Bump CC:T to 1.108.4

This tries to cover some holes in our existing coverage.

 - Port some of our Java readable handle tests to Lua (and also clean up
   the Java versions to stop using ObjectWrapper - that dates to
   pre-@LuaFunction!)

 - Test a couple of discrepancies between binary and text handles. This
   is mostly to do with the original number-based .read() and .write()
   interface for binary handles.

 - Fix a couple of edge cases in file-size accounting.

.pre-commit-config.yaml

@@ -44,7 +44,7 @@ repos:
     name: Check Java codestyle
     files: ".*\\.java$"
     language: system
-    entry: ./gradlew checkstyleMain checkstyleTest
+    entry: ./gradlew checkstyle
     pass_filenames: false
     require_serial: true
   - id: illuaminate

.reuse/dep5

@@ -10,8 +10,8 @@ Files:
   projects/common/src/testMod/resources/data/cctest/structures/*
   projects/fabric/src/generated/*
   projects/forge/src/generated/*
-  projects/web/src/export/index.json
-  projects/web/src/export/items/minecraft/*
+  projects/web/src/htmlTransform/export/index.json
+  projects/web/src/htmlTransform/export/items/minecraft/*
 Comment: Generated/data files are CC0.
 Copyright: The CC: Tweaked Developers
 License: CC0-1.0
@@ -37,10 +37,10 @@ Files:
   projects/fabric/src/testMod/resources/computercraft-gametest.fabric.mixins.json
   projects/fabric/src/testMod/resources/fabric.mod.json
   projects/forge/src/client/resources/computercraft-client.forge.mixins.json
-  projects/web/src/mount/.settings
-  projects/web/src/mount/example.nfp
-  projects/web/src/mount/example.nft
-  projects/web/src/mount/expr_template.lua
+  projects/web/src/frontend/mount/.settings
+  projects/web/src/frontend/mount/example.nfp
+  projects/web/src/frontend/mount/example.nft
+  projects/web/src/frontend/mount/expr_template.lua
   projects/web/tsconfig.json
 Comment: Several assets where it's inconvenient to create a .license file.
 Copyright: The CC: Tweaked Developers
@@ -53,19 +53,32 @@ Files:
   projects/common/src/main/resources/assets/computercraft/textures/*
   projects/common/src/main/resources/pack.mcmeta
   projects/common/src/main/resources/pack.png
+  projects/core/src/main/resources/assets/computercraft/textures/gui/term_font.png
   projects/core/src/main/resources/data/computercraft/lua/rom/autorun/.ignoreme
   projects/core/src/main/resources/data/computercraft/lua/rom/help/*
   projects/core/src/main/resources/data/computercraft/lua/rom/programs/fun/advanced/levels/*
-  projects/web/src/export/items/computercraft/*
+  projects/web/src/htmlTransform/export/items/computercraft/*
 Comment: Bulk-license original assets as CCPL.
 Copyright: 2011 Daniel Ratcliffe
 License: LicenseRef-CCPL
 
+Files:
+  projects/common/src/main/resources/assets/computercraft/lang/cs_cz.json
+  projects/common/src/main/resources/assets/computercraft/lang/ko_kr.json
+  projects/common/src/main/resources/assets/computercraft/lang/pl_pl.json
+  projects/common/src/main/resources/assets/computercraft/lang/pt_br.json
+  projects/common/src/main/resources/assets/computercraft/lang/ru_ru.json
+  projects/common/src/main/resources/assets/computercraft/lang/uk_ua.json
+  projects/common/src/main/resources/assets/computercraft/lang/zh_cn.json
+Comment: Community-contributed license files
+Copyright: 2017 The CC: Tweaked Developers
+License: LicenseRef-CCPL
+
 Files:
   projects/common/src/main/resources/assets/computercraft/lang/*
 Comment: Community-contributed license files
 Copyright: 2017 The CC: Tweaked Developers
-License: LicenseRef-CCPL
+License: MPL-2.0
 
 Files:
   .github/*

CONTRIBUTING.md

@@ -100,7 +100,6 @@ about how you can build on that until you've covered everything!
 [new-issue]: https://github.com/cc-tweaked/CC-Tweaked/issues/new/choose "Create a new issue"
 [community]: README.md#community "Get in touch with the community."
 [Adoptium]: https://adoptium.net/temurin/releases?version=17 "Download OpenJDK 17"
-[checkstyle]: https://checkstyle.org/
 [illuaminate]: https://github.com/SquidDev/illuaminate/ "Illuaminate on GitHub"
 [weblate]: https://i18n.tweaked.cc/projects/cc-tweaked/minecraft/ "CC: Tweaked weblate instance"
 [docs]: https://tweaked.cc/ "CC: Tweaked documentation"

build.gradle.kts

@@ -2,7 +2,11 @@
 //
 // SPDX-License-Identifier: MPL-2.0
 
+import cc.tweaked.gradle.JUnitExt
+import net.fabricmc.loom.api.LoomGradleExtensionAPI
+import net.fabricmc.loom.util.gradle.SourceSetHelper
 import org.jetbrains.gradle.ext.compiler
+import org.jetbrains.gradle.ext.runConfigurations
 import org.jetbrains.gradle.ext.settings
 
 plugins {
@@ -38,6 +42,50 @@ githubRelease {
 
 tasks.publish { dependsOn(tasks.githubRelease) }
 
+idea.project.settings.runConfigurations {
+    register<JUnitExt>("Core Tests") {
+        vmParameters = "-ea"
+        moduleName = "${idea.project.name}.core.test"
+        packageName = ""
+    }
+
+    register<JUnitExt>("CraftOS Tests") {
+        vmParameters = "-ea"
+        moduleName = "${idea.project.name}.core.test"
+        className = "dan200.computercraft.core.ComputerTestDelegate"
+    }
+
+    register<JUnitExt>("CraftOS Tests (Fast)") {
+        vmParameters = "-ea -Dcc.skip_keywords=slow"
+        moduleName = "${idea.project.name}.core.test"
+        className = "dan200.computercraft.core.ComputerTestDelegate"
+    }
+
+    register<JUnitExt>("Common Tests") {
+        vmParameters = "-ea"
+        moduleName = "${idea.project.name}.common.test"
+        packageName = ""
+    }
+
+    register<JUnitExt>("Fabric Tests") {
+        val fabricProject = evaluationDependsOn(":fabric")
+        val classPathGroup = fabricProject.extensions.getByType<LoomGradleExtensionAPI>().mods
+            .joinToString(File.pathSeparator + File.pathSeparator) { modSettings ->
+                SourceSetHelper.getClasspath(modSettings, project).joinToString(File.pathSeparator) { it.absolutePath }
+            }
+
+        vmParameters = "-ea -Dfabric.classPathGroups=$classPathGroup"
+        moduleName = "${idea.project.name}.fabric.test"
+        packageName = ""
+    }
+
+    register<JUnitExt>("Forge Tests") {
+        vmParameters = "-ea"
+        moduleName = "${idea.project.name}.forge.test"
+        packageName = ""
+    }
+}
+
 idea.project.settings.compiler.javac {
     // We want ErrorProne to be present when compiling via IntelliJ, as it offers some helpful warnings
     // and errors. Loop through our source sets and find the appropriate flags.

buildSrc/build.gradle.kts

@@ -50,10 +50,11 @@ dependencies {
     implementation(libs.curseForgeGradle)
     implementation(libs.fabric.loom)
     implementation(libs.forgeGradle)
+    implementation(libs.ideaExt)
     implementation(libs.librarian)
     implementation(libs.minotaur)
-    implementation(libs.quiltflower)
     implementation(libs.vanillaGradle)
+    implementation(libs.vineflower)
 }
 
 gradlePlugin {

buildSrc/src/main/kotlin/cc-tweaked.fabric.gradle.kts

@@ -12,7 +12,7 @@ import cc.tweaked.gradle.MinecraftConfigurations
 plugins {
     `java-library`
     id("fabric-loom")
-    id("io.github.juuxel.loom-quiltflower")
+    id("io.github.juuxel.loom-vineflower")
     id("cc-tweaked.java-convention")
 }
 

buildSrc/src/main/kotlin/cc-tweaked.java-convention.gradle.kts

@@ -66,6 +66,7 @@ repositories {
             includeGroup("me.shedaniel.cloth")
             includeGroup("me.shedaniel")
             includeGroup("mezz.jei")
+            includeGroup("org.teavm")
             includeModule("com.terraformersmc", "modmenu")
             includeModule("me.lucko", "fabric-permissions-api")
         }
@@ -99,7 +100,10 @@ sourceSets.all {
             check("FutureReturnValueIgnored", CheckSeverity.OFF) // Too many false positives with Netty
 
             check("NullAway", CheckSeverity.ERROR)
-            option("NullAway:AnnotatedPackages", listOf("dan200.computercraft", "net.fabricmc.fabric.api").joinToString(","))
+            option(
+                "NullAway:AnnotatedPackages",
+                listOf("dan200.computercraft", "cc.tweaked", "net.fabricmc.fabric.api").joinToString(","),
+            )
             option("NullAway:ExcludedFieldAnnotations", listOf("org.spongepowered.asm.mixin.Shadow").joinToString(","))
             option("NullAway:CastToNonNullMethod", "dan200.computercraft.core.util.Nullability.assertNonNull")
             option("NullAway:CheckOptionalEmptiness")
@@ -174,6 +178,12 @@ project.plugins.withType(CCTweakedPlugin::class.java) {
     }
 }
 
+tasks.register("checkstyle") {
+    description = "Run Checkstyle on all sources"
+    group = LifecycleBasePlugin.VERIFICATION_GROUP
+    dependsOn(tasks.withType(Checkstyle::class.java))
+}
+
 spotless {
     encoding = StandardCharsets.UTF_8
     lineEndings = LineEnding.UNIX
@@ -191,6 +201,7 @@ spotless {
 
     val ktlintConfig = mapOf(
         "ktlint_standard_no-wildcard-imports" to "disabled",
+        "ktlint_standard_class-naming" to "disabled",
         "ij_kotlin_allow_trailing_comma" to "true",
         "ij_kotlin_allow_trailing_comma_on_call_site" to "true",
     )

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

@@ -173,7 +173,7 @@ abstract class CCTweakedExtension(
     }
 
     fun <T> jacoco(task: NamedDomainObjectProvider<T>) where T : Task, T : JavaForkOptions {
-        val classDump = project.buildDir.resolve("jacocoClassDump/${task.name}")
+        val classDump = project.layout.buildDirectory.dir("jacocoClassDump/${task.name}")
         val reportTaskName = "jacoco${task.name.capitalized()}Report"
 
         val jacoco = project.extensions.getByType(JacocoPluginExtension::class.java)
@@ -185,7 +185,7 @@ abstract class CCTweakedExtension(
             jacoco.applyTo(this)
             extensions.configure(JacocoTaskExtension::class.java) {
                 includes = listOf("dan200.computercraft.*")
-                classDumpDir = classDump
+                classDumpDir = classDump.get().asFile
 
                 // Older versions of modlauncher don't include a protection domain (and thus no code
                 // source). Jacoco skips such classes by default, so we need to explicitly include them.

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

@@ -9,6 +9,10 @@ import org.gradle.api.Project
 import org.gradle.api.plugins.JavaPlugin
 import org.gradle.api.plugins.JavaPluginExtension
 import org.gradle.jvm.toolchain.JavaLanguageVersion
+import org.gradle.plugins.ide.idea.model.IdeaModel
+import org.jetbrains.gradle.ext.IdeaExtPlugin
+import org.jetbrains.gradle.ext.runConfigurations
+import org.jetbrains.gradle.ext.settings
 
 /**
  * Configures projects to match a shared configuration.
@@ -21,6 +25,20 @@ class CCTweakedPlugin : Plugin<Project> {
             val sourceSets = project.extensions.getByType(JavaPluginExtension::class.java).sourceSets
             cct.sourceDirectories.add(SourceSetReference.internal(sourceSets.getByName("main")))
         }
+
+        project.plugins.withType(IdeaExtPlugin::class.java) { extendIdea(project) }
+    }
+
+    /**
+     * Extend the [IdeaExtPlugin] plugin's `runConfiguration` container to also support [JUnitExt].
+     */
+    private fun extendIdea(project: Project) {
+        val ideaModel = project.extensions.findByName("idea") as IdeaModel? ?: return
+        val ideaProject = ideaModel.project ?: return
+
+        ideaProject.settings.runConfigurations {
+            registerFactory(JUnitExt::class.java) { name -> project.objects.newInstance(JUnitExt::class.java, name) }
+        }
     }
 
     companion object {

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

@@ -4,6 +4,7 @@
 
 package cc.tweaked.gradle
 
+import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.tasks.AbstractExecTask
 import org.gradle.api.tasks.OutputDirectory
@@ -11,5 +12,5 @@ import java.io.File
 
 abstract class ExecToDir : AbstractExecTask<ExecToDir>(ExecToDir::class.java) {
     @get:OutputDirectory
-    abstract val output: Property<File>
+    abstract val output: DirectoryProperty
 }

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

@@ -5,6 +5,8 @@
 package cc.tweaked.gradle
 
 import org.gradle.api.artifacts.dsl.DependencyHandler
+import org.gradle.api.file.FileSystemLocation
+import org.gradle.api.file.FileSystemLocationProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.JavaExec
@@ -124,3 +126,6 @@ class CloseScope : AutoCloseable {
 
 /** Proxy method to avoid overload ambiguity. */
 fun <T> Property<T>.setProvider(provider: Provider<out T>) = set(provider)
+
+/** Short-cut method to get the absolute path of a [FileSystemLocation] provider. */
+fun Provider<out FileSystemLocation>.getAbsolutePath(): String = get().asFile.absolutePath

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

@@ -0,0 +1,23 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package cc.tweaked.gradle
+
+import org.jetbrains.gradle.ext.JUnit
+import javax.inject.Inject
+
+/**
+ * A version of [JUnit] with a functional [className].
+ *
+ * See [#92](https://github.com/JetBrains/gradle-idea-ext-plugin/issues/92).
+ */
+open class JUnitExt @Inject constructor(nameParam: String) : JUnit(nameParam) {
+    override fun toMap(): MutableMap<String, *> {
+        val map = HashMap(super.toMap())
+        // Should be "class" instead of "className".
+        // See https://github.com/JetBrains/intellij-community/blob/9ba394021dc73a3926f13d6d6cdf434f9ee7046d/plugins/junit/src/com/intellij/execution/junit/JUnitRunConfigurationImporter.kt#L39
+        map["class"] = className
+        return map
+    }
+}

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

@@ -58,7 +58,7 @@ abstract class ClientJavaExec : JavaExec() {
         if (!clientDebug) systemProperty("cctest.client", "")
         if (renderdoc) environment("LD_PRELOAD", "/usr/lib/librenderdoc.so")
         systemProperty("cctest.gametest-report", testResults.get().asFile.absoluteFile)
-        workingDir(project.buildDir.resolve("gametest").resolve(name))
+        workingDir(project.layout.buildDirectory.dir("gametest/$name"))
     }
 
     init {

config/checkstyle/checkstyle.xml

@@ -112,7 +112,9 @@ SPDX-License-Identifier: MPL-2.0
         <module name="LambdaParameterName" />
         <module name="LocalFinalVariableName" />
         <module name="LocalVariableName" />
-        <module name="MemberName" />
+        <module name="MemberName">
+            <property name="format" value="^\$?[a-z][a-zA-Z0-9]*$" />
+        </module>
         <module name="MethodName">
             <property name="format" value="^(computercraft\$)?[a-z][a-zA-Z0-9]*$" />
         </module>
@@ -122,7 +124,7 @@ SPDX-License-Identifier: MPL-2.0
         </module>
         <module name="ParameterName" />
         <module name="StaticVariableName">
-            <property name="format" value="^[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z_]+)?$" />
+            <property name="format" value="^[a-z][a-zA-Z0-9]*$" />
         </module>
         <module name="TypeName" />
 

config/checkstyle/suppressions.xml

@@ -16,4 +16,10 @@ SPDX-License-Identifier: MPL-2.0
 
     <!-- The commands API is documented in Lua. -->
     <suppress checks="SummaryJavadocCheck" files=".*[\\/]CommandAPI.java" />
+
+    <!-- Allow putting files in other packages if they look like our TeaVM stubs. -->
+    <suppress checks="PackageName" files=".*[\\/]T[A-Za-z]+.java" />
+
+    <!-- Allow underscores in our test classes. -->
+    <suppress checks="MethodName" files=".*Contract.java" />
 </suppressions>

doc/events/char.md

@@ -6,7 +6,7 @@ see: key To listen to any key press.
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 The [`char`] event is fired when a character is typed on the keyboard.

doc/events/file_transfer.md

@@ -29,7 +29,7 @@ for _, file in ipairs(files.getFiles()) do
   local size = file.seek("end")
   file.seek("set", 0)
 
-  print(file.getName() .. " " .. file.getSize())
+  print(file.getName() .. " " .. size)
 end
 ```
 

doc/events/key.md

@@ -5,7 +5,7 @@ module: [kind=event] key
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 This event is fired when any key is pressed while the terminal is focused.

doc/events/key_up.md

@@ -6,7 +6,7 @@ see: keys For a lookup table of the given keys.
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 Fired whenever a key is released (or the terminal is closed while a key was being pressed).

doc/events/mouse_click.md

@@ -5,7 +5,7 @@ module: [kind=event] mouse_click
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 This event is fired when the terminal is clicked with a mouse. This event is only fired on advanced computers (including

doc/events/mouse_drag.md

@@ -6,7 +6,7 @@ see: mouse_click For when a mouse button is initially pressed.
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 This event is fired every time the mouse is moved while a mouse button is being held.

doc/events/mouse_scroll.md

@@ -5,7 +5,7 @@ module: [kind=event] mouse_scroll
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 This event is fired when a mouse wheel is scrolled in the terminal.

doc/events/mouse_up.md

@@ -5,7 +5,7 @@ module: [kind=event] mouse_up
 <!--
 SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 
-SPDX-License-Identifier: LicenseRef-CCPL
+SPDX-License-Identifier: MPL-2.0
 -->
 
 This event is fired when a mouse button is released or a held mouse leaves the computer's terminal.

doc/reference/breaking_changes.md

@@ -0,0 +1,67 @@
+---
+module: [kind=reference] breaking_changes
+---
+
+<!--
+SPDX-FileCopyrightText: 2019 The CC: Tweaked Developers
+
+SPDX-License-Identifier: MPL-2.0
+-->
+
+# Incompatibilities between versions
+
+CC: Tweaked tries to remain as compatible between versions as possible, meaning most programs written for older version
+of the mod should run fine on later versions.
+
+> [External peripherals][!WARNING]
+>
+> While CC: Tweaked is relatively stable across versions, this may not be true for other mods which add their own
+> peripherals. Older programs which interact with external blocks may not work on newer versions of the game.
+
+However, some changes to the underlying game, or CC: Tweaked's own internals may break some programs. This page serves
+as documentation for breaking changes and "gotchas" one should look out for between versions.
+
+## Minecraft 1.13 {#mc-1.13}
+ - The "key code" for [`key`] and [`key_up`] events has changed, due to Minecraft updating to LWJGL 3. Make sure you're
+   using the constants provided by the [`keys`] API, rather than hard-coding numerical values.
+
+   Related to this change, the numpad enter key now has a different key code to the enter key. You may need to adjust
+   your programs to handle both. (Note, the `keys.numpadEnter` constant was defined in pre-1.13 versions of CC, but the
+   `keys.enter` constant was queued when the key was pressed)
+
+ - Minecraft 1.13 removed the concept of item damage and block metadata (see ["The Flattening"][flattening]). As a
+   result `turtle.inspect` no longer provides block metadata, and `turtle.getItemDetail` no longer provides damage.
+
+   - Block states (`turtle.inspect().state`) should provide all the same information as block metadata, but in a much
+     more understandable format.
+
+   - Item and block names now represent a unique item type. For instance, wool is split into 16 separate items
+     (`minecraft:white_wool`, etc...) rather than a single `minecraft:wool` with each meta/damage value specifying the
+     colour.
+
+ - Custom ROMs are now provided using data packs rather than resource packs. This should mostly be a matter of renaming
+   the "assets" folder to "data", and placing it in "datapacks", but there are a couple of other gotchas to look out
+   for:
+
+   - Data packs [impose some restrictions on file names][legal_data_pack]. As a result, your programs and directories
+     must all be lower case.
+   - Due to how data packs are read by CC: Tweaked, you may need to use the `/reload` command to see changes to your
+     pack show up on the computer.
+
+   See [the example datapack][datapack-example] for how to get started.
+
+ - Turtles can now be waterlogged and move "through" water sources rather than breaking them.
+
+## CC: Tweaked 1.88.0 {#cc-1.88}
+ - Unlabelled computers and turtles now keep their ID when broken, meaning that unlabelled computers/items do not stack.
+
+## ComputerCraft 1.80pr1 {#cc-1.80}
+ - Programs run via `shell.run` are now started in their own isolated environment. This means globals set by programs
+   will not be accessible outside of this program.
+
+ - Programs containing `/` are looked up in the current directory and are no longer looked up on the path. For instance,
+   you can no longer type `turtle/excavate` to run `/rom/programs/turtle/excavate.lua`.
+
+[flattening]: https://minecraft.wiki.com/w/Java_Edition_1.13/Flattening
+[legal_data_pack]: https://minecraft.gamepedia.com/Tutorials/Creating_a_data_pack#Legal_characters
+[datapack-example]: https://github.com/cc-tweaked/datapack-example "An example datapack for CC: Tweaked"

gradle.properties

@@ -10,7 +10,7 @@ kotlin.jvm.target.validation.mode=error
 
 # Mod properties
 isUnstable=false
-modVersion=1.108.0
+modVersion=1.108.4
 
 # Minecraft properties: We want to configure this here so we can read it in settings.gradle
 mcVersion=1.20.1

gradle/libs.versions.toml

@@ -12,15 +12,16 @@ fabric-loader = "0.14.21"
 forge = "47.1.0"
 forgeSpi = "6.0.0"
 mixin = "0.8.5"
-parchment = "2023.06.26"
-parchmentMc = "1.19.4"
+parchment = "2023.08.20"
+parchmentMc = "1.20.1"
 
 # Normal dependencies
-asm = "9.3"
-autoService = "1.0.1"
+asm = "9.5"
+autoService = "1.1.1"
 checkerFramework = "3.32.0"
 cobalt = "0.7.3"
 cobalt-next = "0.7.4" # Not a real version, used to constrain the version we accept.
+commonsCli = "1.3.1"
 fastutil = "8.5.9"
 guava = "31.1-jre"
 jetbrainsAnnotations = "24.0.1"
@@ -29,8 +30,8 @@ jzlib = "1.1.3"
 kotlin = "1.8.10"
 kotlin-coroutines = "1.6.4"
 netty = "4.1.82.Final"
-nightConfig = "3.6.5"
-slf4j = "1.7.36"
+nightConfig = "3.6.7"
+slf4j = "2.0.1"
 
 # Minecraft mods
 emi = "1.0.8+1.20.1"
@@ -45,37 +46,40 @@ rubidium = "0.6.1"
 sodium = "mc1.20-0.4.10"
 
 # Testing
-byteBuddy = "1.14.2"
 hamcrest = "2.2"
-jqwik = "1.7.2"
-junit = "5.9.2"
+jqwik = "1.7.4"
+junit = "5.10.0"
 
 # Build tools
 cctJavadoc = "1.8.0"
-checkstyle = "10.3.4"
+checkstyle = "10.12.3"
 curseForgeGradle = "1.0.14"
-errorProne-core = "2.18.0"
-errorProne-plugin = "3.0.1"
+errorProne-core = "2.21.1"
+errorProne-plugin = "3.1.0"
 fabric-loom = "1.3.7"
 forgeGradle = "6.0.8"
-githubRelease = "2.2.12"
-ideaExt = "1.1.6"
-illuaminate = "0.1.0-40-g975cbc3"
+githubRelease = "2.4.1"
+ideaExt = "1.1.7"
+illuaminate = "0.1.0-44-g9ee0055"
 librarian = "1.+"
+lwjgl = "3.3.1"
 minotaur = "2.+"
 mixinGradle = "0.7.+"
 nullAway = "0.9.9"
-quiltflower = "1.10.0"
-spotless = "6.17.0"
+spotless = "6.21.0"
 taskTree = "2.1.1"
+teavm = "0.9.0-SQUID.1"
 vanillaGradle = "0.2.1-SNAPSHOT"
+vineflower = "1.11.0"
 
 [libraries]
 # Normal dependencies
 asm = { module = "org.ow2.asm:asm", version.ref = "asm" }
+asm-commons = { module = "org.ow2.asm:asm-commons", version.ref = "asm" }
 autoService = { module = "com.google.auto.service:auto-service", version.ref = "autoService" }
 checkerFramework = { module = "org.checkerframework:checker-qual", version.ref = "checkerFramework" }
 cobalt = { module = "org.squiddev:Cobalt", version.ref = "cobalt" }
+commonsCli = { module = "commons-cli:commons-cli", version.ref = "commonsCli" }
 fastutil = { module = "it.unimi.dsi:fastutil", version.ref = "fastutil" }
 forgeSpi = { module = "net.minecraftforge:forgespi", version.ref = "forgeSpi" }
 guava = { module = "com.google.guava:guava", version.ref = "guava" }
@@ -95,6 +99,7 @@ slf4j = { module = "org.slf4j:slf4j-api", version.ref = "slf4j" }
 # Minecraft mods
 fabric-api = { module = "net.fabricmc.fabric-api:fabric-api", version.ref = "fabric-api" }
 fabric-loader = { module = "net.fabricmc:fabric-loader", version.ref = "fabric-loader" }
+fabric-junit = { module = "net.fabricmc:fabric-loader-junit", version.ref = "fabric-loader" }
 fabricPermissions = { module = "me.lucko:fabric-permissions-api", version.ref = "fabricPermissions" }
 emi = { module = "dev.emi:emi-xplat-mojmap", version.ref = "emi" }
 iris = { module = "maven.modrinth:iris", version.ref = "iris" }
@@ -112,8 +117,6 @@ rubidium = { module = "maven.modrinth:rubidium", version.ref = "rubidium" }
 sodium = { module = "maven.modrinth:sodium", version.ref = "sodium" }
 
 # Testing
-byteBuddyAgent = { module = "net.bytebuddy:byte-buddy-agent", version.ref = "byteBuddy" }
-byteBuddy = { module = "net.bytebuddy:byte-buddy", version.ref = "byteBuddy" }
 hamcrest = { module = "org.hamcrest:hamcrest", version.ref = "hamcrest" }
 jqwik-api = { module = "net.jqwik:jqwik-api", version.ref = "jqwik" }
 jqwik-engine = { module = "net.jqwik:jqwik-engine", version.ref = "jqwik" }
@@ -122,6 +125,12 @@ junit-jupiter-engine = { module = "org.junit.jupiter:junit-jupiter-engine", vers
 junit-jupiter-params = { module = "org.junit.jupiter:junit-jupiter-params", version.ref = "junit" }
 slf4j-simple = { module = "org.slf4j:slf4j-simple", version.ref = "slf4j" }
 
+# LWJGL
+lwjgl-bom = { module = "org.lwjgl:lwjgl-bom", version.ref = "lwjgl" }
+lwjgl-core = { module = "org.lwjgl:lwjgl" }
+lwjgl-opengl = { module = "org.lwjgl:lwjgl-opengl" }
+lwjgl-glfw = { module = "org.lwjgl:lwjgl-glfw" }
+
 # Build tools
 cctJavadoc = { module = "cc.tweaked:cct-javadoc", version.ref = "cctJavadoc" }
 checkstyle = { module = "com.puppycrawl.tools:checkstyle", version.ref = "checkstyle" }
@@ -133,24 +142,33 @@ errorProne-plugin = { module = "net.ltgt.gradle:gradle-errorprone-plugin", versi
 errorProne-testHelpers = { module = "com.google.errorprone:error_prone_test_helpers", version.ref = "errorProne-core" }
 fabric-loom = { module = "net.fabricmc:fabric-loom", version.ref = "fabric-loom" }
 forgeGradle = { module = "net.minecraftforge.gradle:ForgeGradle", version.ref = "forgeGradle" }
+ideaExt = { module = "gradle.plugin.org.jetbrains.gradle.plugin.idea-ext:gradle-idea-ext", version.ref = "ideaExt" }
 kotlin-plugin = { module = "org.jetbrains.kotlin:kotlin-gradle-plugin", version.ref = "kotlin" }
 librarian = { module = "org.parchmentmc:librarian", version.ref = "librarian" }
 minotaur = { module = "com.modrinth.minotaur:Minotaur", version.ref = "minotaur" }
 nullAway = { module = "com.uber.nullaway:nullaway", version.ref = "nullAway" }
-quiltflower = { module = "io.github.juuxel:loom-quiltflower", version.ref = "quiltflower" }
 spotless = { module = "com.diffplug.spotless:spotless-plugin-gradle", version.ref = "spotless" }
+teavm-classlib = { module = "org.teavm:teavm-classlib", version.ref = "teavm" }
+teavm-jso = { module = "org.teavm:teavm-jso", version.ref = "teavm" }
+teavm-jso-apis = { module = "org.teavm:teavm-jso-apis", version.ref = "teavm" }
+teavm-jso-impl = { module = "org.teavm:teavm-jso-impl", version.ref = "teavm" }
+teavm-metaprogramming-api = { module = "org.teavm:teavm-metaprogramming-api", version.ref = "teavm" }
+teavm-metaprogramming-impl = { module = "org.teavm:teavm-metaprogramming-impl", version.ref = "teavm" }
+teavm-platform = { module = "org.teavm:teavm-platform", version.ref = "teavm" }
+teavm-tooling = { module = "org.teavm:teavm-tooling", version.ref = "teavm" }
 vanillaGradle = { module = "org.spongepowered:vanillagradle", version.ref = "vanillaGradle" }
+vineflower = { module = "io.github.juuxel:loom-vineflower", version.ref = "vineflower" }
 
 [plugins]
 forgeGradle = { id = "net.minecraftforge.gradle", version.ref = "forgeGradle" }
 githubRelease = { id = "com.github.breadmoirai.github-release", version.ref = "githubRelease" }
-ideaExt = { id = "org.jetbrains.gradle.plugin.idea-ext", version.ref = "ideaExt" }
 kotlin = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }
 librarian = { id = "org.parchmentmc.librarian.forgegradle", version.ref = "librarian" }
 mixinGradle = { id = "org.spongepowered.mixin", version.ref = "mixinGradle" }
 taskTree = { id = "com.dorongold.task-tree", version.ref = "taskTree" }
 
 [bundles]
+annotations = ["jsr305", "checkerFramework", "jetbrainsAnnotations"]
 kotlin = ["kotlin-stdlib", "kotlin-coroutines"]
 
 # Minecraft
@@ -164,3 +182,7 @@ externalMods-fabric-runtime = ["jei-fabric", "modmenu"]
 # Testing
 test = ["junit-jupiter-api", "junit-jupiter-params", "hamcrest", "jqwik-api"]
 testRuntime = ["junit-jupiter-engine", "jqwik-engine"]
+
+# Build tools
+teavm-api = [ "teavm-jso", "teavm-jso-apis", "teavm-platform", "teavm-classlib", "teavm-metaprogramming-api" ]
+teavm-tooling = [ "teavm-tooling", "teavm-metaprogramming-impl", "teavm-jso-impl" ]

illuaminate.sexp

@@ -2,7 +2,7 @@
 
 ; SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 ;
-; SPDX-License-Identifier: LicenseRef-CCPL
+; SPDX-License-Identifier: MPL-2.0
 
 (sources
   /doc/
@@ -10,7 +10,7 @@
   /projects/core/src/main/resources/data/computercraft/lua/bios.lua
   /projects/core/src/main/resources/data/computercraft/lua/rom/
   /projects/core/src/test/resources/test-rom
-  /projects/web/src/mount)
+  /projects/web/src/frontend/mount)
 
 (doc
   ; Also defined in projects/web/build.gradle.kts
@@ -23,7 +23,7 @@
     (url https://tweaked.cc/)
     (source-link https://github.com/cc-tweaked/CC-Tweaked/blob/${commit}/${path}#L${line})
 
-    (styles /projects/web/src/styles.css)
+    (styles  /projects/web/build/rollup/index.css)
     (scripts /projects/web/build/rollup/index.js)
     (head doc/head.html))
 
@@ -77,7 +77,6 @@
     (globals
       :max
       _CC_DEFAULT_SETTINGS
-      _CC_DISABLE_LUA51_FEATURES
       _HOST
       ;; Ideally we'd pick these up from bios.lua, but illuaminate currently
       ;; isn't smart enough.
@@ -115,4 +114,4 @@
       :max sleep write
       cct_test describe expect howlci fail it pending stub before_each)))
 
-(at /projects/web/src/mount/expr_template.lua (lint (globals :max __expr__)))
+(at /projects/web/src/frontend/mount/expr_template.lua (lint (globals :max __expr__)))

package.json

@@ -6,24 +6,24 @@
   "license": "BSD-3-Clause",
   "type": "module",
   "dependencies": {
+    "@squid-dev/cc-web-term": "^2.0.0",
     "preact": "^10.5.5",
+    "setimmediate": "^1.0.5",
     "tslib": "^2.0.3"
   },
   "devDependencies": {
-    "@rollup/plugin-terser": "^0.4.0",
+    "@rollup/plugin-node-resolve": "^15.2.1",
     "@rollup/plugin-typescript": "^11.0.0",
     "@rollup/plugin-url": "^8.0.1",
-    "@types/glob": "^8.1.0",
-    "@types/react-dom": "^18.0.5",
-    "glob": "^9.3.0",
-    "react-dom": "^18.1.0",
-    "react": "^18.1.0",
-    "rehype-highlight": "^6.0.0",
-    "rehype-react": "^7.1.1",
-    "rehype": "^12.0.1",
-    "requirejs": "^2.3.6",
-    "rollup": "^3.19.1",
-    "ts-node": "^10.8.0",
-    "typescript": "^4.0.5"
+    "@swc/core": "^1.3.92",
+    "@types/node": "^20.8.3",
+    "lightningcss": "^1.22.0",
+    "preact-render-to-string": "^6.2.1",
+    "rehype": "^13.0.0",
+    "rehype-highlight": "^7.0.0",
+    "rehype-react": "^8.0.0",
+    "rollup": "^4.0.0",
+    "tsx": "^3.12.10",
+    "typescript": "^5.2.2"
   }
 }

projects/ARCHITECTURE.md

@@ -62,6 +62,9 @@ mentioning:
  - `lints`: This defines an [ErrorProne] plugin which adds a couple of compile-time checks to our code. This is what
    enforces that no client-specific code is used inside the `main` source set (and a couple of other things!).
 
+ - `standalone`: This contains a standalone UI for computers, allowing debugging and development of CraftOS without
+   launching Minecraft.
+
  - `web`: This contains the additional tooling for building [the documentation website][tweaked.cc], such as support for
    rendering recipes
 

projects/common-api/src/client/java/dan200/computercraft/api/client/turtle/TurtleUpgradeModellers.java

@@ -17,7 +17,7 @@ import org.joml.Matrix4f;
 
 import javax.annotation.Nullable;
 
-class TurtleUpgradeModellers {
+final class TurtleUpgradeModellers {
     private static final Transformation leftTransform = getMatrixFor(-0.4065f);
     private static final Transformation rightTransform = getMatrixFor(0.4065f);
 
@@ -35,7 +35,7 @@ class TurtleUpgradeModellers {
 
     static final TurtleUpgradeModeller<ITurtleUpgrade> UPGRADE_ITEM = new UpgradeItemModeller();
 
-    private static class UpgradeItemModeller implements TurtleUpgradeModeller<ITurtleUpgrade> {
+    private static final class UpgradeItemModeller implements TurtleUpgradeModeller<ITurtleUpgrade> {
         @Override
         public TransformedModel getModel(ITurtleUpgrade upgrade, @Nullable ITurtleAccess turtle, TurtleSide side) {
             return getModel(turtle == null ? upgrade.getCraftingItem() : upgrade.getUpgradeItem(turtle.getUpgradeNBTData(side)), side);

projects/common-api/src/main/java/dan200/computercraft/api/ComputerCraftTags.java

@@ -46,6 +46,14 @@ public class ComputerCraftTags {
         public static final TagKey<Block> WIRED_MODEM = make("wired_modem");
         public static final TagKey<Block> MONITOR = make("monitor");
 
+        /**
+         * Blocks which should be ignored by a {@code peripheral_hub} peripheral.
+         * <p>
+         * This should include blocks which themselves expose a peripheral hub (such as {@linkplain #WIRED_MODEM wired
+         * modems}).
+         */
+        public static final TagKey<Block> PERIPHERAL_HUB_IGNORE = make("peripheral_hub_ignore");
+
         /**
          * Blocks which can be broken by any turtle tool.
          */

projects/common-api/src/main/java/dan200/computercraft/api/upgrades/UpgradeDataProvider.java

@@ -19,8 +19,6 @@ import net.minecraft.data.PackOutput;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.Item;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 
 import javax.annotation.Nullable;
 import java.util.*;
@@ -36,8 +34,6 @@ import java.util.function.Function;
  * @param <R> The upgrade serialiser to register for.
  */
 public abstract class UpgradeDataProvider<T extends UpgradeBase, R extends UpgradeSerialiser<? extends T>> implements DataProvider {
-    private static final Logger LOGGER = LogManager.getLogger();
-
     private final PackOutput output;
     private final String name;
     private final String folder;

projects/common/build.gradle.kts

@@ -7,9 +7,9 @@ import cc.tweaked.gradle.clientClasses
 import cc.tweaked.gradle.commonClasses
 
 plugins {
-    id("cc-tweaked.publishing")
     id("cc-tweaked.vanilla")
     id("cc-tweaked.gametest")
+    id("cc-tweaked.publishing")
 }
 
 minecraft {
@@ -39,4 +39,6 @@ dependencies {
     testModImplementation(testFixtures(project(":core")))
     testModImplementation(testFixtures(project(":common")))
     testModImplementation(libs.bundles.kotlin)
+
+    testFixturesImplementation(testFixtures(project(":core")))
 }

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

@@ -33,7 +33,6 @@ import java.nio.ByteBuffer;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
@@ -219,7 +218,7 @@ public abstract class AbstractComputerScreen<T extends AbstractComputerMenu> ext
 
     private void alert(Component title, Component message) {
         OptionScreen.show(minecraft, title, message,
-            Collections.singletonList(OptionScreen.newButton(OK, b -> minecraft.setScreen(this))),
+            List.of(OptionScreen.newButton(OK, b -> minecraft.setScreen(this))),
             () -> minecraft.setScreen(this)
         );
     }

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

@@ -1,6 +1,6 @@
 // SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers
 //
-// SPDX-License-Identifier: LicenseRef-CCPL
+// SPDX-License-Identifier: MPL-2.0
 
 package dan200.computercraft.client.gui;
 

projects/common/src/client/java/dan200/computercraft/client/integration/ShaderMod.java

@@ -47,7 +47,7 @@ public class ShaderMod {
         Optional<ShaderMod> get();
     }
 
-    private static class Storage {
+    private static final class Storage {
         static final ShaderMod INSTANCE = ServiceLoader.load(Provider.class)
             .stream()
             .flatMap(x -> x.get().get().stream())

projects/common/src/client/java/dan200/computercraft/client/render/monitor/MonitorTextureBufferShader.java

@@ -14,10 +14,10 @@ import dan200.computercraft.core.terminal.TextBuffer;
 import dan200.computercraft.core.util.Colour;
 import net.minecraft.client.renderer.ShaderInstance;
 import net.minecraft.server.packs.resources.ResourceProvider;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.lwjgl.opengl.GL13;
 import org.lwjgl.opengl.GL31;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import javax.annotation.Nullable;
 import java.io.IOException;
@@ -36,12 +36,12 @@ import static dan200.computercraft.client.render.text.FixedWidthFontRenderer.get
  * @see RenderTypes#getMonitorTextureBufferShader()
  */
 public class MonitorTextureBufferShader extends ShaderInstance {
+    private static final Logger LOG = LoggerFactory.getLogger(MonitorTextureBufferShader.class);
+
     public static final int UNIFORM_SIZE = 4 * 4 * 16 + 4 + 4 + 2 * 4 + 4;
 
     static final int TEXTURE_INDEX = GL13.GL_TEXTURE3;
 
-    private static final Logger LOGGER = LogManager.getLogger();
-
     private final int monitorData;
     private int uniformBuffer = 0;
 
@@ -75,7 +75,7 @@ public class MonitorTextureBufferShader extends ShaderInstance {
     private Uniform getUniformChecked(String name) {
         var uniform = getUniform(name);
         if (uniform == null) {
-            LOGGER.warn("Monitor shader {} should have uniform {}, but it was not present.", getName(), name);
+            LOG.warn("Monitor shader {} should have uniform {}, but it was not present.", getName(), name);
         }
 
         return uniform;

projects/common/src/main/java/dan200/computercraft/data/LanguageProvider.java

@@ -139,8 +139,6 @@ public final class LanguageProvider implements DataProvider {
         add("commands.computercraft.tp.synopsis", "Teleport to a specific computer.");
         add("commands.computercraft.tp.desc", "Teleport to the location of a computer. You can either specify the computer's instance id (e.g. 123) or computer id (e.g #123).");
         add("commands.computercraft.tp.action", "Teleport to this computer");
-        add("commands.computercraft.tp.not_player", "Cannot open terminal for non-player");
-        add("commands.computercraft.tp.not_there", "Cannot locate computer in the world");
         add("commands.computercraft.view.synopsis", "View the terminal of a computer.");
         add("commands.computercraft.view.desc", "Open the terminal of a computer, allowing remote control of a computer. This does not provide access to turtle's inventories. You can either specify the computer's instance id (e.g. 123) or computer id (e.g #123).");
         add("commands.computercraft.view.action", "View this computer");
@@ -215,7 +213,6 @@ public final class LanguageProvider implements DataProvider {
         addConfigEntry(ConfigSpec.floppySpaceLimit, "Floppy Disk space limit (bytes)");
         addConfigEntry(ConfigSpec.uploadMaxSize, "File upload size limit (bytes)");
         addConfigEntry(ConfigSpec.maximumFilesOpen, "Maximum files open per computer");
-        addConfigEntry(ConfigSpec.disableLua51Features, "Disable Lua 5.1 features");
         addConfigEntry(ConfigSpec.defaultComputerSettings, "Default Computer settings");
         addConfigEntry(ConfigSpec.logComputerErrors, "Log computer errors");
         addConfigEntry(ConfigSpec.commandRequireCreative, "Command computers require creative");

projects/common/src/main/java/dan200/computercraft/data/RecipeProvider.java

@@ -5,6 +5,7 @@
 package dan200.computercraft.data;
 
 import com.google.gson.JsonObject;
+import com.mojang.authlib.GameProfile;
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.pocket.PocketUpgradeDataProvider;
 import dan200.computercraft.api.turtle.TurtleUpgradeDataProvider;
@@ -25,15 +26,12 @@ import net.minecraft.core.registries.Registries;
 import net.minecraft.data.PackOutput;
 import net.minecraft.data.recipes.*;
 import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.NbtUtils;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.tags.TagKey;
 import net.minecraft.util.GsonHelper;
-import net.minecraft.world.item.DyeColor;
-import net.minecraft.world.item.DyeItem;
-import net.minecraft.world.item.Item;
-import net.minecraft.world.item.Items;
+import net.minecraft.world.item.*;
 import net.minecraft.world.item.crafting.Ingredient;
-import net.minecraft.world.item.crafting.RecipeSerializer;
 import net.minecraft.world.item.crafting.ShapedRecipe;
 import net.minecraft.world.item.crafting.SimpleCraftingRecipeSerializer;
 import net.minecraft.world.level.ItemLike;
@@ -41,6 +39,7 @@ import net.minecraft.world.level.block.Blocks;
 
 import java.util.List;
 import java.util.Locale;
+import java.util.UUID;
 import java.util.function.Consumer;
 
 import static dan200.computercraft.api.ComputerCraftTags.Items.COMPUTER;
@@ -443,7 +442,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .requires(ModRegistry.Items.MONITOR_NORMAL.get())
             .unlockedBy("has_monitor", inventoryChange(ModRegistry.Items.MONITOR_NORMAL.get()))
             .save(
-                RecipeWrapper.wrap(RecipeSerializer.SHAPELESS_RECIPE, add)
+                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.SHAPELESS.get(), add)
                     .withResultTag(playerHead("Cloudhunter", "6d074736-b1e9-4378-a99b-bd8777821c9c")),
                 new ResourceLocation(ComputerCraftAPI.MOD_ID, "skull_cloudy")
             );
@@ -454,7 +453,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .requires(ModRegistry.Items.COMPUTER_ADVANCED.get())
             .unlockedBy("has_computer", inventoryChange(ModRegistry.Items.COMPUTER_ADVANCED.get()))
             .save(
-                RecipeWrapper.wrap(RecipeSerializer.SHAPELESS_RECIPE, add)
+                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.SHAPELESS.get(), add)
                     .withResultTag(playerHead("dan200", "f3c8d69b-0776-4512-8434-d1b2165909eb")),
                 new ResourceLocation(ComputerCraftAPI.MOD_ID, "skull_dan200")
             );
@@ -513,17 +512,15 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
     }
 
     private static CompoundTag playerHead(String name, String uuid) {
-        var owner = new CompoundTag();
-        owner.putString("Name", name);
-        owner.putString("Id", uuid);
+        var owner = NbtUtils.writeGameProfile(new CompoundTag(), new GameProfile(UUID.fromString(uuid), name));
 
         var tag = new CompoundTag();
-        tag.put("SkullOwner", owner);
+        tag.put(PlayerHeadItem.TAG_SKULL_OWNER, owner);
         return tag;
     }
 
     private static Consumer<JsonObject> family(ComputerFamily family) {
-        return json -> json.addProperty("family", family.toString());
+        return json -> json.addProperty("family", family.getSerializedName());
     }
 
     private static void addSpecial(Consumer<FinishedRecipe> add, SimpleCraftingRecipeSerializer<?> special) {

projects/common/src/main/java/dan200/computercraft/data/TagProvider.java

@@ -35,6 +35,8 @@ class TagProvider {
         tags.tag(ComputerCraftTags.Blocks.WIRED_MODEM).add(ModRegistry.Blocks.CABLE.get(), ModRegistry.Blocks.WIRED_MODEM_FULL.get());
         tags.tag(ComputerCraftTags.Blocks.MONITOR).add(ModRegistry.Blocks.MONITOR_NORMAL.get(), ModRegistry.Blocks.MONITOR_ADVANCED.get());
 
+        tags.tag(ComputerCraftTags.Blocks.PERIPHERAL_HUB_IGNORE).addTag(ComputerCraftTags.Blocks.WIRED_MODEM);
+
         tags.tag(ComputerCraftTags.Blocks.TURTLE_ALWAYS_BREAKABLE).addTag(BlockTags.LEAVES).add(
             Blocks.BAMBOO, Blocks.BAMBOO_SAPLING // Bamboo isn't instabreak for some odd reason.
         );

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

@@ -18,8 +18,8 @@ import net.minecraft.server.packs.resources.SimpleJsonResourceReloadListener;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.util.profiling.ProfilerFiller;
 import net.minecraft.world.item.ItemStack;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import javax.annotation.Nullable;
 import java.util.Collection;
@@ -37,7 +37,7 @@ import java.util.stream.Collectors;
  * @see PocketUpgrades
  */
 public class UpgradeManager<R extends UpgradeSerialiser<? extends T>, T extends UpgradeBase> extends SimpleJsonResourceReloadListener {
-    private static final Logger LOGGER = LogManager.getLogger();
+    private static final Logger LOG = LoggerFactory.getLogger(UpgradeManager.class);
     private static final Gson GSON = new GsonBuilder().setPrettyPrinting().disableHtmlEscaping().create();
 
     public record UpgradeWrapper<R extends UpgradeSerialiser<? extends T>, T extends UpgradeBase>(
@@ -48,8 +48,8 @@ public class UpgradeManager<R extends UpgradeSerialiser<? extends T>, T extends
     private final String kind;
     private final ResourceKey<Registry<R>> registry;
 
-    private Map<String, UpgradeWrapper<R, T>> current = Collections.emptyMap();
-    private Map<T, UpgradeWrapper<R, T>> currentWrappers = Collections.emptyMap();
+    private Map<String, UpgradeWrapper<R, T>> current = Map.of();
+    private Map<T, UpgradeWrapper<R, T>> currentWrappers = Map.of();
 
     public UpgradeManager(String kind, String path, ResourceKey<Registry<R>> registry) {
         super(GSON, path);
@@ -103,13 +103,13 @@ public class UpgradeManager<R extends UpgradeSerialiser<? extends T>, T extends
             try {
                 loadUpgrade(newUpgrades, element.getKey(), element.getValue());
             } catch (IllegalArgumentException | JsonParseException e) {
-                LOGGER.error("Error loading {} {} from JSON file", kind, element.getKey(), e);
+                LOG.error("Error loading {} {} from JSON file", kind, element.getKey(), e);
             }
         }
 
         current = Collections.unmodifiableMap(newUpgrades);
         currentWrappers = newUpgrades.values().stream().collect(Collectors.toUnmodifiableMap(UpgradeWrapper::upgrade, x -> x));
-        LOGGER.info("Loaded {} {}s", current.size(), kind);
+        LOG.info("Loaded {} {}s", current.size(), kind);
     }
 
     private void loadUpgrade(Map<String, UpgradeWrapper<R, T>> current, ResourceLocation id, JsonElement json) {

projects/common/src/main/java/dan200/computercraft/impl/network/wired/WiredNetworkChangeImpl.java

@@ -12,7 +12,7 @@ import java.util.HashMap;
 import java.util.Map;
 
 final class WiredNetworkChangeImpl implements WiredNetworkChange {
-    private static final WiredNetworkChangeImpl EMPTY = new WiredNetworkChangeImpl(Collections.emptyMap(), Collections.emptyMap());
+    private static final WiredNetworkChangeImpl EMPTY = new WiredNetworkChangeImpl(Map.of(), Map.of());
 
     private final Map<String, IPeripheral> removed;
     private final Map<String, IPeripheral> added;
@@ -27,11 +27,11 @@ final class WiredNetworkChangeImpl implements WiredNetworkChange {
     }
 
     static WiredNetworkChangeImpl added(Map<String, IPeripheral> added) {
-        return added.isEmpty() ? EMPTY : new WiredNetworkChangeImpl(Collections.emptyMap(), Collections.unmodifiableMap(added));
+        return added.isEmpty() ? EMPTY : new WiredNetworkChangeImpl(Map.of(), Collections.unmodifiableMap(added));
     }
 
     static WiredNetworkChangeImpl removed(Map<String, IPeripheral> removed) {
-        return removed.isEmpty() ? EMPTY : new WiredNetworkChangeImpl(Collections.unmodifiableMap(removed), Collections.emptyMap());
+        return removed.isEmpty() ? EMPTY : new WiredNetworkChangeImpl(Collections.unmodifiableMap(removed), Map.of());
     }
 
     static WiredNetworkChangeImpl changeOf(Map<String, IPeripheral> oldPeripherals, Map<String, IPeripheral> newPeripherals) {
@@ -39,9 +39,9 @@ final class WiredNetworkChangeImpl implements WiredNetworkChange {
         if (oldPeripherals.isEmpty() && newPeripherals.isEmpty()) {
             return EMPTY;
         } else if (oldPeripherals.isEmpty()) {
-            return new WiredNetworkChangeImpl(Collections.emptyMap(), newPeripherals);
+            return new WiredNetworkChangeImpl(Map.of(), newPeripherals);
         } else if (newPeripherals.isEmpty()) {
-            return new WiredNetworkChangeImpl(oldPeripherals, Collections.emptyMap());
+            return new WiredNetworkChangeImpl(oldPeripherals, Map.of());
         }
 
         Map<String, IPeripheral> added = new HashMap<>(newPeripherals);

projects/common/src/main/java/dan200/computercraft/impl/network/wired/WiredNetworkImpl.java

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.impl.network.wired;
 
-import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.api.network.Packet;
 import dan200.computercraft.api.network.wired.WiredNetwork;
 import dan200.computercraft.api.network.wired.WiredNode;
@@ -24,7 +23,7 @@ final class WiredNetworkImpl implements WiredNetwork {
         nodes.add(node);
     }
 
-    private WiredNetworkImpl(HashSet<WiredNodeImpl> nodes) {
+    private WiredNetworkImpl(Set<WiredNodeImpl> nodes) {
         this.nodes = nodes;
     }
 
@@ -57,10 +56,10 @@ final class WiredNetworkImpl implements WiredNetwork {
                     // Move all nodes across into this network, destroying the original nodes.
                     nodes.addAll(otherNodes);
                     for (var node : otherNodes) node.network = this;
-                    other.nodes = Collections.emptySet();
+                    other.nodes = Set.of();
 
                     // Move all peripherals across,
-                    other.peripherals = Collections.emptyMap();
+                    other.peripherals = Map.of();
                     peripherals.putAll(otherPeripherals);
 
                     if (!thisPeripherals.isEmpty()) {
@@ -217,7 +216,7 @@ final class WiredNetworkImpl implements WiredNetwork {
             try {
                 // We special case the original node: detaching all peripherals when needed.
                 wired.network = wiredNetwork;
-                wired.peripherals = Collections.emptyMap();
+                wired.peripherals = Map.of();
 
                 // Ensure every network is finalised
                 for (var network : maximals) {
@@ -260,7 +259,7 @@ final class WiredNetworkImpl implements WiredNetwork {
             var change = WiredNetworkChangeImpl.changeOf(oldPeripherals, newPeripherals);
             if (change.isEmpty()) return;
 
-            wired.peripherals = ImmutableMap.copyOf(newPeripherals);
+            wired.peripherals = Map.copyOf(newPeripherals);
 
             // Detach the old peripherals then remove them.
             peripherals.keySet().removeAll(change.peripheralsRemoved().keySet());
@@ -333,7 +332,7 @@ final class WiredNetworkImpl implements WiredNetwork {
             // Detach the old peripherals then remove them from the old network
             wired.network = wiredNetwork;
             wired.neighbours.clear();
-            wired.peripherals = Collections.emptyMap();
+            wired.peripherals = Map.of();
 
             // Broadcast the change
             if (!peripherals.isEmpty()) WiredNetworkChangeImpl.removed(peripherals).broadcast(wired);
@@ -375,7 +374,7 @@ final class WiredNetworkImpl implements WiredNetwork {
         }
     }
 
-    private static HashSet<WiredNodeImpl> reachableNodes(WiredNodeImpl start) {
+    private static Set<WiredNodeImpl> reachableNodes(WiredNodeImpl start) {
         Queue<WiredNodeImpl> enqueued = new ArrayDeque<>();
         var reachable = new HashSet<WiredNodeImpl>();
 

projects/common/src/main/java/dan200/computercraft/impl/network/wired/WiredNodeImpl.java

@@ -13,13 +13,16 @@ import dan200.computercraft.api.network.wired.WiredSender;
 import dan200.computercraft.api.peripheral.IPeripheral;
 
 import javax.annotation.Nullable;
-import java.util.*;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
 
 public final class WiredNodeImpl implements WiredNode {
     private @Nullable Set<PacketReceiver> receivers;
 
     final WiredElement element;
-    Map<String, IPeripheral> peripherals = Collections.emptyMap();
+    Map<String, IPeripheral> peripherals = Map.of();
 
     final HashSet<WiredNodeImpl> neighbours = new HashSet<>();
     volatile WiredNetworkImpl network;

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

@@ -24,12 +24,14 @@ import dan200.computercraft.shared.common.ClearColourRecipe;
 import dan200.computercraft.shared.common.ColourableRecipe;
 import dan200.computercraft.shared.common.DefaultBundledRedstoneProvider;
 import dan200.computercraft.shared.common.HeldItemMenu;
+import dan200.computercraft.shared.computer.blocks.CommandComputerBlock;
 import dan200.computercraft.shared.computer.blocks.CommandComputerBlockEntity;
 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.inventory.ComputerMenuWithoutInventory;
 import dan200.computercraft.shared.computer.inventory.ViewComputerMenu;
+import dan200.computercraft.shared.computer.items.CommandComputerItem;
 import dan200.computercraft.shared.computer.items.ComputerItem;
 import dan200.computercraft.shared.computer.recipe.ComputerUpgradeRecipe;
 import dan200.computercraft.shared.data.BlockNamedEntityLootCondition;
@@ -68,6 +70,10 @@ import dan200.computercraft.shared.pocket.items.PocketComputerItem;
 import dan200.computercraft.shared.pocket.peripherals.PocketModem;
 import dan200.computercraft.shared.pocket.peripherals.PocketSpeaker;
 import dan200.computercraft.shared.pocket.recipes.PocketComputerUpgradeRecipe;
+import dan200.computercraft.shared.recipe.CustomShapedRecipe;
+import dan200.computercraft.shared.recipe.CustomShapelessRecipe;
+import dan200.computercraft.shared.recipe.ImpostorShapedRecipe;
+import dan200.computercraft.shared.recipe.ImpostorShapelessRecipe;
 import dan200.computercraft.shared.turtle.FurnaceRefuelHandler;
 import dan200.computercraft.shared.turtle.blocks.TurtleBlock;
 import dan200.computercraft.shared.turtle.blocks.TurtleBlockEntity;
@@ -77,8 +83,6 @@ 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.ImpostorRecipe;
-import dan200.computercraft.shared.util.ImpostorShapelessRecipe;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.commands.synchronization.ArgumentTypeInfo;
 import net.minecraft.commands.synchronization.SingletonArgumentInfo;
@@ -139,7 +143,7 @@ public final class ModRegistry {
         public static final RegistryEntry<ComputerBlock<ComputerBlockEntity>> COMPUTER_ADVANCED = REGISTRY.register("computer_advanced",
             () -> new ComputerBlock<>(computerProperties().mapColor(MapColor.GOLD), ComputerFamily.ADVANCED, BlockEntities.COMPUTER_ADVANCED));
 
-        public static final RegistryEntry<ComputerBlock<CommandComputerBlockEntity>> COMPUTER_COMMAND = REGISTRY.register("computer_command", () -> new ComputerBlock<>(
+        public static final RegistryEntry<ComputerBlock<CommandComputerBlockEntity>> COMPUTER_COMMAND = REGISTRY.register("computer_command", () -> new CommandComputerBlock<>(
             computerProperties().strength(-1, 6000000.0F),
             ComputerFamily.COMMAND, BlockEntities.COMPUTER_COMMAND
         ));
@@ -222,7 +226,7 @@ public final class ModRegistry {
 
         public static final RegistryEntry<ComputerItem> COMPUTER_NORMAL = ofBlock(Blocks.COMPUTER_NORMAL, ComputerItem::new);
         public static final RegistryEntry<ComputerItem> COMPUTER_ADVANCED = ofBlock(Blocks.COMPUTER_ADVANCED, ComputerItem::new);
-        public static final RegistryEntry<ComputerItem> COMPUTER_COMMAND = ofBlock(Blocks.COMPUTER_COMMAND, ComputerItem::new);
+        public static final RegistryEntry<ComputerItem> COMPUTER_COMMAND = ofBlock(Blocks.COMPUTER_COMMAND, CommandComputerItem::new);
 
         public static final RegistryEntry<PocketComputerItem> POCKET_COMPUTER_NORMAL = REGISTRY.register("pocket_computer_normal",
             () -> new PocketComputerItem(properties().stacksTo(1), ComputerFamily.NORMAL));
@@ -357,17 +361,21 @@ public final class ModRegistry {
             return REGISTRY.register(name, () -> new SimpleCraftingRecipeSerializer<>(factory));
         }
 
+        public static final RegistryEntry<RecipeSerializer<CustomShapedRecipe>> SHAPED = REGISTRY.register("shaped", () -> CustomShapedRecipe.serialiser(CustomShapedRecipe::new));
+        public static final RegistryEntry<RecipeSerializer<CustomShapelessRecipe>> SHAPELESS = REGISTRY.register("shapeless", () -> CustomShapelessRecipe.serialiser(CustomShapelessRecipe::new));
+
+        public static final RegistryEntry<RecipeSerializer<ImpostorShapedRecipe>> IMPOSTOR_SHAPED = REGISTRY.register("impostor_shaped", () -> CustomShapedRecipe.serialiser(ImpostorShapedRecipe::new));
+        public static final RegistryEntry<RecipeSerializer<ImpostorShapelessRecipe>> IMPOSTOR_SHAPELESS = REGISTRY.register("impostor_shapeless", () -> CustomShapelessRecipe.serialiser(ImpostorShapelessRecipe::new));
+
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<ColourableRecipe>> DYEABLE_ITEM = simple("colour", ColourableRecipe::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<ClearColourRecipe>> DYEABLE_ITEM_CLEAR = simple("clear_colour", ClearColourRecipe::new);
-        public static final RegistryEntry<TurtleRecipe.Serializer> TURTLE = REGISTRY.register("turtle", TurtleRecipe.Serializer::new);
+        public static final RegistryEntry<RecipeSerializer<TurtleRecipe>> TURTLE = REGISTRY.register("turtle", () -> TurtleRecipe.validatingSerialiser(TurtleRecipe::of));
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<TurtleUpgradeRecipe>> TURTLE_UPGRADE = simple("turtle_upgrade", TurtleUpgradeRecipe::new);
-        public static final RegistryEntry<TurtleOverlayRecipe.Serializer> TURTLE_OVERLAY = REGISTRY.register("turtle_overlay", TurtleOverlayRecipe.Serializer::new);
+        public static final RegistryEntry<RecipeSerializer<TurtleOverlayRecipe>> TURTLE_OVERLAY = REGISTRY.register("turtle_overlay", TurtleOverlayRecipe.Serializer::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<PocketComputerUpgradeRecipe>> POCKET_COMPUTER_UPGRADE = simple("pocket_computer_upgrade", PocketComputerUpgradeRecipe::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<PrintoutRecipe>> PRINTOUT = simple("printout", PrintoutRecipe::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<DiskRecipe>> DISK = simple("disk", DiskRecipe::new);
-        public static final RegistryEntry<ComputerUpgradeRecipe.Serializer> COMPUTER_UPGRADE = REGISTRY.register("computer_upgrade", ComputerUpgradeRecipe.Serializer::new);
-        public static final RegistryEntry<ImpostorRecipe.Serializer> IMPOSTOR_SHAPED = REGISTRY.register("impostor_shaped", ImpostorRecipe.Serializer::new);
-        public static final RegistryEntry<ImpostorShapelessRecipe.Serializer> IMPOSTOR_SHAPELESS = REGISTRY.register("impostor_shapeless", ImpostorShapelessRecipe.Serializer::new);
+        public static final RegistryEntry<RecipeSerializer<ComputerUpgradeRecipe>> COMPUTER_UPGRADE = REGISTRY.register("computer_upgrade", ComputerUpgradeRecipe.Serializer::new);
     }
 
     public static class Permissions {

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

@@ -26,7 +26,6 @@ import dan200.computercraft.shared.network.container.ComputerContainerData;
 import net.minecraft.commands.CommandSourceStack;
 import net.minecraft.core.BlockPos;
 import net.minecraft.network.chat.Component;
-import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.MenuProvider;
 import net.minecraft.world.entity.RelativeMovement;
 import net.minecraft.world.entity.player.Inventory;
@@ -34,13 +33,15 @@ 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;
 
 import javax.annotation.Nullable;
 import java.io.File;
 import java.util.*;
 
 import static dan200.computercraft.shared.command.CommandUtils.isPlayer;
-import static dan200.computercraft.shared.command.Exceptions.*;
+import static dan200.computercraft.shared.command.Exceptions.NOT_TRACKING_EXCEPTION;
+import static dan200.computercraft.shared.command.Exceptions.NO_TIMINGS_EXCEPTION;
 import static dan200.computercraft.shared.command.arguments.ComputerArgumentType.getComputerArgument;
 import static dan200.computercraft.shared.command.arguments.ComputerArgumentType.oneComputer;
 import static dan200.computercraft.shared.command.arguments.ComputersArgumentType.*;
@@ -62,15 +63,65 @@ public final class CommandComputerCraft {
         dispatcher.register(choice("computercraft")
             .then(literal("dump")
                 .requires(ModRegistry.Permissions.PERMISSION_DUMP)
-                .executes(context -> {
+                .executes(c -> dump(c.getSource()))
+                .then(args()
+                    .arg("computer", oneComputer())
+                    .executes(c -> dumpComputer(c.getSource(), getComputerArgument(c, "computer")))))
+
+            .then(command("shutdown")
+                .requires(ModRegistry.Permissions.PERMISSION_SHUTDOWN)
+                .argManyValue("computers", manyComputers(), s -> ServerContext.get(s.getServer()).registry().getComputers())
+                .executes((c, a) -> shutdown(c.getSource(), unwrap(c.getSource(), a))))
+
+            .then(command("turn-on")
+                .requires(ModRegistry.Permissions.PERMISSION_TURN_ON)
+                .argManyValue("computers", manyComputers(), s -> ServerContext.get(s.getServer()).registry().getComputers())
+                .executes((c, a) -> turnOn(c.getSource(), unwrap(c.getSource(), a))))
+
+            .then(command("tp")
+                .requires(ModRegistry.Permissions.PERMISSION_TP)
+                .arg("computer", oneComputer())
+                .executes(c -> teleport(c.getSource(), getComputerArgument(c, "computer"))))
+
+            .then(command("queue")
+                .requires(ModRegistry.Permissions.PERMISSION_QUEUE)
+                .arg(
+                    RequiredArgumentBuilder.<CommandSourceStack, ComputersArgumentType.ComputersSupplier>argument("computer", manyComputers())
+                        .suggests((context, builder) -> Suggestions.empty())
+                )
+                .argManyValue("args", StringArgumentType.string(), List.of())
+                .executes((c, a) -> queue(getComputersArgument(c, "computer"), a)))
+
+            .then(command("view")
+                .requires(ModRegistry.Permissions.PERMISSION_VIEW)
+                .arg("computer", oneComputer())
+                .executes(c -> view(c.getSource(), getComputerArgument(c, "computer"))))
+
+            .then(choice("track")
+                .requires(ModRegistry.Permissions.PERMISSION_TRACK)
+                .then(command("start").executes(c -> trackStart(c.getSource())))
+                .then(command("stop").executes(c -> trackStop(c.getSource())))
+                .then(command("dump")
+                    .argManyValue("fields", metric(), DEFAULT_FIELDS)
+                    .executes((c, f) -> trackDump(c.getSource(), f))))
+        );
+    }
+
+    /**
+     * Display loaded computers to a table.
+     *
+     * @param source The thing that executed this command.
+     * @return The number of loaded computers.
+     */
+    private static int dump(CommandSourceStack source) {
         var table = new TableBuilder("DumpAll", "Computer", "On", "Position");
 
-                    var source = context.getSource();
         List<ServerComputer> computers = new ArrayList<>(ServerContext.get(source.getServer()).registry().getComputers());
 
         Level world = source.getLevel();
         var pos = BlockPos.containing(source.getPosition());
 
+        // Sort by nearby computers.
         computers.sort((a, b) -> {
             if (a.getLevel() == b.getLevel() && a.getLevel() == world) {
                 return Double.compare(a.getPosition().distSqr(pos), b.getPosition().distSqr(pos));
@@ -91,20 +142,24 @@ public final class CommandComputerCraft {
             );
         }
 
-                    table.display(context.getSource());
+        table.display(source);
         return computers.size();
-                })
-                .then(args()
-                    .arg("computer", oneComputer())
-                    .executes(context -> {
-                        var computer = getComputerArgument(context, "computer");
+    }
 
+    /**
+     * Display additional information about a single computer.
+     *
+     * @param source   The thing that executed this command.
+     * @param computer The computer we're dumping.
+     * @return The constant {@code 1}.
+     */
+    private static int dumpComputer(CommandSourceStack source, ServerComputer computer) {
         var table = new TableBuilder("Dump");
         table.row(header("Instance"), text(Integer.toString(computer.getInstanceID())));
         table.row(header("Id"), text(Integer.toString(computer.getID())));
         table.row(header("Label"), text(computer.getLabel()));
         table.row(header("On"), bool(computer.isOn()));
-                        table.row(header("Position"), linkPosition(context.getSource(), computer));
+        table.row(header("Position"), linkPosition(source, computer));
         table.row(header("Family"), text(computer.getFamily().toString()));
 
         for (var side : ComputerSide.values()) {
@@ -114,76 +169,71 @@ public final class CommandComputerCraft {
             }
         }
 
-                        table.display(context.getSource());
+        table.display(source);
         return 1;
-                    })))
+    }
 
-            .then(command("shutdown")
-                .requires(ModRegistry.Permissions.PERMISSION_SHUTDOWN)
-                .argManyValue("computers", manyComputers(), s -> ServerContext.get(s.getServer()).registry().getComputers())
-                .executes((context, computerSelectors) -> {
+    /**
+     * Shutdown a list of computers.
+     *
+     * @param source    The thing that executed this command.
+     * @param computers The computers to shutdown.
+     * @return The constant {@code 1}.
+     */
+    private static int shutdown(CommandSourceStack source, Collection<ServerComputer> computers) {
         var shutdown = 0;
-                    var computers = unwrap(context.getSource(), computerSelectors);
         for (var computer : computers) {
             if (computer.isOn()) shutdown++;
             computer.shutdown();
         }
 
         var didShutdown = shutdown;
-                    context.getSource().sendSuccess(() -> Component.translatable("commands.computercraft.shutdown.done", didShutdown, computers.size()), false);
+        source.sendSuccess(() -> Component.translatable("commands.computercraft.shutdown.done", didShutdown, computers.size()), false);
         return shutdown;
-                }))
+    }
 
-            .then(command("turn-on")
-                .requires(ModRegistry.Permissions.PERMISSION_TURN_ON)
-                .argManyValue("computers", manyComputers(), s -> ServerContext.get(s.getServer()).registry().getComputers())
-                .executes((context, computerSelectors) -> {
+    /**
+     * Turn on a list of computers.
+     *
+     * @param source    The thing that executed this command.
+     * @param computers The computers to turn on.
+     * @return The constant {@code 1}.
+     */
+    private static int turnOn(CommandSourceStack source, Collection<ServerComputer> computers) {
         var on = 0;
-                    var computers = unwrap(context.getSource(), computerSelectors);
         for (var computer : computers) {
             if (!computer.isOn()) on++;
             computer.turnOn();
         }
 
         var didOn = on;
-                    context.getSource().sendSuccess(() -> Component.translatable("commands.computercraft.turn_on.done", didOn, computers.size()), false);
+        source.sendSuccess(() -> Component.translatable("commands.computercraft.turn_on.done", didOn, computers.size()), false);
         return on;
-                }))
-
-            .then(command("tp")
-                .requires(ModRegistry.Permissions.PERMISSION_TP)
-                .arg("computer", oneComputer())
-                .executes(context -> {
-                    var computer = getComputerArgument(context, "computer");
-                    var world = computer.getLevel();
-                    var pos = computer.getPosition();
-
-                    var entity = context.getSource().getEntityOrException();
-                    if (!(entity instanceof ServerPlayer player)) throw TP_NOT_PLAYER.create();
-
-                    if (player.getCommandSenderWorld() == world) {
-                        player.connection.teleport(
-                            pos.getX() + 0.5, pos.getY(), pos.getZ() + 0.5, 0, 0,
-                            EnumSet.noneOf(RelativeMovement.class)
-                        );
-                    } else {
-                        player.teleportTo(world,
-                            pos.getX() + 0.5, pos.getY(), pos.getZ() + 0.5, 0, 0
-                        );
     }
 
-                    return 1;
-                }))
+    /**
+     * Teleport to a computer.
+     *
+     * @param source   The thing that executed this command. This must be an entity, other types will throw an exception.
+     * @param computer The computer to teleport to.
+     * @return The constant {@code 1}.
+     */
+    private static int teleport(CommandSourceStack source, ServerComputer computer) throws CommandSyntaxException {
+        var world = computer.getLevel();
+        var pos = Vec3.atBottomCenterOf(computer.getPosition());
+        source.getEntityOrException().teleportTo(world, pos.x(), pos.y(), pos.z(), EnumSet.noneOf(RelativeMovement.class), 0, 0);
 
-            .then(command("queue")
-                .requires(ModRegistry.Permissions.PERMISSION_QUEUE)
-                .arg(
-                    RequiredArgumentBuilder.<CommandSourceStack, ComputersArgumentType.ComputersSupplier>argument("computer", manyComputers())
-                        .suggests((context, builder) -> Suggestions.empty())
-                )
-                .argManyValue("args", StringArgumentType.string(), Collections.emptyList())
-                .executes((ctx, args) -> {
-                    var computers = getComputersArgument(ctx, "computer");
+        return 1;
+    }
+
+    /**
+     * Queue a {@code computer_command} event on a command computer.
+     *
+     * @param computers The list of computers to queue on.
+     * @param args      The arguments for this event.
+     * @return The number of computers this event was queued on.
+     */
+    private static int queue(Collection<ServerComputer> computers, List<String> args) {
         var rest = args.toArray();
 
         var queued = 0;
@@ -195,14 +245,17 @@ public final class CommandComputerCraft {
         }
 
         return queued;
-                }))
+    }
 
-            .then(command("view")
-                .requires(ModRegistry.Permissions.PERMISSION_VIEW)
-                .arg("computer", oneComputer())
-                .executes(context -> {
-                    var player = context.getSource().getPlayerOrException();
-                    var computer = getComputerArgument(context, "computer");
+    /**
+     * Open a terminal for a computer.
+     *
+     * @param source   The thing that executed this command.
+     * @param computer The computer to view.
+     * @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() {
@@ -215,33 +268,52 @@ public final class CommandComputerCraft {
             }
         });
         return 1;
-                }))
+    }
 
-            .then(choice("track")
-                .requires(ModRegistry.Permissions.PERMISSION_TRACK)
-                .then(command("start")
-                    .executes(context -> {
-                        getMetricsInstance(context.getSource()).start();
+    /**
+     * Start tracking metrics for the current player.
+     *
+     * @param source The thing that executed this command.
+     * @return The constant {@code 1}.
+     */
+    private static int trackStart(CommandSourceStack source) {
+        getMetricsInstance(source).start();
 
         var stopCommand = "/computercraft track stop";
-                        context.getSource().sendSuccess(() -> Component.translatable(
+        source.sendSuccess(() -> Component.translatable(
             "commands.computercraft.track.start.stop",
             link(text(stopCommand), stopCommand, Component.translatable("commands.computercraft.track.stop.action"))
         ), false);
         return 1;
-                    }))
+    }
 
-                .then(command("stop")
-                    .executes(context -> {
-                        var timings = getMetricsInstance(context.getSource());
-                        if (!timings.stop()) throw NOT_TRACKING_EXCEPTION.create();
-                        displayTimings(context.getSource(), timings.getSnapshot(), new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.AVG), DEFAULT_FIELDS);
+    /**
+     * Stop tracking metrics for the current player, displaying a table with the results.
+     *
+     * @param source The thing that executed this command.
+     * @return The constant {@code 1}.
+     */
+    private static int trackStop(CommandSourceStack source) throws CommandSyntaxException {
+        var metrics = getMetricsInstance(source);
+        if (!metrics.stop()) throw NOT_TRACKING_EXCEPTION.create();
+        displayTimings(source, metrics.getSnapshot(), new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.AVG), DEFAULT_FIELDS);
         return 1;
-                    }))
+    }
 
-                .then(command("dump")
-                    .argManyValue("fields", metric(), DEFAULT_FIELDS)
-                    .executes((context, fields) -> {
+    private static final List<AggregatedMetric> DEFAULT_FIELDS = List.of(
+        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.COUNT),
+        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.NONE),
+        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.AVG)
+    );
+
+    /**
+     * Display the latest metrics for the current player.
+     *
+     * @param source The thing that executed this command.
+     * @param fields The fields to display in this table, defaulting to {@link #DEFAULT_FIELDS}.
+     * @return The constant {@code 1}.
+     */
+    private static int trackDump(CommandSourceStack source, List<AggregatedMetric> fields) throws CommandSyntaxException {
         AggregatedMetric sort;
         if (fields.size() == 1 && DEFAULT_FIELDS.contains(fields.get(0))) {
             sort = fields.get(0);
@@ -250,11 +322,11 @@ public final class CommandComputerCraft {
             sort = fields.get(0);
         }
 
-                        return displayTimings(context.getSource(), sort, fields);
-                    })))
-        );
+        return displayTimings(source, getMetricsInstance(source).getTimings(), sort, fields);
     }
 
+    // Additional helper functions.
+
     private static Component linkComputer(CommandSourceStack source, @Nullable ServerComputer serverComputer, int computerId) {
         var out = Component.literal("");
 
@@ -327,16 +399,6 @@ public final class CommandComputerCraft {
         return ServerContext.get(source.getServer()).metrics().getMetricsInstance(entity instanceof Player ? entity.getUUID() : SYSTEM_UUID);
     }
 
-    private static final List<AggregatedMetric> DEFAULT_FIELDS = Arrays.asList(
-        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.COUNT),
-        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.NONE),
-        new AggregatedMetric(Metrics.COMPUTER_TASKS, Aggregate.AVG)
-    );
-
-    private static int displayTimings(CommandSourceStack source, AggregatedMetric sortField, List<AggregatedMetric> fields) throws CommandSyntaxException {
-        return displayTimings(source, getMetricsInstance(source).getTimings(), sortField, fields);
-    }
-
     private static int displayTimings(CommandSourceStack source, List<ComputerMetrics> timings, AggregatedMetric sortField, List<AggregatedMetric> fields) throws CommandSyntaxException {
         if (timings.isEmpty()) throw NO_TIMINGS_EXCEPTION.create();
 

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

@@ -18,9 +18,6 @@ public final class Exceptions {
     static final SimpleCommandExceptionType NOT_TRACKING_EXCEPTION = translated("commands.computercraft.track.stop.not_enabled");
     static final SimpleCommandExceptionType NO_TIMINGS_EXCEPTION = translated("commands.computercraft.track.dump.no_timings");
 
-    static final SimpleCommandExceptionType TP_NOT_THERE = translated("commands.computercraft.tp.not_there");
-    static final SimpleCommandExceptionType TP_NOT_PLAYER = translated("commands.computercraft.tp.not_player");
-
     public static final SimpleCommandExceptionType ARGUMENT_EXPECTED = translated("argument.computercraft.argument_expected");
 
     private static SimpleCommandExceptionType translated(String key) {

projects/common/src/main/java/dan200/computercraft/shared/command/arguments/ComputersArgumentType.java

@@ -32,7 +32,7 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
     private static final ComputersArgumentType MANY = new ComputersArgumentType(false);
     private static final ComputersArgumentType SOME = new ComputersArgumentType(true);
 
-    private static final List<String> EXAMPLES = Arrays.asList(
+    private static final List<String> EXAMPLES = List.of(
         "0", "#0", "@Label", "~Advanced"
     );
 
@@ -75,7 +75,7 @@ public final class ComputersArgumentType implements ArgumentType<ComputersArgume
             var instance = reader.readInt();
             computers = s -> {
                 var computer = ServerContext.get(s.getServer()).registry().get(instance);
-                return computer == null ? Collections.emptyList() : Collections.singletonList(computer);
+                return computer == null ? List.of() : List.of(computer);
             };
         }
 

projects/common/src/main/java/dan200/computercraft/shared/command/builder/CommandBuilder.java

@@ -15,7 +15,6 @@ import net.minecraft.commands.CommandSourceStack;
 
 import javax.annotation.Nullable;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
@@ -63,7 +62,7 @@ public class CommandBuilder<S> implements CommandNodeBuilder<S, Command<S>> {
     }
 
     public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argManyValue(String name, ArgumentType<T> type, T defaultValue) {
-        return argManyValue(name, type, Collections.singletonList(defaultValue));
+        return argManyValue(name, type, List.of(defaultValue));
     }
 
     public <T> CommandNodeBuilder<S, ArgCommand<S, List<T>>> argMany(String name, ArgumentType<T> type, Supplier<List<T>> empty) {

projects/common/src/main/java/dan200/computercraft/shared/computer/apis/CommandAPI.java

@@ -134,12 +134,12 @@ public class CommandAPI implements ILuaAPI {
     public final List<String> list(IArguments args) throws LuaException {
         var server = computer.getLevel().getServer();
 
-        if (server == null) return Collections.emptyList();
+        if (server == null) return List.of();
         CommandNode<CommandSourceStack> node = server.getCommands().getDispatcher().getRoot();
         for (var j = 0; j < args.count(); j++) {
             var name = args.getString(j);
             node = node.getChild(name);
-            if (!(node instanceof LiteralCommandNode)) return Collections.emptyList();
+            if (!(node instanceof LiteralCommandNode)) return List.of();
         }
 
         List<String> result = new ArrayList<>();

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

@@ -0,0 +1,23 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.computer.blocks;
+
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.platform.RegistryEntry;
+import net.minecraft.world.level.block.GameMasterBlock;
+import net.minecraft.world.level.block.entity.BlockEntityType;
+
+/**
+ * A subclass of {@link ComputerBlock} which implements {@link GameMasterBlock}, to prevent players breaking it without
+ * permission.
+ *
+ * @param <T> The type of the computer block entity.
+ * @see dan200.computercraft.shared.computer.items.CommandComputerItem
+ */
+public class CommandComputerBlock<T extends CommandComputerBlockEntity> extends ComputerBlock<T> implements GameMasterBlock {
+    public CommandComputerBlock(Properties settings, ComputerFamily family, RegistryEntry<BlockEntityType<T>> type) {
+        super(settings, family, type);
+    }
+}

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

@@ -104,11 +104,15 @@ public class CommandComputerBlockEntity extends ComputerBlockEntity {
         if (server == null || !server.isCommandBlockEnabled()) {
             player.displayClientMessage(Component.translatable("advMode.notEnabled"), true);
             return false;
-        } else if (Config.commandRequireCreative ? !player.canUseGameMasterBlocks() : !server.getPlayerList().isOp(player.getGameProfile())) {
+        } else if (!canUseCommandBlock(player)) {
             player.displayClientMessage(Component.translatable("advMode.notAllowed"), true);
             return false;
         }
 
         return true;
     }
+
+    private static boolean canUseCommandBlock(Player player) {
+        return Config.commandRequireCreative ? player.canUseGameMasterBlocks() : player.hasPermissions(2);
+    }
 }

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

@@ -4,8 +4,33 @@
 
 package dan200.computercraft.shared.computer.core;
 
-public enum ComputerFamily {
-    NORMAL,
-    ADVANCED,
-    COMMAND
+import com.google.gson.JsonObject;
+import com.google.gson.JsonSyntaxException;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.util.StringRepresentable;
+
+public enum ComputerFamily implements StringRepresentable {
+    NORMAL("normal"),
+    ADVANCED("advanced"),
+    COMMAND("command");
+
+    private final String name;
+
+    ComputerFamily(String name) {
+        this.name = name;
+    }
+
+    public static ComputerFamily getFamily(JsonObject json, String name) {
+        var familyName = GsonHelper.getAsString(json, name);
+        for (var family : values()) {
+            if (family.getSerializedName().equalsIgnoreCase(familyName)) return family;
+        }
+
+        throw new JsonSyntaxException("Unknown computer family '" + familyName + "' for field " + name);
+    }
+
+    @Override
+    public String getSerializedName() {
+        return name;
+    }
 }

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

@@ -21,6 +21,8 @@ import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
+import static dan200.computercraft.core.filesystem.MountHelpers.NO_SUCH_FILE;
+
 /**
  * A mount backed by Minecraft's {@link ResourceManager}.
  *
@@ -29,8 +31,6 @@ import java.util.Map;
 public final class ResourceMount extends ArchiveMount<ResourceMount.FileEntry> {
     private static final Logger LOG = LoggerFactory.getLogger(ResourceMount.class);
 
-    private static final byte[] TEMP_BUFFER = new byte[8192];
-
     /**
      * Maintain a cache of currently loaded resource mounts. This cache is invalidated when currentManager changes.
      */
@@ -60,7 +60,7 @@ public final class ResourceMount extends ArchiveMount<ResourceMount.FileEntry> {
         var hasAny = false;
         String existingNamespace = null;
 
-        var newRoot = new FileEntry("", new ResourceLocation(namespace, subPath));
+        var newRoot = new FileEntry(new ResourceLocation(namespace, subPath));
         for (var file : manager.listResources(subPath, s -> true).keySet()) {
             existingNamespace = file.getNamespace();
 
@@ -68,7 +68,11 @@ public final class ResourceMount extends ArchiveMount<ResourceMount.FileEntry> {
             if (!FileSystem.contains(subPath, file.getPath())) continue; // Some packs seem to include the parent?
 
             var localPath = FileSystem.toLocal(file.getPath(), subPath);
-            create(newRoot, localPath);
+            try {
+                getOrCreateChild(newRoot, localPath, this::createEntry);
+            } catch (ResourceLocationException e) {
+                LOG.warn("Cannot create resource location for {} ({})", localPath, e.getMessage());
+            }
             hasAny = true;
         }
 
@@ -83,65 +87,24 @@ public final class ResourceMount extends ArchiveMount<ResourceMount.FileEntry> {
         }
     }
 
-    private void create(FileEntry lastEntry, String path) {
-        var lastIndex = 0;
-        while (lastIndex < path.length()) {
-            var nextIndex = path.indexOf('/', lastIndex);
-            if (nextIndex < 0) nextIndex = path.length();
-
-            var part = path.substring(lastIndex, nextIndex);
-            if (lastEntry.children == null) lastEntry.children = new HashMap<>();
-
-            var nextEntry = lastEntry.children.get(part);
-            if (nextEntry == null) {
-                ResourceLocation childPath;
-                try {
-                    childPath = new ResourceLocation(namespace, subPath + "/" + path);
-                } catch (ResourceLocationException e) {
-                    LOG.warn("Cannot create resource location for {} ({})", part, e.getMessage());
-                    return;
-                }
-                lastEntry.children.put(part, nextEntry = new FileEntry(path, childPath));
-            }
-
-            lastEntry = nextEntry;
-            lastIndex = nextIndex + 1;
-        }
+    private FileEntry createEntry(String path) {
+        return new FileEntry(new ResourceLocation(namespace, subPath + "/" + path));
     }
 
     @Override
-    public long getSize(FileEntry file) {
+    protected byte[] getFileContents(String path, FileEntry file) throws IOException {
         var resource = manager.getResource(file.identifier).orElse(null);
-        if (resource == null) return 0;
-
-        try (var stream = resource.open()) {
-            int total = 0, read = 0;
-            do {
-                total += read;
-                read = stream.read(TEMP_BUFFER);
-            } while (read > 0);
-
-            return total;
-        } catch (IOException e) {
-            return 0;
-        }
-    }
-
-    @Override
-    public byte[] getContents(FileEntry file) throws IOException {
-        var resource = manager.getResource(file.identifier).orElse(null);
-        if (resource == null) throw new FileOperationException(file.path, NO_SUCH_FILE);
+        if (resource == null) throw new FileOperationException(path, NO_SUCH_FILE);
 
         try (var stream = resource.open()) {
             return stream.readAllBytes();
         }
     }
 
-    protected static class FileEntry extends ArchiveMount.FileEntry<FileEntry> {
+    protected static final class FileEntry extends ArchiveMount.FileEntry<FileEntry> {
         final ResourceLocation identifier;
 
-        FileEntry(String path, ResourceLocation identifier) {
-            super(path);
+        FileEntry(ResourceLocation identifier) {
             this.identifier = identifier;
         }
     }

projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java

@@ -64,13 +64,7 @@ public abstract class AbstractComputerItem extends BlockItem implements ICompute
 
     @Override
     public @Nullable Mount createDataMount(ItemStack stack, ServerLevel level) {
-        var family = getFamily();
-        if (family != ComputerFamily.COMMAND) {
         var id = getComputerID(stack);
-            if (id >= 0) {
-                return ComputerCraftAPI.createSaveDirMount(level.getServer(), "computer/" + id, Config.computerSpaceLimit);
-            }
-        }
-        return null;
+        return id >= 0 ? ComputerCraftAPI.createSaveDirMount(level.getServer(), "computer/" + id, Config.computerSpaceLimit) : null;
     }
 }

projects/common/src/main/java/dan200/computercraft/shared/computer/items/CommandComputerItem.java

@@ -0,0 +1,38 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.computer.items;
+
+import dan200.computercraft.api.filesystem.Mount;
+import dan200.computercraft.shared.computer.blocks.ComputerBlock;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.context.BlockPlaceContext;
+import net.minecraft.world.level.block.state.BlockState;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * A {@link ComputerItem} which prevents players placing it without permission.
+ *
+ * @see net.minecraft.world.item.GameMasterBlockItem
+ * @see dan200.computercraft.shared.computer.blocks.CommandComputerBlock
+ */
+public class CommandComputerItem extends ComputerItem {
+    public CommandComputerItem(ComputerBlock<?> block, Properties settings) {
+        super(block, settings);
+    }
+
+    @Override
+    protected @Nullable BlockState getPlacementState(BlockPlaceContext context) {
+        // Prohibit players placing this block in survival or when not opped.
+        var player = context.getPlayer();
+        return player != null && !player.canUseGameMasterBlocks() ? null : super.getPlacementState(context);
+    }
+
+    @Override
+    public @Nullable Mount createDataMount(ItemStack stack, ServerLevel level) {
+        // Don't allow command computers to be mounted in disk drives.
+        return null;
+    }
+}

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

@@ -4,7 +4,12 @@
 
 package dan200.computercraft.shared.computer.menu;
 
-import dan200.computercraft.shared.computer.upload.*;
+import dan200.computercraft.core.apis.handles.ByteBufferChannel;
+import dan200.computercraft.core.apis.transfer.TransferredFile;
+import dan200.computercraft.core.apis.transfer.TransferredFiles;
+import dan200.computercraft.shared.computer.upload.FileSlice;
+import dan200.computercraft.shared.computer.upload.FileUpload;
+import dan200.computercraft.shared.computer.upload.UploadResult;
 import dan200.computercraft.shared.network.client.UploadResultMessage;
 import dan200.computercraft.shared.platform.PlatformHelper;
 import it.unimi.dsi.fastutil.ints.IntOpenHashSet;
@@ -18,7 +23,6 @@ import org.slf4j.LoggerFactory;
 import javax.annotation.Nullable;
 import java.util.List;
 import java.util.UUID;
-import java.util.stream.Collectors;
 
 /**
  * The default concrete implementation of {@link ServerInputHandler}.
@@ -150,8 +154,14 @@ public class ServerInputState<T extends AbstractContainerMenu & ComputerMenu> im
             }
         }
 
-        computer.queueEvent("file_transfer", new Object[]{
-            new TransferredFiles(player, owner, toUpload.stream().map(x -> new TransferredFile(x.getName(), x.getBytes())).collect(Collectors.toList())),
+        computer.queueEvent(TransferredFiles.EVENT, new Object[]{
+            new TransferredFiles(
+                toUpload.stream().map(x -> new TransferredFile(x.getName(), new ByteBufferChannel(x.getBytes()))).toList(),
+                () -> {
+                    if (player.isAlive() && player.containerMenu == owner) {
+                        PlatformHelper.get().sendToPlayer(UploadResultMessage.consumed(owner), player);
+                    }
+                }),
         });
         return UploadResultMessage.queued(owner);
     }

projects/common/src/main/java/dan200/computercraft/shared/computer/metrics/ComputerMBean.java

@@ -141,7 +141,7 @@ public final class ComputerMBean implements DynamicMBean, ComputerMetricsObserve
         }
     }
 
-    private static class Counter {
+    private static final class Counter {
         final AtomicLong value = new AtomicLong();
         final AtomicLong count = new AtomicLong();
     }

projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerConvertRecipe.java

@@ -5,31 +5,20 @@
 package dan200.computercraft.shared.computer.recipe;
 
 import dan200.computercraft.shared.computer.items.IComputerItem;
-import net.minecraft.core.NonNullList;
+import dan200.computercraft.shared.recipe.CustomShapedRecipe;
+import dan200.computercraft.shared.recipe.ShapedRecipeSpec;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.inventory.CraftingContainer;
 import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.crafting.CraftingBookCategory;
-import net.minecraft.world.item.crafting.Ingredient;
-import net.minecraft.world.item.crafting.ShapedRecipe;
 import net.minecraft.world.level.Level;
 
 /**
- * Represents a recipe which converts a computer from one form into another.
+ * A recipe which converts a computer from one form into another.
  */
-public abstract class ComputerConvertRecipe extends ShapedRecipe {
-    private final String group;
-    private final ItemStack result;
-
-    public ComputerConvertRecipe(ResourceLocation identifier, String group, CraftingBookCategory category, int width, int height, NonNullList<Ingredient> ingredients, ItemStack result) {
-        super(identifier, group, category, width, height, ingredients, result);
-        this.group = group;
-        this.result = result;
-    }
-
-    public ItemStack getResultItem() {
-        return result;
+public abstract class ComputerConvertRecipe extends CustomShapedRecipe {
+    public ComputerConvertRecipe(ResourceLocation identifier, ShapedRecipeSpec recipe) {
+        super(identifier, recipe);
     }
 
     protected abstract ItemStack convert(IComputerItem item, ItemStack stack);
@@ -55,9 +44,4 @@ public abstract class ComputerConvertRecipe extends ShapedRecipe {
 
         return ItemStack.EMPTY;
     }
-
-    @Override
-    public String getGroup() {
-        return group;
-    }
 }

projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerFamilyRecipe.java

@@ -1,72 +0,0 @@
-// SPDX-FileCopyrightText: 2018 The CC: Tweaked Developers
-//
-// SPDX-License-Identifier: MPL-2.0
-
-package dan200.computercraft.shared.computer.recipe;
-
-import com.google.gson.JsonObject;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
-import dan200.computercraft.shared.util.RecipeUtil;
-import net.minecraft.core.NonNullList;
-import net.minecraft.network.FriendlyByteBuf;
-import net.minecraft.resources.ResourceLocation;
-import net.minecraft.util.GsonHelper;
-import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.crafting.CraftingBookCategory;
-import net.minecraft.world.item.crafting.Ingredient;
-import net.minecraft.world.item.crafting.RecipeSerializer;
-
-public abstract class ComputerFamilyRecipe extends ComputerConvertRecipe {
-    private final ComputerFamily family;
-
-    public ComputerFamilyRecipe(ResourceLocation identifier, String group, CraftingBookCategory category, int width, int height, NonNullList<Ingredient> ingredients, ItemStack result, ComputerFamily family) {
-        super(identifier, group, category, width, height, ingredients, result);
-        this.family = family;
-    }
-
-    public ComputerFamily getFamily() {
-        return family;
-    }
-
-    public abstract static class Serializer<T extends ComputerFamilyRecipe> implements RecipeSerializer<T> {
-        protected abstract T create(ResourceLocation identifier, String group, CraftingBookCategory category, int width, int height, NonNullList<Ingredient> ingredients, ItemStack result, ComputerFamily family);
-
-        @Override
-        public T fromJson(ResourceLocation identifier, JsonObject json) {
-            var group = GsonHelper.getAsString(json, "group", "");
-            var category = CraftingBookCategory.CODEC.byName(GsonHelper.getAsString(json, "category", null), CraftingBookCategory.MISC);
-            var family = RecipeUtil.getFamily(json, "family");
-
-            var template = RecipeUtil.getTemplate(json);
-            var result = itemStackFromJson(GsonHelper.getAsJsonObject(json, "result"));
-
-            return create(identifier, group, category, template.width(), template.height(), template.ingredients(), result, family);
-        }
-
-        @Override
-        public T fromNetwork(ResourceLocation identifier, FriendlyByteBuf buf) {
-            var width = buf.readVarInt();
-            var height = buf.readVarInt();
-            var group = buf.readUtf();
-            var category = buf.readEnum(CraftingBookCategory.class);
-
-            var ingredients = NonNullList.withSize(width * height, Ingredient.EMPTY);
-            for (var i = 0; i < ingredients.size(); i++) ingredients.set(i, Ingredient.fromNetwork(buf));
-
-            var result = buf.readItem();
-            var family = buf.readEnum(ComputerFamily.class);
-            return create(identifier, group, category, width, height, ingredients, result, family);
-        }
-
-        @Override
-        public void toNetwork(FriendlyByteBuf buf, T recipe) {
-            buf.writeVarInt(recipe.getWidth());
-            buf.writeVarInt(recipe.getHeight());
-            buf.writeUtf(recipe.getGroup());
-            buf.writeEnum(recipe.category());
-            for (var ingredient : recipe.getIngredients()) ingredient.toNetwork(buf);
-            buf.writeItem(recipe.getResultItem());
-            buf.writeEnum(recipe.getFamily());
-        }
-    }
-}

projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerUpgradeRecipe.java

@@ -4,35 +4,57 @@
 
 package dan200.computercraft.shared.computer.recipe;
 
+import com.google.gson.JsonObject;
 import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.items.IComputerItem;
-import net.minecraft.core.NonNullList;
+import dan200.computercraft.shared.recipe.ShapedRecipeSpec;
+import net.minecraft.network.FriendlyByteBuf;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.crafting.CraftingBookCategory;
-import net.minecraft.world.item.crafting.Ingredient;
 import net.minecraft.world.item.crafting.RecipeSerializer;
 
-public final class ComputerUpgradeRecipe extends ComputerFamilyRecipe {
-    private ComputerUpgradeRecipe(ResourceLocation identifier, String group, CraftingBookCategory category, int width, int height, NonNullList<Ingredient> ingredients, ItemStack result, ComputerFamily family) {
-        super(identifier, group, category, width, height, ingredients, result, family);
+/**
+ * A recipe which "upgrades" a {@linkplain IComputerItem computer}, converting it from one {@linkplain ComputerFamily
+ * family} to another.
+ */
+public final class ComputerUpgradeRecipe extends ComputerConvertRecipe {
+    private final ComputerFamily family;
+
+    private ComputerUpgradeRecipe(ResourceLocation identifier, ShapedRecipeSpec recipe, ComputerFamily family) {
+        super(identifier, recipe);
+        this.family = family;
     }
 
     @Override
     protected ItemStack convert(IComputerItem item, ItemStack stack) {
-        return item.withFamily(stack, getFamily());
+        return item.withFamily(stack, family);
     }
 
     @Override
-    public RecipeSerializer<?> getSerializer() {
+    public RecipeSerializer<ComputerUpgradeRecipe> getSerializer() {
         return ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get();
     }
 
-    public static class Serializer extends ComputerFamilyRecipe.Serializer<ComputerUpgradeRecipe> {
+    public static class Serializer implements RecipeSerializer<ComputerUpgradeRecipe> {
         @Override
-        protected ComputerUpgradeRecipe create(ResourceLocation identifier, String group, CraftingBookCategory category, int width, int height, NonNullList<Ingredient> ingredients, ItemStack result, ComputerFamily family) {
-            return new ComputerUpgradeRecipe(identifier, group, category, width, height, ingredients, result, family);
+        public ComputerUpgradeRecipe fromJson(ResourceLocation identifier, JsonObject json) {
+            var recipe = ShapedRecipeSpec.fromJson(json);
+            var family = ComputerFamily.getFamily(json, "family");
+            return new ComputerUpgradeRecipe(identifier, recipe, family);
+        }
+
+        @Override
+        public ComputerUpgradeRecipe fromNetwork(ResourceLocation identifier, FriendlyByteBuf buf) {
+            var recipe = ShapedRecipeSpec.fromNetwork(buf);
+            var family = buf.readEnum(ComputerFamily.class);
+            return new ComputerUpgradeRecipe(identifier, recipe, family);
+        }
+
+        @Override
+        public void toNetwork(FriendlyByteBuf buf, ComputerUpgradeRecipe recipe) {
+            recipe.toSpec().toNetwork(buf);
+            buf.writeEnum(recipe.family);
         }
     }
 }

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

@@ -30,7 +30,6 @@ public final class ConfigSpec {
     public static final ConfigFile.Value<Integer> computerSpaceLimit;
     public static final ConfigFile.Value<Integer> floppySpaceLimit;
     public static final ConfigFile.Value<Integer> maximumFilesOpen;
-    public static final ConfigFile.Value<Boolean> disableLua51Features;
     public static final ConfigFile.Value<String> defaultComputerSettings;
     public static final ConfigFile.Value<Boolean> logComputerErrors;
     public static final ConfigFile.Value<Boolean> commandRequireCreative;
@@ -115,12 +114,6 @@ public final class ConfigSpec {
                 .comment("Set how many files a computer can have open at the same time. Set to 0 for unlimited.")
                 .defineInRange("maximum_open_files", CoreConfig.maximumFilesOpen, 0, Integer.MAX_VALUE);
 
-            disableLua51Features = builder
-                .comment("""
-                    Set this to true to disable Lua 5.1 functions that will be removed in a future
-                    update. Useful for ensuring forward compatibility of your programs now.""")
-                .define("disable_lua51_features", CoreConfig.disableLua51Features);
-
             defaultComputerSettings = builder
                 .comment("""
                     A comma separated list of default system settings to set on new computers.
@@ -395,7 +388,6 @@ public final class ConfigSpec {
         Config.floppySpaceLimit = floppySpaceLimit.get();
         Config.uploadMaxSize = uploadMaxSize.get();
         CoreConfig.maximumFilesOpen = maximumFilesOpen.get();
-        CoreConfig.disableLua51Features = disableLua51Features.get();
         CoreConfig.defaultComputerSettings = defaultComputerSettings.get();
         Config.commandRequireCreative = commandRequireCreative.get();
 

projects/common/src/main/java/dan200/computercraft/shared/data/BlockNamedEntityLootCondition.java

@@ -12,7 +12,6 @@ import net.minecraft.world.level.storage.loot.parameters.LootContextParams;
 import net.minecraft.world.level.storage.loot.predicates.LootItemCondition;
 import net.minecraft.world.level.storage.loot.predicates.LootItemConditionType;
 
-import java.util.Collections;
 import java.util.Set;
 
 /**
@@ -33,7 +32,7 @@ public final class BlockNamedEntityLootCondition implements LootItemCondition {
 
     @Override
     public Set<LootContextParam<?>> getReferencedContextParams() {
-        return Collections.singleton(LootContextParams.BLOCK_ENTITY);
+        return Set.of(LootContextParams.BLOCK_ENTITY);
     }
 
     @Override

projects/common/src/main/java/dan200/computercraft/shared/data/HasComputerIdLootCondition.java

@@ -12,7 +12,6 @@ import net.minecraft.world.level.storage.loot.parameters.LootContextParams;
 import net.minecraft.world.level.storage.loot.predicates.LootItemCondition;
 import net.minecraft.world.level.storage.loot.predicates.LootItemConditionType;
 
-import java.util.Collections;
 import java.util.Set;
 
 /**
@@ -33,7 +32,7 @@ public final class HasComputerIdLootCondition implements LootItemCondition {
 
     @Override
     public Set<LootContextParam<?>> getReferencedContextParams() {
-        return Collections.singleton(LootContextParams.BLOCK_ENTITY);
+        return Set.of(LootContextParams.BLOCK_ENTITY);
     }
 
     @Override

projects/common/src/main/java/dan200/computercraft/shared/data/PlayerCreativeLootCondition.java

@@ -12,7 +12,6 @@ import net.minecraft.world.level.storage.loot.parameters.LootContextParams;
 import net.minecraft.world.level.storage.loot.predicates.LootItemCondition;
 import net.minecraft.world.level.storage.loot.predicates.LootItemConditionType;
 
-import java.util.Collections;
 import java.util.Set;
 
 /**
@@ -33,7 +32,7 @@ public final class PlayerCreativeLootCondition implements LootItemCondition {
 
     @Override
     public Set<LootContextParam<?>> getReferencedContextParams() {
-        return Collections.singleton(LootContextParams.THIS_ENTITY);
+        return Set.of(LootContextParams.THIS_ENTITY);
     }
 
     @Override

projects/common/src/main/java/dan200/computercraft/shared/details/ItemDetails.java

@@ -61,7 +61,7 @@ public class ItemDetails {
 
         /*
          * Used to hide some data from ItemStack tooltip.
-         * @see https://minecraft.gamepedia.com/Tutorials/Command_NBT_tags
+         * @see https://minecraft.wiki/w/Tutorials/Command_NBT_tags
          * @see ItemStack#getTooltip
          */
         var hideFlags = tag != null ? tag.getInt("HideFlags") : 0;
@@ -116,6 +116,7 @@ public class ItemDetails {
      * @param enchants    The enchantment map to add it to.
      * @see EnchantmentHelper
      */
+    @SuppressWarnings("NonApiType")
     private static void addEnchantments(ListTag rawEnchants, ArrayList<Map<String, Object>> enchants) {
         if (rawEnchants.isEmpty()) return;
 

projects/common/src/main/java/dan200/computercraft/shared/integration/PermissionRegistry.java

@@ -69,7 +69,7 @@ public abstract class PermissionRegistry {
             .orElseGet(DefaultPermissionRegistry::new);
     }
 
-    private static class DefaultPermissionRegistry extends PermissionRegistry {
+    private static final class DefaultPermissionRegistry extends PermissionRegistry {
         @Override
         public Predicate<CommandSourceStack> registerCommand(String command, UserLevel fallback) {
             checkNotFrozen();

projects/common/src/main/java/dan200/computercraft/shared/integration/RecipeModHelpers.java

@@ -9,14 +9,12 @@ import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.impl.PocketUpgrades;
 import dan200.computercraft.impl.TurtleUpgrades;
 import dan200.computercraft.shared.ModRegistry;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.pocket.items.PocketComputerItem;
 import dan200.computercraft.shared.turtle.items.TurtleItem;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 import java.util.function.Supplier;
 
@@ -24,7 +22,6 @@ import java.util.function.Supplier;
  * Utilities for recipe mod plugins (such as JEI).
  */
 public final class RecipeModHelpers {
-    static final List<ComputerFamily> MAIN_FAMILIES = Arrays.asList(ComputerFamily.NORMAL, ComputerFamily.ADVANCED);
     static final List<Supplier<TurtleItem>> TURTLES = List.of(ModRegistry.Items.TURTLE_NORMAL, ModRegistry.Items.TURTLE_ADVANCED);
     static final List<Supplier<PocketComputerItem>> POCKET_COMPUTERS = List.of(ModRegistry.Items.POCKET_COMPUTER_NORMAL, ModRegistry.Items.POCKET_COMPUTER_ADVANCED);
 

projects/common/src/main/java/dan200/computercraft/shared/integration/UpgradeRecipeGenerator.java

@@ -114,7 +114,7 @@ public class UpgradeRecipeGenerator<T> {
             // Suggest possible upgrades which can be applied to this turtle
             var left = item.getUpgradeWithData(stack, TurtleSide.LEFT);
             var right = item.getUpgradeWithData(stack, TurtleSide.RIGHT);
-            if (left != null && right != null) return Collections.emptyList();
+            if (left != null && right != null) return List.of();
 
             List<T> recipes = new ArrayList<>();
             var ingredient = Ingredient.of(stack);
@@ -135,7 +135,7 @@ public class UpgradeRecipeGenerator<T> {
         } else if (stack.getItem() instanceof PocketComputerItem) {
             // Suggest possible upgrades which can be applied to this turtle
             var back = PocketComputerItem.getUpgrade(stack);
-            if (back != null) return Collections.emptyList();
+            if (back != null) return List.of();
 
             List<T> recipes = new ArrayList<>();
             var ingredient = Ingredient.of(stack);
@@ -148,7 +148,7 @@ public class UpgradeRecipeGenerator<T> {
         } else {
             // If this item is usable as an upgrade, find all possible recipes.
             var upgrades = upgradeItemLookup.get(stack.getItem());
-            if (upgrades == null) return Collections.emptyList();
+            if (upgrades == null) return List.of();
 
             List<T> recipes = null;
             var multiple = false;
@@ -169,7 +169,7 @@ public class UpgradeRecipeGenerator<T> {
                 }
             }
 
-            return recipes == null ? Collections.emptyList() : Collections.unmodifiableList(recipes);
+            return recipes == null ? List.of() : Collections.unmodifiableList(recipes);
         }
     }
 
@@ -215,7 +215,7 @@ public class UpgradeRecipeGenerator<T> {
 
             return Collections.unmodifiableList(recipes);
         } else {
-            return Collections.emptyList();
+            return List.of();
         }
     }
 

projects/common/src/main/java/dan200/computercraft/shared/integration/jei/JEIComputerCraft.java

@@ -22,7 +22,7 @@ import mezz.jei.api.runtime.IJeiRuntime;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.ItemStack;
 
-import java.util.Collections;
+import java.util.List;
 
 @JeiPlugin
 public class JEIComputerCraft implements IModPlugin {
@@ -61,7 +61,7 @@ public class JEIComputerCraft implements IModPlugin {
         var category = registry.createRecipeLookup(RecipeTypes.CRAFTING);
         category.get().forEach(wrapper -> {
             if (RecipeModHelpers.shouldRemoveRecipe(wrapper.getId())) {
-                registry.hideRecipes(RecipeTypes.CRAFTING, Collections.singleton(wrapper));
+                registry.hideRecipes(RecipeTypes.CRAFTING, List.of(wrapper));
             }
         });
     }

projects/common/src/main/java/dan200/computercraft/shared/integration/jei/RecipeResolver.java

@@ -15,7 +15,6 @@ import mezz.jei.api.recipe.category.IRecipeCategory;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.crafting.CraftingRecipe;
 
-import java.util.Collections;
 import java.util.List;
 
 class RecipeResolver implements IRecipeManagerPlugin {
@@ -24,36 +23,36 @@ class RecipeResolver implements IRecipeManagerPlugin {
     @Override
     public <V> List<RecipeType<?>> getRecipeTypes(IFocus<V> focus) {
         var value = focus.getTypedValue().getIngredient();
-        if (!(value instanceof ItemStack stack)) return Collections.emptyList();
+        if (!(value instanceof ItemStack stack)) return List.of();
 
         return switch (focus.getRole()) {
             case INPUT ->
                 stack.getItem() instanceof TurtleItem || stack.getItem() instanceof PocketComputerItem || resolver.isUpgrade(stack)
-                    ? Collections.singletonList(RecipeTypes.CRAFTING)
-                    : Collections.emptyList();
+                    ? List.of(RecipeTypes.CRAFTING)
+                    : List.of();
             case OUTPUT -> stack.getItem() instanceof TurtleItem || stack.getItem() instanceof PocketComputerItem
-                ? Collections.singletonList(RecipeTypes.CRAFTING)
-                : Collections.emptyList();
-            default -> Collections.emptyList();
+                ? List.of(RecipeTypes.CRAFTING)
+                : List.of();
+            default -> List.of();
         };
     }
 
     @Override
     public <T, V> List<T> getRecipes(IRecipeCategory<T> recipeCategory, IFocus<V> focus) {
         if (!(focus.getTypedValue().getIngredient() instanceof ItemStack stack) || recipeCategory.getRecipeType() != RecipeTypes.CRAFTING) {
-            return Collections.emptyList();
+            return List.of();
         }
 
         return switch (focus.getRole()) {
             case INPUT -> cast(resolver.findRecipesWithInput(stack));
             case OUTPUT -> cast(resolver.findRecipesWithOutput(stack));
-            default -> Collections.emptyList();
+            default -> List.of();
         };
     }
 
     @Override
     public <T> List<T> getRecipes(IRecipeCategory<T> recipeCategory) {
-        return Collections.emptyList();
+        return List.of();
     }
 
     @SuppressWarnings({ "unchecked", "rawtypes" })

projects/common/src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDriveBlockEntity.java

@@ -35,7 +35,7 @@ import java.util.concurrent.atomic.AtomicReference;
 public final class DiskDriveBlockEntity extends AbstractContainerBlockEntity {
     private static final String NBT_ITEM = "Item";
 
-    private static class MountInfo {
+    private static final class MountInfo {
         @Nullable
         String mountPath;
     }

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/ComponentLookup.java

@@ -0,0 +1,36 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.peripheral.generic;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+
+import javax.annotation.Nullable;
+
+/**
+ * Extract some component (for instance a capability on Forge, or a {@code BlockApiLookup} on Fabric) from a block and
+ * block entity.
+ *
+ * @param <C> A platform-specific type, used for the invalidation callback.
+ */
+public interface ComponentLookup<C extends Runnable> {
+    /**
+     * Extract some component from a block in the world.
+     *
+     * @param level       The current level.
+     * @param pos         The position of the block in the level.
+     * @param state       The block state at that position.
+     * @param blockEntity The block entity at that position.
+     * @param side        The side of the block to extract the component from. Implementations should try to use a
+     *                    sideless lookup first, but may fall back to a sided lookup if needed.
+     * @param invalidate  An invalidation function to call if this component changes.
+     * @return The found component, or {@code null} if not present.
+     */
+    @Nullable
+    Object find(Level level, BlockPos pos, BlockState state, BlockEntity blockEntity, Direction side, C invalidate);
+}

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralBuilder.java

@@ -6,12 +6,9 @@ package dan200.computercraft.shared.peripheral.generic;
 
 import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.PeripheralType;
-import dan200.computercraft.core.methods.MethodSupplier;
 import dan200.computercraft.core.methods.NamedMethod;
 import dan200.computercraft.core.methods.PeripheralMethod;
-import dan200.computercraft.shared.computer.core.ServerContext;
 import net.minecraft.core.Direction;
-import net.minecraft.server.MinecraftServer;
 import net.minecraft.world.level.block.entity.BlockEntity;
 
 import javax.annotation.Nullable;
@@ -28,16 +25,10 @@ import java.util.Set;
  * See the platform-specific peripheral providers for the usage of this.
  */
 final class GenericPeripheralBuilder {
-    private final MethodSupplier<PeripheralMethod> peripheralMethods;
-
     private @Nullable String name;
     private final Set<String> additionalTypes = new HashSet<>(0);
     private final ArrayList<SaturatedMethod> methods = new ArrayList<>();
 
-    GenericPeripheralBuilder(MinecraftServer server) {
-        peripheralMethods = ServerContext.get(server).peripheralMethods();
-    }
-
     @Nullable
     IPeripheral toPeripheral(BlockEntity blockEntity, Direction side) {
         if (methods.isEmpty()) return null;
@@ -46,8 +37,7 @@ final class GenericPeripheralBuilder {
         return new GenericPeripheral(blockEntity, side, name, additionalTypes, methods);
     }
 
-    boolean addMethods(Object target) {
-        return peripheralMethods.forEachSelfMethod(target, (name, method, info) -> {
+    void addMethod(Object target, String name, PeripheralMethod method, @Nullable NamedMethod<PeripheralMethod> info) {
         methods.add(new SaturatedMethod(target, name, method));
 
         // If we have a peripheral type, use it. Always pick the smallest one, so it's consistent (assuming mods
@@ -58,6 +48,5 @@ final class GenericPeripheralBuilder {
             if (this.name == null || this.name.compareTo(primaryType) > 0) this.name = primaryType;
         }
         if (type != null) additionalTypes.addAll(type.getAdditionalTypes());
-        });
     }
 }

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheralProvider.java

@@ -0,0 +1,69 @@
+// SPDX-FileCopyrightText: 2020 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.peripheral.generic;
+
+import dan200.computercraft.api.lua.GenericSource;
+import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.core.methods.MethodSupplier;
+import dan200.computercraft.core.methods.PeripheralMethod;
+import dan200.computercraft.shared.computer.core.ServerContext;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.annotation.Nullable;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A peripheral provider which finds methods from various {@linkplain GenericSource generic sources}.
+ * <p>
+ * Methods are found using the original block entity itself and a registered list of {@link ComponentLookup}s.
+ *
+ * @param <C> A platform-specific type, used for the invalidation callback.
+ */
+public final class GenericPeripheralProvider<C extends Runnable> {
+    private static final Logger LOG = LoggerFactory.getLogger(GenericPeripheralProvider.class);
+
+    private final List<ComponentLookup<? super C>> lookups = new ArrayList<>();
+
+    /**
+     * Register a component lookup function.
+     *
+     * @param lookup The component lookup function.
+     */
+    public synchronized void registerLookup(ComponentLookup<? super C> lookup) {
+        Objects.requireNonNull(lookup);
+        if (!lookups.contains(lookup)) lookups.add(lookup);
+    }
+
+    public void forEachMethod(MethodSupplier<PeripheralMethod> methods, Level level, BlockPos pos, Direction side, BlockEntity blockEntity, C invalidate, MethodSupplier.TargetedConsumer<PeripheralMethod> consumer) {
+        methods.forEachMethod(blockEntity, consumer);
+
+        for (var lookup : lookups) {
+            var contents = lookup.find(level, pos, blockEntity.getBlockState(), blockEntity, side, invalidate);
+            if (contents != null) methods.forEachMethod(contents, consumer);
+        }
+    }
+
+    @Nullable
+    public IPeripheral getPeripheral(Level level, BlockPos pos, Direction side, @Nullable BlockEntity blockEntity, C invalidate) {
+        if (blockEntity == null) return null;
+
+        var server = level.getServer();
+        if (server == null) {
+            LOG.warn("Fetching peripherals on a non-server level {}.", level, new IllegalStateException("Fetching peripherals on a non-server level."));
+            return null;
+        }
+
+        var builder = new GenericPeripheralBuilder();
+        forEachMethod(ServerContext.get(server).peripheralMethods(), level, pos, side, blockEntity, invalidate, builder::addMethod);
+        return builder.toPeripheral(blockEntity, side);
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlock.java

@@ -4,12 +4,12 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
-import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.annotations.ForgeOverride;
 import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.platform.PlatformHelper;
 import dan200.computercraft.shared.util.WaterloggableHelpers;
 import dan200.computercraft.shared.util.WorldUtil;
+import net.minecraft.Util;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.server.level.ServerLevel;
@@ -52,12 +52,14 @@ public class CableBlock extends Block implements SimpleWaterloggedBlock, EntityB
     public static final BooleanProperty UP = BooleanProperty.create("up");
     public static final BooleanProperty DOWN = BooleanProperty.create("down");
 
-    static final EnumMap<Direction, BooleanProperty> CONNECTIONS =
-        new EnumMap<>(new ImmutableMap.Builder<Direction, BooleanProperty>()
-            .put(Direction.DOWN, DOWN).put(Direction.UP, UP)
-            .put(Direction.NORTH, NORTH).put(Direction.SOUTH, SOUTH)
-            .put(Direction.WEST, WEST).put(Direction.EAST, EAST)
-            .build());
+    static final EnumMap<Direction, BooleanProperty> CONNECTIONS = Util.make(new EnumMap<>(Direction.class), m -> {
+        m.put(Direction.DOWN, DOWN);
+        m.put(Direction.UP, UP);
+        m.put(Direction.NORTH, NORTH);
+        m.put(Direction.SOUTH, SOUTH);
+        m.put(Direction.WEST, WEST);
+        m.put(Direction.EAST, EAST);
+    });
 
     public CableBlock(Properties settings) {
         super(settings);

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableBlockEntity.java

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
-import com.google.common.base.Objects;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
 import dan200.computercraft.api.peripheral.IPeripheral;
@@ -31,12 +30,13 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.Vec3;
 
 import javax.annotation.Nullable;
-import java.util.Collections;
+import java.util.Map;
+import java.util.Objects;
 
 public class CableBlockEntity extends BlockEntity {
     private static final String NBT_PERIPHERAL_ENABLED = "PeripheralAccess";
 
-    private class CableElement extends WiredModemElement {
+    private final class CableElement extends WiredModemElement {
         @Override
         public Level getLevel() {
             return CableBlockEntity.this.getLevel();
@@ -181,7 +181,7 @@ public class CableBlockEntity extends BlockEntity {
         var oldName = peripheral.getConnectedName();
         togglePeripheralAccess();
         var newName = peripheral.getConnectedName();
-        if (!Objects.equal(newName, oldName)) {
+        if (!Objects.equals(newName, oldName)) {
             if (oldName != null) {
                 player.displayClientMessage(Component.translatable("chat.computercraft.wired_modem.peripheral_disconnected",
                     ChatHelpers.copy(oldName)), false);
@@ -274,7 +274,7 @@ public class CableBlockEntity extends BlockEntity {
         if (!canAttachPeripheral() && peripheralAccessAllowed) {
             peripheralAccessAllowed = false;
             peripheral.detach();
-            node.updatePeripherals(Collections.emptyMap());
+            node.updatePeripherals(Map.of());
             setChanged();
             updateBlockState();
         }
@@ -291,7 +291,7 @@ public class CableBlockEntity extends BlockEntity {
             peripheral.detach();
 
             peripheralAccessAllowed = false;
-            node.updatePeripherals(Collections.emptyMap());
+            node.updatePeripherals(Map.of());
         }
 
         updateBlockState();

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/CableShapes.java

@@ -4,9 +4,9 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
-import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.shared.peripheral.modem.ModemShapes;
 import dan200.computercraft.shared.util.DirectionUtil;
+import net.minecraft.Util;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.phys.shapes.Shapes;
@@ -21,16 +21,14 @@ public final class CableShapes {
     private static final double MAX = 1 - MIN;
 
     private static final VoxelShape SHAPE_CABLE_CORE = Shapes.box(MIN, MIN, MIN, MAX, MAX, MAX);
-    private static final EnumMap<Direction, VoxelShape> SHAPE_CABLE_ARM =
-        new EnumMap<>(new ImmutableMap.Builder<Direction, VoxelShape>()
-            .put(Direction.DOWN, Shapes.box(MIN, 0, MIN, MAX, MIN, MAX))
-            .put(Direction.UP, Shapes.box(MIN, MAX, MIN, MAX, 1, MAX))
-            .put(Direction.NORTH, Shapes.box(MIN, MIN, 0, MAX, MAX, MIN))
-            .put(Direction.SOUTH, Shapes.box(MIN, MIN, MAX, MAX, MAX, 1))
-            .put(Direction.WEST, Shapes.box(0, MIN, MIN, MIN, MAX, MAX))
-            .put(Direction.EAST, Shapes.box(MAX, MIN, MIN, 1, MAX, MAX))
-            .build()
-        );
+    private static final EnumMap<Direction, VoxelShape> SHAPE_CABLE_ARM = Util.make(new EnumMap<>(Direction.class), m -> {
+        m.put(Direction.DOWN, Shapes.box(MIN, 0, MIN, MAX, MIN, MAX));
+        m.put(Direction.UP, Shapes.box(MIN, MAX, MIN, MAX, 1, MAX));
+        m.put(Direction.NORTH, Shapes.box(MIN, MIN, 0, MAX, MAX, MIN));
+        m.put(Direction.SOUTH, Shapes.box(MIN, MIN, MAX, MAX, MAX, 1));
+        m.put(Direction.WEST, Shapes.box(0, MIN, MIN, MIN, MAX, MAX));
+        m.put(Direction.EAST, Shapes.box(MAX, MIN, MIN, 1, MAX, MAX));
+    });
 
     private static final VoxelShape[] SHAPES = new VoxelShape[(1 << 6) * 7];
     private static final VoxelShape[] CABLE_SHAPES = new VoxelShape[1 << 6];

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemFullBlockEntity.java

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
-import com.google.common.base.Objects;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
 import dan200.computercraft.api.peripheral.IPeripheral;
@@ -133,7 +132,7 @@ public class WiredModemFullBlockEntity extends BlockEntity {
         togglePeripheralAccess();
         var periphNames = getConnectedPeripheralNames();
 
-        if (!Objects.equal(periphNames, oldPeriphNames)) {
+        if (!Objects.equals(periphNames, oldPeriphNames)) {
             sendPeripheralChanges(player, "chat.computercraft.wired_modem.peripheral_disconnected", oldPeriphNames);
             sendPeripheralChanges(player, "chat.computercraft.wired_modem.peripheral_connected", periphNames);
         }
@@ -241,14 +240,14 @@ public class WiredModemFullBlockEntity extends BlockEntity {
             peripheralAccessAllowed = false;
 
             for (var peripheral : peripherals) peripheral.detach();
-            node.updatePeripherals(Collections.emptyMap());
+            node.updatePeripherals(Map.of());
         }
 
         updateBlockState();
     }
 
     private Set<String> getConnectedPeripheralNames() {
-        if (!peripheralAccessAllowed) return Collections.emptySet();
+        if (!peripheralAccessAllowed) return Set.of();
 
         Set<String> peripherals = new HashSet<>(6);
         for (var peripheral : this.peripherals) {
@@ -259,7 +258,7 @@ public class WiredModemFullBlockEntity extends BlockEntity {
     }
 
     private Map<String, IPeripheral> getConnectedPeripherals() {
-        if (!peripheralAccessAllowed) return Collections.emptyMap();
+        if (!peripheralAccessAllowed) return Map.of();
 
         Map<String, IPeripheral> peripherals = new HashMap<>(6);
         for (var peripheral : this.peripherals) peripheral.extendMap(peripherals);

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemLocalPeripheral.java

@@ -4,8 +4,8 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
+import dan200.computercraft.api.ComputerCraftTags;
 import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.computer.core.ServerContext;
 import dan200.computercraft.shared.platform.ComponentAccess;
 import dan200.computercraft.shared.platform.PlatformHelper;
@@ -103,7 +103,7 @@ public final class WiredModemLocalPeripheral {
 
     public Map<String, IPeripheral> toMap() {
         return peripheral == null
-            ? Collections.emptyMap()
+            ? Map.of()
             : Collections.singletonMap(type + "_" + id, peripheral);
     }
 
@@ -124,8 +124,7 @@ public final class WiredModemLocalPeripheral {
     private IPeripheral getPeripheralFrom(Level world, BlockPos pos, Direction direction) {
         var offset = pos.relative(direction);
 
-        var block = world.getBlockState(offset).getBlock();
-        if (block == ModRegistry.Blocks.WIRED_MODEM_FULL.get() || block == ModRegistry.Blocks.CABLE.get()) return null;
+        if (world.getBlockState(offset).is(ComputerCraftTags.Blocks.PERIPHERAL_HUB_IGNORE)) return null;
 
         var peripheral = peripherals.get((ServerLevel) world, pos, direction);
         return peripheral instanceof WiredModemPeripheral ? null : peripheral;

projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemPeripheral.java

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.peripheral.modem.wired;
 
-import com.google.common.collect.ImmutableMap;
 import dan200.computercraft.api.filesystem.Mount;
 import dan200.computercraft.api.filesystem.WritableMount;
 import dan200.computercraft.api.lua.*;
@@ -69,7 +68,7 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
 
     @Override
     public Set<String> getAdditionalTypes() {
-        return Collections.singleton("peripheral_hub");
+        return Set.of("peripheral_hub");
     }
 
     //region Peripheral methods
@@ -89,7 +88,7 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
     @LuaFunction
     public final Collection<String> getNamesRemote(IComputerAccess computer) {
         var wrappers = getWrappers(computer);
-        return wrappers == null ? Collections.emptySet() : wrappers.keySet();
+        return wrappers == null ? Set.of() : wrappers.keySet();
     }
 
     /**
@@ -429,7 +428,7 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
         public Map<String, IPeripheral> getAvailablePeripherals() {
             if (!attached) throw new NotAttachedException();
             synchronized (element.getRemotePeripherals()) {
-                return ImmutableMap.copyOf(element.getRemotePeripherals());
+                return Map.copyOf(element.getRemotePeripherals());
             }
         }
 

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

@@ -157,7 +157,6 @@ public class MonitorBlockEntity extends BlockEntity {
         if (xIndex == 0 && yIndex == 0) {
             // If we're the origin, set up the new monitor
             serverMonitor = new ServerMonitor(advanced, this);
-            serverMonitor.rebuild();
 
             // And propagate it to child monitors
             for (var x = 0; x < width; x++) {
@@ -178,6 +177,11 @@ public class MonitorBlockEntity extends BlockEntity {
         }
     }
 
+    private void createServerTerminal() {
+        var monitor = createServerMonitor();
+        if (monitor != null && monitor.getTerminal() == null) monitor.rebuild();
+    }
+
     @Nullable
     public ClientMonitor getClientMonitor() {
         if (clientMonitor != null) return clientMonitor;
@@ -349,13 +353,15 @@ public class MonitorBlockEntity extends BlockEntity {
         // Either delete the current monitor or sync a new one.
         if (needsTerminal) {
             if (serverMonitor == null) serverMonitor = new ServerMonitor(advanced, this);
-        } else {
-            serverMonitor = null;
-        }
 
             // Update the terminal's width and height and rebuild it. This ensures the monitor
             // is consistent when syncing it to other monitors.
-        if (serverMonitor != null) serverMonitor.rebuild();
+            serverMonitor.rebuild();
+        } else {
+            // Remove the terminal from the serverMonitor, but keep it around - this ensures that we sync
+            // the (now blank) monitor to the client.
+            if (serverMonitor != null) serverMonitor.reset();
+        }
 
         // Update the other monitors, setting coordinates, dimensions and the server terminal
         var pos = getBlockPos();
@@ -375,6 +381,8 @@ public class MonitorBlockEntity extends BlockEntity {
                 BlockEntityHelpers.updateBlock(monitor);
             }
         }
+
+        assertInvariant();
     }
 
     void updateNeighborsDeferred() {
@@ -485,9 +493,10 @@ public class MonitorBlockEntity extends BlockEntity {
     }
 
     public IPeripheral peripheral() {
-        createServerMonitor();
-        if (peripheral != null) return peripheral;
-        return peripheral = new MonitorPeripheral(this);
+        createServerTerminal();
+        var peripheral = this.peripheral != null ? this.peripheral : (this.peripheral = new MonitorPeripheral(this));
+        assertInvariant();
+        return peripheral;
     }
 
     void addComputer(IComputerAccess computer) {
@@ -526,4 +535,85 @@ public class MonitorBlockEntity extends BlockEntity {
             Math.max(startPos.getZ(), endPos.getZ()) + 1
         );
     }
+
+    /**
+     * Assert all {@linkplain #checkInvariants() monitor invariants} hold.
+     */
+    private void assertInvariant() {
+        assert checkInvariants() : "Monitor invariants failed. See logs.";
+    }
+
+    /**
+     * Check various invariants about this monitor multiblock. This is only called when assertions are enabled, so
+     * will be skipped outside of tests.
+     *
+     * @return Whether all invariants passed.
+     */
+    private boolean checkInvariants() {
+        LOG.debug("Checking monitor invariants at {}", getBlockPos());
+
+        var okay = true;
+
+        if (width <= 0 || height <= 0) {
+            okay = false;
+            LOG.error("Monitor {} has non-positive of {}x{}", getBlockPos(), width, height);
+        }
+
+        var hasPeripheral = false;
+        var origin = getOrigin().getMonitor();
+        var serverMonitor = origin != null ? origin.serverMonitor : this.serverMonitor;
+        for (var x = 0; x < width; x++) {
+            for (var y = 0; y < height; y++) {
+                var monitor = getLoadedMonitor(x, y).getMonitor();
+                if (monitor == null) continue;
+
+                hasPeripheral |= monitor.peripheral != null;
+
+                if (monitor.serverMonitor != null && monitor.serverMonitor != serverMonitor) {
+                    okay = false;
+                    LOG.error(
+                        "Monitor {} expected to be have serverMonitor={}, but was {}",
+                        monitor.getBlockPos(), serverMonitor, monitor.serverMonitor
+                    );
+                }
+
+                if (monitor.xIndex != x || monitor.yIndex != y) {
+                    okay = false;
+                    LOG.error(
+                        "Monitor {} expected to be at {},{}, but believes it is {},{}",
+                        monitor.getBlockPos(), x, y, monitor.xIndex, monitor.yIndex
+                    );
+                }
+
+                if (monitor.width != width || monitor.height != height) {
+                    okay = false;
+                    LOG.error(
+                        "Monitor {} expected to be size {},{}, but believes it is {},{}",
+                        monitor.getBlockPos(), width, height, monitor.width, monitor.height
+                    );
+                }
+
+                var expectedState = getBlockState().setValue(MonitorBlock.STATE, MonitorEdgeState.fromConnections(
+                    y < height - 1, y > 0, x > 0, x < width - 1
+                ));
+                if (monitor.getBlockState() != expectedState) {
+                    okay = false;
+                    LOG.error(
+                        "Monitor {} expected to have state {}, but has state {}",
+                        monitor.getBlockState(), expectedState, monitor.getBlockState()
+                    );
+                }
+            }
+        }
+
+        if (hasPeripheral != (serverMonitor != null && serverMonitor.getTerminal() != null)) {
+            okay = false;
+            LOG.error(
+                "Peripheral is {}, but serverMonitor={} and serverMonitor.terminal={}",
+                hasPeripheral, serverMonitor, serverMonitor == null ? null : serverMonitor.getTerminal()
+            );
+        }
+
+        return okay;
+    }
 }

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

@@ -55,6 +55,12 @@ public class ServerMonitor {
         }
     }
 
+    synchronized void reset() {
+        if (terminal == null) return;
+        terminal = null;
+        markChanged();
+    }
+
     private void markChanged() {
         if (!changed.getAndSet(true)) TickScheduler.schedule(origin.tickToken);
     }

projects/common/src/main/java/dan200/computercraft/shared/peripheral/speaker/SpeakerPeripheral.java

@@ -188,7 +188,7 @@ public abstract class SpeakerPeripheral implements IPeripheral {
      * {@literal false}.
      * <p>
      * ### Valid instruments
-     * The speaker supports [all of Minecraft's noteblock instruments](https://minecraft.fandom.com/wiki/Note_Block#Instruments).
+     * The speaker supports [all of Minecraft's noteblock instruments](https://minecraft.wiki/w/Note_Block#Instruments).
      * These are:
      * <p>
      * {@code "harp"}, {@code "basedrum"}, {@code "snare"}, {@code "hat"}, {@code "bass"}, {@code "flute"},
@@ -228,7 +228,7 @@ public abstract class SpeakerPeripheral implements IPeripheral {
     /**
      * Plays a Minecraft sound through the speaker.
      * <p>
-     * This takes the [name of a Minecraft sound](https://minecraft.fandom.com/wiki/Sounds.json), such as
+     * This takes the [name of a Minecraft sound](https://minecraft.wiki/w/Sounds.json), such as
      * {@code "minecraft:block.note_block.harp"}, as well as an optional volume and pitch.
      * <p>
      * Only one sound can be played at once. This function will return {@literal false} if another sound was started

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

@@ -107,7 +107,7 @@ public class PocketServerComputer extends ServerComputer implements IPocketAcces
     @Override
     @Deprecated(forRemoval = true)
     public Map<ResourceLocation, IPeripheral> getUpgrades() {
-        return upgrade == null ? Collections.emptyMap() : Collections.singletonMap(upgrade.getUpgradeID(), getPeripheral(ComputerSide.BACK));
+        return upgrade == null ? Map.of() : Collections.singletonMap(upgrade.getUpgradeID(), getPeripheral(ComputerSide.BACK));
     }
 
     public @Nullable UpgradeData<IPocketUpgrade> getUpgrade() {

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

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.pocket.items;
 
-import com.google.common.base.Objects;
 import dan200.computercraft.annotations.ForgeOverride;
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.filesystem.Mount;
@@ -44,6 +43,7 @@ import net.minecraft.world.level.Level;
 
 import javax.annotation.Nullable;
 import java.util.List;
+import java.util.Objects;
 
 public class PocketComputerItem extends Item implements IComputerItem, IMedia, IColouredItem {
     private static final String NBT_UPGRADE = "Upgrade";
@@ -97,7 +97,7 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
 
         // Sync label
         var label = computer.getLabel();
-        if (!Objects.equal(label, getLabel(stack))) {
+        if (!Objects.equals(label, getLabel(stack))) {
             changed = true;
             setLabel(stack, label);
         }

projects/common/src/main/java/dan200/computercraft/shared/recipe/CustomShapedRecipe.java

@@ -0,0 +1,86 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.mojang.serialization.DataResult;
+import dan200.computercraft.shared.ModRegistry;
+import net.minecraft.Util;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.RecipeSerializer;
+import net.minecraft.world.item.crafting.ShapedRecipe;
+
+/**
+ * A custom version of {@link ShapedRecipe}, which can be converted to and from a {@link ShapedRecipeSpec}.
+ * <p>
+ * This recipe may both be used as a normal recipe (behaving mostly the same as {@link ShapedRecipe}, with
+ * {@linkplain RecipeUtil#itemStackFromJson(JsonObject) support for putting nbt on the result}), or subclassed to
+ * customise the crafting behaviour.
+ */
+public class CustomShapedRecipe extends ShapedRecipe {
+    private final ItemStack result;
+
+    public CustomShapedRecipe(ResourceLocation id, ShapedRecipeSpec recipe) {
+        super(
+            id,
+            recipe.properties().group(), recipe.properties().category(),
+            recipe.template().width(), recipe.template().height(), recipe.template().ingredients(),
+            recipe.result()
+        );
+        this.result = recipe.result();
+    }
+
+    public final ShapedRecipeSpec toSpec() {
+        return new ShapedRecipeSpec(RecipeProperties.of(this), ShapedTemplate.of(this), result);
+    }
+
+    @Override
+    public RecipeSerializer<? extends CustomShapedRecipe> getSerializer() {
+        return ModRegistry.RecipeSerializers.SHAPED.get();
+    }
+
+    public interface Factory<R> {
+        R create(ResourceLocation id, ShapedRecipeSpec recipe);
+    }
+
+    public static <T extends CustomShapedRecipe> RecipeSerializer<T> serialiser(CustomShapedRecipe.Factory<T> factory) {
+        return new Serialiser<>((id, r) -> DataResult.success(factory.create(id, r)));
+    }
+
+    public static <T extends CustomShapedRecipe> RecipeSerializer<T> validatingSerialiser(CustomShapedRecipe.Factory<DataResult<T>> factory) {
+        return new Serialiser<>(factory);
+    }
+
+    private record Serialiser<T extends CustomShapedRecipe>(
+        Factory<DataResult<T>> factory
+    ) implements RecipeSerializer<T> {
+        private Serialiser(Factory<DataResult<T>> factory) {
+            this.factory = (id, r) -> factory.create(id, r).flatMap(x -> {
+                if (x.getSerializer() != this) {
+                    return DataResult.error(() -> "Expected serialiser to be " + this + ", but was " + x.getSerializer());
+                }
+                return DataResult.success(x);
+            });
+        }
+
+        @Override
+        public T fromJson(ResourceLocation id, JsonObject json) {
+            return Util.getOrThrow(factory.create(id, ShapedRecipeSpec.fromJson(json)), JsonParseException::new);
+        }
+
+        @Override
+        public T fromNetwork(ResourceLocation id, FriendlyByteBuf buffer) {
+            return Util.getOrThrow(factory.create(id, ShapedRecipeSpec.fromNetwork(buffer)), IllegalStateException::new);
+        }
+
+        @Override
+        public void toNetwork(FriendlyByteBuf buffer, T recipe) {
+            recipe.toSpec().toNetwork(buffer);
+        }
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/CustomShapelessRecipe.java

@@ -0,0 +1,81 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.mojang.serialization.DataResult;
+import dan200.computercraft.shared.ModRegistry;
+import net.minecraft.Util;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.RecipeSerializer;
+import net.minecraft.world.item.crafting.ShapelessRecipe;
+
+/**
+ * A custom version of {@link ShapelessRecipe}, which can be converted to and from a {@link ShapelessRecipeSpec}.
+ * <p>
+ * This recipe may both be used as a normal recipe (behaving mostly the same as {@link ShapelessRecipe}, with
+ * {@linkplain RecipeUtil#itemStackFromJson(JsonObject) support for putting nbt on the result}), or subclassed to
+ * customise the crafting behaviour.
+ */
+public class CustomShapelessRecipe extends ShapelessRecipe {
+    private final ItemStack result;
+
+    public CustomShapelessRecipe(ResourceLocation id, ShapelessRecipeSpec recipe) {
+        super(id, recipe.properties().group(), recipe.properties().category(), recipe.result(), recipe.ingredients());
+        this.result = recipe.result();
+    }
+
+    public final ShapelessRecipeSpec toSpec() {
+        return new ShapelessRecipeSpec(RecipeProperties.of(this), getIngredients(), result);
+    }
+
+    @Override
+    public RecipeSerializer<? extends CustomShapelessRecipe> getSerializer() {
+        return ModRegistry.RecipeSerializers.SHAPELESS.get();
+    }
+
+    public interface Factory<R> {
+        R create(ResourceLocation id, ShapelessRecipeSpec recipe);
+    }
+
+    public static <T extends CustomShapelessRecipe> RecipeSerializer<T> serialiser(Factory<T> factory) {
+        return new CustomShapelessRecipe.Serialiser<>((id, r) -> DataResult.success(factory.create(id, r)));
+    }
+
+    public static <T extends CustomShapelessRecipe> RecipeSerializer<T> validatingSerialiser(Factory<DataResult<T>> factory) {
+        return new CustomShapelessRecipe.Serialiser<>(factory);
+    }
+
+    private record Serialiser<T extends CustomShapelessRecipe>(
+        Factory<DataResult<T>> factory
+    ) implements RecipeSerializer<T> {
+        private Serialiser(Factory<DataResult<T>> factory) {
+            this.factory = (id, r) -> factory.create(id, r).flatMap(x -> {
+                if (x.getSerializer() != this) {
+                    return DataResult.error(() -> "Expected serialiser to be " + this + ", but was " + x.getSerializer());
+                }
+                return DataResult.success(x);
+            });
+        }
+
+        @Override
+        public T fromJson(ResourceLocation id, JsonObject json) {
+            return Util.getOrThrow(factory.create(id, ShapelessRecipeSpec.fromJson(json)), JsonParseException::new);
+        }
+
+        @Override
+        public T fromNetwork(ResourceLocation id, FriendlyByteBuf buffer) {
+            return Util.getOrThrow(factory.create(id, ShapelessRecipeSpec.fromNetwork(buffer)), IllegalStateException::new);
+        }
+
+        @Override
+        public void toNetwork(FriendlyByteBuf buffer, T recipe) {
+            recipe.toSpec().toNetwork(buffer);
+        }
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/ImpostorShapedRecipe.java

@@ -0,0 +1,41 @@
+// Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
+//
+// SPDX-License-Identifier: LicenseRef-CCPL
+
+package dan200.computercraft.shared.recipe;
+
+import dan200.computercraft.shared.ModRegistry;
+import net.minecraft.core.RegistryAccess;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.inventory.CraftingContainer;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.CustomRecipe;
+import net.minecraft.world.item.crafting.RecipeSerializer;
+import net.minecraft.world.item.crafting.ShapedRecipe;
+import net.minecraft.world.level.Level;
+
+/**
+ * A fake {@link ShapedRecipe}, which appears in the recipe book (and other recipe mods), but cannot be crafted.
+ * <p>
+ * This is used to represent examples for our {@link CustomRecipe}s.
+ */
+public final class ImpostorShapedRecipe extends CustomShapedRecipe {
+    public ImpostorShapedRecipe(ResourceLocation id, ShapedRecipeSpec recipe) {
+        super(id, recipe);
+    }
+
+    @Override
+    public boolean matches(CraftingContainer inv, Level world) {
+        return false;
+    }
+
+    @Override
+    public ItemStack assemble(CraftingContainer inventory, RegistryAccess registryAccess) {
+        return ItemStack.EMPTY;
+    }
+
+    @Override
+    public RecipeSerializer<ImpostorShapedRecipe> getSerializer() {
+        return ModRegistry.RecipeSerializers.IMPOSTOR_SHAPED.get();
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/ImpostorShapelessRecipe.java

@@ -0,0 +1,41 @@
+// Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
+//
+// SPDX-License-Identifier: LicenseRef-CCPL
+
+package dan200.computercraft.shared.recipe;
+
+import dan200.computercraft.shared.ModRegistry;
+import net.minecraft.core.RegistryAccess;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.inventory.CraftingContainer;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.CustomRecipe;
+import net.minecraft.world.item.crafting.RecipeSerializer;
+import net.minecraft.world.item.crafting.ShapelessRecipe;
+import net.minecraft.world.level.Level;
+
+/**
+ * A fake {@link ShapelessRecipe}, which appears in the recipe book (and other recipe mods), but cannot be crafted.
+ * <p>
+ * This is used to represent examples for our {@link CustomRecipe}s.
+ */
+public final class ImpostorShapelessRecipe extends CustomShapelessRecipe {
+    public ImpostorShapelessRecipe(ResourceLocation id, ShapelessRecipeSpec recipe) {
+        super(id, recipe);
+    }
+
+    @Override
+    public boolean matches(CraftingContainer inv, Level world) {
+        return false;
+    }
+
+    @Override
+    public ItemStack assemble(CraftingContainer inventory, RegistryAccess access) {
+        return ItemStack.EMPTY;
+    }
+
+    @Override
+    public RecipeSerializer<ImpostorShapelessRecipe> getSerializer() {
+        return ModRegistry.RecipeSerializers.IMPOSTOR_SHAPELESS.get();
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/MoreCodecs.java

@@ -0,0 +1,33 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.datafixers.util.Either;
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.DataResult;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.TagParser;
+
+/**
+ * Additional codecs for working with recipes.
+ */
+public class MoreCodecs {
+    /**
+     * A codec for {@link CompoundTag}s, which either accepts a NBT-string or a JSON object.
+     */
+    public static final Codec<CompoundTag> TAG = Codec.either(Codec.STRING, CompoundTag.CODEC).flatXmap(
+        either -> either.map(MoreCodecs::parseTag, DataResult::success),
+        nbtCompound -> DataResult.success(Either.left(nbtCompound.getAsString()))
+    );
+
+    private static DataResult<CompoundTag> parseTag(String contents) {
+        try {
+            return DataResult.success(TagParser.parseTag(contents));
+        } catch (CommandSyntaxException e) {
+            return DataResult.error(e::getMessage);
+        }
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/RecipeProperties.java

@@ -0,0 +1,40 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.world.item.crafting.CraftingBookCategory;
+import net.minecraft.world.item.crafting.CraftingRecipe;
+
+/**
+ * Common properties that appear in all {@link CraftingRecipe}s.
+ *
+ * @param group    The (optional) group of the recipe, see {@link CraftingRecipe#getGroup()}.
+ * @param category The category the recipe appears in, see {@link CraftingRecipe#category()}.
+ */
+public record RecipeProperties(String group, CraftingBookCategory category) {
+    public static RecipeProperties of(CraftingRecipe recipe) {
+        return new RecipeProperties(recipe.getGroup(), recipe.category());
+    }
+
+    public static RecipeProperties fromJson(JsonObject json) {
+        var group = GsonHelper.getAsString(json, "group", "");
+        var category = CraftingBookCategory.CODEC.byName(GsonHelper.getAsString(json, "category", null), CraftingBookCategory.MISC);
+        return new RecipeProperties(group, category);
+    }
+
+    public static RecipeProperties fromNetwork(FriendlyByteBuf buffer) {
+        var group = buffer.readUtf();
+        var category = buffer.readEnum(CraftingBookCategory.class);
+        return new RecipeProperties(group, category);
+    }
+
+    public void toNetwork(FriendlyByteBuf buffer) {
+        buffer.writeUtf(group());
+        buffer.writeEnum(category());
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/RecipeUtil.java

@@ -0,0 +1,73 @@
+// SPDX-FileCopyrightText: 2017 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonSyntaxException;
+import com.mojang.serialization.JsonOps;
+import net.minecraft.Util;
+import net.minecraft.core.NonNullList;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.Ingredient;
+import net.minecraft.world.item.crafting.ShapedRecipe;
+
+public final class RecipeUtil {
+    private RecipeUtil() {
+    }
+
+    public static NonNullList<Ingredient> readIngredients(FriendlyByteBuf buffer) {
+        var count = buffer.readVarInt();
+        var ingredients = NonNullList.withSize(count, Ingredient.EMPTY);
+        for (var i = 0; i < ingredients.size(); i++) ingredients.set(i, Ingredient.fromNetwork(buffer));
+        return ingredients;
+    }
+
+    public static void writeIngredients(FriendlyByteBuf buffer, NonNullList<Ingredient> ingredients) {
+        buffer.writeCollection(ingredients, (a, b) -> b.toNetwork(a));
+    }
+
+    public static NonNullList<Ingredient> readShapelessIngredients(JsonObject json) {
+        NonNullList<Ingredient> ingredients = NonNullList.create();
+
+        var ingredientsList = GsonHelper.getAsJsonArray(json, "ingredients");
+        for (var i = 0; i < ingredientsList.size(); ++i) {
+            var ingredient = Ingredient.fromJson(ingredientsList.get(i));
+            if (!ingredient.isEmpty()) ingredients.add(ingredient);
+        }
+
+        if (ingredients.isEmpty()) throw new JsonParseException("No ingredients for shapeless recipe");
+        if (ingredients.size() > 9) {
+            throw new JsonParseException("Too many ingredients for shapeless recipe the max is 9");
+        }
+
+        return ingredients;
+    }
+
+    /**
+     * Extends {@link ShapedRecipe#itemStackFromJson(JsonObject)} with support for the {@code nbt} field.
+     *
+     * @param json The json to extract the item from.
+     * @return The parsed item stack.
+     */
+    public static ItemStack itemStackFromJson(JsonObject json) {
+        var item = ShapedRecipe.itemFromJson(json);
+        if (json.has("data")) throw new JsonParseException("Disallowed data tag found");
+
+        var count = GsonHelper.getAsInt(json, "count", 1);
+        if (count < 1) throw new JsonSyntaxException("Invalid output count: " + count);
+
+        var stack = new ItemStack(item, count);
+
+        var nbt = json.get("nbt");
+        if (nbt != null) {
+            stack.setTag(Util.getOrThrow(MoreCodecs.TAG.parse(JsonOps.INSTANCE, nbt), JsonParseException::new));
+        }
+        return stack;
+    }
+
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/ShapedRecipeSpec.java

@@ -0,0 +1,43 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.ShapedRecipe;
+
+/**
+ * A description of a {@link ShapedRecipe}.
+ * <p>
+ * This is meant to be used in conjunction with {@link CustomShapedRecipe} for more reusable serialisation and
+ * deserialisation of {@link ShapedRecipe}-like recipes.
+ *
+ * @param properties The common properties of this recipe.
+ * @param template   The shaped template of the recipe.
+ * @param result     The result of the recipe.
+ */
+public record ShapedRecipeSpec(RecipeProperties properties, ShapedTemplate template, ItemStack result) {
+    public static ShapedRecipeSpec fromJson(JsonObject json) {
+        var properties = RecipeProperties.fromJson(json);
+        var template = ShapedTemplate.fromJson(json);
+        var result = RecipeUtil.itemStackFromJson(GsonHelper.getAsJsonObject(json, "result"));
+        return new ShapedRecipeSpec(properties, template, result);
+    }
+
+    public static ShapedRecipeSpec fromNetwork(FriendlyByteBuf buffer) {
+        var properties = RecipeProperties.fromNetwork(buffer);
+        var template = ShapedTemplate.fromNetwork(buffer);
+        var result = buffer.readItem();
+        return new ShapedRecipeSpec(properties, template, result);
+    }
+
+    public void toNetwork(FriendlyByteBuf buffer) {
+        properties().toNetwork(buffer);
+        template().toNetwork(buffer);
+        buffer.writeItem(result());
+    }
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/ShapedTemplate.java

@@ -0,0 +1,99 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonSyntaxException;
+import net.minecraft.core.NonNullList;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.world.item.crafting.Ingredient;
+import net.minecraft.world.item.crafting.ShapedRecipe;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * The template for {@linkplain ShapedRecipe shaped recipes}. This largely exists for parsing shaped recipes from JSON.
+ *
+ * @param width       The width of the recipe, see {@link ShapedRecipe#getWidth()}.
+ * @param height      The height of the recipe, see {@link ShapedRecipe#getHeight()}.
+ * @param ingredients The ingredients in the recipe, see {@link ShapedRecipe#getIngredients()}
+ */
+public record ShapedTemplate(int width, int height, NonNullList<Ingredient> ingredients) {
+    public static ShapedTemplate of(ShapedRecipe recipe) {
+        return new ShapedTemplate(recipe.getWidth(), recipe.getHeight(), recipe.getIngredients());
+    }
+
+    public static ShapedTemplate fromJson(JsonObject json) {
+        Map<Character, Ingredient> key = new HashMap<>();
+        for (var entry : GsonHelper.getAsJsonObject(json, "key").entrySet()) {
+            if (entry.getKey().length() != 1) {
+                throw new JsonSyntaxException("Invalid key entry: '" + entry.getKey() + "' is an invalid symbol (must be 1 character only).");
+            }
+            if (" ".equals(entry.getKey())) {
+                throw new JsonSyntaxException("Invalid key entry: ' ' is a reserved symbol.");
+            }
+
+            key.put(entry.getKey().charAt(0), Ingredient.fromJson(entry.getValue()));
+        }
+
+        var patternList = GsonHelper.getAsJsonArray(json, "pattern");
+        if (patternList.size() == 0) {
+            throw new JsonSyntaxException("Invalid pattern: empty pattern not allowed");
+        }
+
+        var pattern = new String[patternList.size()];
+        for (var x = 0; x < pattern.length; x++) {
+            var line = GsonHelper.convertToString(patternList.get(x), "pattern[" + x + "]");
+            if (x > 0 && pattern[0].length() != line.length()) {
+                throw new JsonSyntaxException("Invalid pattern: each row must  be the same width");
+            }
+            pattern[x] = line;
+        }
+
+        var width = pattern[0].length();
+        var height = pattern.length;
+        var ingredients = NonNullList.withSize(width * height, Ingredient.EMPTY);
+
+        Set<Character> missingKeys = new HashSet<>(key.keySet());
+
+        var ingredientIdx = 0;
+        for (var line : pattern) {
+            for (var x = 0; x < line.length(); x++) {
+                var chr = line.charAt(x);
+                var ing = chr == ' ' ? Ingredient.EMPTY : key.get(chr);
+                if (ing == null) {
+                    throw new JsonSyntaxException("Pattern references symbol '" + chr + "' but it's not defined in the key");
+                }
+                ingredients.set(ingredientIdx++, ing);
+                missingKeys.remove(chr);
+            }
+        }
+
+        if (!missingKeys.isEmpty()) {
+            throw new JsonSyntaxException("Key defines symbols that aren't used in pattern: " + missingKeys);
+        }
+
+        return new ShapedTemplate(width, height, ingredients);
+    }
+
+    public static ShapedTemplate fromNetwork(FriendlyByteBuf buffer) {
+        var width = buffer.readVarInt();
+        var height = buffer.readVarInt();
+        var ingredients = NonNullList.withSize(width * height, Ingredient.EMPTY);
+        for (var i = 0; i < ingredients.size(); ++i) ingredients.set(i, Ingredient.fromNetwork(buffer));
+        return new ShapedTemplate(width, height, ingredients);
+    }
+
+    public void toNetwork(FriendlyByteBuf buffer) {
+        buffer.writeVarInt(width());
+        buffer.writeVarInt(height());
+        for (var ingredient : ingredients) ingredient.toNetwork(buffer);
+    }
+
+}

projects/common/src/main/java/dan200/computercraft/shared/recipe/ShapelessRecipeSpec.java

@@ -0,0 +1,46 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.shared.recipe;
+
+import com.google.gson.JsonObject;
+import net.minecraft.core.NonNullList;
+import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.util.GsonHelper;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.item.crafting.Ingredient;
+import net.minecraft.world.item.crafting.ShapelessRecipe;
+
+/**
+ * A description of a {@link ShapelessRecipe}.
+ * <p>
+ * This is meant to be used in conjunction with {@link CustomShapelessRecipe} for more reusable serialisation and
+ * deserialisation of {@link ShapelessRecipe}-like recipes.
+ *
+ * @param properties  The common properties of this recipe.
+ * @param ingredients The ingredients of the recipe.
+ * @param result      The result of the recipe.
+ */
+public record ShapelessRecipeSpec(RecipeProperties properties, NonNullList<Ingredient> ingredients, ItemStack result) {
+    public static ShapelessRecipeSpec fromJson(JsonObject json) {
+        var properties = RecipeProperties.fromJson(json);
+        var ingredients = RecipeUtil.readShapelessIngredients(json);
+        var result = RecipeUtil.itemStackFromJson(GsonHelper.getAsJsonObject(json, "result"));
+        return new ShapelessRecipeSpec(properties, ingredients, result);
+    }
+
+    public static ShapelessRecipeSpec fromNetwork(FriendlyByteBuf buffer) {
+        var properties = RecipeProperties.fromNetwork(buffer);
+        var ingredients = RecipeUtil.readIngredients(buffer);
+        var result = buffer.readItem();
+
+        return new ShapelessRecipeSpec(properties, ingredients, result);
+    }
+
+    public void toNetwork(FriendlyByteBuf buffer) {
+        properties().toNetwork(buffer);
+        RecipeUtil.writeIngredients(buffer, ingredients());
+        buffer.writeItem(result());
+    }
+}

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

@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.turtle.core;
 
-import com.google.common.base.Objects;
 import com.mojang.authlib.GameProfile;
 import dan200.computercraft.api.lua.ILuaCallback;
 import dan200.computercraft.api.lua.MethodResult;
@@ -455,7 +454,7 @@ public class TurtleBrain implements TurtleAccessInternal {
     }
 
     public void setOverlay(@Nullable ResourceLocation overlay) {
-        if (!Objects.equal(this.overlay, overlay)) {
+        if (!Objects.equals(this.overlay, overlay)) {
             this.overlay = overlay;
             BlockEntityHelpers.updateBlock(owner);
         }

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

@@ -27,7 +27,6 @@ import net.minecraft.world.item.context.BlockPlaceContext;
 import net.minecraft.world.item.context.UseOnContext;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.block.Block;
-import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.SignBlockEntity;
 import net.minecraft.world.level.block.entity.SignText;
 import net.minecraft.world.level.block.state.BlockState;
@@ -186,7 +185,7 @@ public class TurtlePlaceCommand implements TurtleCommand {
                 tile = world.getBlockEntity(position.relative(side));
             }
 
-            if (tile instanceof SignBlockEntity) setSignText(world, tile, message);
+            if (tile instanceof SignBlockEntity sign) setSignText(world, sign, message);
         }
 
         return placed;
@@ -220,26 +219,23 @@ public class TurtlePlaceCommand implements TurtleCommand {
         return InteractionResult.PASS;
     }
 
-    private static void setSignText(Level world, BlockEntity tile, String message) {
-        var signTile = (SignBlockEntity) tile;
-        var split = Splitter.on('\n').splitToList(message);
-        var firstLine = split.size() <= 2 ? 1 : 0;
+    private static void setSignText(Level world, SignBlockEntity sign, String message) {
+        var lines = Splitter.on('\n').splitToList(message);
+        var firstLine = lines.size() <= 2 ? 1 : 0;
 
         var signText = new SignText();
-        for (var i = 0; i < 4; i++) {
-            if (i >= firstLine && i < firstLine + split.size()) {
-                var line = split.get(i - firstLine);
-                signText.setMessage(i, line.length() > 15
+        for (int i = 0, len = Math.min(lines.size(), 4); i < len; i++) {
+            var line = lines.get(i);
+            signText = signText.setMessage(i + firstLine, line.length() > 15
                 ? Component.literal(line.substring(0, 15))
                 : Component.literal(line)
             );
         }
-        }
-        signTile.setText(signText, true);
-        world.sendBlockUpdated(tile.getBlockPos(), tile.getBlockState(), tile.getBlockState(), Block.UPDATE_ALL);
+        sign.setText(signText, true);
+        world.sendBlockUpdated(sign.getBlockPos(), sign.getBlockState(), sign.getBlockState(), Block.UPDATE_ALL);
     }
 
-    private static class ErrorMessage {
+    private static final class ErrorMessage {
         @Nullable
         String message;
     }

projects/common/src/main/java/dan200/computercraft/shared/turtle/recipes/TurtleOverlayRecipe.java

@@ -4,32 +4,30 @@
 
 package dan200.computercraft.shared.turtle.recipes;
 
-import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
-import com.google.gson.JsonParseException;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.shared.ModRegistry;
+import dan200.computercraft.shared.recipe.CustomShapelessRecipe;
+import dan200.computercraft.shared.recipe.ShapelessRecipeSpec;
 import dan200.computercraft.shared.turtle.items.TurtleItem;
-import net.minecraft.core.NonNullList;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.network.FriendlyByteBuf;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.util.GsonHelper;
 import net.minecraft.world.inventory.CraftingContainer;
 import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.crafting.*;
+import net.minecraft.world.item.crafting.RecipeSerializer;
+import net.minecraft.world.item.crafting.ShapelessRecipe;
 
 /**
  * A {@link ShapelessRecipe} which sets the {@linkplain TurtleItem#getOverlay(ItemStack)} turtle's overlay} instead.
  */
-public class TurtleOverlayRecipe extends ShapelessRecipe {
+public class TurtleOverlayRecipe extends CustomShapelessRecipe {
     private final ResourceLocation overlay;
-    private final ItemStack result;
 
-    public TurtleOverlayRecipe(ResourceLocation id, String group, CraftingBookCategory category, ItemStack result, NonNullList<Ingredient> ingredients, ResourceLocation overlay) {
-        super(id, group, category, result, ingredients);
+    public TurtleOverlayRecipe(ResourceLocation id, ShapelessRecipeSpec spec, ResourceLocation overlay) {
+        super(id, spec);
         this.overlay = overlay;
-        this.result = result;
     }
 
     private static ItemStack make(ItemStack stack, ResourceLocation overlay) {
@@ -56,63 +54,29 @@ public class TurtleOverlayRecipe extends ShapelessRecipe {
     }
 
     @Override
-    public RecipeSerializer<?> getSerializer() {
+    public RecipeSerializer<TurtleOverlayRecipe> getSerializer() {
         return ModRegistry.RecipeSerializers.TURTLE_OVERLAY.get();
     }
 
     public static class Serializer implements RecipeSerializer<TurtleOverlayRecipe> {
         @Override
         public TurtleOverlayRecipe fromJson(ResourceLocation id, JsonObject json) {
-            var group = GsonHelper.getAsString(json, "group", "");
-            var category = CraftingBookCategory.CODEC.byName(GsonHelper.getAsString(json, "category", null), CraftingBookCategory.MISC);
-            var ingredients = readIngredients(GsonHelper.getAsJsonArray(json, "ingredients"));
-
-            if (ingredients.isEmpty()) throw new JsonParseException("No ingredients for shapeless recipe");
-            if (ingredients.size() > 9) {
-                throw new JsonParseException("Too many ingredients for shapeless recipe the max is 9");
-            }
-
+            var recipe = ShapelessRecipeSpec.fromJson(json);
             var overlay = new ResourceLocation(GsonHelper.getAsString(json, "overlay"));
 
-            // We could derive this from the ingredients, but we want to avoid evaluating the ingredients too early, so
-            // it's easier to do this.
-            var result = make(ShapedRecipe.itemStackFromJson(GsonHelper.getAsJsonObject(json, "result")), overlay);
-
-            return new TurtleOverlayRecipe(id, group, category, result, ingredients, overlay);
-        }
-
-        private NonNullList<Ingredient> readIngredients(JsonArray arrays) {
-            NonNullList<Ingredient> items = NonNullList.create();
-            for (var i = 0; i < arrays.size(); ++i) {
-                var ingredient = Ingredient.fromJson(arrays.get(i));
-                if (!ingredient.isEmpty()) items.add(ingredient);
-            }
-
-            return items;
+            return new TurtleOverlayRecipe(id, recipe, overlay);
         }
 
         @Override
         public TurtleOverlayRecipe fromNetwork(ResourceLocation id, FriendlyByteBuf buffer) {
-            var group = buffer.readUtf();
-            var category = buffer.readEnum(CraftingBookCategory.class);
-            var count = buffer.readVarInt();
-            var items = NonNullList.withSize(count, Ingredient.EMPTY);
-
-            for (var j = 0; j < items.size(); j++) items.set(j, Ingredient.fromNetwork(buffer));
-            var result = buffer.readItem();
+            var recipe = ShapelessRecipeSpec.fromNetwork(buffer);
             var overlay = buffer.readResourceLocation();
-
-            return new TurtleOverlayRecipe(id, group, category, result, items, overlay);
+            return new TurtleOverlayRecipe(id, recipe, overlay);
         }
 
         @Override
         public void toNetwork(FriendlyByteBuf buffer, TurtleOverlayRecipe recipe) {
-            buffer.writeUtf(recipe.getGroup());
-            buffer.writeEnum(recipe.category());
-            buffer.writeVarInt(recipe.getIngredients().size());
-
-            for (var ingredient : recipe.getIngredients()) ingredient.toNetwork(buffer);
-            buffer.writeItem(recipe.result);
+            recipe.toSpec().toNetwork(buffer);
             buffer.writeResourceLocation(recipe.overlay);
         }
     }