Nullable;
 
 import java.util.AbstractList;
 import java.util.List;
@@ -39,7 +37,7 @@ import java.util.List;
  *
  * @see LecternBlockEntity
  */
-public final class CustomLecternBlockEntity extends BlockEntity implements MenuProvider {
+public final class CustomLecternBlockEntity extends BlockEntity {
     private static final String NBT_ITEM = "Item";
     private static final String NBT_PAGE = "Page";
 
@@ -81,6 +79,12 @@ public final class CustomLecternBlockEntity extends BlockEntity implements MenuP
         }
     }
 
+    void tick() {
+        if (item.getItem() instanceof PocketComputerItem pocket) {
+            pocket.tick(item, new PocketHolder.LecternHolder(this), false);
+        }
+    }
+
     /**
      * Set the current page, emitting a redstone pulse if needed.
      *
@@ -123,24 +127,17 @@ public final class CustomLecternBlockEntity extends BlockEntity implements MenuP
         return tag;
     }
 
-    @Nullable
-    @Override
-    public AbstractContainerMenu createMenu(int containerId, Inventory playerInventory, Player player) {
+    void openMenu(Player player) {
         var item = getItem();
         if (item.getItem() instanceof PrintoutItem) {
-            return new PrintoutMenu(
-                containerId, new LecternContainer(), 0,
-                p -> Container.stillValidBlockEntity(this, player, Container.DEFAULT_DISTANCE_LIMIT),
+            player.openMenu(new SimpleMenuProvider((id, inventory, entity) -> new PrintoutMenu(
+                id, new LecternContainer(), 0,
+                p -> Container.stillValidBlockEntity(this, p, Container.DEFAULT_DISTANCE_LIMIT),
                 new PrintoutContainerData()
-            );
+            ), getItem().getDisplayName()));
+        } else if (item.getItem() instanceof PocketComputerItem pocket) {
+            pocket.open(player, item, new PocketHolder.LecternHolder(this), true);
         }
-
-        return null;
-    }
-
-    @Override
-    public Component getDisplayName() {
-        return getItem().getDisplayName();
     }
 
     /**

projects/common/src/main/java/dan200/computercraft/shared/media/items/PrintoutItem.java

@@ -19,8 +19,6 @@ import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.TooltipFlag;
 import net.minecraft.world.item.context.UseOnContext;
 import net.minecraft.world.level.Level;
-import net.minecraft.world.level.block.Blocks;
-import net.minecraft.world.level.block.LecternBlock;
 
 import javax.annotation.Nullable;
 import java.util.List;
@@ -56,18 +54,7 @@ public class PrintoutItem extends Item {
 
     @Override
     public InteractionResult useOn(UseOnContext context) {
-        var level = context.getLevel();
-        var blockPos = context.getClickedPos();
-        var blockState = level.getBlockState(blockPos);
-        if (blockState.is(Blocks.LECTERN) && !blockState.getValue(LecternBlock.HAS_BOOK)) {
-            // If we have an empty lectern, place our book into it.
-            if (!level.isClientSide) {
-                CustomLecternBlock.replaceLectern(level, blockPos, blockState, context.getItemInHand());
-            }
-            return InteractionResult.sidedSuccess(level.isClientSide);
-        } else {
-            return InteractionResult.PASS;
-        }
+        return CustomLecternBlock.defaultUseItemOn(context);
     }
 
     @Override

projects/common/src/main/java/dan200/computercraft/shared/network/NetworkMessages.java

@@ -27,9 +27,9 @@ public final class NetworkMessages {
     private static final List<MessageType<? extends NetworkMessage<ClientNetworkContext>>> clientMessages = new ArrayList<>();
 
     public static final MessageType<ComputerActionServerMessage> COMPUTER_ACTION = registerServerbound(0, "computer_action", ComputerActionServerMessage.class, ComputerActionServerMessage::new);
-    public static final MessageType<QueueEventServerMessage> QUEUE_EVENT = registerServerbound(1, "queue_event", QueueEventServerMessage.class, QueueEventServerMessage::new);
-    public static final MessageType<KeyEventServerMessage> KEY_EVENT = registerServerbound(2, "key_event", KeyEventServerMessage.class, KeyEventServerMessage::new);
-    public static final MessageType<MouseEventServerMessage> MOUSE_EVENT = registerServerbound(3, "mouse_event", MouseEventServerMessage.class, MouseEventServerMessage::new);
+    public static final MessageType<KeyEventServerMessage> KEY_EVENT = registerServerbound(1, "key_event", KeyEventServerMessage.class, KeyEventServerMessage::new);
+    public static final MessageType<MouseEventServerMessage> MOUSE_EVENT = registerServerbound(2, "mouse_event", MouseEventServerMessage.class, MouseEventServerMessage::new);
+    public static final MessageType<PasteEventComputerMessage> PASTE_EVENT = registerServerbound(3, "paste_event", PasteEventComputerMessage.class, PasteEventComputerMessage::new);
     public static final MessageType<UploadFileMessage> UPLOAD_FILE = registerServerbound(4, "upload_file", UploadFileMessage.class, UploadFileMessage::new);
 
     public static final MessageType<ChatTableClientMessage> CHAT_TABLE = registerClientbound(10, "chat_table", ChatTableClientMessage.class, ChatTableClientMessage::new);

projects/common/src/main/java/dan200/computercraft/shared/network/container/ContainerData.java

@@ -7,9 +7,7 @@ package dan200.computercraft.shared.network.container;
 import dan200.computercraft.shared.network.NetworkMessage;
 import dan200.computercraft.shared.platform.PlatformHelper;
 import net.minecraft.network.FriendlyByteBuf;
-import net.minecraft.world.MenuProvider;
 import net.minecraft.world.entity.player.Inventory;
-import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.inventory.MenuType;
 
@@ -21,16 +19,6 @@ import java.util.function.Function;
 public interface ContainerData {
     void toBytes(FriendlyByteBuf buf);
 
-    /**
-     * Open a menu for a specific player using this data.
-     *
-     * @param player The player to open the menu for.
-     * @param menu   The underlying menu provider.
-     */
-    default void open(Player player, MenuProvider menu) {
-        PlatformHelper.get().openMenu(player, menu, this);
-    }
-
     static <C extends AbstractContainerMenu, T extends ContainerData> MenuType<C> toType(Function<FriendlyByteBuf, T> reader, Factory<C, T> factory) {
         return PlatformHelper.get().createMenuType(reader, factory);
     }

projects/common/src/main/java/dan200/computercraft/shared/network/server/ComputerActionServerMessage.java

@@ -33,6 +33,7 @@ public class ComputerActionServerMessage extends ComputerServerMessage {
     @Override
     protected void handle(ServerNetworkContext context, ComputerMenu container) {
         switch (action) {
+            case TERMINATE -> container.getInput().terminate();
             case TURN_ON -> container.getInput().turnOn();
             case REBOOT -> container.getInput().reboot();
             case SHUTDOWN -> container.getInput().shutdown();
@@ -45,6 +46,7 @@ public class ComputerActionServerMessage extends ComputerServerMessage {
     }
 
     public enum Action {
+        TERMINATE,
         TURN_ON,
         SHUTDOWN,
         REBOOT

projects/common/src/main/java/dan200/computercraft/shared/network/server/ComputerServerMessage.java

@@ -35,8 +35,8 @@ public abstract class ComputerServerMessage implements NetworkMessage<ServerNetw
     @Override
     public void handle(ServerNetworkContext context) {
         Player player = context.getSender();
-        if (player.containerMenu.containerId == containerId && player.containerMenu instanceof ComputerMenu) {
-            handle(context, (ComputerMenu) player.containerMenu);
+        if (player.containerMenu.containerId == containerId && player.containerMenu instanceof ComputerMenu menu) {
+            handle(context, menu);
         }
     }
 

projects/common/src/main/java/dan200/computercraft/shared/network/server/KeyEventServerMessage.java

@@ -37,10 +37,11 @@ public class KeyEventServerMessage extends ComputerServerMessage {
     @Override
     protected void handle(ServerNetworkContext context, ComputerMenu container) {
         var input = container.getInput();
-        if (type == Action.UP) {
-            input.keyUp(key);
-        } else {
-            input.keyDown(key, type == Action.REPEAT);
+        switch (type) {
+            case UP -> input.keyUp(key);
+            case DOWN -> input.keyDown(key, false);
+            case REPEAT -> input.keyDown(key, true);
+            case CHAR -> input.charTyped((byte) key);
         }
     }
 
@@ -50,6 +51,6 @@ public class KeyEventServerMessage extends ComputerServerMessage {
     }
 
     public enum Action {
-        DOWN, REPEAT, UP
+        DOWN, REPEAT, UP, CHAR
     }
 }

projects/common/src/main/java/dan200/computercraft/shared/network/server/PasteEventComputerMessage.java

@@ -0,0 +1,61 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.network.server;
+
+import dan200.computercraft.core.util.StringUtil;
+import dan200.computercraft.shared.computer.core.ServerComputer;
+import dan200.computercraft.shared.computer.menu.ComputerMenu;
+import dan200.computercraft.shared.computer.menu.ServerInputHandler;
+import dan200.computercraft.shared.network.MessageType;
+import dan200.computercraft.shared.network.NetworkMessages;
+import io.netty.handler.codec.DecoderException;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.world.inventory.AbstractContainerMenu;
+
+import java.nio.ByteBuffer;
+
+/**
+ * Paste a string on a {@link ServerComputer}.
+ *
+ * @see ServerInputHandler#paste(ByteBuffer)
+ */
+public class PasteEventComputerMessage extends ComputerServerMessage {
+    private final ByteBuffer text;
+
+    public PasteEventComputerMessage(AbstractContainerMenu menu, ByteBuffer text) {
+        super(menu);
+        this.text = text;
+    }
+
+    public PasteEventComputerMessage(FriendlyByteBuf buf) {
+        super(buf);
+
+        var length = buf.readVarInt();
+        if (length > StringUtil.MAX_PASTE_LENGTH) {
+            throw new DecoderException("ByteArray with size " + length + " is bigger than allowed " + StringUtil.MAX_PASTE_LENGTH);
+        }
+
+        var text = new byte[length];
+        buf.readBytes(text);
+        this.text = ByteBuffer.wrap(text);
+    }
+
+    @Override
+    public void write(FriendlyByteBuf buf) {
+        super.write(buf);
+        buf.writeVarInt(text.remaining());
+        buf.writeBytes(text.duplicate());
+    }
+
+    @Override
+    protected void handle(ServerNetworkContext context, ComputerMenu container) {
+        container.getInput().paste(text);
+    }
+
+    @Override
+    public MessageType<PasteEventComputerMessage> type() {
+        return NetworkMessages.PASTE_EVENT;
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/network/server/QueueEventServerMessage.java

@@ -1,57 +0,0 @@
-// SPDX-FileCopyrightText: 2018 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.network.server;
-
-import dan200.computercraft.shared.computer.core.ServerComputer;
-import dan200.computercraft.shared.computer.menu.ComputerMenu;
-import dan200.computercraft.shared.computer.menu.ServerInputHandler;
-import dan200.computercraft.shared.network.MessageType;
-import dan200.computercraft.shared.network.NetworkMessages;
-import dan200.computercraft.shared.util.NBTUtil;
-import net.minecraft.network.FriendlyByteBuf;
-import net.minecraft.world.inventory.AbstractContainerMenu;
-
-import javax.annotation.Nullable;
-
-/**
- * Queue an event on a {@link ServerComputer}.
- *
- * @see ServerInputHandler#queueEvent(String)
- */
-public class QueueEventServerMessage extends ComputerServerMessage {
-    private final String event;
-    private final @Nullable Object[] args;
-
-    public QueueEventServerMessage(AbstractContainerMenu menu, String event, @Nullable Object[] args) {
-        super(menu);
-        this.event = event;
-        this.args = args;
-    }
-
-    public QueueEventServerMessage(FriendlyByteBuf buf) {
-        super(buf);
-        event = buf.readUtf(Short.MAX_VALUE);
-
-        var args = buf.readNbt();
-        this.args = args == null ? null : NBTUtil.decodeObjects(args);
-    }
-
-    @Override
-    public void write(FriendlyByteBuf buf) {
-        super.write(buf);
-        buf.writeUtf(event);
-        buf.writeNbt(args == null ? null : NBTUtil.encodeObjects(args));
-    }
-
-    @Override
-    protected void handle(ServerNetworkContext context, ComputerMenu container) {
-        container.getInput().queueEvent(event, args);
-    }
-
-    @Override
-    public MessageType<QueueEventServerMessage> type() {
-        return NetworkMessages.QUEUE_EVENT;
-    }
-}

projects/common/src/main/java/dan200/computercraft/shared/peripheral/monitor/MonitorBlockEntity.java

@@ -18,6 +18,7 @@ import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.network.protocol.game.ClientboundBlockEntityDataPacket;
+import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
@@ -237,7 +238,7 @@ public class MonitorBlockEntity extends BlockEntity {
         getLevel().setBlock(getBlockPos(), getBlockState()
             .setValue(MonitorBlock.STATE, MonitorEdgeState.fromConnections(
                 yIndex < height - 1, yIndex > 0,
-                xIndex > 0, xIndex < width - 1)), 2);
+                xIndex > 0, xIndex < width - 1)), Block.UPDATE_CLIENTS);
     }
 
     // region Sizing and placement stuff

projects/common/src/main/java/dan200/computercraft/shared/platform/PlatformHelper.java

@@ -20,6 +20,7 @@ import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.Registry;
 import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.network.chat.Component;
 import net.minecraft.network.protocol.Packet;
 import net.minecraft.network.protocol.game.ClientGamePacketListener;
 import net.minecraft.resources.ResourceKey;
@@ -29,11 +30,15 @@ import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.server.level.ServerPlayerGameMode;
 import net.minecraft.server.network.ServerGamePacketListenerImpl;
 import net.minecraft.tags.TagKey;
-import net.minecraft.world.*;
+import net.minecraft.world.Container;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.InteractionResult;
+import net.minecraft.world.WorldlyContainer;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.inventory.CraftingContainer;
+import net.minecraft.world.inventory.MenuConstructor;
 import net.minecraft.world.inventory.MenuType;
 import net.minecraft.world.item.CreativeModeTab;
 import net.minecraft.world.item.DyeColor;
@@ -159,10 +164,11 @@ public interface PlatformHelper extends dan200.computercraft.impl.PlatformHelper
      * Open a container using a specific {@link ContainerData}.
      *
      * @param player The player to open the menu for.
-     * @param owner  The underlying menu provider.
-     * @param menu   The menu data.
+     * @param title  The title for this menu.
+     * @param menu   The underlying menu constructor.
+     * @param data   The menu data.
      */
-    void openMenu(Player player, MenuProvider owner, ContainerData menu);
+    void openMenu(Player player, Component title, MenuConstructor menu, ContainerData data);
 
     /**
      * Create a new {@link MessageType}.

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketBrain.java

@@ -10,7 +10,7 @@ import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.shared.common.IColouredItem;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.network.client.PocketComputerDataMessage;
 import dan200.computercraft.shared.network.server.ServerNetworking;
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
@@ -44,8 +44,8 @@ public final class PocketBrain implements IPocketAccess {
     private int colour = -1;
     private int lightColour = -1;
 
-    public PocketBrain(PocketHolder holder, int computerID, @Nullable String label, ComputerFamily family, @Nullable UpgradeData<IPocketUpgrade> upgrade) {
-        this.computer = new PocketServerComputer(this, holder, computerID, label, family);
+    public PocketBrain(PocketHolder holder, @Nullable UpgradeData<IPocketUpgrade> upgrade, ServerComputer.Properties properties) {
+        this.computer = new PocketServerComputer(this, holder, properties);
         this.holder = holder;
         this.position = holder.pos();
         this.upgrade = UpgradeData.copyOf(upgrade);

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketHolder.java

@@ -5,7 +5,9 @@
 package dan200.computercraft.shared.pocket.core;
 
 import dan200.computercraft.shared.computer.core.ServerComputer;
+import dan200.computercraft.shared.lectern.CustomLecternBlockEntity;
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
+import dan200.computercraft.shared.util.BlockEntityHelpers;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
@@ -51,6 +53,15 @@ public sealed interface PocketHolder {
      */
     void setChanged();
 
+    /**
+     * Whether the terminal is visible to all players in range, and so should be broadcast to everyone.
+     *
+     * @return Whether to send the terminal.
+     */
+    default boolean isTerminalAlwaysVisible() {
+        return false;
+    }
+
     /**
      * An {@link Entity} holding a pocket computer.
      */
@@ -112,4 +123,41 @@ public sealed interface PocketHolder {
             entity.setItem(entity.getItem().copy());
         }
     }
+
+    /**
+     * A pocket computer in a {@link CustomLecternBlockEntity}.
+     *
+     * @param lectern The lectern holding this item.
+     */
+    record LecternHolder(CustomLecternBlockEntity lectern) implements PocketHolder {
+        @Override
+        public ServerLevel level() {
+            return (ServerLevel) lectern.getLevel();
+        }
+
+        @Override
+        public Vec3 pos() {
+            return Vec3.atCenterOf(lectern.getBlockPos());
+        }
+
+        @Override
+        public BlockPos blockPos() {
+            return lectern.getBlockPos();
+        }
+
+        @Override
+        public boolean isValid(ServerComputer computer) {
+            return !lectern().isRemoved() && PocketComputerItem.isServerComputer(computer, lectern.getItem());
+        }
+
+        @Override
+        public void setChanged() {
+            BlockEntityHelpers.updateBlock(lectern());
+        }
+
+        @Override
+        public boolean isTerminalAlwaysVisible() {
+            return true;
+        }
+    }
 }

projects/common/src/main/java/dan200/computercraft/shared/pocket/core/PocketServerComputer.java

@@ -5,15 +5,13 @@
 package dan200.computercraft.shared.pocket.core;
 
 import dan200.computercraft.api.component.ComputerComponents;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ComputerState;
 import dan200.computercraft.shared.computer.core.ServerComputer;
-import dan200.computercraft.shared.config.Config;
+import dan200.computercraft.shared.config.ConfigSpec;
 import dan200.computercraft.shared.network.client.PocketComputerDataMessage;
 import dan200.computercraft.shared.network.client.PocketComputerDeletedClientMessage;
 import dan200.computercraft.shared.network.server.ServerNetworking;
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
-import dan200.computercraft.shared.util.ComponentMap;
 import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.level.ChunkPos;
 
@@ -41,10 +39,10 @@ public final class PocketServerComputer extends ServerComputer {
 
     private Set<ServerPlayer> tracking = Set.of();
 
-    PocketServerComputer(PocketBrain brain, PocketHolder holder, int computerID, @Nullable String label, ComputerFamily family) {
-        super(
-            holder.level(), holder.blockPos(), computerID, label, family, Config.pocketTermWidth, Config.pocketTermHeight,
-            ComponentMap.builder().add(ComputerComponents.POCKET, brain).build()
+    PocketServerComputer(PocketBrain brain, PocketHolder holder, ServerComputer.Properties properties) {
+        super(holder.level(), holder.blockPos(), properties
+            .terminalSize(ConfigSpec.pocketTermWidth.get(), ConfigSpec.pocketTermHeight.get())
+            .addComponent(ComputerComponents.POCKET, brain)
         );
         this.brain = brain;
     }
@@ -74,7 +72,7 @@ public final class PocketServerComputer extends ServerComputer {
             // Broadcast the state to new players.
             var added = newTracking.stream().filter(x -> !tracking.contains(x)).toList();
             if (!added.isEmpty()) {
-                ServerNetworking.sendToPlayers(new PocketComputerDataMessage(this, false), added);
+                ServerNetworking.sendToPlayers(new PocketComputerDataMessage(this, brain.holder().isTerminalAlwaysVisible()), added);
             }
         }
 
@@ -85,9 +83,15 @@ public final class PocketServerComputer extends ServerComputer {
     protected void onTerminalChanged() {
         super.onTerminalChanged();
 
-        if (brain.holder() instanceof PocketHolder.PlayerHolder holder && holder.isValid(this)) {
-            // Broadcast the terminal to the current player.
-            ServerNetworking.sendToPlayer(new PocketComputerDataMessage(this, true), holder.entity());
+        var holder = brain.holder() instanceof PocketHolder.PlayerHolder h && h.isValid(this) ? h.entity() : null;
+        if (brain.holder().isTerminalAlwaysVisible() && !tracking.isEmpty()) {
+            // If the terminal is always visible, send it to all players *and* the holder.
+            var packet = new PocketComputerDataMessage(this, true);
+            ServerNetworking.sendToPlayers(packet, tracking);
+            if (holder != null && !tracking.contains(holder)) ServerNetworking.sendToPlayer(packet, holder);
+        } else if (holder != null) {
+            // Otherwise just send it to the holder.
+            ServerNetworking.sendToPlayer(new PocketComputerDataMessage(this, true), holder);
         }
     }
 

projects/common/src/main/java/dan200/computercraft/shared/pocket/inventory/PocketComputerMenuProvider.java

@@ -1,56 +0,0 @@
-// SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.pocket.inventory;
-
-import dan200.computercraft.shared.ModRegistry;
-import dan200.computercraft.shared.computer.core.ServerComputer;
-import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
-import dan200.computercraft.shared.pocket.items.PocketComputerItem;
-import net.minecraft.network.chat.Component;
-import net.minecraft.world.InteractionHand;
-import net.minecraft.world.MenuProvider;
-import net.minecraft.world.entity.player.Inventory;
-import net.minecraft.world.entity.player.Player;
-import net.minecraft.world.inventory.AbstractContainerMenu;
-import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
-
-import static dan200.computercraft.core.util.Nullability.assertNonNull;
-
-public class PocketComputerMenuProvider implements MenuProvider {
-    private final ServerComputer computer;
-    private final Component name;
-    private final PocketComputerItem item;
-    private final InteractionHand hand;
-    private final boolean isTypingOnly;
-
-    public PocketComputerMenuProvider(ServerComputer computer, ItemStack stack, PocketComputerItem item, InteractionHand hand, boolean isTypingOnly) {
-        this.computer = computer;
-        name = stack.getHoverName();
-        this.item = item;
-        this.hand = hand;
-        this.isTypingOnly = isTypingOnly;
-    }
-
-
-    @Override
-    public Component getDisplayName() {
-        return name;
-    }
-
-    @Nullable
-    @Override
-    public AbstractContainerMenu createMenu(int id, Inventory inventory, Player entity) {
-        return new ComputerMenuWithoutInventory(
-            isTypingOnly ? ModRegistry.Menus.POCKET_COMPUTER_NO_TERM.get() : ModRegistry.Menus.COMPUTER.get(), id, inventory,
-            p -> {
-                var stack = p.getItemInHand(hand);
-                return stack.getItem() == item && PocketComputerItem.getServerComputer(assertNonNull(entity.level().getServer()), stack) == computer;
-            },
-            computer
-        );
-    }
-}

projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java

@@ -12,18 +12,21 @@ import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.impl.PocketUpgrades;
+import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ServerComputer;
 import dan200.computercraft.shared.computer.core.ServerComputerRegistry;
 import dan200.computercraft.shared.computer.core.ServerContext;
+import dan200.computercraft.shared.computer.inventory.ComputerMenuWithoutInventory;
 import dan200.computercraft.shared.computer.items.IComputerItem;
 import dan200.computercraft.shared.config.Config;
+import dan200.computercraft.shared.lectern.CustomLecternBlock;
 import dan200.computercraft.shared.network.container.ComputerContainerData;
+import dan200.computercraft.shared.platform.PlatformHelper;
 import dan200.computercraft.shared.pocket.core.PocketBrain;
 import dan200.computercraft.shared.pocket.core.PocketHolder;
 import dan200.computercraft.shared.pocket.core.PocketServerComputer;
-import dan200.computercraft.shared.pocket.inventory.PocketComputerMenuProvider;
 import dan200.computercraft.shared.util.IDAssigner;
 import dan200.computercraft.shared.util.InventoryUtil;
 import dan200.computercraft.shared.util.NBTUtil;
@@ -42,6 +45,7 @@ import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.TooltipFlag;
+import net.minecraft.world.item.context.UseOnContext;
 import net.minecraft.world.level.Level;
 
 import javax.annotation.Nullable;
@@ -79,12 +83,20 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
     /**
      * Tick a pocket computer.
      *
-     * @param stack  The current pocket computer stack.
-     * @param holder The entity holding the pocket item.
-     * @param brain  The pocket computer brain.
+     * @param stack   The current pocket computer stack.
+     * @param holder  The entity holding the pocket item.
+     * @param passive If set, the pocket computer will not be created if it doesn't exist, and will not be kept alive.
      */
-    private void tick(ItemStack stack, PocketHolder holder, PocketBrain brain) {
-        brain.updateHolder(holder);
+    public void tick(ItemStack stack, PocketHolder holder, boolean passive) {
+        PocketBrain brain;
+        if (passive) {
+            var computer = getServerComputer(holder.level().getServer(), stack);
+            if (computer == null) return;
+            brain = computer.getBrain();
+        } else {
+            brain = getOrCreateBrain(holder.level(), holder, stack);
+            brain.computer().keepAlive();
+        }
 
         // Update pocket upgrade
         var upgrade = brain.getUpgrade();
@@ -137,11 +149,7 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
         if (slot < 0) return;
 
         // If we're in the inventory, create a computer and keep it alive.
-        var holder = new PocketHolder.PlayerHolder(player, slot);
-        var brain = getOrCreateBrain((ServerLevel) world, holder, stack);
-        brain.computer().keepAlive();
-
-        tick(stack, holder, brain);
+        tick(stack, new PocketHolder.PlayerHolder(player, slot), false);
     }
 
     @ForgeOverride
@@ -151,12 +159,16 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
 
         // If we're an item entity, tick an already existing computer (as to update the position), but do not keep the
         // computer alive.
-        var computer = getServerComputer(level.getServer(), stack);
-        if (computer != null) tick(stack, new PocketHolder.ItemEntityHolder(entity), computer.getBrain());
+        tick(stack, new PocketHolder.ItemEntityHolder(entity), true);
 
         return false;
     }
 
+    @Override
+    public InteractionResult useOn(UseOnContext context) {
+        return CustomLecternBlock.defaultUseItemOn(context);
+    }
+
     @Override
     public InteractionResultHolder<ItemStack> use(Level world, Player player, InteractionHand hand) {
         var stack = player.getItemInHand(hand);
@@ -169,20 +181,39 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
             var stop = false;
             var upgrade = getUpgrade(stack);
             if (upgrade != null) {
-                brain.updateHolder(holder);
                 stop = upgrade.onRightClick(world, brain, computer.getPeripheral(ComputerSide.BACK));
                 // Sync back just in case. We don't need to setChanged, as we'll return the item anyway.
                 updateItem(stack, brain);
             }
 
-            if (!stop) {
-                var isTypingOnly = hand == InteractionHand.OFF_HAND;
-                new ComputerContainerData(computer, stack).open(player, new PocketComputerMenuProvider(computer, stack, this, hand, isTypingOnly));
-            }
+            if (!stop) openImpl(player, stack, holder, hand == InteractionHand.OFF_HAND, computer);
         }
         return new InteractionResultHolder<>(InteractionResult.sidedSuccess(world.isClientSide), stack);
     }
 
+    /**
+     * Open a container for this pocket computer.
+     *
+     * @param player       The player to show the menu for.
+     * @param stack        The pocket computer stack.
+     * @param holder       The holder of the pocket computer.
+     * @param isTypingOnly Open the off-hand pocket screen (only supporting typing, with no visible terminal).
+     */
+    public void open(Player player, ItemStack stack, PocketHolder holder, boolean isTypingOnly) {
+        var brain = getOrCreateBrain(holder.level(), holder, stack);
+        var computer = brain.computer();
+        computer.turnOn();
+        openImpl(player, stack, holder, isTypingOnly, computer);
+    }
+
+    private static void openImpl(Player player, ItemStack stack, PocketHolder holder, boolean isTypingOnly, ServerComputer computer) {
+        PlatformHelper.get().openMenu(player, stack.getHoverName(), (id, inventory, entity) -> new ComputerMenuWithoutInventory(
+            isTypingOnly ? ModRegistry.Menus.POCKET_COMPUTER_NO_TERM.get() : ModRegistry.Menus.COMPUTER.get(), id, inventory,
+            p -> holder.isValid(computer),
+            computer
+        ), new ComputerContainerData(computer, stack));
+    }
+
     @Override
     public Component getName(ItemStack stack) {
         var baseString = getDescriptionId(stack);
@@ -226,7 +257,11 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
         var registry = ServerContext.get(level.getServer()).registry();
         {
             var computer = getServerComputer(registry, stack);
-            if (computer != null) return computer.getBrain();
+            if (computer != null) {
+                var brain = computer.getBrain();
+                brain.updateHolder(holder);
+                return brain;
+            }
         }
 
         var computerID = getComputerID(stack);
@@ -235,15 +270,17 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
             setComputerID(stack, computerID);
         }
 
-        var brain = new PocketBrain(holder, getComputerID(stack), getLabel(stack), getFamily(), getUpgradeWithData(stack));
+        var brain = new PocketBrain(
+            holder, getUpgradeWithData(stack),
+            ServerComputer.properties(getComputerID(stack), getFamily()).label(getLabel(stack))
+        );
         var computer = brain.computer();
 
         var tag = stack.getOrCreateTag();
         tag.putInt(NBT_SESSION, registry.getSessionID());
         tag.putUUID(NBT_INSTANCE, computer.register());
 
-        // Only turn on when initially creating the computer, rather than each tick.
-        if (isMarkedOn(stack) && holder instanceof PocketHolder.PlayerHolder) computer.turnOn();
+        if (isMarkedOn(stack)) computer.turnOn();
 
         updateItem(stack, brain);
 

projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlockEntity.java

@@ -20,7 +20,6 @@ import dan200.computercraft.shared.config.Config;
 import dan200.computercraft.shared.container.BasicContainer;
 import dan200.computercraft.shared.turtle.core.TurtleBrain;
 import dan200.computercraft.shared.turtle.inventory.TurtleMenu;
-import dan200.computercraft.shared.util.ComponentMap;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.NonNullList;
@@ -74,10 +73,10 @@ public class TurtleBlockEntity extends AbstractComputerBlockEntity implements Ba
 
     @Override
     protected ServerComputer createComputer(int id) {
-        var computer = new ServerComputer(
-            (ServerLevel) getLevel(), getBlockPos(), id, label,
-            getFamily(), Config.turtleTermWidth, Config.turtleTermHeight,
-            ComponentMap.builder().add(ComputerComponents.TURTLE, brain).build()
+        var computer = new ServerComputer((ServerLevel) getLevel(), getBlockPos(), ServerComputer.properties(id, getFamily())
+            .label(getLabel())
+            .terminalSize(Config.TURTLE_TERM_WIDTH, Config.TURTLE_TERM_HEIGHT)
+            .addComponent(ComputerComponents.TURTLE, brain)
         );
         brain.setupComputer(computer);
         return computer;

projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java

@@ -36,6 +36,7 @@ import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.MoverType;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.material.PushReaction;
 import net.minecraft.world.phys.AABB;
 import net.minecraft.world.phys.Vec3;
@@ -280,7 +281,7 @@ public class TurtleBrain implements TurtleAccessInternal {
         try {
             // We use Block.UPDATE_CLIENTS here to ensure that neighbour updates caused in Block.updateNeighbourShapes
             // are sent to the client. We want to avoid doing a full block update until the turtle state is copied over.
-            if (world.setBlock(pos, newState, 2)) {
+            if (world.setBlock(pos, newState, Block.UPDATE_CLIENTS)) {
                 var block = world.getBlockState(pos).getBlock();
                 if (block == oldBlock.getBlock()) {
                     var newTile = world.getBlockEntity(pos);
@@ -691,7 +692,7 @@ public class TurtleBrain implements TurtleAccessInternal {
                     }
 
                     var aabb = new AABB(minX, minY, minZ, maxX, maxY, maxZ);
-                    var list = world.getEntitiesOfClass(Entity.class, aabb, TurtleBrain::canPush);
+                    var list = world.getEntities((Entity) null, aabb, TurtleBrain::canPush);
                     if (!list.isEmpty()) {
                         double pushStep = 1.0f / ANIM_DURATION;
                         var pushStepX = moveDir.getStepX() * pushStep;

projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleDetectCommand.java

@@ -22,11 +22,10 @@ public class TurtleDetectCommand implements TurtleCommand {
         var direction = this.direction.toWorldDir(turtle);
 
         // Check if thing in front is air or not
-        var world = turtle.getLevel();
-        var oldPosition = turtle.getPosition();
-        var newPosition = oldPosition.relative(direction);
+        var level = turtle.getLevel();
+        var pos = turtle.getPosition().relative(direction);
 
-        return !WorldUtil.isLiquidBlock(world, newPosition) && !world.isEmptyBlock(newPosition)
+        return !WorldUtil.isEmptyBlock(level.getBlockState(pos))
             ? TurtleCommandResult.success()
             : TurtleCommandResult.failure();
     }

projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleMoveCommand.java

@@ -13,9 +13,9 @@ import dan200.computercraft.shared.util.WorldUtil;
 import net.minecraft.core.BlockPos;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.entity.Entity;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.material.PushReaction;
 import net.minecraft.world.phys.AABB;
-import net.minecraft.world.phys.shapes.Shapes;
-import net.minecraft.world.phys.shapes.VoxelShape;
 
 public class TurtleMoveCommand implements TurtleCommand {
     private final MoveDirection direction;
@@ -30,57 +30,32 @@ public class TurtleMoveCommand implements TurtleCommand {
         var direction = this.direction.toWorldDir(turtle);
 
         // Check if we can move
-        var oldWorld = (ServerLevel) turtle.getLevel();
+        var level = (ServerLevel) turtle.getLevel();
         var oldPosition = turtle.getPosition();
         var newPosition = oldPosition.relative(direction);
 
         var turtlePlayer = TurtlePlayer.getWithPosition(turtle, oldPosition, direction);
-        var canEnterResult = canEnter(turtlePlayer, oldWorld, newPosition);
-        if (!canEnterResult.isSuccess()) {
-            return canEnterResult;
-        }
+        var canEnterResult = canEnter(turtlePlayer, level, newPosition);
+        if (!canEnterResult.isSuccess()) return canEnterResult;
 
-        // Check existing block is air or replaceable
-        var state = oldWorld.getBlockState(newPosition);
-        if (!oldWorld.isEmptyBlock(newPosition) &&
-            !WorldUtil.isLiquidBlock(oldWorld, newPosition) &&
-            !state.canBeReplaced()) {
+        // Check existing block is air or replaceable.
+        var existingState = level.getBlockState(newPosition);
+        if (!(WorldUtil.isEmptyBlock(existingState) || existingState.canBeReplaced())) {
             return TurtleCommandResult.failure("Movement obstructed");
         }
 
-        // Check there isn't anything in the way
-        var collision = state.getCollisionShape(oldWorld, oldPosition).move(
-            newPosition.getX(),
-            newPosition.getY(),
-            newPosition.getZ()
-        );
-
-        if (!oldWorld.isUnobstructed(null, collision)) {
-            if (!Config.turtlesCanPush || this.direction == MoveDirection.UP || this.direction == MoveDirection.DOWN) {
-                return TurtleCommandResult.failure("Movement obstructed");
-            }
-
-            // Check there is space for all the pushable entities to be pushed
-            var list = oldWorld.getEntitiesOfClass(Entity.class, getBox(collision), x -> x != null && x.isAlive() && x.blocksBuilding);
-            for (var entity : list) {
-                var pushedBB = entity.getBoundingBox().move(
-                    direction.getStepX(),
-                    direction.getStepY(),
-                    direction.getStepZ()
-                );
-                if (!oldWorld.isUnobstructed(null, Shapes.create(pushedBB))) {
-                    return TurtleCommandResult.failure("Movement obstructed");
-                }
-            }
+        // Check there isn't an entity in the way.
+        var turtleShape = level.getBlockState(oldPosition).getCollisionShape(level, oldPosition)
+            .move(newPosition.getX(), newPosition.getY(), newPosition.getZ());
+        if (!level.isUnobstructed(null, turtleShape) && !canPushEntities(level, turtleShape.bounds())) {
+            return TurtleCommandResult.failure("Movement obstructed");
         }
 
         // Check fuel level
-        if (turtle.isFuelNeeded() && turtle.getFuelLevel() < 1) {
-            return TurtleCommandResult.failure("Out of fuel");
-        }
+        if (turtle.isFuelNeeded() && turtle.getFuelLevel() < 1) return TurtleCommandResult.failure("Out of fuel");
 
         // Move
-        if (!turtle.teleportTo(oldWorld, newPosition)) return TurtleCommandResult.failure("Movement failed");
+        if (!turtle.teleportTo(level, newPosition)) return TurtleCommandResult.failure("Movement failed");
 
         // Consume fuel
         turtle.consumeFuel(1);
@@ -114,9 +89,20 @@ public class TurtleMoveCommand implements TurtleCommand {
         return TurtleCommandResult.success();
     }
 
-    private static AABB getBox(VoxelShape shape) {
-        return shape.isEmpty() ? EMPTY_BOX : shape.bounds();
-    }
 
-    private static final AABB EMPTY_BOX = new AABB(0, 0, 0, 0, 0, 0);
+    /**
+     * Determine if all entities in the given bounds can be pushed by the turtle.
+     *
+     * @param level  The current level.
+     * @param bounds The bounding box.
+     * @return Whether all entities can be pushed.
+     */
+    private boolean canPushEntities(Level level, AABB bounds) {
+        if (!Config.turtlesCanPush) return false;
+
+        // Check there is space for all the pushable entities to be pushed
+        return level.getEntities((Entity) null, bounds, e -> e.isAlive()
+            && !e.isSpectator() && e.blocksBuilding && e.getPistonPushReaction() == PushReaction.IGNORE
+        ).isEmpty();
+    }
 }

projects/common/src/main/java/dan200/computercraft/shared/util/ComponentMap.java

@@ -1,66 +0,0 @@
-// SPDX-FileCopyrightText: 2024 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.util;
-
-import dan200.computercraft.api.component.ComputerComponent;
-import dan200.computercraft.core.metrics.MetricsObserver;
-
-import javax.annotation.Nullable;
-import java.util.HashMap;
-import java.util.Map;
-
-/**
- * An immutable map of components.
- */
-public final class ComponentMap {
-    public static final ComputerComponent<MetricsObserver> METRICS = ComputerComponent.create("computercraft", "metrics");
-
-    private static final ComponentMap EMPTY = new ComponentMap(Map.of());
-
-    private final Map<ComputerComponent<?>, Object> components;
-
-    private ComponentMap(Map<ComputerComponent<?>, Object> components) {
-        this.components = components;
-    }
-
-    @SuppressWarnings("unchecked")
-    public <T> @Nullable T get(ComputerComponent<T> component) {
-        return (T) components.get(component);
-    }
-
-    public static ComponentMap empty() {
-        return EMPTY;
-    }
-
-    public static Builder builder() {
-        return new Builder();
-    }
-
-    public static final class Builder {
-        private final Map<ComputerComponent<?>, Object> components = new HashMap<>();
-
-        private Builder() {
-        }
-
-        public <T> Builder add(ComputerComponent<T> component, T value) {
-            addImpl(component, value);
-            return this;
-        }
-
-        public Builder add(ComponentMap components) {
-            for (var component : components.components.entrySet()) addImpl(component.getKey(), component.getValue());
-            return this;
-        }
-
-        private void addImpl(ComputerComponent<?> component, Object value) {
-            if (components.containsKey(component)) throw new IllegalArgumentException(component + " is already set");
-            components.put(component, value);
-        }
-
-        public ComponentMap build() {
-            return new ComponentMap(Map.copyOf(components));
-        }
-    }
-}

projects/common/src/main/java/dan200/computercraft/shared/util/NBTUtil.java

@@ -62,125 +62,33 @@ public final class NBTUtil {
         return childTag != null && childTag.getId() == Tag.TAG_COMPOUND ? (CompoundTag) childTag : emptyTag();
     }
 
-    private static @Nullable Tag toNBTTag(@Nullable Object object) {
-        if (object == null) return null;
-        if (object instanceof Boolean) return ByteTag.valueOf((byte) ((boolean) (Boolean) object ? 1 : 0));
-        if (object instanceof Number) return DoubleTag.valueOf(((Number) object).doubleValue());
-        if (object instanceof String) return StringTag.valueOf(object.toString());
-        if (object instanceof Map<?, ?> m) {
-            var nbt = new CompoundTag();
-            var i = 0;
-            for (Map.Entry<?, ?> entry : m.entrySet()) {
-                var key = toNBTTag(entry.getKey());
-                var value = toNBTTag(entry.getKey());
-                if (key != null && value != null) {
-                    nbt.put("k" + i, key);
-                    nbt.put("v" + i, value);
-                    i++;
-                }
-            }
-            nbt.putInt("len", m.size());
-            return nbt;
-        }
-
-        return null;
-    }
-
-    public static @Nullable CompoundTag encodeObjects(@Nullable Object[] objects) {
-        if (objects == null || objects.length == 0) return null;
-
-        var nbt = new CompoundTag();
-        nbt.putInt("len", objects.length);
-        for (var i = 0; i < objects.length; i++) {
-            var child = toNBTTag(objects[i]);
-            if (child != null) nbt.put(Integer.toString(i), child);
-        }
-        return nbt;
-    }
-
-    private static @Nullable Object fromNBTTag(@Nullable Tag tag) {
-        if (tag == null) return null;
-        switch (tag.getId()) {
-            case Tag.TAG_BYTE:
-                return ((ByteTag) tag).getAsByte() > 0;
-            case Tag.TAG_DOUBLE:
-                return ((DoubleTag) tag).getAsDouble();
-            default:
-            case Tag.TAG_STRING:
-                return tag.getAsString();
-            case Tag.TAG_COMPOUND: {
-                var c = (CompoundTag) tag;
-                var len = c.getInt("len");
-                Map<Object, Object> map = new HashMap<>(len);
-                for (var i = 0; i < len; i++) {
-                    var key = fromNBTTag(c.get("k" + i));
-                    var value = fromNBTTag(c.get("v" + i));
-                    if (key != null && value != null) map.put(key, value);
-                }
-                return map;
-            }
-        }
-    }
-
     public static @Nullable Object toLua(@Nullable Tag tag) {
         if (tag == null) return null;
 
-        switch (tag.getId()) {
-            case Tag.TAG_BYTE:
-            case Tag.TAG_SHORT:
-            case Tag.TAG_INT:
-            case Tag.TAG_LONG:
-                return ((NumericTag) tag).getAsLong();
-            case Tag.TAG_FLOAT:
-            case Tag.TAG_DOUBLE:
-                return ((NumericTag) tag).getAsDouble();
-            case Tag.TAG_STRING: // String
-                return tag.getAsString();
-            case Tag.TAG_COMPOUND: { // Compound
+        return switch (tag.getId()) {
+            case Tag.TAG_BYTE, Tag.TAG_SHORT, Tag.TAG_INT, Tag.TAG_LONG -> ((NumericTag) tag).getAsLong();
+            case Tag.TAG_FLOAT, Tag.TAG_DOUBLE -> ((NumericTag) tag).getAsDouble();
+            case Tag.TAG_STRING -> tag.getAsString();
+            case Tag.TAG_COMPOUND -> {
                 var compound = (CompoundTag) tag;
                 Map<String, Object> map = new HashMap<>(compound.size());
                 for (var key : compound.getAllKeys()) {
                     var value = toLua(compound.get(key));
                     if (value != null) map.put(key, value);
                 }
-                return map;
+                yield map;
             }
-            case Tag.TAG_LIST: {
-                var list = (ListTag) tag;
-                List<Object> map = new ArrayList<>(list.size());
-                for (var value : list) map.add(toLua(value));
-                return map;
-            }
-            case Tag.TAG_BYTE_ARRAY: {
+            case Tag.TAG_LIST -> ((ListTag) tag).stream().map(NBTUtil::toLua).toList();
+            case Tag.TAG_BYTE_ARRAY -> {
                 var array = ((ByteArrayTag) tag).getAsByteArray();
                 List<Byte> map = new ArrayList<>(array.length);
                 for (var b : array) map.add(b);
-                return map;
+                yield map;
             }
-            case Tag.TAG_INT_ARRAY: {
-                var array = ((IntArrayTag) tag).getAsIntArray();
-                List<Integer> map = new ArrayList<>(array.length);
-                for (var j : array) map.add(j);
-                return map;
-            }
-
-            default:
-                return null;
-        }
-    }
-
-    public static @Nullable Object[] decodeObjects(CompoundTag tag) {
-        var len = tag.getInt("len");
-        if (len <= 0) return null;
-
-        var objects = new Object[len];
-        for (var i = 0; i < len; i++) {
-            var key = Integer.toString(i);
-            if (tag.contains(key)) {
-                objects[i] = fromNBTTag(tag.get(key));
-            }
-        }
-        return objects;
+            case Tag.TAG_INT_ARRAY -> Arrays.stream(((IntArrayTag) tag).getAsIntArray()).boxed().toList();
+            case Tag.TAG_LONG_ARRAY -> Arrays.stream(((LongArrayTag) tag).getAsLongArray()).boxed().toList();
+            default -> null;
+        };
     }
 
     @Nullable

projects/common/src/main/java/dan200/computercraft/shared/util/WorldUtil.java

@@ -29,9 +29,14 @@ import net.minecraft.world.phys.shapes.VoxelShape;
 import javax.annotation.Nullable;
 
 public final class WorldUtil {
+    @SuppressWarnings("deprecation")
     public static boolean isLiquidBlock(Level world, BlockPos pos) {
-        if (!world.isInWorldBounds(pos)) return false;
-        return world.getBlockState(pos).liquid();
+        return world.isInWorldBounds(pos) && world.getBlockState(pos).liquid();
+    }
+
+    @SuppressWarnings("deprecation")
+    public static boolean isEmptyBlock(BlockState state) {
+        return state.isAir() || state.liquid();
     }
 
     public static boolean isVecInside(VoxelShape shape, Vec3 vec) {

projects/common/src/test/java/dan200/computercraft/TestPlatformHelper.java

@@ -25,6 +25,7 @@ import net.minecraft.core.Direction;
 import net.minecraft.core.Registry;
 import net.minecraft.core.registries.BuiltInRegistries;
 import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.network.chat.Component;
 import net.minecraft.network.protocol.Packet;
 import net.minecraft.network.protocol.game.ClientGamePacketListener;
 import net.minecraft.network.protocol.game.ClientboundCustomPayloadPacket;
@@ -35,11 +36,11 @@ import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.tags.TagKey;
 import net.minecraft.world.Container;
 import net.minecraft.world.InteractionResult;
-import net.minecraft.world.MenuProvider;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.inventory.AbstractContainerMenu;
 import net.minecraft.world.inventory.CraftingContainer;
+import net.minecraft.world.inventory.MenuConstructor;
 import net.minecraft.world.inventory.MenuType;
 import net.minecraft.world.item.CreativeModeTab;
 import net.minecraft.world.item.Item;
@@ -140,7 +141,7 @@ public class TestPlatformHelper extends AbstractComputerCraftAPI implements Plat
     }
 
     @Override
-    public void openMenu(Player player, MenuProvider owner, ContainerData menu) {
+    public void openMenu(Player player, Component title, MenuConstructor menu, ContainerData data) {
         throw new UnsupportedOperationException("Cannot open menu inside tests");
     }
 

projects/common/src/testMod/java/dan200/computercraft/mixin/gametest/GameTestServerMixin.java

@@ -0,0 +1,51 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.mixin.gametest;
+
+import com.mojang.datafixers.DataFixer;
+import dan200.computercraft.gametest.core.TestHooks;
+import net.minecraft.gametest.framework.GameTestServer;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.Services;
+import net.minecraft.server.WorldStem;
+import net.minecraft.server.level.progress.ChunkProgressListenerFactory;
+import net.minecraft.server.packs.repository.PackRepository;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+
+import java.net.Proxy;
+import java.util.concurrent.locks.LockSupport;
+
+@Mixin(GameTestServer.class)
+abstract class GameTestServerMixin extends MinecraftServer {
+    GameTestServerMixin(Thread serverThread, LevelStorageSource.LevelStorageAccess storageSource, PackRepository packRepository, WorldStem worldStem, Proxy proxy, DataFixer fixerUpper, Services services, ChunkProgressListenerFactory progressListenerFactory) {
+        super(serverThread, storageSource, packRepository, worldStem, proxy, fixerUpper, services, progressListenerFactory);
+    }
+
+    /**
+     * Overwrite {@link GameTestServer#waitUntilNextTick()} to wait for all computers to finish executing.
+     * <p>
+     * This is a little dangerous (breaks async behaviour of computers), but it forces tests to be deterministic.
+     *
+     * @reason See above. This is only in the test mod, so no risk of collision.
+     * @author SquidDev.
+     */
+    @Overwrite
+    @Override
+    public void waitUntilNextTick() {
+        while (true) {
+            runAllTasks();
+            if (!haveTestsStarted() || TestHooks.areComputersIdle(this)) break;
+            LockSupport.parkNanos(100_000);
+        }
+    }
+
+    @Shadow
+    private boolean haveTestsStarted() {
+        throw new AssertionError("Stub.");
+    }
+}

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Component_Test.kt

@@ -0,0 +1,56 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.gametest
+
+import dan200.computercraft.gametest.api.assertNoPeripheral
+import dan200.computercraft.gametest.api.assertPeripheral
+import dan200.computercraft.gametest.api.immediate
+import dan200.computercraft.shared.ModRegistry
+import dan200.computercraft.shared.platform.ComponentAccess
+import net.minecraft.core.BlockPos
+import net.minecraft.core.Direction
+import net.minecraft.gametest.framework.GameTest
+import net.minecraft.gametest.framework.GameTestHelper
+import java.util.*
+
+/**
+ * Checks that we expose [ComponentAccess] for various blocks/block entities
+ */
+class Component_Test {
+    @GameTest(template = "default")
+    fun Peripheral(context: GameTestHelper) = context.immediate {
+        val pos = BlockPos(2, 2, 2)
+        // We fetch peripherals from the NORTH, as that is the default direction for modems. This is a bit of a hack,
+        // but avoids having to override the block state.
+        val side = Direction.NORTH
+
+        for ((block, type) in mapOf(
+            // Computers
+            ModRegistry.Blocks.COMPUTER_NORMAL to Optional.of("computer"),
+            ModRegistry.Blocks.COMPUTER_ADVANCED to Optional.of("computer"),
+            ModRegistry.Blocks.COMPUTER_COMMAND to Optional.empty(),
+            // Turtles
+            ModRegistry.Blocks.TURTLE_NORMAL to Optional.of("turtle"),
+            ModRegistry.Blocks.TURTLE_ADVANCED to Optional.of("turtle"),
+            // Peripherals
+            ModRegistry.Blocks.SPEAKER to Optional.of("speaker"),
+            ModRegistry.Blocks.DISK_DRIVE to Optional.of("drive"),
+            ModRegistry.Blocks.PRINTER to Optional.of("printer"),
+            ModRegistry.Blocks.MONITOR_NORMAL to Optional.of("monitor"),
+            ModRegistry.Blocks.MONITOR_ADVANCED to Optional.of("monitor"),
+            ModRegistry.Blocks.WIRELESS_MODEM_NORMAL to Optional.of("modem"),
+            ModRegistry.Blocks.WIRELESS_MODEM_ADVANCED to Optional.of("modem"),
+            ModRegistry.Blocks.WIRED_MODEM_FULL to Optional.of("modem"),
+            ModRegistry.Blocks.REDSTONE_RELAY to Optional.of("redstone_relay"),
+        )) {
+            context.setBlock(pos, block.get())
+            if (type.isPresent) {
+                context.assertPeripheral(pos, side, type.get())
+            } else {
+                context.assertNoPeripheral(pos, side)
+            }
+        }
+    }
+}

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Computer_Test.kt

@@ -95,17 +95,6 @@ class Computer_Test {
         }
     }
 
-    /**
-     * Check computers and turtles expose peripherals.
-     */
-    @GameTest
-    fun Computer_peripheral(context: GameTestHelper) = context.sequence {
-        thenExecute {
-            context.assertPeripheral(BlockPos(3, 2, 2), type = "computer")
-            context.assertPeripheral(BlockPos(1, 2, 2), type = "turtle")
-        }
-    }
-
     /**
      * Check chest peripherals are reattached with a new size.
      */

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/Turtle_Test.kt

@@ -642,6 +642,27 @@ class Turtle_Test {
         }
     }
 
+    /**
+     * Test turtles can push entities.
+     */
+    @GameTest
+    fun Move_push_entity(helper: GameTestHelper) = helper.sequence {
+        thenOnComputer { turtle.up().await().assertArrayEquals(true) }
+        thenIdle(9)
+        thenExecute {
+            // The turtle has moved up
+            helper.assertBlockPresent(ModRegistry.Blocks.TURTLE_NORMAL.get(), BlockPos(2, 3, 2))
+
+            // As has the villager
+            val pos = BlockPos(2, 4, 2)
+            helper.assertEntityPresent(EntityType.VILLAGER, pos)
+
+            val villager = helper.getEntity(EntityType.VILLAGER)
+            val expectedY = helper.absolutePos(pos).y - 0.125
+            if (villager.y < expectedY) helper.fail("Expected villager at y>=$expectedY, but at ${villager.y}", pos)
+        }
+    }
+
     /**
      * Test a turtle can attack an entity and capture its drops.
      */

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/api/TestExtensions.kt

@@ -127,6 +127,14 @@ fun GameTestHelper.sequence(run: GameTestSequence.() -> Unit) {
     sequence.thenSucceed()
 }
 
+/**
+ * Run a function immediately, and then succeed.
+ */
+fun GameTestHelper.immediate(run: () -> Unit) {
+    run()
+    succeed()
+}
+
 /**
  * A custom instance of [GameTestAssertPosException] which allows for longer error messages.
  */
@@ -232,15 +240,17 @@ private fun GameTestHelper.getPeripheralAt(pos: BlockPos, direction: Direction):
 
 fun GameTestHelper.assertPeripheral(pos: BlockPos, direction: Direction = Direction.UP, type: String) {
     val peripheral = getPeripheralAt(pos, direction)
+    val block = getBlockState(pos).block.name.string
     when {
-        peripheral == null -> fail("No peripheral at position", pos)
-        peripheral.type != type -> fail("Peripheral is of type ${peripheral.type}, expected $type", pos)
+        peripheral == null -> fail("No peripheral for '$block'", pos)
+        peripheral.type != type -> fail("Peripheral for '$block' is of type ${peripheral.type}, expected $type", pos)
     }
 }
 
 fun GameTestHelper.assertNoPeripheral(pos: BlockPos, direction: Direction = Direction.UP) {
     val peripheral = getPeripheralAt(pos, direction)
-    if (peripheral != null) fail("Expected no peripheral, got a ${peripheral.type}", pos)
+    val block = getBlockState(pos).block.name
+    if (peripheral != null) fail("Expected no peripheral for '$block', got a ${peripheral.type}", pos)
 }
 
 fun GameTestHelper.assertExactlyItems(vararg expected: ItemStack, message: String? = null) {

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/core/ManagedComputers.kt

@@ -36,6 +36,10 @@ object ManagedComputers : ILuaMachine.Factory {
     private val LOGGER = LoggerFactory.getLogger(ManagedComputers::class.java)
     private val computers: MutableMap<String, Queue<suspend LuaTaskContext.() -> Unit>> = mutableMapOf()
 
+    internal fun reset() {
+        computers.clear()
+    }
+
     internal fun enqueue(test: GameTestInfo, label: String, task: suspend LuaTaskContext.() -> Unit): Monitor {
         val monitor = Monitor(test, label)
         computers.computeIfAbsent(label) { ConcurrentLinkedDeque() }.add {

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/core/TestHooks.kt

@@ -5,6 +5,8 @@
 package dan200.computercraft.gametest.core
 
 import dan200.computercraft.api.ComputerCraftAPI
+import dan200.computercraft.core.ComputerContext
+import dan200.computercraft.core.computer.computerthread.ComputerThread
 import dan200.computercraft.gametest.*
 import dan200.computercraft.gametest.api.ClientGameTest
 import dan200.computercraft.gametest.api.TestTags
@@ -23,6 +25,8 @@ import net.minecraft.world.phys.Vec3
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 import java.io.File
+import java.lang.invoke.MethodHandle
+import java.lang.invoke.MethodHandles
 import java.lang.reflect.InvocationTargetException
 import java.lang.reflect.Method
 import java.lang.reflect.Modifier
@@ -69,6 +73,8 @@ object TestHooks {
         LOG.info("Cleaning up after last run")
         GameTestRunner.clearAllTests(server.overworld(), BlockPos(0, -60, 0), GameTestTicker.SINGLETON, 200)
 
+        ManagedComputers.reset()
+
         // Delete server context and add one with a mutable machine factory. This allows us to set the factory for
         // specific test batches without having to reset all computers.
         for (computer in ServerContext.get(server).registry().computers) {
@@ -80,7 +86,11 @@ object TestHooks {
         CCTestCommand.importFiles(server)
     }
 
+    @JvmStatic
+    fun areComputersIdle(server: MinecraftServer) = ComputerThreadReflection.isFullyIdle(ServerContext.get(server))
+
     private val testClasses = listOf(
+        Component_Test::class.java,
         Computer_Test::class.java,
         CraftOs_Test::class.java,
         Disk_Drive_Test::class.java,
@@ -116,14 +126,6 @@ object TestHooks {
         }
     }
 
-    private val isCi = System.getenv("CI") != null
-
-    /**
-     * Adjust the timeout of a test. This makes it 1.5 times longer when run under CI, as CI servers are less powerful
-     * than our own.
-     */
-    private fun adjustTimeout(timeout: Int): Int = if (isCi) timeout + (timeout / 2) else timeout
-
     private fun registerTest(testClass: Class<*>, method: Method, fallbackRegister: Consumer<Method>) {
         val className = testClass.simpleName.lowercase()
         val testName = className + "." + method.name.lowercase()
@@ -135,7 +137,7 @@ object TestHooks {
                 TestFunction(
                     testInfo.batch, testName, testInfo.template.ifEmpty { testName },
                     StructureUtils.getRotationForRotationSteps(testInfo.rotationSteps),
-                    adjustTimeout(testInfo.timeoutTicks),
+                    testInfo.timeoutTicks,
                     testInfo.setupTicks,
                     testInfo.required, testInfo.requiredSuccesses, testInfo.attempts,
                 ) { value -> safeInvoke(method, value) },
@@ -152,7 +154,7 @@ object TestHooks {
                     testName,
                     testName,
                     testInfo.template.ifEmpty { testName },
-                    adjustTimeout(testInfo.timeoutTicks),
+                    testInfo.timeoutTicks,
                     0,
                     true,
                 ) { value -> safeInvoke(method, value) },
@@ -200,3 +202,31 @@ object TestHooks {
         return false
     }
 }
+
+/**
+ * Nasty reflection to determine if computers are fully idle.
+ *
+ * This is horribly nasty, and should not be used as a model for any production code!
+ *
+ * @see [ComputerThread.isFullyIdle]
+ * @see [dan200.computercraft.mixin.gametest.GameTestServerMixin]
+ */
+private object ComputerThreadReflection {
+    private val lookup = MethodHandles.lookup()
+
+    @JvmField
+    val computerContext: MethodHandle = lookup.unreflectGetter(
+        ServerContext::class.java.getDeclaredField("context").also { it.isAccessible = true },
+    )
+
+    @JvmField
+    val isFullyIdle: MethodHandle = lookup.unreflect(
+        ComputerThread::class.java.getDeclaredMethod("isFullyIdle").also { it.isAccessible = true },
+    )
+
+    fun isFullyIdle(context: ServerContext): Boolean {
+        val computerContext = computerContext.invokeExact(context) as ComputerContext
+        val computerThread = computerContext.computerScheduler() as ComputerThread
+        return isFullyIdle.invokeExact(computerThread) as Boolean
+    }
+}

projects/common/src/testMod/kotlin/dan200/computercraft/gametest/core/TestReporters.kt

@@ -35,7 +35,7 @@ class MultiTestReporter(private val reporters: List<TestReporter>) : TestReporte
  * Reports tests to a JUnit XML file. This is equivalent to [JUnitLikeTestReporter], except it ensures the destination
  * directory exists.
  */
-class JunitTestReporter constructor(destination: File) : JUnitLikeTestReporter(destination) {
+class JunitTestReporter(destination: File) : JUnitLikeTestReporter(destination) {
     override fun save(file: File) {
         try {
             Files.createDirectories(file.toPath().parent)

projects/common/src/testMod/resources/computercraft-gametest.mixins.json

@@ -11,6 +11,7 @@
         "GameTestInfoAccessor",
         "GameTestSequenceAccessor",
         "GameTestSequenceMixin",
+        "GameTestServerMixin",
         "TestCommandAccessor"
     ],
     "client": [

projects/common/src/testMod/resources/data/cctest/structures/turtle_test.move_push_entity.snbt

@@ -1,5 +1,5 @@
 {
-    DataVersion: 2975,
+    DataVersion: 3465,
     size: [5, 5, 5],
     data: [
         {pos: [0, 0, 0], state: "minecraft:polished_andesite"},
@@ -33,19 +33,19 @@
         {pos: [0, 1, 3], state: "minecraft:air"},
         {pos: [0, 1, 4], state: "minecraft:air"},
         {pos: [1, 1, 0], state: "minecraft:air"},
-        {pos: [1, 1, 1], state: "minecraft:air"},
-        {pos: [1, 1, 2], state: "computercraft:turtle_advanced{facing:south,waterlogged:false}", nbt: {Fuel: 0, Items: [], On: 0b, Owner: {LowerId: -6876936588741668278L, Name: "Dev", UpperId: 4039158846114182220L}, Slot: 0, id: "computercraft:turtle_advanced"}},
-        {pos: [1, 1, 3], state: "minecraft:air"},
+        {pos: [1, 1, 1], state: "minecraft:white_stained_glass"},
+        {pos: [1, 1, 2], state: "minecraft:white_stained_glass"},
+        {pos: [1, 1, 3], state: "minecraft:white_stained_glass"},
         {pos: [1, 1, 4], state: "minecraft:air"},
         {pos: [2, 1, 0], state: "minecraft:air"},
-        {pos: [2, 1, 1], state: "minecraft:air"},
-        {pos: [2, 1, 2], state: "minecraft:air"},
-        {pos: [2, 1, 3], state: "minecraft:air"},
+        {pos: [2, 1, 1], state: "minecraft:white_stained_glass"},
+        {pos: [2, 1, 2], state: "computercraft:turtle_normal{facing:west,waterlogged:false}", nbt: {ComputerId: 1, Label: "turtle_test.move_push_entity", Fuel: 80, Items: [], On: 1b, Slot: 0, id: "computercraft:turtle_normal"}},
+        {pos: [2, 1, 3], state: "minecraft:white_stained_glass"},
         {pos: [2, 1, 4], state: "minecraft:air"},
         {pos: [3, 1, 0], state: "minecraft:air"},
-        {pos: [3, 1, 1], state: "minecraft:air"},
-        {pos: [3, 1, 2], state: "computercraft:computer_advanced{facing:north,state:off}", nbt: {On: 0b, id: "computercraft:computer_advanced"}},
-        {pos: [3, 1, 3], state: "minecraft:air"},
+        {pos: [3, 1, 1], state: "minecraft:white_stained_glass"},
+        {pos: [3, 1, 2], state: "minecraft:white_stained_glass"},
+        {pos: [3, 1, 3], state: "minecraft:white_stained_glass"},
         {pos: [3, 1, 4], state: "minecraft:air"},
         {pos: [4, 1, 0], state: "minecraft:air"},
         {pos: [4, 1, 1], state: "minecraft:air"},
@@ -58,19 +58,19 @@
         {pos: [0, 2, 3], state: "minecraft:air"},
         {pos: [0, 2, 4], state: "minecraft:air"},
         {pos: [1, 2, 0], state: "minecraft:air"},
-        {pos: [1, 2, 1], state: "minecraft:air"},
-        {pos: [1, 2, 2], state: "minecraft:air"},
-        {pos: [1, 2, 3], state: "minecraft:air"},
+        {pos: [1, 2, 1], state: "minecraft:white_stained_glass"},
+        {pos: [1, 2, 2], state: "minecraft:white_stained_glass"},
+        {pos: [1, 2, 3], state: "minecraft:white_stained_glass"},
         {pos: [1, 2, 4], state: "minecraft:air"},
         {pos: [2, 2, 0], state: "minecraft:air"},
-        {pos: [2, 2, 1], state: "minecraft:air"},
+        {pos: [2, 2, 1], state: "minecraft:white_stained_glass"},
         {pos: [2, 2, 2], state: "minecraft:air"},
-        {pos: [2, 2, 3], state: "minecraft:air"},
+        {pos: [2, 2, 3], state: "minecraft:white_stained_glass"},
         {pos: [2, 2, 4], state: "minecraft:air"},
         {pos: [3, 2, 0], state: "minecraft:air"},
-        {pos: [3, 2, 1], state: "minecraft:air"},
-        {pos: [3, 2, 2], state: "minecraft:air"},
-        {pos: [3, 2, 3], state: "minecraft:air"},
+        {pos: [3, 2, 1], state: "minecraft:white_stained_glass"},
+        {pos: [3, 2, 2], state: "minecraft:white_stained_glass"},
+        {pos: [3, 2, 3], state: "minecraft:white_stained_glass"},
         {pos: [3, 2, 4], state: "minecraft:air"},
         {pos: [4, 2, 0], state: "minecraft:air"},
         {pos: [4, 2, 1], state: "minecraft:air"},
@@ -83,19 +83,19 @@
         {pos: [0, 3, 3], state: "minecraft:air"},
         {pos: [0, 3, 4], state: "minecraft:air"},
         {pos: [1, 3, 0], state: "minecraft:air"},
-        {pos: [1, 3, 1], state: "minecraft:air"},
-        {pos: [1, 3, 2], state: "minecraft:air"},
-        {pos: [1, 3, 3], state: "minecraft:air"},
+        {pos: [1, 3, 1], state: "minecraft:white_stained_glass"},
+        {pos: [1, 3, 2], state: "minecraft:white_stained_glass"},
+        {pos: [1, 3, 3], state: "minecraft:white_stained_glass"},
         {pos: [1, 3, 4], state: "minecraft:air"},
         {pos: [2, 3, 0], state: "minecraft:air"},
-        {pos: [2, 3, 1], state: "minecraft:air"},
+        {pos: [2, 3, 1], state: "minecraft:white_stained_glass"},
         {pos: [2, 3, 2], state: "minecraft:air"},
-        {pos: [2, 3, 3], state: "minecraft:air"},
+        {pos: [2, 3, 3], state: "minecraft:white_stained_glass"},
         {pos: [2, 3, 4], state: "minecraft:air"},
         {pos: [3, 3, 0], state: "minecraft:air"},
-        {pos: [3, 3, 1], state: "minecraft:air"},
-        {pos: [3, 3, 2], state: "minecraft:air"},
-        {pos: [3, 3, 3], state: "minecraft:air"},
+        {pos: [3, 3, 1], state: "minecraft:white_stained_glass"},
+        {pos: [3, 3, 2], state: "minecraft:white_stained_glass"},
+        {pos: [3, 3, 3], state: "minecraft:white_stained_glass"},
         {pos: [3, 3, 4], state: "minecraft:air"},
         {pos: [4, 3, 0], state: "minecraft:air"},
         {pos: [4, 3, 1], state: "minecraft:air"},
@@ -108,19 +108,19 @@
         {pos: [0, 4, 3], state: "minecraft:air"},
         {pos: [0, 4, 4], state: "minecraft:air"},
         {pos: [1, 4, 0], state: "minecraft:air"},
-        {pos: [1, 4, 1], state: "minecraft:air"},
-        {pos: [1, 4, 2], state: "minecraft:air"},
-        {pos: [1, 4, 3], state: "minecraft:air"},
+        {pos: [1, 4, 1], state: "minecraft:white_stained_glass"},
+        {pos: [1, 4, 2], state: "minecraft:white_stained_glass"},
+        {pos: [1, 4, 3], state: "minecraft:white_stained_glass"},
         {pos: [1, 4, 4], state: "minecraft:air"},
         {pos: [2, 4, 0], state: "minecraft:air"},
-        {pos: [2, 4, 1], state: "minecraft:air"},
+        {pos: [2, 4, 1], state: "minecraft:white_stained_glass"},
         {pos: [2, 4, 2], state: "minecraft:air"},
-        {pos: [2, 4, 3], state: "minecraft:air"},
+        {pos: [2, 4, 3], state: "minecraft:white_stained_glass"},
         {pos: [2, 4, 4], state: "minecraft:air"},
         {pos: [3, 4, 0], state: "minecraft:air"},
-        {pos: [3, 4, 1], state: "minecraft:air"},
-        {pos: [3, 4, 2], state: "minecraft:air"},
-        {pos: [3, 4, 3], state: "minecraft:air"},
+        {pos: [3, 4, 1], state: "minecraft:white_stained_glass"},
+        {pos: [3, 4, 2], state: "minecraft:white_stained_glass"},
+        {pos: [3, 4, 3], state: "minecraft:white_stained_glass"},
         {pos: [3, 4, 4], state: "minecraft:air"},
         {pos: [4, 4, 0], state: "minecraft:air"},
         {pos: [4, 4, 1], state: "minecraft:air"},
@@ -128,11 +128,13 @@
         {pos: [4, 4, 3], state: "minecraft:air"},
         {pos: [4, 4, 4], state: "minecraft:air"}
     ],
-    entities: [],
+    entities: [
+        {blockPos: [2, 1, 2], pos: [2.5d, 1.875d, 2.5d], nbt: {AbsorptionAmount: 0.0f, Age: 0, Air: 300s, ArmorDropChances: [0.085f, 0.085f, 0.085f, 0.085f], ArmorItems: [{}, {}, {}, {}], Attributes: [{Base: 0.5d, Name: "minecraft:generic.movement_speed"}, {Base: 48.0d, Modifiers: [{Amount: -0.01165046535152748d, Name: "Random spawn bonus", Operation: 1, UUID: [I; 1412502412, 1522745411, -1211155694, 2103054347]}], Name: "minecraft:generic.follow_range"}], Brain: {memories: {}}, CanPickUpLoot: 1b, DeathTime: 0s, FallDistance: 0.0f, FallFlying: 0b, Fire: -1s, FoodLevel: 0b, ForcedAge: 0, Gossips: [], HandDropChances: [0.085f, 0.085f], HandItems: [{}, {}], Health: 20.0f, HurtByTimestamp: 0, HurtTime: 0s, Inventory: [], Invulnerable: 0b, LastGossipDecay: 52357L, LastRestock: 0L, LeftHanded: 0b, Motion: [0.0d, -0.0784000015258789d, 0.0d], OnGround: 1b, PersistenceRequired: 0b, PortalCooldown: 0, Pos: [-33.5d, 58.875d, -21.5d], RestocksToday: 0, Rotation: [-102.704926f, 0.0f], UUID: [I; 164071932, -867285780, -1817215456, -2129864016], VillagerData: {level: 1, profession: "minecraft:none", type: "minecraft:desert"}, Xp: 0, id: "minecraft:villager"}}
+    ],
     palette: [
         "minecraft:polished_andesite",
+        "minecraft:white_stained_glass",
         "minecraft:air",
-        "computercraft:turtle_advanced{facing:south,waterlogged:false}",
-        "computercraft:computer_advanced{facing:north,state:off}"
+        "computercraft:turtle_normal{facing:west,waterlogged:false}"
     ]
 }

projects/core/src/main/java/dan200/computercraft/core/apis/http/websocket/WebsocketHandle.java

@@ -69,7 +69,7 @@ public class WebsocketHandle {
      * Send a websocket message to the connected server.
      *
      * @param message The message to send.
-     * @param binary  Whether this message should be treated as a
+     * @param binary  Whether this message should be treated as a binary message.
      * @throws LuaException If the message is too large.
      * @throws LuaException If the websocket has been closed.
      * @cc.changed 1.81.0 Added argument for binary mode.

projects/core/src/main/java/dan200/computercraft/core/computer/Computer.java

@@ -31,7 +31,7 @@ import java.util.concurrent.atomic.AtomicLong;
  * <li>Passes main thread tasks to the {@link MainThreadScheduler.Executor}.</li>
  * </ul>
  */
-public class Computer {
+public class Computer implements ComputerEvents.Receiver {
     private static final int START_DELAY = 50;
 
     // Various properties of the computer
@@ -114,6 +114,7 @@ public class Computer {
         executor.queueStop(false, true);
     }
 
+    @Override
     public void queueEvent(String event, @Nullable Object[] args) {
         executor.queueEvent(event, args);
     }

projects/core/src/main/java/dan200/computercraft/core/computer/ComputerEvents.java

@@ -0,0 +1,72 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.core.computer;
+
+import dan200.computercraft.core.util.StringUtil;
+
+import javax.annotation.Nullable;
+import java.nio.ByteBuffer;
+
+/**
+ * Built-in events that can be queued on a computer.
+ */
+public final class ComputerEvents {
+    private ComputerEvents() {
+    }
+
+    public static void keyDown(Receiver receiver, int key, boolean repeat) {
+        receiver.queueEvent("key", new Object[]{ key, repeat });
+    }
+
+    public static void keyUp(Receiver receiver, int key) {
+        receiver.queueEvent("key_up", new Object[]{ key });
+    }
+
+    /**
+     * Type a character on the computer.
+     *
+     * @param receiver The computer to queue the event on.
+     * @param chr      The character to type.
+     * @see StringUtil#isTypableChar(byte)
+     */
+    public static void charTyped(Receiver receiver, byte chr) {
+        receiver.queueEvent("char", new Object[]{ new byte[]{ chr } });
+    }
+
+    /**
+     * Paste a string.
+     *
+     * @param receiver The computer to queue the event on.
+     * @param contents The string to paste.
+     * @see StringUtil#getClipboardString(String)
+     */
+    public static void paste(Receiver receiver, ByteBuffer contents) {
+        receiver.queueEvent("paste", new Object[]{ contents });
+    }
+
+    public static void mouseClick(Receiver receiver, int button, int x, int y) {
+        receiver.queueEvent("mouse_click", new Object[]{ button, x, y });
+    }
+
+    public static void mouseUp(Receiver receiver, int button, int x, int y) {
+        receiver.queueEvent("mouse_up", new Object[]{ button, x, y });
+    }
+
+    public static void mouseDrag(Receiver receiver, int button, int x, int y) {
+        receiver.queueEvent("mouse_drag", new Object[]{ button, x, y });
+    }
+
+    public static void mouseScroll(Receiver receiver, int direction, int x, int y) {
+        receiver.queueEvent("mouse_scroll", new Object[]{ direction, x, y });
+    }
+
+    /**
+     * An object that can receive computer events.
+     */
+    @FunctionalInterface
+    public interface Receiver {
+        void queueEvent(String event, @Nullable Object[] arguments);
+    }
+}

projects/core/src/main/java/dan200/computercraft/core/computer/computerthread/ComputerThread.java

@@ -433,6 +433,16 @@ public final class ComputerThread implements ComputerScheduler {
         return computerQueueSize() > idleWorkers.get();
     }
 
+    /**
+     * Determine if no work is queued, and all workers are idle.
+     *
+     * @return If the threads are fully idle.
+     */
+    @VisibleForTesting
+    boolean isFullyIdle() {
+        return computerQueueSize() == 0 && idleWorkers.get() >= workerCount();
+    }
+
     private void workerFinished(WorkerThread worker) {
         // We should only shut down a worker once! This should only happen if we fail to abort a worker and then the
         // worker finishes normally.

projects/core/src/main/java/dan200/computercraft/core/lua/CobaltLuaMachine.java

@@ -11,6 +11,7 @@ import dan200.computercraft.api.lua.ILuaFunction;
 import dan200.computercraft.core.CoreConfig;
 import dan200.computercraft.core.Logging;
 import dan200.computercraft.core.computer.TimeoutState;
+import dan200.computercraft.core.lua.errorinfo.ErrorInfoLib;
 import dan200.computercraft.core.methods.LuaMethod;
 import dan200.computercraft.core.methods.MethodSupplier;
 import dan200.computercraft.core.util.LuaUtil;
@@ -77,6 +78,7 @@ public class CobaltLuaMachine implements ILuaMachine {
             var globals = state.globals();
             CoreLibraries.debugGlobals(state);
             Bit32Lib.add(state, globals);
+            ErrorInfoLib.add(state);
             globals.rawset("_HOST", ValueFactory.valueOf(environment.hostString()));
             globals.rawset("_CC_DEFAULT_SETTINGS", ValueFactory.valueOf(CoreConfig.defaultComputerSettings));
 

projects/core/src/main/java/dan200/computercraft/core/lua/errorinfo/DebugHelpers.java

@@ -0,0 +1,64 @@
+// SPDX-FileCopyrightText: 2009-2011 Luaj.org, 2015-2020 SquidDev
+//
+// SPDX-License-Identifier: MIT
+
+package dan200.computercraft.core.lua.errorinfo;
+
+import org.squiddev.cobalt.Prototype;
+
+import static org.squiddev.cobalt.Lua.*;
+
+/**
+ * Extracted parts of Cobalt's {@link org.squiddev.cobalt.debug.DebugHelpers}.
+ */
+final class DebugHelpers {
+    private DebugHelpers() {
+    }
+
+    private static int filterPc(int pc, int jumpTarget) {
+        return pc < jumpTarget ? -1 : pc;
+    }
+
+    /**
+     * Find the PC where a register was last set.
+     * <p>
+     * This makes some assumptions about the structure of the bytecode, namely that there are no back edges within the
+     * CFG. As a result, this is only valid for temporary values, and not locals.
+     *
+     * @param pt     The function prototype.
+     * @param lastPc The PC to work back from.
+     * @param reg    The register.
+     * @return The last instruction where the register was set, or {@code -1} if not defined.
+     */
+    static int findSetReg(Prototype pt, int lastPc, int reg) {
+        var lastInsn = -1; // Last instruction that changed "reg";
+        var jumpTarget = 0; // Any code before this address is conditional
+
+        for (var pc = 0; pc < lastPc; pc++) {
+            var i = pt.code[pc];
+            var op = GET_OPCODE(i);
+            var a = GETARG_A(i);
+            switch (op) {
+                case OP_LOADNIL -> {
+                    var b = GETARG_B(i);
+                    if (a <= reg && reg <= a + b) lastInsn = filterPc(pc, jumpTarget);
+                }
+                case OP_TFORCALL -> {
+                    if (a >= a + 2) lastInsn = filterPc(pc, jumpTarget);
+                }
+                case OP_CALL, OP_TAILCALL -> {
+                    if (reg >= a) lastInsn = filterPc(pc, jumpTarget);
+                }
+                case OP_JMP -> {
+                    var dest = pc + 1 + GETARG_sBx(i);
+                    // If jump is forward and doesn't skip lastPc, update jump target
+                    if (pc < dest && dest <= lastPc && dest > jumpTarget) jumpTarget = dest;
+                }
+                default -> {
+                    if (testAMode(op) && reg == a) lastInsn = filterPc(pc, jumpTarget);
+                }
+            }
+        }
+        return lastInsn;
+    }
+}

projects/core/src/main/java/dan200/computercraft/core/lua/errorinfo/ErrorInfoLib.java

@@ -0,0 +1,222 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.core.lua.errorinfo;
+
+import com.google.common.annotations.VisibleForTesting;
+import org.squiddev.cobalt.*;
+import org.squiddev.cobalt.debug.DebugFrame;
+import org.squiddev.cobalt.function.LuaFunction;
+import org.squiddev.cobalt.function.RegisteredFunction;
+
+import javax.annotation.Nullable;
+import java.util.Objects;
+
+import static org.squiddev.cobalt.Lua.*;
+import static org.squiddev.cobalt.debug.DebugFrame.FLAG_ANY_HOOK;
+
+/**
+ * Provides additional info about an error.
+ * <p>
+ * This is currently an internal and deeply unstable module. It's not clear if doing this via bytecode (rather than an
+ * AST) is the correct approach and/or, what the correct design is.
+ */
+public class ErrorInfoLib {
+    private static final int MAX_DEPTH = 8;
+
+    private static final RegisteredFunction[] functions = new RegisteredFunction[]{
+        RegisteredFunction.ofV("info_for_nil", ErrorInfoLib::getInfoForNil),
+    };
+
+    public static void add(LuaState state) throws LuaError {
+        state.registry().getSubTable(Constants.LOADED).rawset("cc.internal.error_info", RegisteredFunction.bind(functions));
+    }
+
+    private static Varargs getInfoForNil(LuaState state, Varargs args) throws LuaError {
+        var thread = args.arg(1).checkThread();
+        var level = args.arg(2).checkInteger();
+
+        var context = getInfoForNil(state, thread, level);
+        return context == null ? Constants.NIL : ValueFactory.varargsOf(
+            ValueFactory.valueOf(context.op()), ValueFactory.valueOf(context.source().isGlobal()),
+            context.source().table(), context.source().key()
+        );
+    }
+
+    /**
+     * Get some additional information about an {@code attempt to $OP (a nil value)} error. This often occurs as a
+     * result of a misspelled local, global or table index, and so we attempt to detect those cases.
+     *
+     * @param state  The current Lua state.
+     * @param thread The thread which has errored.
+     * @param level  The level where the error occurred. We currently expect this to always be 0.
+     * @return Some additional information about the error, where available.
+     */
+    @VisibleForTesting
+    static @Nullable NilInfo getInfoForNil(LuaState state, LuaThread thread, int level) {
+        var frame = thread.getDebugState().getFrame(level);
+        if (frame == null || frame.closure == null || (frame.flags & FLAG_ANY_HOOK) != 0) return null;
+
+        var prototype = frame.closure.getPrototype();
+        var pc = frame.pc;
+        var insn = prototype.code[pc];
+
+        // Find what operation we're doing that errored.
+        return switch (GET_OPCODE(insn)) {
+            case OP_CALL, OP_TAILCALL ->
+                NilInfo.of("call", resolveValueSource(state, frame, prototype, pc, GETARG_A(insn), 0));
+            case OP_GETTABLE, OP_SETTABLE, OP_SELF ->
+                NilInfo.of("index", resolveValueSource(state, frame, prototype, pc, GETARG_A(insn), 0));
+            default -> null;
+        };
+    }
+
+    /**
+     * Information about an {@code attempt to $OP (a nil value)} error.
+     *
+     * @param op     The operation we tried to perform.
+     * @param source The expression that resulted in a nil value.
+     */
+    @VisibleForTesting
+    record NilInfo(String op, ValueSource source) {
+        public static @Nullable NilInfo of(String op, @Nullable ValueSource values) {
+            return values == null ? null : new NilInfo(op, values);
+        }
+    }
+
+    /**
+     * A partially-reconstructed Lua expression. This currently only is used for table indexing ({@code table[key]}.
+     *
+     * @param isGlobal Whether this is a global table access. This is a best-effort guess, and does not distinguish between
+     *                 {@code foo} and {@code _ENV.foo}.
+     * @param table    The table being indexed.
+     * @param key      The key we tried to index.
+     */
+    @VisibleForTesting
+    record ValueSource(boolean isGlobal, LuaValue table, LuaString key) {
+    }
+
+    /**
+     * Attempt to partially reconstruct a Lua expression from the current debug state.
+     *
+     * @param state     The current Lua state.
+     * @param frame     The current debug frame.
+     * @param prototype The current function.
+     * @param pc        The current program counter.
+     * @param register  The register where this value was stored.
+     * @param depth     The current depth. Starts at 0, and aborts once reaching {@link #MAX_DEPTH}.
+     * @return The reconstructed expression, or {@code null} if not available.
+     */
+    @SuppressWarnings("NullTernary")
+    private static @Nullable ValueSource resolveValueSource(LuaState state, DebugFrame frame, Prototype prototype, int pc, int register, int depth) {
+        if (depth > MAX_DEPTH) return null;
+        if (prototype.getLocalName(register + 1, pc) != null) return null;
+
+        // Find where this register was set. If unknown, then abort.
+        pc = DebugHelpers.findSetReg(prototype, pc, register);
+        if (pc == -1) return null;
+
+        var insn = prototype.code[pc];
+        return switch (GET_OPCODE(insn)) {
+            case OP_MOVE -> {
+                var a = GETARG_A(insn);
+                var b = GETARG_B(insn); // move from `b' to `a'
+                yield b < a ? resolveValueSource(state, frame, prototype, pc, register, depth + 1) : null; // Resolve 'b' .
+            }
+            case OP_GETTABUP, OP_GETTABLE, OP_SELF -> {
+                var tableIndex = GETARG_B(insn);
+                var keyIndex = GETARG_C(insn);
+                // We're only interested in expressions of the form "foo.bar". Showing a "did you mean" hint for
+                // "foo[i]" isn't very useful!
+                if (!ISK(keyIndex)) yield null;
+
+                var key = prototype.constants[INDEXK(keyIndex)];
+                if (key.type() != Constants.TSTRING) yield null;
+
+                var table = GET_OPCODE(insn) == OP_GETTABUP
+                    ? frame.closure.getUpvalue(tableIndex).getValue()
+                    : evaluate(state, frame, prototype, pc, tableIndex, depth);
+                if (table == null) yield null;
+
+                var isGlobal = GET_OPCODE(insn) == OP_GETTABUP && Objects.equals(prototype.getUpvalueName(tableIndex), Constants.ENV);
+                yield new ValueSource(isGlobal, table, (LuaString) key);
+            }
+            default -> null;
+        };
+    }
+
+    /**
+     * Attempt to reconstruct the value of a register.
+     *
+     * @param state     The current Lua state.
+     * @param frame     The current debug frame.
+     * @param prototype The current function
+     * @param pc        The PC to evaluate at.
+     * @param register  The register to evaluate.
+     * @param depth     The current depth. Starts at 0, and aborts once reaching {@link #MAX_DEPTH}.
+     * @return The reconstructed value, or {@code null} if unavailable.
+     */
+    @SuppressWarnings("NullTernary")
+    private static @Nullable LuaValue evaluate(LuaState state, DebugFrame frame, Prototype prototype, int pc, int register, int depth) {
+        if (depth >= MAX_DEPTH) return null;
+
+        // If this is a local, then return its contents.
+        if (prototype.getLocalName(register + 1, pc) != null) return frame.stack[register];
+
+        // Otherwise find where this register was set. If unknown, then abort.
+        pc = DebugHelpers.findSetReg(prototype, pc, register);
+        if (pc == -1) return null;
+
+        var insn = prototype.code[pc];
+        var opcode = GET_OPCODE(insn);
+        return switch (opcode) {
+            case OP_MOVE -> {
+                var a = GETARG_A(insn);
+                var b = GETARG_B(insn); // move from `b' to `a'
+                yield b < a ? evaluate(state, frame, prototype, pc, register, depth + 1) : null; // Resolve 'b'.
+            }
+            // Load constants
+            case OP_LOADK -> prototype.constants[GETARG_Bx(insn)];
+            case OP_LOADKX -> prototype.constants[GETARG_Ax(prototype.code[pc + 1])];
+            case OP_LOADBOOL -> GETARG_B(insn) == 0 ? Constants.FALSE : Constants.TRUE;
+            case OP_LOADNIL -> Constants.NIL;
+            // Upvalues and tables.
+            case OP_GETUPVAL -> frame.closure.getUpvalue(GETARG_B(insn)).getValue();
+            case OP_GETTABLE, OP_GETTABUP -> {
+                var table = opcode == OP_GETTABUP
+                    ? frame.closure.getUpvalue(GETARG_B(insn)).getValue()
+                    : evaluate(state, frame, prototype, pc, GETARG_B(insn), depth + 1);
+                if (table == null) yield null;
+
+                var key = evaluateK(state, frame, prototype, pc, GETARG_C(insn), depth + 1);
+                yield key == null ? null : safeIndex(state, table, key);
+            }
+            default -> null;
+        };
+    }
+
+    private static @Nullable LuaValue evaluateK(LuaState state, DebugFrame frame, Prototype prototype, int pc, int registerOrConstant, int depth) {
+        return ISK(registerOrConstant) ? prototype.constants[INDEXK(registerOrConstant)] : evaluate(state, frame, prototype, pc, registerOrConstant, depth + 1);
+    }
+
+    private static @Nullable LuaValue safeIndex(LuaState state, LuaValue table, LuaValue key) {
+        var loop = 0;
+        do {
+            LuaValue metatable;
+            if (table instanceof LuaTable tbl) {
+                var res = tbl.rawget(key);
+                if (!res.isNil() || (metatable = tbl.metatag(state, CachedMetamethod.INDEX)).isNil()) return res;
+            } else if ((metatable = table.metatag(state, CachedMetamethod.INDEX)).isNil()) {
+                return null;
+            }
+
+            if (metatable instanceof LuaFunction) return null;
+
+            table = metatable;
+        }
+        while (++loop < Constants.MAXTAGLOOP);
+
+        return null;
+    }
+}

projects/core/src/main/java/dan200/computercraft/core/util/StringUtil.java

@@ -4,52 +4,118 @@
 
 package dan200.computercraft.core.util;
 
+import dan200.computercraft.core.computer.ComputerEvents;
+
+import java.nio.ByteBuffer;
+
 public final class StringUtil {
+    public static final int MAX_PASTE_LENGTH = 512;
+
     private StringUtil() {
     }
 
-    private static boolean isAllowed(char c) {
-        return (c >= ' ' && c <= '~') || (c >= 161 && c <= 172) || (c >= 174 && c <= 255);
-    }
-
-    private static String removeSpecialCharacters(String text, int length) {
-        var builder = new StringBuilder(length);
-        for (var i = 0; i < length; i++) {
-            var c = text.charAt(i);
-            builder.append(isAllowed(c) ? c : '?');
+    /**
+     * Convert a Unicode character to a terminal one.
+     *
+     * @param chr The Unicode character.
+     * @return The terminal character. This is either in the range [0, 255] (if a valid character) or {@code -1} if
+     * it cannot be mapped to CC's charset.
+     */
+    public static int unicodeToTerminal(int chr) {
+        // ASCII and latin1 map to themselves
+        if (chr == 0 || chr == '\t' || chr == '\n' || chr == '\r' || (chr >= ' ' && chr <= '~') || (chr >= 160 && chr <= 255)) {
+            return chr;
         }
 
-        return builder.toString();
+        // Teletext block mosaics are *fairly* contiguous.
+        if (chr >= 0x1FB00 && chr <= 0x1FB13) return chr + (129 - 0x1fb00);
+        if (chr >= 0x1FB14 && chr <= 0x1FB1D) return chr + (150 - 0x1fb14);
+
+        // Everything else is just a manual lookup. For now, we just use a big switch statement, which we spin into a
+        // separate function to hopefully avoid inlining it here.
+        return unicodeToCraftOsFallback(chr);
     }
 
-    public static String normaliseLabel(String text) {
-        return removeSpecialCharacters(text, Math.min(32, text.length()));
+    private static int unicodeToCraftOsFallback(int c) {
+        return switch (c) {
+            case 0x263A -> 1;
+            case 0x263B -> 2;
+            case 0x2665 -> 3;
+            case 0x2666 -> 4;
+            case 0x2663 -> 5;
+            case 0x2660 -> 6;
+            case 0x2022 -> 7;
+            case 0x25D8 -> 8;
+            case 0x2642 -> 11;
+            case 0x2640 -> 12;
+            case 0x266A -> 14;
+            case 0x266B -> 15;
+            case 0x25BA -> 16;
+            case 0x25C4 -> 17;
+            case 0x2195 -> 18;
+            case 0x203C -> 19;
+            case 0x25AC -> 22;
+            case 0x21A8 -> 23;
+            case 0x2191 -> 24;
+            case 0x2193 -> 25;
+            case 0x2192 -> 26;
+            case 0x2190 -> 27;
+            case 0x221F -> 28;
+            case 0x2194 -> 29;
+            case 0x25B2 -> 30;
+            case 0x25BC -> 31;
+            case 0x1FB99 -> 127;
+            case 0x258C -> 149;
+            default -> -1;
+        };
     }
 
     /**
-     * Normalise a string from the clipboard, suitable for pasting into a computer.
+     * Check if a character is capable of being input and passed to a {@linkplain ComputerEvents#charTyped(ComputerEvents.Receiver, byte)
+     * "char" event}.
+     *
+     * @param chr The character to check.
+     * @return Whether this character can be typed.
+     */
+    public static boolean isTypableChar(int chr) {
+        return chr >= 0 && chr <= 255 && chr != 0 && chr != '\r' && chr != '\n';
+    }
+
+    private static boolean isAllowedInLabel(char c) {
+        // Limit to ASCII and latin1, excluding '§' (Minecraft's formatting character).
+        return (c >= ' ' && c <= '~') || (c >= 161 && c <= 255 && c != 167);
+    }
+
+    public static String normaliseLabel(String text) {
+        var length = Math.min(32, text.length());
+        var builder = new StringBuilder(length);
+        for (var i = 0; i < length; i++) {
+            var c = text.charAt(i);
+            builder.append(isAllowedInLabel(c) ? c : '?');
+        }
+        return builder.toString();
+    }
+
+    /**
+     * Convert a Java string to a Lua one (using the terminal charset), suitable for pasting into a computer.
      * <p>
      * This removes special characters and strips to the first line of text.
      *
      * @param clipboard The text from the clipboard.
-     * @return The normalised clipboard text.
+     * @return The encoded clipboard text.
      */
-    public static String normaliseClipboardString(String clipboard) {
-        // Clip to the first occurrence of \r or \n
-        var newLineIndex1 = clipboard.indexOf('\r');
-        var newLineIndex2 = clipboard.indexOf('\n');
+    public static ByteBuffer getClipboardString(String clipboard) {
+        var output = new byte[Math.min(MAX_PASTE_LENGTH, clipboard.length())];
+        var idx = 0;
 
-        int length;
-        if (newLineIndex1 >= 0 && newLineIndex2 >= 0) {
-            length = Math.min(newLineIndex1, newLineIndex2);
-        } else if (newLineIndex1 >= 0) {
-            length = newLineIndex1;
-        } else if (newLineIndex2 >= 0) {
-            length = newLineIndex2;
-        } else {
-            length = clipboard.length();
+        var iterator = clipboard.codePoints().iterator();
+        while (iterator.hasNext() && idx <= output.length) {
+            var chr = unicodeToTerminal(iterator.next());
+            if (chr < 0) continue; // Strip out unconvertible characters
+            if (!isTypableChar(chr)) break; // Stop at untypable ones.
+            output[idx++] = (byte) chr;
         }
 
-        return removeSpecialCharacters(clipboard, Math.min(length, 512));
+        return ByteBuffer.wrap(output, 0, idx).asReadOnlyBuffer();
     }
 }

projects/core/src/main/resources/data/computercraft/lua/rom/apis/paintutils.lua

@@ -47,12 +47,22 @@ local function sortCoords(startX, startY, endX, endY)
     return minX, maxX, minY, maxY
 end
 
---- Parses an image from a multi-line string
---
--- @tparam string image The string containing the raw-image data.
--- @treturn table The parsed image data, suitable for use with
--- [`paintutils.drawImage`].
--- @since 1.80pr1
+--[=[- Parses an image from a multi-line string
+
+@tparam string image The string containing the raw-image data.
+@treturn table The parsed image data, suitable for use with [`paintutils.drawImage`].
+@usage Parse an image from a string, and draw it.
+
+    local image = paintutils.parseImage([[
+     e  e
+
+    e    e
+     eeee
+    ]])
+    paintutils.drawImage(image, term.getCursorPos())
+
+@since 1.80pr1
+]=]
 function parseImage(image)
     expect(1, image, "string")
     local tImage = {}

projects/core/src/main/resources/data/computercraft/lua/rom/apis/parallel.lua

@@ -39,60 +39,55 @@ the other.
 @since 1.2
 ]]
 
+local exception = dofile("rom/modules/main/cc/internal/tiny_require.lua")("cc.internal.exception")
+
 local function create(...)
-    local tFns = table.pack(...)
-    local tCos = {}
-    for i = 1, tFns.n, 1 do
-        local fn = tFns[i]
+    local barrier_ctx = { co = coroutine.running() }
+
+    local functions = table.pack(...)
+    local threads = {}
+    for i = 1, functions.n, 1 do
+        local fn = functions[i]
         if type(fn) ~= "function" then
             error("bad argument #" .. i .. " (function expected, got " .. type(fn) .. ")", 3)
         end
 
-        tCos[i] = coroutine.create(fn)
+        threads[i] = { co = coroutine.create(function() return exception.try_barrier(barrier_ctx, fn) end), filter = nil }
     end
 
-    return tCos
+    return threads
 end
 
-local function runUntilLimit(_routines, _limit)
-    local count = #_routines
+local function runUntilLimit(threads, limit)
+    local count = #threads
     if count < 1 then return 0 end
     local living = count
 
-    local tFilters = {}
-    local eventData = { n = 0 }
+    local event = { n = 0 }
     while true do
-        for n = 1, count do
-            local r = _routines[n]
-            if r then
-                if tFilters[r] == nil or tFilters[r] == eventData[1] or eventData[1] == "terminate" then
-                    local ok, param = coroutine.resume(r, table.unpack(eventData, 1, eventData.n))
-                    if not ok then
-                        error(param, 0)
-                    else
-                        tFilters[r] = param
-                    end
-                    if coroutine.status(r) == "dead" then
-                        _routines[n] = nil
-                        living = living - 1
-                        if living <= _limit then
-                            return n
-                        end
+        for i = 1, count do
+            local thread = threads[i]
+            if thread and (thread.filter == nil or thread.filter == event[1] or event[1] == "terminate") then
+                local ok, param = coroutine.resume(thread.co, table.unpack(event, 1, event.n))
+                if ok then
+                    thread.filter = param
+                elseif type(param) == "string" and exception.can_wrap_errors() then
+                    error(exception.make_exception(param, thread.co))
+                else
+                    error(param, 0)
+                end
+
+                if coroutine.status(thread.co) == "dead" then
+                    threads[i] = false
+                    living = living - 1
+                    if living <= limit then
+                        return i
                     end
                 end
             end
         end
-        for n = 1, count do
-            local r = _routines[n]
-            if r and coroutine.status(r) == "dead" then
-                _routines[n] = nil
-                living = living - 1
-                if living <= _limit then
-                    return n
-                end
-            end
-        end
-        eventData = table.pack(os.pullEventRaw())
+
+        event = table.pack(os.pullEventRaw())
     end
 end
 
@@ -120,8 +115,8 @@ from the [`parallel.waitForAny`] call.
     print("Everything done!")
 ]]
 function waitForAny(...)
-    local routines = create(...)
-    return runUntilLimit(routines, #routines - 1)
+    local threads = create(...)
+    return runUntilLimit(threads, #threads - 1)
 end
 
 --[[- Switches between execution of the functions, until all of them are
@@ -144,6 +139,6 @@ from the [`parallel.waitForAll`] call.
     print("Everything done!")
 ]]
 function waitForAll(...)
-    local routines = create(...)
-    return runUntilLimit(routines, 0)
+    local threads = create(...)
+    return runUntilLimit(threads, 0)
 end

projects/core/src/main/resources/data/computercraft/lua/rom/apis/textutils.lua

@@ -7,9 +7,7 @@
 -- @module textutils
 -- @since 1.2
 
-local pgk_env = setmetatable({}, { __index = _ENV })
-pgk_env.require = dofile("rom/modules/main/cc/require.lua").make(pgk_env, "rom/modules/main")
-local require = pgk_env.require
+local require = dofile("rom/modules/main/cc/internal/tiny_require.lua")
 
 local expect = require("cc.expect")
 local expect, field = expect.expect, expect.field

projects/core/src/main/resources/data/computercraft/lua/rom/help/changelog.md

@@ -1,3 +1,22 @@
+# New features in CC: Tweaked 1.115.0
+
+* Support placing pocket computers on lecterns.
+* Suggest alternative table keys on `nil` errors.
+* Errors from inside `parallel` functions now have source information attached.
+* Expose printout contents to the Java API.
+
+Several bug fixes:
+* Ignore unrepresentable characters in `char`/`paste` events.
+
+# New features in CC: Tweaked 1.114.4
+
+* Allow typing/pasting any character in the CC charset.
+
+Several bug fixes:
+* Fix command computers being exposed as peripherals (Forge only).
+* Fix command computers having NBT set when placed in a Create contraption.
+* Use correct bounding box when checking for entities in turtle movement.
+
 # New features in CC: Tweaked 1.114.3
 
 * `wget` now prints the error that occurred, rather than a generic "Failed" (tizu69).

projects/core/src/main/resources/data/computercraft/lua/rom/help/whatsnew.md

@@ -1,10 +1,11 @@
-New features in CC: Tweaked 1.114.3
+New features in CC: Tweaked 1.115.0
 
-* `wget` now prints the error that occurred, rather than a generic "Failed" (tizu69).
-* Update several translations.
+* Support placing pocket computers on lecterns.
+* Suggest alternative table keys on `nil` errors.
+* Errors from inside `parallel` functions now have source information attached.
+* Expose printout contents to the Java API.
 
 Several bug fixes:
-* Fix `fs.isDriveRoot` returning true for non-existent files.
-* Fix possible memory leak when sending terminal contents.
+* Ignore unrepresentable characters in `char`/`paste` events.
 
 Type "help changelog" to see the full version history.

projects/core/src/main/resources/data/computercraft/lua/rom/modules/main/cc/internal/error_hints.lua

@@ -0,0 +1,167 @@
+-- SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+--
+-- SPDX-License-Identifier: MPL-2.0
+
+--[[- Internal tools for diagnosing errors and suggesting fixes.
+
+> [!DANGER]
+> This is an internal module and SHOULD NOT be used in your own code. It may
+> be removed or changed at any time.
+
+@local
+]]
+
+local debug, type, rawget = debug, type, rawget
+local sub, lower, find, min, abs = string.sub, string.lower, string.find, math.min, math.abs
+
+--[[- Compute the Optimal String Distance between two strings.
+
+@tparam string str_a The first string.
+@tparam string str_b The second string.
+@treturn number|nil The distance between two strings, or nil if they are two far
+apart.
+]]
+local function osa_distance(str_a, str_b, threshold)
+    local len_a, len_b = #str_a, #str_b
+
+    -- If the two strings are too different in length, then bail now.
+    if abs(len_a - len_b) > threshold then return end
+
+    -- Zero-initialise our distance table.
+    local d = {}
+    for i = 1, (len_a + 1) * (len_b + 1) do d[i] = 0 end
+
+    -- Then fill the first row and column
+    local function idx(a, b) return a * (len_a + 1) + b + 1 end
+    for i = 0, len_a do d[idx(i, 0)] = i end
+    for j = 0, len_b do d[idx(0, j)] = j end
+
+    -- Then compute our distance
+    for i = 1, len_a do
+        local char_a = sub(str_a, i, i)
+        for j = 1, len_b do
+            local char_b = sub(str_b, j, j)
+
+            local sub_cost
+            if char_a == char_b then
+                sub_cost = 0
+            elseif lower(char_a) == lower(char_b) then
+                sub_cost = 0.5
+            else
+                sub_cost = 1
+            end
+
+            local new_cost = min(
+                d[idx(i - 1, j)] + 1, -- Deletion
+                d[idx(i, j - 1)] + 1, -- Insertion,
+                d[idx(i - 1, j - 1)] + sub_cost -- Substitution
+            )
+
+            -- Transposition
+            if i > 1 and j > 1 and char_a == sub(str_b, j - 1, j - 1) and char_b == sub(str_a, i - 1, i - 1) then
+                local trans_cost = d[idx(i - 2, j - 2)] + 1
+                if trans_cost < new_cost then new_cost = trans_cost end
+            end
+
+            d[idx(i, j)] = new_cost
+        end
+    end
+
+    local result = d[idx(len_a, len_b)]
+    if result <= threshold then return result else return nil end
+end
+
+--- Check whether this suggestion is useful.
+local function useful_suggestion(str)
+    local len = #str
+    return len > 0 and len < 32 and find(str, "^[%a_]%w*$")
+end
+
+local function get_suggestions(is_global, value, key, thread, frame_offset)
+    if not useful_suggestion(key) then return end
+
+    -- Pick a maximum number of edits. We're more lenient on longer strings, but
+    -- still only allow two mistakes.
+    local threshold = #key >= 5 and 2 or 1
+
+    -- Find all items in the table, and see if they seem similar.
+    local suggestions = {}
+    local function process_suggestion(k)
+        if type(k) ~= "string" or not useful_suggestion(k) then return end
+
+        local distance = osa_distance(k, key, threshold)
+        if distance then
+            if distance < threshold then
+                -- If this is better than any existing match, then prefer it.
+                suggestions = { k }
+                threshold = distance
+            else
+                -- Otherwise distance==threshold, and so just add it.
+                suggestions[#suggestions + 1] = k
+            end
+        end
+    end
+
+    while type(value) == "table" do
+        for k in next, value do process_suggestion(k) end
+
+        local mt = debug.getmetatable(value)
+        if mt == nil then break end
+        value = rawget(mt, "__index")
+    end
+
+    -- If we're attempting to lookup a global, then also suggest any locals and
+    -- upvalues. Our upvalues will be incomplete, but maybe a little useful?
+    if is_global then
+        for i = 1, 200 do
+            local name = debug.getlocal(thread, frame_offset, i)
+            if not name then break end
+            process_suggestion(name)
+        end
+
+        local func = debug.getinfo(thread, frame_offset, "f").func
+        for i = 1, 255 do
+            local name = debug.getupvalue(func, i)
+            if not name then break end
+            process_suggestion(name)
+        end
+    end
+
+    table.sort(suggestions)
+
+    return suggestions
+end
+
+--[[- Get a tip to display at the end of an error.
+
+@tparam string err The error message.
+@tparam coroutine thread The current thread.
+@tparam number frame_offset The offset into the thread where the current frame exists
+@return An optional message to append to the error.
+]]
+local function get_tip(err, thread, frame_offset)
+    local nil_op = err:match("^attempt to (%l+) .* %(a nil value%)")
+    if not nil_op then return end
+
+    local has_error_info, error_info = pcall(require, "cc.internal.error_info")
+    if not has_error_info then return end
+    local op, is_global, table, key = error_info.info_for_nil(thread, frame_offset)
+    if op == nil or op ~= nil_op then return end
+
+    local suggestions = get_suggestions(is_global, table, key, thread, frame_offset)
+    if not suggestions or next(suggestions) == nil then return end
+
+    local pretty = require "cc.pretty"
+    local msg = "Did you mean: "
+
+    local n_suggestions = min(3, #suggestions)
+    for i = 1, n_suggestions do
+        if i > 1 then
+            if i == n_suggestions then msg = msg .. " or " else msg = msg .. ", " end
+        end
+        msg = msg .. pretty.text(suggestions[i], colours.lightGrey)
+    end
+    return msg .. "?"
+end
+
+return { get_tip = get_tip }

projects/core/src/main/resources/data/computercraft/lua/rom/modules/main/cc/internal/exception.lua

@@ -12,7 +12,7 @@
 ]]
 
 local expect = require "cc.expect".expect
-local error_printer = require "cc.internal.error_printer"
+local type, debug, coroutine = type, debug, coroutine
 
 local function find_frame(thread, file, line)
     -- Scan the first 16 frames for something interesting.
@@ -21,14 +21,14 @@ local function find_frame(thread, file, line)
         if not frame then break end
 
         if frame.short_src == file and frame.what ~= "C" and frame.currentline == line then
-            return frame
+            return offset, frame
         end
     end
 end
 
 --[[- Check whether this error is an exception.
 
-Currently we don't provide a stable API for throwing (and propogating) rich
+Currently we don't provide a stable API for throwing (and propagating) rich
 errors, like those supported by this module. In lieu of that, we describe the
 exception protocol, which may be used by user-written coroutine managers to
 throw exceptions which are pretty-printed by the shell:
@@ -64,6 +64,86 @@ local function is_exception(exn)
     return mt and mt.__name == "exception" and type(rawget(exn, "message")) == "string" and type(rawget(exn, "thread")) == "thread"
 end
 
+local exn_mt = {
+    __name = "exception",
+    __tostring = function(self) return self.message end,
+}
+
+--[[- Create a new exception from a message and thread.
+
+@tparam string message The exception message.
+@tparam coroutine thread The coroutine the error occurred on.
+@return The constructed exception.
+]]
+local function make_exception(message, thread)
+    return setmetatable({ message = message, thread = thread }, exn_mt)
+end
+
+--[[- A marker function for [`try`] and the wider exception machinery.
+
+This function is typically the first function on the call stack. It acts as both
+a signifier that this function is exception aware, and allows us to store
+additional information for the exception machinery on the call stack.
+
+@see can_wrap_errors
+]]
+local try_barrier = debug.getregistry().cc_try_barrier
+if not try_barrier then
+    -- We define an extra "bounce" function to prevent f(...) being treated as a
+    -- tail call, and so ensure the barrier remains on the stack.
+    local function bounce(...) return ... end
+
+    --- @tparam { co = coroutine, can_wrap ?= boolean } parent The parent coroutine.
+    -- @tparam function f The function to call.
+    -- @param ... The arguments to this function.
+    try_barrier = function(parent, f, ...) return bounce(f(...)) end
+
+    debug.getregistry().cc_try_barrier = try_barrier
+end
+
+-- Functions that act as a barrier for exceptions.
+local pcall_functions = { [pcall] = true, [xpcall] = true, [load] = true }
+
+--[[- Check to see whether we can wrap errors into an exception.
+
+This scans the current thread (up to a limit), and any parent threads, to
+determine if there is a pcall anywhere on the callstack. If not, then we know
+the error message is not observed by user code, and so may be wrapped into an
+exception.
+
+@tparam[opt] coroutine The thread to check. Defaults to the current thread.
+@treturn boolean Whether we can wrap errors into exceptions.
+]]
+local function can_wrap_errors(thread)
+    if not thread then thread = coroutine.running() end
+
+    for offset = 0, 31 do
+        local frame = debug.getinfo(thread, offset, "f")
+        if not frame then return false end
+
+        local func = frame.func
+        if func == try_barrier then
+            -- If we've a try barrier, then extract the parent coroutine and
+            -- check if it can wrap errors.
+            local _, parent = debug.getlocal(thread, offset, 1)
+            if type(parent) ~= "table" or type(parent.co) ~= "thread" then return false end
+
+            local result = parent.can_wrap
+            if result == nil then
+                result = can_wrap_errors(parent.co)
+                parent.can_wrap = result
+            end
+
+            return result
+        elseif pcall_functions[func] then
+            -- If we're a pcall, then abort.
+            return false
+        end
+    end
+
+    return false
+end
+
 --[[- Attempt to call the provided function `func` with the provided arguments.
 
 @tparam function func The function to call.
@@ -79,8 +159,8 @@ end
 local function try(func, ...)
     expect(1, func, "function")
 
-    local co = coroutine.create(func)
-    local result = table.pack(coroutine.resume(co, ...))
+    local co = coroutine.create(try_barrier)
+    local result = table.pack(coroutine.resume(co, { co = co, can_wrap = true }, func, ...))
 
     while coroutine.status(co) ~= "dead" do
         local event = table.pack(os.pullEventRaw(result[2]))
@@ -111,11 +191,11 @@ local function report(err, thread, source_map)
 
     if type(err) ~= "string" then return end
 
-    local file, line = err:match("^([^:]+):(%d+):")
+    local file, line, err = err:match("^([^:]+):(%d+): (.*)")
     if not file then return end
     line = tonumber(line)
 
-    local frame = find_frame(thread, file, line)
+    local frame_offset, frame = find_frame(thread, file, line)
     if not frame or not frame.currentcolumn then return end
 
     local column = frame.currentcolumn
@@ -152,16 +232,22 @@ local function report(err, thread, source_map)
     -- Could not determine the line. Bail.
     if not line_contents or #line_contents == "" then return end
 
-    error_printer({
+    require("cc.internal.error_printer")({
         get_pos = function() return line, column end,
         get_line = function() return line_contents end,
     }, {
         { tag = "annotate", start_pos = column, end_pos = column, msg = "" },
+        require "cc.internal.error_hints".get_tip(err, thread, frame_offset),
     })
 end
 
 
 return {
+    make_exception = make_exception,
+
+    try_barrier = try_barrier,
+    can_wrap_errors = can_wrap_errors,
+
     try = try,
     report = report,
 }

projects/core/src/main/resources/data/computercraft/lua/rom/modules/main/cc/internal/tiny_require.lua

@@ -0,0 +1,37 @@
+-- SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+--
+-- SPDX-License-Identifier: MPL-2.0
+
+--[[- A minimal implementation of require.
+
+This is intended for use with APIs, and other internal code which is not run in
+the [`shell`] environment. This allows us to avoid some of the overhead of
+loading the full [`cc.require`] module.
+
+> [!DANGER]
+> This is an internal module and SHOULD NOT be used in your own code. It may
+> be removed or changed at any time.
+
+@local
+
+@tparam string name The module to require.
+@return The required module.
+]]
+
+local loaded = {}
+local env = setmetatable({}, { __index = _G })
+local function require(name)
+    local result = loaded[name]
+    if result then return result end
+
+    local path = "rom/modules/main/" .. name:gsub("%.", "/")
+    if fs.exists(path .. ".lua") then
+        result = assert(loadfile(path .. ".lua", nil, env))()
+    else
+        result = assert(loadfile(path .. "/init.lua", nil, env))()
+    end
+    loaded[name] = result
+    return result
+end
+env.require = require
+return require

projects/core/src/main/resources/data/computercraft/lua/rom/programs/lua.lua

@@ -31,7 +31,7 @@ setmetatable(tEnv, { __index = _ENV })
 do
     local make_package = require "cc.require".make
     local dir = shell.dir()
-    _ENV.require, _ENV.package = make_package(_ENV, dir)
+    tEnv.require, tEnv.package = make_package(tEnv, dir)
 end
 
 if term.isColour() then

projects/core/src/test/java/dan200/computercraft/core/ComputerTestDelegate.java

@@ -413,7 +413,7 @@ public class ComputerTestDelegate {
             var wholeMessage = new StringBuilder();
             if (message != null) wholeMessage.append(message);
             if (trace != null) {
-                if (wholeMessage.length() != 0) wholeMessage.append('\n');
+                if (!wholeMessage.isEmpty()) wholeMessage.append('\n');
                 wholeMessage.append(trace);
             }
 

projects/core/src/test/java/dan200/computercraft/core/lua/errorinfo/ErrorInfoLibTest.java

@@ -0,0 +1,76 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.core.lua.errorinfo;
+
+import org.intellij.lang.annotations.Language;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.squiddev.cobalt.*;
+import org.squiddev.cobalt.compiler.CompileException;
+import org.squiddev.cobalt.compiler.LoadState;
+import org.squiddev.cobalt.lib.CoreLibraries;
+
+import java.io.ByteArrayInputStream;
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class ErrorInfoLibTest {
+    @Test
+    public void testNilInfoForUnknownLibFunction() throws LuaError, CompileException {
+        var state = newState();
+        var thread = captureError(state, "string.forma()");
+
+        assertEquals(
+            new ErrorInfoLib.NilInfo(
+                "call",
+                new ErrorInfoLib.ValueSource(false, state.globals().rawget("string"), ValueFactory.valueOf("forma"))
+            ),
+            ErrorInfoLib.getInfoForNil(state, thread, 0)
+        );
+    }
+
+    @Test
+    public void testNilInfoForUnknownGlobal() throws LuaError, CompileException {
+        var state = newState();
+        var thread = captureError(state, "pront()");
+
+        assertEquals(
+            new ErrorInfoLib.NilInfo(
+                "call",
+                new ErrorInfoLib.ValueSource(true, state.globals(), ValueFactory.valueOf("pront"))
+            ),
+            ErrorInfoLib.getInfoForNil(state, thread, 0)
+        );
+    }
+
+    @Test
+    public void testNilInfoForComplexExpression() throws LuaError, CompileException {
+        var state = newState();
+        var thread = captureError(state, "x = { { y = 1 } }; for i = 1, #x do x[i].z() end");
+
+        var inner = ((LuaTable) state.globals().rawget("x")).rawget(1);
+        assertEquals(
+            new ErrorInfoLib.NilInfo(
+                "call",
+                new ErrorInfoLib.ValueSource(false, inner, ValueFactory.valueOf("z"))
+            ),
+            ErrorInfoLib.getInfoForNil(state, thread, 0)
+        );
+    }
+
+    private static LuaState newState() throws LuaError {
+        var state = new LuaState();
+        CoreLibraries.standardGlobals(state);
+        return state;
+    }
+
+    private static LuaThread captureError(LuaState state, @Language("lua") String contents) throws CompileException, LuaError {
+        var fn = LoadState.load(state, new ByteArrayInputStream(contents.getBytes(StandardCharsets.UTF_8)), "=in.lua", state.globals());
+        var thread = new LuaThread(state, fn);
+        Assertions.assertThrows(LuaError.class, () -> LuaThread.run(thread, Constants.NIL));
+        return thread;
+    }
+}