Fix complaints

Sadly we have to disable -Werror, as the annotation class files are not
available on maven, so this produces a warning.

.editorconfig

@@ -11,5 +11,8 @@ insert_final_newline = true
 [*.md]
 trim_trailing_whitespace = false
 
+[*.sexp]
+indent_size = 2
+
 [*.properties]
 insert_final_newline = false

.github/workflows/main-ci.yml

@@ -0,0 +1,33 @@
+name: Build
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Set up JDK 1.8
+      uses: actions/setup-java@v1
+      with:
+        java-version: 1.8
+
+    - name: Build with Gradle
+      run: ./gradlew build --no-daemon
+
+  lint-lua:
+    name: Lint Lua
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Lint Lua code
+      run: |
+        test -d bin || mkdir bin
+        test -f bin/illuaminate || wget -q -Obin/illuaminate https://squiddev.cc/illuaminate/bin/illuaminate
+        chmod +x bin/illuaminate
+        bin/illuaminate lint

.luacheckrc

@@ -1,35 +0,0 @@
-std = "max"
-
-ignore = {
-    -- Allow access to undefined globals or their fields. In the future we'll
-    -- define all of CC's globals within this file
-    '113', '143',
-
-    -- FIXME: Ignore unused arguments and loop variables
-    '212', '213',
-
-    -- Disable line is too long for now. It would be possible to clean
-    -- this up in the future.
-    '631',
-}
-
--- Only run the linter on ROM and bios for now, as the treasure disks
--- are largely unsupported.
-include_files = {
-    'src/main/resources/assets/computercraft/lua/rom',
-    'src/main/resources/assets/computercraft/lua/bios.lua',
-    'src/test/resources/test-rom',
-}
-
-files['src/main/resources/assets/computercraft/lua/bios.lua'] = {
-    -- Allow declaring and mutating globals
-    allow_defined_top = true,
-    ignore = { '112', '121', '122', '131', '142' },
-}
-
-files['src/main/resources/assets/computercraft/lua/rom/apis'] = {
-    -- APIs may define globals on the top level. We'll ignore unused globals,
-    -- as obviously they may be used outside that API.
-    allow_defined_top = true,
-    ignore = { '131' },
-}

.travis.yml

@@ -1,14 +0,0 @@
-language: java
-
-script: ./gradlew build --no-daemon
-
-before_cache:
-  - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
-  - rm -fr $HOME/.gradle/caches/*/plugin-resolution/
-cache:
-  directories:
-    - $HOME/.gradle/caches/
-    - $HOME/.gradle/wrapper/s
-
-jdk:
-    - openjdk8

README.md

@@ -1,5 +1,5 @@
 # ![CC: Tweaked](logo.png)
-[![Current build status](https://travis-ci.org/SquidDev-CC/CC-Tweaked.svg?branch=master)](https://travis-ci.org/SquidDev-CC/CC-Tweaked "Current build status") [![Download CC: Tweaked on CurseForge](http://cf.way2muchnoise.eu/title/cc-tweaked.svg)](https://minecraft.curseforge.com/projects/cc-tweaked "Download CC: Tweaked on CurseForge")
+[![Current build status](https://github.com/SquidDev-CC/CC-Tweaked/workflows/Build/badge.svg)](https://github.com/SquidDev-CC/CC-Tweaked/actions "Current build status") [![Download CC: Tweaked on CurseForge](http://cf.way2muchnoise.eu/title/cc-tweaked.svg)](https://minecraft.curseforge.com/projects/cc-tweaked "Download CC: Tweaked on CurseForge")
 
 CC: Tweaked is a fork of [ComputerCraft](https://github.com/dan200/ComputerCraft), adding programmable computers,
 turtles and more to Minecraft.

build.gradle

@@ -9,7 +9,7 @@ buildscript {
     }
     dependencies {
         classpath 'com.google.code.gson:gson:2.8.1'
-        classpath 'net.minecraftforge.gradle:ForgeGradle:3.0.134'
+        classpath 'net.minecraftforge.gradle:ForgeGradle:3.0.154'
         classpath 'net.sf.proguard:proguard-gradle:6.1.0beta2'
         classpath 'org.ajoberstar.grgit:grgit-gradle:3.0.0'
     }
@@ -81,6 +81,10 @@ repositories {
         name "Amadornes"
         url "https://maven.amadornes.com/"
     }
+    maven {
+        name "CraftTweaker"
+        url "https://maven.blamejared.com/"
+    }
 }
 
 configurations {
@@ -90,15 +94,14 @@ configurations {
 }
 
 dependencies {
-    checkstyle "com.puppycrawl.tools:checkstyle:8.21"
+    checkstyle "com.puppycrawl.tools:checkstyle:8.25"
 
     minecraft "net.minecraftforge:forge:${mc_version}-${forge_version}"
 
-    compileOnly fg.deobf("mezz.jei:jei-1.14.3:6.0.0.7:api")
-    // deobfProvided "pl.asie:Charset-Lib:0.5.4.6"
-    // deobfProvided "MCMultiPart2:MCMultiPart:2.5.3"
+    compileOnly fg.deobf("mezz.jei:jei-1.14.4:6.0.0.25:api")
+    compileOnly fg.deobf("com.blamejared.crafttweaker:CraftTweaker-1.14.4:5.0.1.150")
 
-    runtimeOnly fg.deobf("mezz.jei:jei-1.14.3:6.0.0.7")
+    runtimeOnly fg.deobf("mezz.jei:jei-1.14.4:6.0.0.25")
 
     shade 'org.squiddev:Cobalt:0.5.0-SNAPSHOT'
 
@@ -108,15 +111,6 @@ dependencies {
     deployerJars "org.apache.maven.wagon:wagon-ssh:3.0.0"
 }
 
-sourceSets {
-    main {
-        java {
-            exclude 'dan200/computercraft/shared/integration/mcmp'
-            exclude 'dan200/computercraft/shared/integration/charset'
-        }
-    }
-}
-
 // Compile tasks
 
 javadoc {
@@ -145,7 +139,7 @@ jar {
 
 [compileJava, compileTestJava].forEach {
     it.configure {
-        options.compilerArgs << "-Xlint" << "-Xlint:-processing" << "-Werror"
+        options.compilerArgs << "-Xlint" << "-Xlint:-processing"
     }
 }
 
@@ -171,6 +165,7 @@ task proguard(type: ProGuardTask, dependsOn: jar) {
 
     // Add the main runtime jar and all non-shadowed dependencies
     libraryjars "${System.getProperty('java.home')}/lib/rt.jar"
+    libraryjars "${System.getProperty('java.home')}/lib/jce.jar"
     doFirst {
         sourceSets.main.compileClasspath
             .filter { !it.name.contains("Cobalt") }
@@ -186,9 +181,6 @@ task proguard(type: ProGuardTask, dependsOn: jar) {
     // Preserve ComputerCraft classes - we only want to strip shadowed files.
     keep 'class dan200.computercraft.** { *; }'
 
-    // Preserve the constructors in Cobalt library class, as we init them via reflection
-    keepclassmembers 'class org.squiddev.cobalt.lib.** { <init>(...); }'
-
     // LWJGL and Apache bundle Java 9 versions, which is great, but rather breaks Proguard
     dontwarn 'module-info'
     dontwarn 'org.apache.**,org.lwjgl.**'
@@ -374,6 +366,7 @@ task checkRelease {
         if (!ok) throw new IllegalStateException("Could not check release")
     }
 }
+check.dependsOn checkRelease
 
 curseforge {
     apiKey = project.hasProperty('curseForgeApiKey') ? project.curseForgeApiKey : ''
@@ -445,7 +438,9 @@ githubRelease {
     token project.hasProperty('githubApiKey') ? project.githubApiKey : ''
     owner 'SquidDev-CC'
     repo 'CC-Tweaked'
-    targetCommitish { Grgit.open(dir: '.').branch.current().name }
+    try {
+        targetCommitish = Grgit.open(dir: '.').branch.current().name
+    } catch(Exception ignored) { }
 
     tagName "v${mc_version}-${mod_version}"
     releaseName "[${mc_version}] ${mod_version}"

config/checkstyle/checkstyle.xml

@@ -14,9 +14,7 @@
         <!-- Annotations -->
         <module name="AnnotationLocation" />
         <module name="AnnotationUseStyle" />
-        <module name="MissingDeprecated">
-            <property name="skipNoJavadoc" value="true" />
-        </module>
+        <module name="MissingDeprecated" />
         <module name="MissingOverride" />
 
         <!-- Blocks -->
@@ -57,6 +55,9 @@
         <module name="SimplifyBooleanReturn" />
         <module name="StringLiteralEquality" />
         <module name="UnnecessaryParentheses" />
+        <module name="UnnecessarySemicolonAfterTypeMemberDeclaration" />
+        <module name="UnnecessarySemicolonInTryWithResources" />
+        <module name="UnnecessarySemicolonInEnumeration" />
 
         <!-- Imports -->
         <module name="CustomImportOrder" />
@@ -65,10 +66,16 @@
         <module name="UnusedImports" />
 
         <!-- Javadoc -->
+        <!-- TODO: Missing* checks for the dan200.computercraft.api package? -->
         <module name="AtclauseOrder" />
-        <!-- TODO: Cleanup our documentation before enabling JavadocMethod, JavadocStyle, JavadocType and SummaryJavadoc. -->
+        <module name="InvalidJavadocPosition" />
+        <module name="JavadocBlockTagLocation" />
+        <module name="JavadocMethod"/>
+        <module name="JavadocType"/>
+        <module name="JavadocStyle" />
         <module name="NonEmptyAtclauseDescription" />
         <module name="SingleLineJavadoc" />
+        <module name="SummaryJavadocCheck"/>
 
         <!-- Misc -->
         <module name="ArrayTypeStyle" />
@@ -155,5 +162,8 @@
 
     <module name="FileTabCharacter" />
     <module name="NewlineAtEndOfFile" />
+    <module name="RegexpSingleline">
+        <property name="format" value="\s+$"/>
+        <property name="message" value="Trailing whitespace"/>
+    </module>
 </module>
-

config/checkstyle/suppressions.xml

@@ -6,4 +6,7 @@
     <!-- All the config options and method fields. -->
     <suppress checks="StaticVariableName" files=".*[\\/]ComputerCraft.java" />
     <suppress checks="StaticVariableName" files=".*[\\/]ComputerCraftAPI.java" />
+
+    <!-- Do not check for missing package Javadoc. -->
+    <suppress checks="JavadocStyle" files=".*[\\/]package-info.java" />
 </suppressions>

gradle.properties

@@ -1,7 +1,7 @@
 # Mod properties
-mod_version=1.84.1
+mod_version=1.86.0
 
-# Minecraft properties
+# Minecraft properties (update mods.toml when changing)
 mc_version=1.14.4
-forge_version=28.0.45
-mappings_version=20190806-1.14.3
+forge_version=28.1.71
+mappings_version=20191123-1.14.3

illuaminate.sexp

@@ -0,0 +1,28 @@
+; -*- mode: Lisp;-*-
+
+(sources
+  /src/main/resources/assets/computercraft/lua/bios.lua
+  /src/main/resources/assets/computercraft/lua/rom/
+  /src/test/resources/test-rom)
+
+(at /
+  (linters
+    ;; It'd be nice to avoid this, but right now there's a lot of instances of
+    ;; it.
+    -var:set-loop
+
+    ;; It's useful to name arguments for documentation, so we allow this. It'd
+    ;; be good to find a compromise in the future, but this works for now.
+    -var:unused-arg))
+
+;; We disable the unused global linter in bios.lua and the APIs. In the future
+;; hopefully we'll get illuaminate to handle this.
+(at
+  (/src/main/resources/assets/computercraft/lua/bios.lua
+   /src/main/resources/assets/computercraft/lua/rom/apis/)
+  (linters -var:unused-global)
+  (lint
+    (allow-toplevel-global true)))
+
+;; These warnings are broken right now
+(at (bios.lua worm.lua) (linters -control:unreachable))

src/main/java/dan200/computercraft/ComputerCraft.java

@@ -6,11 +6,9 @@
 
 package dan200.computercraft;
 
-import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.turtle.event.TurtleAction;
 import dan200.computercraft.core.apis.AddressPredicate;
 import dan200.computercraft.core.apis.http.websocket.Websocket;
-import dan200.computercraft.core.filesystem.ResourceMount;
 import dan200.computercraft.shared.Config;
 import dan200.computercraft.shared.computer.blocks.BlockComputer;
 import dan200.computercraft.shared.computer.core.ClientComputerRegistry;
@@ -194,13 +192,6 @@ public final class ComputerCraft
         return "${version}";
     }
 
-    static IMount createResourceMount( String domain, String subPath )
-    {
-        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
-        ResourceMount mount = new ResourceMount( domain, subPath, manager );
-        return mount.exists( "" ) ? mount : null;
-    }
-
     public static InputStream getResourceFile( String domain, String subPath )
     {
         IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();

src/main/java/dan200/computercraft/ComputerCraftAPIImpl.java

@@ -6,6 +6,7 @@
 
 package dan200.computercraft;
 
+import com.google.common.collect.MapMaker;
 import dan200.computercraft.api.ComputerCraftAPI.IComputerCraftAPI;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
@@ -20,20 +21,26 @@ import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.core.apis.ApiFactories;
 import dan200.computercraft.core.filesystem.FileMount;
+import dan200.computercraft.core.filesystem.ResourceMount;
 import dan200.computercraft.shared.*;
 import dan200.computercraft.shared.peripheral.modem.wireless.WirelessNetwork;
 import dan200.computercraft.shared.util.IDAssigner;
 import dan200.computercraft.shared.wired.CapabilityWiredElement;
 import dan200.computercraft.shared.wired.WiredNode;
+import net.minecraft.resources.IReloadableResourceManager;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.Direction;
+import net.minecraft.util.ResourceLocation;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IBlockReader;
 import net.minecraft.world.World;
 import net.minecraftforge.common.util.LazyOptional;
+import net.minecraftforge.fml.server.ServerLifecycleHooks;
 
 import javax.annotation.Nonnull;
 import java.io.File;
+import java.lang.ref.WeakReference;
+import java.util.Map;
 
 public final class ComputerCraftAPIImpl implements IComputerCraftAPI
 {
@@ -43,6 +50,9 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
     {
     }
 
+    private WeakReference<IReloadableResourceManager> currentResources;
+    private final Map<ResourceLocation, ResourceMount> mountCache = new MapMaker().weakValues().concurrencyLevel( 1 ).makeMap();
+
     @Nonnull
     @Override
     public String getInstalledVersion()
@@ -72,7 +82,9 @@ public final class ComputerCraftAPIImpl implements IComputerCraftAPI
     @Override
     public IMount createResourceMount( @Nonnull String domain, @Nonnull String subPath )
     {
-        return ComputerCraft.createResourceMount( domain, subPath );
+        IReloadableResourceManager manager = ServerLifecycleHooks.getCurrentServer().getResourceManager();
+        ResourceMount mount = ResourceMount.get( domain, subPath, manager );
+        return mount.exists( "" ) ? mount : null;
     }
 
     @Override

src/main/java/dan200/computercraft/api/ComputerCraftAPI.java

@@ -31,8 +31,9 @@ import javax.annotation.Nullable;
 
 /**
  * The static entry point to the ComputerCraft API.
- * Members in this class must be called after mod_ComputerCraft has been initialised,
- * but may be called before it is fully loaded.
+ *
+ * Members in this class must be called after mod_ComputerCraft has been initialised, but may be called before it is
+ * fully loaded.
  */
 public final class ComputerCraftAPI
 {
@@ -189,7 +190,7 @@ public final class ComputerCraftAPI
     }
 
     /**
-     * Registers a media provider to provide {@link IMedia} implementations for Items
+     * Registers a media provider to provide {@link IMedia} implementations for Items.
      *
      * @param provider The media provider to register.
      * @see IMediaProvider
@@ -220,7 +221,7 @@ public final class ComputerCraftAPI
     }
 
     /**
-     * Construct a new wired node for a given wired element
+     * Construct a new wired node for a given wired element.
      *
      * @param element The element to construct it for
      * @return The element's node
@@ -233,7 +234,7 @@ public final class ComputerCraftAPI
     }
 
     /**
-     * Get the wired network element for a block in world
+     * Get the wired network element for a block in world.
      *
      * @param world The world the block exists in
      * @param pos   The position the block exists in

src/main/java/dan200/computercraft/api/filesystem/IMount.java

@@ -19,7 +19,7 @@ import java.util.List;
 
 /**
  * Represents a read only part of a virtual filesystem that can be mounted onto a computer using
- * {@link IComputerAccess#mount(String, IMount)}
+ * {@link IComputerAccess#mount(String, IMount)}.
  *
  * Ready made implementations of this interface can be created using
  * {@link ComputerCraftAPI#createSaveDirMount(World, String, long)} or
@@ -60,7 +60,7 @@ public interface IMount
     void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException;
 
     /**
-     * Returns the size of a file with a given path, in bytes
+     * Returns the size of a file with a given path, in bytes.
      *
      * @param path A file path in normalised format, relative to the mount location. ie: "programs/myprogram".
      * @return The size of the file, in bytes.

src/main/java/dan200/computercraft/api/lua/ArgumentHelper.java

@@ -0,0 +1,335 @@
+/*
+ * This file is part of the public ComputerCraft API - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. This API may be redistributed unmodified and in full only.
+ * For help using the API, and posting your mods, visit the forums at computercraft.info.
+ */
+
+package dan200.computercraft.api.lua;
+
+import dan200.computercraft.api.peripheral.IComputerAccess;
+import dan200.computercraft.api.peripheral.IPeripheral;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.Map;
+
+/**
+ * Provides methods for extracting values and validating Lua arguments, such as those provided to
+ * {@link ILuaObject#callMethod(ILuaContext, int, Object[])} or
+ * {@link IPeripheral#callMethod(IComputerAccess, ILuaContext, int, Object[])}.
+ *
+ * This provides two sets of functions: the {@code get*} methods, which require an argument to be valid, and
+ * {@code opt*}, which accept a default value and return that if the argument was not present or was {@code null}.
+ * If the argument is of the wrong type, a suitable error message will be thrown, with a similar format to Lua's own
+ * error messages.
+ *
+ * <h2>Example usage:</h2>
+ * <pre>
+ * {@code
+ * int slot = getInt( args, 0 );
+ * int amount = optInt( args, 1, 64 );
+ * }
+ * </pre>
+ */
+public final class ArgumentHelper
+{
+    private ArgumentHelper()
+    {
+    }
+
+    /**
+     * Get a string representation of the given value's type.
+     *
+     * @param value The value whose type we are trying to compute.
+     * @return A string representation of the given value's type, in a similar format to that provided by Lua's
+     * {@code type} function.
+     */
+    @Nonnull
+    public static String getType( @Nullable Object value )
+    {
+        if( value == null ) return "nil";
+        if( value instanceof String ) return "string";
+        if( value instanceof Boolean ) return "boolean";
+        if( value instanceof Number ) return "number";
+        if( value instanceof Map ) return "table";
+        return "userdata";
+    }
+
+    /**
+     * Construct a "bad argument" exception, from an expected type and the actual value provided.
+     *
+     * @param index    The argument number, starting from 0.
+     * @param expected The expected type for this argument.
+     * @param actual   The actual value provided for this argument.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badArgumentOf( int index, @Nonnull String expected, @Nullable Object actual )
+    {
+        return badArgument( index, expected, getType( actual ) );
+    }
+
+    /**
+     * Construct a "bad argument" exception, from an expected and actual type.
+     *
+     * @param index    The argument number, starting from 0.
+     * @param expected The expected type for this argument.
+     * @param actual   The provided type for this argument.
+     * @return The constructed exception, which should be thrown immediately.
+     */
+    @Nonnull
+    public static LuaException badArgument( int index, @Nonnull String expected, @Nonnull String actual )
+    {
+        return new LuaException( "bad argument #" + (index + 1) + " (" + expected + " expected, got " + actual + ")" );
+    }
+
+    /**
+     * Get an argument as a double.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a number.
+     * @see #getFiniteDouble(Object[], int) if you require this to be finite (i.e. not infinite or NaN).
+     */
+    public static double getDouble( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        if( index >= args.length ) throw badArgument( index, "number", "nil" );
+        Object value = args[index];
+        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
+        return ((Number) value).doubleValue();
+    }
+
+    /**
+     * Get an argument as an integer.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not an integer.
+     */
+    public static int getInt( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        return (int) getLong( args, index );
+    }
+
+    /**
+     * Get an argument as a long.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a long.
+     */
+    public static long getLong( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        if( index >= args.length ) throw badArgument( index, "number", "nil" );
+        Object value = args[index];
+        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
+        return checkFinite( index, (Number) value ).longValue();
+    }
+
+    /**
+     * Get an argument as a finite number (not infinite or NaN).
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not finite.
+     */
+    public static double getFiniteDouble( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        return checkFinite( index, getDouble( args, index ) );
+    }
+
+    /**
+     * Get an argument as a boolean.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a boolean.
+     */
+    public static boolean getBoolean( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        if( index >= args.length ) throw badArgument( index, "boolean", "nil" );
+        Object value = args[index];
+        if( !(value instanceof Boolean) ) throw badArgumentOf( index, "boolean", value );
+        return (Boolean) value;
+    }
+
+    /**
+     * Get an argument as a string.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a string.
+     */
+    @Nonnull
+    public static String getString( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        if( index >= args.length ) throw badArgument( index, "string", "nil" );
+        Object value = args[index];
+        if( !(value instanceof String) ) throw badArgumentOf( index, "string", value );
+        return (String) value;
+    }
+
+    /**
+     * Get an argument as a table.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @return The argument's value.
+     * @throws LuaException If the value is not a table.
+     */
+    @Nonnull
+    public static Map<?, ?> getTable( @Nonnull Object[] args, int index ) throws LuaException
+    {
+        if( index >= args.length ) throw badArgument( index, "table", "nil" );
+        Object value = args[index];
+        if( !(value instanceof Map) ) throw badArgumentOf( index, "table", value );
+        return (Map<?, ?>) value;
+    }
+
+    /**
+     * Get an argument as a double.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    public static double optDouble( @Nonnull Object[] args, int index, double def ) throws LuaException
+    {
+        Object value = index < args.length ? args[index] : null;
+        if( value == null ) return def;
+        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
+        return ((Number) value).doubleValue();
+    }
+
+    /**
+     * Get an argument as an int.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    public static int optInt( @Nonnull Object[] args, int index, int def ) throws LuaException
+    {
+        return (int) optLong( args, index, def );
+    }
+
+    /**
+     * Get an argument as a long.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a number.
+     */
+    public static long optLong( @Nonnull Object[] args, int index, long def ) throws LuaException
+    {
+        Object value = index < args.length ? args[index] : null;
+        if( value == null ) return def;
+        if( !(value instanceof Number) ) throw badArgumentOf( index, "number", value );
+        return checkFinite( index, (Number) value ).longValue();
+    }
+
+    /**
+     * Get an argument as a finite number (not infinite or NaN).
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not finite.
+     */
+    public static double optFiniteDouble( @Nonnull Object[] args, int index, double def ) throws LuaException
+    {
+        return checkFinite( index, optDouble( args, index, def ) );
+    }
+
+    /**
+     * Get an argument as a boolean.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a boolean.
+     */
+    public static boolean optBoolean( @Nonnull Object[] args, int index, boolean def ) throws LuaException
+    {
+        Object value = index < args.length ? args[index] : null;
+        if( value == null ) return def;
+        if( !(value instanceof Boolean) ) throw badArgumentOf( index, "boolean", value );
+        return (Boolean) value;
+    }
+
+    /**
+     * Get an argument as a string.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a string.
+     */
+    public static String optString( @Nonnull Object[] args, int index, String def ) throws LuaException
+    {
+        Object value = index < args.length ? args[index] : null;
+        if( value == null ) return def;
+        if( !(value instanceof String) ) throw badArgumentOf( index, "string", value );
+        return (String) value;
+    }
+
+    /**
+     * Get an argument as a table.
+     *
+     * @param args  The arguments to extract from.
+     * @param index The index into the argument array to read from.
+     * @param def   The default value, if this argument is not given.
+     * @return The argument's value, or {@code def} if none was provided.
+     * @throws LuaException If the value is not a table.
+     */
+    public static Map<?, ?> optTable( @Nonnull Object[] args, int index, Map<Object, Object> def ) throws LuaException
+    {
+        Object value = index < args.length ? args[index] : null;
+        if( value == null ) return def;
+        if( !(value instanceof Map) ) throw badArgumentOf( index, "table", value );
+        return (Map<?, ?>) value;
+    }
+
+    private static Number checkFinite( int index, Number value ) throws LuaException
+    {
+        checkFinite( index, value.doubleValue() );
+        return value;
+    }
+
+    private static double checkFinite( int index, double value ) throws LuaException
+    {
+        if( !Double.isFinite( value ) ) throw badArgument( index, "number", getNumericType( value ) );
+        return value;
+    }
+
+    /**
+     * Returns a more detailed representation of this number's type. If this is finite, it will just return "number",
+     * otherwise it returns whether it is infinite or NaN.
+     *
+     * @param value The value to extract the type for.
+     * @return This value's numeric type.
+     */
+    @Nonnull
+    public static String getNumericType( double value )
+    {
+        if( Double.isNaN( value ) ) return "nan";
+        if( value == Double.POSITIVE_INFINITY ) return "inf";
+        if( value == Double.NEGATIVE_INFINITY ) return "-inf";
+        return "number";
+    }
+}

src/main/java/dan200/computercraft/api/lua/IComputerSystem.java

@@ -26,7 +26,7 @@ public interface IComputerSystem extends IComputerAccess
     IFileSystem getFileSystem();
 
     /**
-     * Get the label for this computer
+     * Get the label for this computer.
      *
      * @return This computer's label, or {@code null} if it is not set.
      */

src/main/java/dan200/computercraft/api/peripheral/IPeripheral.java

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.api.peripheral;
 
+import dan200.computercraft.api.lua.ArgumentHelper;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
 
@@ -58,9 +59,11 @@ public interface IPeripheral
      *                  Lua values of type "table" will be represented by Object type Map.<br>
      *                  Lua values of any other type will be represented by a null object.<br>
      *                  This array will be empty if no arguments are passed.
+     *
+     *                  It is recommended you use {@link ArgumentHelper} in order to validate and process arguments.
      * @return An array of objects, representing values you wish to return to the lua program. Integers, Doubles, Floats,
-     * Strings, Booleans, Maps and ILuaObject and null be converted to their corresponding lua type. All other types
-     * will be converted to nil.
+     * Strings, Booleans, Maps, ILuaObject and null be converted to their corresponding lua type. All other types will
+     * be converted to nil.
      *
      * You may return null to indicate no values should be returned.
      * @throws LuaException         If you throw any exception from this function, a lua error will be raised with the
@@ -70,6 +73,7 @@ public interface IPeripheral
      *                              InterruptedException will be thrown. This exception must not be caught or
      *                              intercepted, or the computer will leak memory and end up in a broken state.
      * @see #getMethodNames
+     * @see ArgumentHelper
      */
     @Nullable
     Object[] callMethod( @Nonnull IComputerAccess computer, @Nonnull ILuaContext context, int method, @Nonnull Object[] arguments ) throws LuaException, InterruptedException;

src/main/java/dan200/computercraft/api/pocket/IPocketAccess.java

@@ -16,7 +16,7 @@ import javax.annotation.Nullable;
 import java.util.Map;
 
 /**
- * Wrapper class for pocket computers
+ * Wrapper class for pocket computers.
  */
 public interface IPocketAccess
 {

src/main/java/dan200/computercraft/api/turtle/TurtleSide.java

@@ -12,12 +12,12 @@ package dan200.computercraft.api.turtle;
 public enum TurtleSide
 {
     /**
-     * The turtle's left side (where the pickaxe usually is on a Wireless Mining Turtle)
+     * The turtle's left side (where the pickaxe usually is on a Wireless Mining Turtle).
      */
     Left,
 
     /**
-     * The turtle's right side (where the modem usually is on a Wireless Mining Turtle)
+     * The turtle's right side (where the modem usually is on a Wireless Mining Turtle).
      */
     Right,
 }

src/main/java/dan200/computercraft/api/turtle/TurtleVerb.java

@@ -18,12 +18,12 @@ import net.minecraft.util.Direction;
 public enum TurtleVerb
 {
     /**
-     * The turtle called {@code turtle.dig()}, {@code turtle.digUp()} or {@code turtle.digDown()}
+     * The turtle called {@code turtle.dig()}, {@code turtle.digUp()} or {@code turtle.digDown()}.
      */
     Dig,
 
     /**
-     * The turtle called {@code turtle.attack()}, {@code turtle.attackUp()} or {@code turtle.attackDown()}
+     * The turtle called {@code turtle.attack()}, {@code turtle.attackUp()} or {@code turtle.attackDown()}.
      */
     Attack,
 }

src/main/java/dan200/computercraft/api/turtle/event/TurtleAction.java

@@ -71,7 +71,7 @@ public enum TurtleAction
     EQUIP,
 
     /**
-     * Inspect a block in world
+     * Inspect a block in world.
      *
      * @see TurtleBlockEvent.Inspect
      */

src/main/java/dan200/computercraft/api/turtle/event/TurtleBlockEvent.java

@@ -112,7 +112,7 @@ public abstract class TurtleBlockEvent extends TurtlePlayerEvent
         }
 
         /**
-         * Get the upgrade doing the digging
+         * Get the upgrade doing the digging.
          *
          * @return The upgrade doing the digging.
          */

src/main/java/dan200/computercraft/api/turtle/event/TurtleInventoryEvent.java

@@ -31,7 +31,7 @@ public abstract class TurtleInventoryEvent extends TurtleBlockEvent
     }
 
     /**
-     * Get the inventory being interacted with
+     * Get the inventory being interacted with.
      *
      * @return The inventory being interacted with, {@code null} if the item will be dropped to/sucked from the world.
      */

src/main/java/dan200/computercraft/client/ClientRegistry.java

@@ -12,6 +12,7 @@ import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.media.items.ItemDisk;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
+import net.minecraft.client.Minecraft;
 import net.minecraft.client.renderer.model.IBakedModel;
 import net.minecraft.client.renderer.model.IUnbakedModel;
 import net.minecraft.client.renderer.model.ModelResourceLocation;
@@ -58,8 +59,8 @@ public final class ClientRegistry
     };
 
     private static final String[] EXTRA_TEXTURES = new String[] {
-        // TODO: Gather these automatically from the model. I'm unable to get this working with Forge's current
-        //  model loading code.
+        // TODO: Gather these automatically from the model. Sadly the model loader isn't available
+        //  when stitching textures.
         "block/turtle_colour",
         "block/turtle_elf_overlay",
         "block/turtle_crafty_face",
@@ -77,13 +78,12 @@ public final class ClientRegistry
     @SubscribeEvent
     public static void onTextureStitchEvent( TextureStitchEvent.Pre event )
     {
-        /*
-        IResourceManager manager = Minecraft.getInstance().getResourceManager();
+        if( event.getMap() != Minecraft.getInstance().getTextureMap() ) return;
+
         for( String extra : EXTRA_TEXTURES )
         {
-            // TODO: event.getMap().registerSprite( manager, new ResourceLocation( ComputerCraft.MOD_ID, extra ) );
+            event.addSprite( new ResourceLocation( ComputerCraft.MOD_ID, extra ) );
         }
-        */
     }
 
     @SubscribeEvent

src/main/java/dan200/computercraft/client/gui/GuiComputer.java

@@ -176,11 +176,4 @@ public final class GuiComputer<T extends ContainerComputerBase> extends Containe
         return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
             || super.mouseDragged( x, y, button, deltaX, deltaY );
     }
-
-    @Override
-    public boolean mouseReleased( double x, double y, int button )
-    {
-        return (getFocused() != null && getFocused().mouseReleased( x, y, button ))
-            || super.mouseReleased( x, y, button );
-    }
 }

src/main/java/dan200/computercraft/client/gui/GuiTurtle.java

@@ -129,4 +129,11 @@ public class GuiTurtle extends ContainerScreen<ContainerTurtle>
         super.render( mouseX, mouseY, partialTicks );
         renderHoveredToolTip( mouseX, mouseY );
     }
+
+    @Override
+    public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
+    {
+        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+            || super.mouseDragged( x, y, button, deltaX, deltaY );
+    }
 }

src/main/java/dan200/computercraft/client/gui/widgets/WidgetTerminal.java

@@ -241,11 +241,12 @@ public class WidgetTerminal implements IGuiEventListener
             charX = Math.min( Math.max( charX, 0 ), term.getWidth() - 1 );
             charY = Math.min( Math.max( charY, 0 ), term.getHeight() - 1 );
 
-            computer.mouseDrag( button + 1, charX + 1, charY + 1 );
-
-            lastMouseX = charX;
-            lastMouseY = charY;
-            lastMouseButton = button;
+            if( button == lastMouseButton && (charX != lastMouseX || charY != lastMouseY) )
+            {
+                computer.mouseDrag( button + 1, charX + 1, charY + 1 );
+                lastMouseX = charX;
+                lastMouseY = charY;
+            }
         }
 
         return false;
@@ -427,4 +428,10 @@ public class WidgetTerminal implements IGuiEventListener
         ClientComputer computer = this.computer.get();
         if( computer != null ) computer.queueEvent( event, args );
     }
+
+    @Override
+    public boolean isMouseOver( double x, double y )
+    {
+        return true;
+    }
 }

src/main/java/dan200/computercraft/client/gui/widgets/WidgetWrapper.java

@@ -95,4 +95,11 @@ public class WidgetWrapper implements IGuiEventListener
     {
         return height;
     }
+
+    @Override
+    public boolean isMouseOver( double x, double y )
+    {
+        double dx = x - this.x, dy = y - this.y;
+        return dx >= 0 && dx < width && dy >= 0 && dy < height;
+    }
 }

src/main/java/dan200/computercraft/client/render/ItemMapLikeRenderer.java

@@ -18,7 +18,7 @@ import net.minecraft.util.math.MathHelper;
 public abstract class ItemMapLikeRenderer
 {
     /**
-     * The main rendering method for the item
+     * The main rendering method for the item.
      *
      * @param stack The stack to render
      * @see FirstPersonRenderer#renderMapFirstPerson(ItemStack)
@@ -87,7 +87,7 @@ public abstract class ItemMapLikeRenderer
     }
 
     /**
-     * Render an item in the middle of the screen
+     * Render an item in the middle of the screen.
      *
      * @param pitch         The pitch of the player
      * @param equipProgress The equip progress of this item

src/main/java/dan200/computercraft/client/render/ItemPocketRenderer.java

@@ -32,7 +32,7 @@ import static dan200.computercraft.client.gui.FixedWidthFontRenderer.*;
 import static dan200.computercraft.client.gui.GuiComputer.*;
 
 /**
- * Emulates map rendering for pocket computers
+ * Emulates map rendering for pocket computers.
  */
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class ItemPocketRenderer extends ItemMapLikeRenderer

src/main/java/dan200/computercraft/client/render/ItemPrintoutRenderer.java

@@ -23,7 +23,7 @@ import static dan200.computercraft.shared.media.items.ItemPrintout.LINES_PER_PAG
 import static dan200.computercraft.shared.media.items.ItemPrintout.LINE_MAX_LENGTH;
 
 /**
- * Emulates map and item-frame rendering for printouts
+ * Emulates map and item-frame rendering for printouts.
  */
 @Mod.EventBusSubscriber( modid = ComputerCraft.MOD_ID, value = Dist.CLIENT )
 public final class ItemPrintoutRenderer extends ItemMapLikeRenderer

src/main/java/dan200/computercraft/client/render/PrintoutRenderer.java

@@ -28,32 +28,32 @@ public final class PrintoutRenderer
     private static final double BG_SIZE = 256.0;
 
     /**
-     * Width of a page
+     * Width of a page.
      */
     public static final int X_SIZE = 172;
 
     /**
-     * Height of a page
+     * Height of a page.
      */
     public static final int Y_SIZE = 209;
 
     /**
-     * Padding between the left and right of a page and the text
+     * Padding between the left and right of a page and the text.
      */
     public static final int X_TEXT_MARGIN = 13;
 
     /**
-     * Padding between the top and bottom of a page and the text
+     * Padding between the top and bottom of a page and the text.
      */
     public static final int Y_TEXT_MARGIN = 11;
 
     /**
-     * Width of the extra page texture
+     * Width of the extra page texture.
      */
     private static final int X_FOLD_SIZE = 12;
 
     /**
-     * Size of the leather cover
+     * Size of the leather cover.
      */
     public static final int COVER_SIZE = 12;
 

src/main/java/dan200/computercraft/client/render/TileEntityCableRenderer.java

@@ -105,6 +105,8 @@ public class TileEntityCableRenderer extends TileEntityRenderer<TileCable>
     }
 
     /**
+     * Set up the state for rendering block-breaking progress.
+     *
      * @see WorldRenderer#preRenderDamagedBlocks()
      */
     private void preRenderDamagedBlocks()
@@ -123,6 +125,8 @@ public class TileEntityCableRenderer extends TileEntityRenderer<TileCable>
     }
 
     /**
+     * Tear down the state for rendering block-breaking progress.
+     *
      * @see WorldRenderer#postRenderDamagedBlocks()
      */
     private void postRenderDamagedBlocks()

src/main/java/dan200/computercraft/core/apis/AddressPredicate.java

@@ -160,7 +160,7 @@ public class AddressPredicate
     }
 
     /**
-     * Determine whether the given address matches a series of patterns
+     * Determine whether the given address matches a series of patterns.
      *
      * @param address The address to check.
      * @return Whether it matches any of these patterns.

src/main/java/dan200/computercraft/core/apis/ArgumentHelper.java

@@ -13,256 +13,106 @@ import javax.annotation.Nullable;
 import java.util.Map;
 
 /**
- * Various helpers for arguments
+ * A stub for any mods which depended on this version of the argument helper.
+ *
+ * @deprecated Use {@link dan200.computercraft.api.lua.ArgumentHelper}.
  */
+@Deprecated
 public final class ArgumentHelper
 {
     private ArgumentHelper()
     {
-        throw new IllegalStateException( "Cannot instantiate singleton " + getClass().getName() );
     }
 
     @Nonnull
     public static String getType( @Nullable Object type )
     {
-        if( type == null ) return "nil";
-        if( type instanceof String ) return "string";
-        if( type instanceof Boolean ) return "boolean";
-        if( type instanceof Number ) return "number";
-        if( type instanceof Map ) return "table";
-
-        Class<?> klass = type.getClass();
-        if( klass.isArray() )
-        {
-            StringBuilder name = new StringBuilder();
-            while( klass.isArray() )
-            {
-                name.append( "[]" );
-                klass = klass.getComponentType();
-            }
-            name.insert( 0, klass.getName() );
-            return name.toString();
-        }
-        else
-        {
-            return klass.getName();
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.getType( type );
     }
 
     @Nonnull
     public static LuaException badArgument( int index, @Nonnull String expected, @Nullable Object actual )
     {
-        return badArgument( index, expected, getType( actual ) );
+        return dan200.computercraft.api.lua.ArgumentHelper.badArgumentOf( index, expected, actual );
     }
 
     @Nonnull
     public static LuaException badArgument( int index, @Nonnull String expected, @Nonnull String actual )
     {
-        return new LuaException( "bad argument #" + (index + 1) + " (" + expected + " expected, got " + actual + ")" );
+        return dan200.computercraft.api.lua.ArgumentHelper.badArgument( index, expected, actual );
     }
 
     public static double getNumber( @Nonnull Object[] args, int index ) throws LuaException
     {
-        if( index >= args.length ) throw badArgument( index, "number", "nil" );
-        Object value = args[index];
-        if( value instanceof Number )
-        {
-            return ((Number) value).doubleValue();
-        }
-        else
-        {
-            throw badArgument( index, "number", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.getDouble( args, index );
     }
 
     public static int getInt( @Nonnull Object[] args, int index ) throws LuaException
     {
-        return (int) getLong( args, index );
+        return dan200.computercraft.api.lua.ArgumentHelper.getInt( args, index );
     }
 
     public static long getLong( @Nonnull Object[] args, int index ) throws LuaException
     {
-        if( index >= args.length ) throw badArgument( index, "number", "nil" );
-        Object value = args[index];
-        if( value instanceof Number )
-        {
-            return checkReal( index, (Number) value ).longValue();
-        }
-        else
-        {
-            throw badArgument( index, "number", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.getLong( args, index );
     }
 
     public static double getReal( @Nonnull Object[] args, int index ) throws LuaException
     {
-        return checkReal( index, getNumber( args, index ) );
+        return dan200.computercraft.api.lua.ArgumentHelper.getFiniteDouble( args, index );
     }
 
     public static boolean getBoolean( @Nonnull Object[] args, int index ) throws LuaException
     {
-        if( index >= args.length ) throw badArgument( index, "boolean", "nil" );
-        Object value = args[index];
-        if( value instanceof Boolean )
-        {
-            return (Boolean) value;
-        }
-        else
-        {
-            throw badArgument( index, "boolean", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.getBoolean( args, index );
     }
 
     @Nonnull
     public static String getString( @Nonnull Object[] args, int index ) throws LuaException
     {
-        if( index >= args.length ) throw badArgument( index, "string", "nil" );
-        Object value = args[index];
-        if( value instanceof String )
-        {
-            return (String) value;
-        }
-        else
-        {
-            throw badArgument( index, "string", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.getString( args, index );
     }
 
-    @SuppressWarnings( "unchecked" )
     @Nonnull
+    @SuppressWarnings( "unchecked" )
     public static Map<Object, Object> getTable( @Nonnull Object[] args, int index ) throws LuaException
     {
-        if( index >= args.length ) throw badArgument( index, "table", "nil" );
-        Object value = args[index];
-        if( value instanceof Map )
-        {
-            return (Map<Object, Object>) value;
-        }
-        else
-        {
-            throw badArgument( index, "table", value );
-        }
+        return (Map<Object, Object>) dan200.computercraft.api.lua.ArgumentHelper.getTable( args, index );
     }
 
     public static double optNumber( @Nonnull Object[] args, int index, double def ) throws LuaException
     {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null )
-        {
-            return def;
-        }
-        else if( value instanceof Number )
-        {
-            return ((Number) value).doubleValue();
-        }
-        else
-        {
-            throw badArgument( index, "number", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.optDouble( args, index, def );
     }
 
     public static int optInt( @Nonnull Object[] args, int index, int def ) throws LuaException
     {
-        return (int) optLong( args, index, def );
+        return dan200.computercraft.api.lua.ArgumentHelper.optInt( args, index, def );
     }
 
     public static long optLong( @Nonnull Object[] args, int index, long def ) throws LuaException
     {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null )
-        {
-            return def;
-        }
-        else if( value instanceof Number )
-        {
-            return checkReal( index, (Number) value ).longValue();
-        }
-        else
-        {
-            throw badArgument( index, "number", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.optLong( args, index, def );
     }
 
     public static double optReal( @Nonnull Object[] args, int index, double def ) throws LuaException
     {
-        return checkReal( index, optNumber( args, index, def ) );
+        return dan200.computercraft.api.lua.ArgumentHelper.optFiniteDouble( args, index, def );
     }
 
     public static boolean optBoolean( @Nonnull Object[] args, int index, boolean def ) throws LuaException
     {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null )
-        {
-            return def;
-        }
-        else if( value instanceof Boolean )
-        {
-            return (Boolean) value;
-        }
-        else
-        {
-            throw badArgument( index, "boolean", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.optBoolean( args, index, def );
     }
 
     public static String optString( @Nonnull Object[] args, int index, String def ) throws LuaException
     {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null )
-        {
-            return def;
-        }
-        else if( value instanceof String )
-        {
-            return (String) value;
-        }
-        else
-        {
-            throw badArgument( index, "string", value );
-        }
+        return dan200.computercraft.api.lua.ArgumentHelper.optString( args, index, def );
     }
 
     @SuppressWarnings( "unchecked" )
     public static Map<Object, Object> optTable( @Nonnull Object[] args, int index, Map<Object, Object> def ) throws LuaException
     {
-        Object value = index < args.length ? args[index] : null;
-        if( value == null )
-        {
-            return def;
-        }
-        else if( value instanceof Map )
-        {
-            return (Map<Object, Object>) value;
-        }
-        else
-        {
-            throw badArgument( index, "table", value );
-        }
-    }
-
-    private static Number checkReal( int index, Number value ) throws LuaException
-    {
-        checkReal( index, value.doubleValue() );
-        return value;
-    }
-
-    private static double checkReal( int index, double value ) throws LuaException
-    {
-        if( Double.isNaN( value ) )
-        {
-            throw badArgument( index, "number", "nan" );
-        }
-        else if( value == Double.POSITIVE_INFINITY )
-        {
-            throw badArgument( index, "number", "inf" );
-        }
-        else if( value == Double.NEGATIVE_INFINITY )
-        {
-            throw badArgument( index, "number", "-inf" );
-        }
-        else
-        {
-            return value;
-        }
+        return (Map<Object, Object>) dan200.computercraft.api.lua.ArgumentHelper.optTable( args, index, def );
     }
 }

src/main/java/dan200/computercraft/core/apis/FSAPI.java

@@ -27,7 +27,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.function.Function;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
 
 public class FSAPI implements ILuaAPI
 {

src/main/java/dan200/computercraft/core/apis/HTTPAPI.java

@@ -23,7 +23,7 @@ import java.util.Collections;
 import java.util.Locale;
 import java.util.Map;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.*;
+import static dan200.computercraft.api.lua.ArgumentHelper.*;
 import static dan200.computercraft.core.apis.TableHelper.*;
 
 public class HTTPAPI implements ILuaAPI
@@ -89,7 +89,7 @@ public class HTTPAPI implements ILuaAPI
             case 0: // request
             {
                 String address, postString, requestMethod;
-                Map<Object, Object> headerTable;
+                Map<?, ?> headerTable;
                 boolean binary, redirect;
 
                 if( args.length >= 1 && args[0] instanceof Map )
@@ -172,7 +172,7 @@ public class HTTPAPI implements ILuaAPI
             case 2: // websocket
             {
                 String address = getString( args, 0 );
-                Map<Object, Object> headerTbl = optTable( args, 1, Collections.emptyMap() );
+                Map<?, ?> headerTbl = optTable( args, 1, Collections.emptyMap() );
 
                 if( !ComputerCraft.http_websocket_enable )
                 {

src/main/java/dan200/computercraft/core/apis/OSAPI.java

@@ -19,7 +19,7 @@ import java.time.ZonedDateTime;
 import java.time.format.DateTimeFormatterBuilder;
 import java.util.*;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.*;
+import static dan200.computercraft.api.lua.ArgumentHelper.*;
 
 public class OSAPI implements ILuaAPI
 {
@@ -229,7 +229,7 @@ public class OSAPI implements ILuaAPI
             case 1:
             {
                 // startTimer
-                double timer = getReal( args, 0 );
+                double timer = getFiniteDouble( args, 0 );
                 synchronized( m_timers )
                 {
                     m_timers.put( m_nextTimerToken, new Timer( (int) Math.round( timer / 0.05 ) ) );
@@ -239,7 +239,7 @@ public class OSAPI implements ILuaAPI
             case 2:
             {
                 // setAlarm
-                double time = getReal( args, 0 );
+                double time = getFiniteDouble( args, 0 );
                 if( time < 0.0 || time >= 24.0 )
                 {
                     throw new LuaException( "Number out of range" );

src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java

@@ -22,7 +22,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
 
 public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChangeListener
 {

src/main/java/dan200/computercraft/core/apis/RedstoneAPI.java

@@ -15,7 +15,7 @@ import javax.annotation.Nonnull;
 import java.util.HashMap;
 import java.util.Map;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.*;
+import static dan200.computercraft.api.lua.ArgumentHelper.*;
 
 public class RedstoneAPI implements ILuaAPI
 {

src/main/java/dan200/computercraft/core/apis/TableHelper.java

@@ -6,14 +6,17 @@
 
 package dan200.computercraft.core.apis;
 
+import dan200.computercraft.api.lua.ArgumentHelper;
 import dan200.computercraft.api.lua.LuaException;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.Map;
 
+import static dan200.computercraft.api.lua.ArgumentHelper.getNumericType;
+
 /**
- * Various helpers for tables
+ * Various helpers for tables.
  */
 public final class TableHelper
 {
@@ -200,21 +203,7 @@ public final class TableHelper
 
     private static double checkReal( @Nonnull String key, double value ) throws LuaException
     {
-        if( Double.isNaN( value ) )
-        {
-            throw badKey( key, "number", "nan" );
-        }
-        else if( value == Double.POSITIVE_INFINITY )
-        {
-            throw badKey( key, "number", "inf" );
-        }
-        else if( value == Double.NEGATIVE_INFINITY )
-        {
-            throw badKey( key, "number", "-inf" );
-        }
-        else
-        {
-            return value;
-        }
+        if( !Double.isFinite( value ) ) throw badKey( key, "number", getNumericType( value ) );
+        return value;
     }
 }

src/main/java/dan200/computercraft/core/apis/TermAPI.java

@@ -17,7 +17,7 @@ import org.apache.commons.lang3.ArrayUtils;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.*;
+import static dan200.computercraft.api.lua.ArgumentHelper.*;
 
 public class TermAPI implements ILuaAPI
 {
@@ -242,9 +242,9 @@ public class TermAPI implements ILuaAPI
                 }
                 else
                 {
-                    double r = getReal( args, 1 );
-                    double g = getReal( args, 2 );
-                    double b = getReal( args, 3 );
+                    double r = getFiniteDouble( args, 1 );
+                    double g = getFiniteDouble( args, 2 );
+                    double b = getFiniteDouble( args, 3 );
                     setColour( m_terminal, colour, r, g, b );
                 }
                 return null;

src/main/java/dan200/computercraft/core/apis/handles/BinaryReadableHandle.java

@@ -21,8 +21,8 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getInt;
-import static dan200.computercraft.core.apis.ArgumentHelper.optBoolean;
+import static dan200.computercraft.api.lua.ArgumentHelper.getInt;
+import static dan200.computercraft.api.lua.ArgumentHelper.optBoolean;
 
 public class BinaryReadableHandle extends HandleGeneric
 {

src/main/java/dan200/computercraft/core/apis/handles/BinaryWritableHandle.java

@@ -7,9 +7,9 @@
 package dan200.computercraft.core.apis.handles;
 
 import com.google.common.collect.ObjectArrays;
+import dan200.computercraft.api.lua.ArgumentHelper;
 import dan200.computercraft.api.lua.ILuaContext;
 import dan200.computercraft.api.lua.LuaException;
-import dan200.computercraft.core.apis.ArgumentHelper;
 import dan200.computercraft.shared.util.StringUtil;
 
 import javax.annotation.Nonnull;
@@ -73,7 +73,7 @@ public class BinaryWritableHandle extends HandleGeneric
                     }
                     else
                     {
-                        throw ArgumentHelper.badArgument( 0, "string or number", args.length > 0 ? args[0] : null );
+                        throw ArgumentHelper.badArgumentOf( 0, "string or number", args.length > 0 ? args[0] : null );
                     }
                     return null;
                 }

src/main/java/dan200/computercraft/core/apis/handles/EncodedReadableHandle.java

@@ -20,8 +20,8 @@ import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CodingErrorAction;
 import java.nio.charset.StandardCharsets;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.optBoolean;
-import static dan200.computercraft.core.apis.ArgumentHelper.optInt;
+import static dan200.computercraft.api.lua.ArgumentHelper.optBoolean;
+import static dan200.computercraft.api.lua.ArgumentHelper.optInt;
 
 public class EncodedReadableHandle extends HandleGeneric
 {

src/main/java/dan200/computercraft/core/apis/handles/HandleGeneric.java

@@ -16,8 +16,8 @@ import java.io.IOException;
 import java.nio.channels.Channel;
 import java.nio.channels.SeekableByteChannel;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.optLong;
-import static dan200.computercraft.core.apis.ArgumentHelper.optString;
+import static dan200.computercraft.api.lua.ArgumentHelper.optLong;
+import static dan200.computercraft.api.lua.ArgumentHelper.optString;
 
 public abstract class HandleGeneric implements ILuaObject
 {
@@ -47,7 +47,7 @@ public abstract class HandleGeneric implements ILuaObject
     }
 
     /**
-     * Shared implementation for various file handle types
+     * Shared implementation for various file handle types.
      *
      * @param channel The channel to seek in
      * @param args    The Lua arguments to process, like Lua's {@code file:seek}.

src/main/java/dan200/computercraft/core/apis/http/NetworkUtils.java

@@ -99,7 +99,7 @@ public final class NetworkUtils
     }
 
     /**
-     * Checks a host is allowed
+     * Checks a host is allowed.
      *
      * @param host The domain to check against
      * @throws HTTPRequestException If the host is not permitted.

src/main/java/dan200/computercraft/core/apis/http/Resource.java

@@ -20,6 +20,8 @@ import java.util.function.Consumer;
 
 /**
  * A holder for one or more resources, with a lifetime.
+ *
+ * @param <T> The type of this resource. Should be the class extending from {@link Resource}.
  */
 public abstract class Resource<T extends Resource<T>> implements Closeable
 {
@@ -42,8 +44,9 @@ public abstract class Resource<T extends Resource<T>> implements Closeable
     }
 
     /**
-     * Checks if this has been cancelled. If so, it'll clean up any
-     * existing resources and cancel any pending futures.
+     * Checks if this has been cancelled. If so, it'll clean up any existing resources and cancel any pending futures.
+     *
+     * @return Whether this resource has been closed.
      */
     public final boolean checkClosed()
     {
@@ -80,6 +83,7 @@ public abstract class Resource<T extends Resource<T>> implements Closeable
     /**
      * Create a {@link WeakReference} which will close {@code this} when collected.
      *
+     * @param <R>    The object we are wrapping in a reference.
      * @param object The object to reference to
      * @return The weak reference.
      */

src/main/java/dan200/computercraft/core/apis/http/ResourceGroup.java

@@ -14,6 +14,8 @@ import java.util.function.Supplier;
 
 /**
  * A collection of {@link Resource}s, with an upper bound on capacity.
+ *
+ * @param <T> The type of the resource this group manages.
  */
 public class ResourceGroup<T extends Resource<T>>
 {

src/main/java/dan200/computercraft/core/apis/http/ResourceQueue.java

@@ -12,6 +12,8 @@ import java.util.function.Supplier;
 
 /**
  * A {@link ResourceGroup} which will queue items when the group at capacity.
+ *
+ * @param <T> The type of the resource this queue manages.
  */
 public class ResourceQueue<T extends Resource<T>> extends ResourceGroup<T>
 {

src/main/java/dan200/computercraft/core/apis/http/request/HttpRequest.java

@@ -40,7 +40,7 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
- * Represents one or more
+ * Represents an in-progress HTTP request.
  */
 public class HttpRequest extends Resource<HttpRequest>
 {

src/main/java/dan200/computercraft/core/apis/http/request/HttpRequestHandler.java

@@ -226,7 +226,11 @@ public final class HttpRequestHandler extends SimpleChannelInboundHandler<HttpOb
     }
 
     /**
-     * Determine the redirect from this response
+     * Determine the redirect from this response.
+     *
+     * @param status  The status of the HTTP response.
+     * @param headers The headers of the HTTP response.
+     * @return The URI to redirect to, or {@code null} if no redirect should occur.
      */
     private URI getRedirect( HttpResponseStatus status, HttpHeaders headers )
     {

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

@@ -23,7 +23,7 @@ import javax.annotation.Nullable;
 import java.io.Closeable;
 import java.util.Arrays;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.optBoolean;
+import static dan200.computercraft.api.lua.ArgumentHelper.optBoolean;
 import static dan200.computercraft.core.apis.http.websocket.Websocket.CLOSE_EVENT;
 import static dan200.computercraft.core.apis.http.websocket.Websocket.MESSAGE_EVENT;
 

src/main/java/dan200/computercraft/core/computer/ComputerExecutor.java

@@ -56,9 +56,6 @@ final class ComputerExecutor
 {
     private static final int QUEUE_LIMIT = 256;
 
-    private static IMount romMount;
-    private static final Object romMountLock = new Object();
-
     private final Computer computer;
     private final List<ILuaAPI> apis = new ArrayList<>();
     final TimeoutState timeout = new TimeoutState();
@@ -268,7 +265,7 @@ final class ComputerExecutor
     }
 
     /**
-     * Queue an event if the computer is on
+     * Queue an event if the computer is on.
      *
      * @param event The event's name
      * @param args  The event's arguments
@@ -329,16 +326,10 @@ final class ComputerExecutor
 
     private IMount getRomMount()
     {
-        if( romMount != null ) return romMount;
-
-        synchronized( romMountLock )
-        {
-            if( romMount != null ) return romMount;
-            return romMount = computer.getComputerEnvironment().createResourceMount( "computercraft", "lua/rom" );
-        }
+        return computer.getComputerEnvironment().createResourceMount( "computercraft", "lua/rom" );
     }
 
-    IWritableMount getRootMount()
+    private IWritableMount getRootMount()
     {
         if( rootMount == null )
         {

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

@@ -50,7 +50,7 @@ import static dan200.computercraft.core.computer.TimeoutState.TIMEOUT;
 public final class ComputerThread
 {
     /**
-     * How often the computer thread monitor should run, in milliseconds
+     * How often the computer thread monitor should run, in milliseconds.
      *
      * @see Monitor
      */
@@ -83,7 +83,7 @@ public final class ComputerThread
     private static final Object threadLock = new Object();
 
     /**
-     * Whether the computer thread system is currently running
+     * Whether the computer thread system is currently running.
      */
     private static volatile boolean running = false;
 
@@ -105,7 +105,7 @@ public final class ComputerThread
     private static final Condition hasWork = computerLock.newCondition();
 
     /**
-     * Active queues to execute
+     * Active queues to execute.
      */
     private static final TreeSet<ComputerExecutor> computerQueue = new TreeSet<>( ( a, b ) -> {
         if( a == b ) return 0; // Should never happen, but let's be consistent here
@@ -126,7 +126,7 @@ public final class ComputerThread
     private ComputerThread() {}
 
     /**
-     * Start the computer thread
+     * Start the computer thread.
      */
     static void start()
     {
@@ -194,7 +194,7 @@ public final class ComputerThread
     }
 
     /**
-     * Mark a computer as having work, enqueuing it on the thread
+     * Mark a computer as having work, enqueuing it on the thread.
      *
      * You must be holding {@link ComputerExecutor}'s {@code queueLock} when calling this method - it should only
      * be called from {@code enqueue}.
@@ -244,6 +244,8 @@ public final class ComputerThread
      * {@link #minimumVirtualRuntime} based on the current tasks.
      *
      * This is called before queueing tasks, to ensure that {@link #minimumVirtualRuntime} is up-to-date.
+     *
+     * @param current The machine which we updating runtimes from.
      */
     private static void updateRuntimes( @Nullable ComputerExecutor current )
     {
@@ -321,7 +323,7 @@ public final class ComputerThread
     }
 
     /**
-     * The scaled period for a single task
+     * The scaled period for a single task.
      *
      * @return The scaled period for the task
      * @see #DEFAULT_LATENCY
@@ -336,7 +338,7 @@ public final class ComputerThread
     }
 
     /**
-     * Determine if the thread has computers queued up
+     * Determine if the thread has computers queued up.
      *
      * @return If we have work queued up.
      */

src/main/java/dan200/computercraft/core/computer/TimeoutState.java

@@ -36,12 +36,12 @@ import java.util.concurrent.TimeUnit;
 public final class TimeoutState
 {
     /**
-     * The total time a task is allowed to run before aborting in nanoseconds
+     * The total time a task is allowed to run before aborting in nanoseconds.
      */
     static final long TIMEOUT = TimeUnit.MILLISECONDS.toNanos( 7000 );
 
     /**
-     * The time the task is allowed to run after each abort in nanoseconds
+     * The time the task is allowed to run after each abort in nanoseconds.
      */
     static final long ABORT_TIMEOUT = TimeUnit.MILLISECONDS.toNanos( 1500 );
 
@@ -111,6 +111,8 @@ public final class TimeoutState
 
     /**
      * If the machine should be passively aborted.
+     *
+     * @return {@code true} if we should throw a timeout error.
      */
     public boolean isSoftAborted()
     {
@@ -118,7 +120,9 @@ public final class TimeoutState
     }
 
     /**
-     * If the machine should be forcibly aborted.
+     * Determine if the machine should be forcibly aborted.
+     *
+     * @return {@code true} if the machine should be forcibly shut down.
      */
     public boolean isHardAborted()
     {
@@ -146,7 +150,7 @@ public final class TimeoutState
     }
 
     /**
-     * Pauses the cumulative time, to be resumed by {@link #startTimer()}
+     * Pauses the cumulative time, to be resumed by {@link #startTimer()}.
      *
      * @see #nanoCumulative()
      */

src/main/java/dan200/computercraft/core/filesystem/ResourceMount.java

@@ -8,13 +8,16 @@ package dan200.computercraft.core.filesystem;
 
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
+import com.google.common.collect.MapMaker;
 import com.google.common.io.ByteStreams;
+import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.core.apis.handles.ArrayByteChannel;
 import net.minecraft.resources.IReloadableResourceManager;
 import net.minecraft.resources.IResource;
 import net.minecraft.resources.IResourceManager;
 import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.ResourceLocationException;
 import net.minecraftforge.resource.IResourceType;
 import net.minecraftforge.resource.ISelectiveResourceReloadListener;
 
@@ -29,7 +32,7 @@ import java.util.*;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Predicate;
 
-public class ResourceMount implements IMount
+public final class ResourceMount implements IMount
 {
     /**
      * Only cache files smaller than 1MiB.
@@ -55,6 +58,13 @@ public class ResourceMount implements IMount
         .<FileEntry, byte[]>weigher( ( k, v ) -> v.length )
         .build();
 
+    private static final MapMaker CACHE_TEMPLATE = new MapMaker().weakValues().concurrencyLevel( 1 );
+
+    /**
+     * Maintain a cache of currently loaded resource mounts. This cache is invalidated when currentManager changes.
+     */
+    private static final Map<IReloadableResourceManager, Map<ResourceLocation, ResourceMount>> MOUNT_CACHE = new WeakHashMap<>( 2 );
+
     private final String namespace;
     private final String subPath;
     private final IReloadableResourceManager manager;
@@ -62,7 +72,26 @@ public class ResourceMount implements IMount
     @Nullable
     private FileEntry root;
 
-    public ResourceMount( String namespace, String subPath, IReloadableResourceManager manager )
+    public static ResourceMount get( String namespace, String subPath, IReloadableResourceManager manager )
+    {
+        Map<ResourceLocation, ResourceMount> cache;
+
+        synchronized( MOUNT_CACHE )
+        {
+            cache = MOUNT_CACHE.get( manager );
+            if( cache == null ) MOUNT_CACHE.put( manager, cache = CACHE_TEMPLATE.makeMap() );
+        }
+
+        ResourceLocation path = new ResourceLocation( namespace, subPath );
+        synchronized( cache )
+        {
+            ResourceMount mount = cache.get( path );
+            if( mount == null ) cache.put( path, mount = new ResourceMount( namespace, subPath, manager ) );
+            return mount;
+        }
+    }
+
+    private ResourceMount( String namespace, String subPath, IReloadableResourceManager manager )
     {
         this.namespace = namespace;
         this.subPath = subPath;
@@ -119,7 +148,17 @@ public class ResourceMount implements IMount
             FileEntry nextEntry = lastEntry.children.get( part );
             if( nextEntry == null )
             {
-                lastEntry.children.put( part, nextEntry = new FileEntry( new ResourceLocation( namespace, subPath + "/" + path ) ) );
+                ResourceLocation childPath;
+                try
+                {
+                    childPath = new ResourceLocation( namespace, subPath + "/" + path );
+                }
+                catch( ResourceLocationException e )
+                {
+                    ComputerCraft.log.warn( "Cannot create resource location for {} ({})", part, e.getMessage() );
+                    return;
+                }
+                lastEntry.children.put( part, nextEntry = new FileEntry( childPath ) );
             }
 
             lastEntry = nextEntry;

src/main/java/dan200/computercraft/core/lua/MachineResult.java

@@ -38,7 +38,7 @@ public final class MachineResult
     public static final MachineResult TIMEOUT = new MachineResult( true, false, TimeoutState.ABORT_MESSAGE );
 
     /**
-     * An error with no user-friendly error message
+     * An error with no user-friendly error message.
      */
     public static final MachineResult GENERIC_ERROR = new MachineResult( true, false, null );
 

src/main/java/dan200/computercraft/core/terminal/Terminal.java

@@ -314,6 +314,9 @@ public class Terminal
     }
 
     /**
+     * Determine whether this terminal has changed.
+     *
+     * @return If this terminal is dirty.
      * @deprecated All {@code *Changed()} methods are deprecated: one should pass in a callback
      * instead.
      */

src/main/java/dan200/computercraft/shared/TurtleUpgrades.java

@@ -11,92 +11,168 @@ import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.util.InventoryUtil;
 import net.minecraft.item.ItemStack;
-import net.minecraftforge.fml.ModContainer;
 import net.minecraftforge.fml.ModLoadingContext;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.*;
+import java.util.stream.Stream;
 
 public final class TurtleUpgrades
 {
+    private static class Wrapper
+    {
+        final ITurtleUpgrade upgrade;
+        final String id;
+        final String modId;
+        boolean enabled;
+
+        Wrapper( ITurtleUpgrade upgrade )
+        {
+            this.upgrade = upgrade;
+            this.id = upgrade.getUpgradeID().toString();
+            this.modId = ModLoadingContext.get().getActiveNamespace();
+            this.enabled = true;
+        }
+    }
+
+    private static ITurtleUpgrade[] vanilla;
+
     private static final Map<String, ITurtleUpgrade> upgrades = new HashMap<>();
-    private static final IdentityHashMap<ITurtleUpgrade, String> upgradeOwners = new IdentityHashMap<>();
+    private static final IdentityHashMap<ITurtleUpgrade, Wrapper> wrappers = new IdentityHashMap<>();
+    private static boolean needsRebuild;
 
     private TurtleUpgrades() {}
 
     public static void register( @Nonnull ITurtleUpgrade upgrade )
     {
         Objects.requireNonNull( upgrade, "upgrade cannot be null" );
+        rebuild();
 
-        String id = upgrade.getUpgradeID().toString();
+        Wrapper wrapper = new Wrapper( upgrade );
+        String id = wrapper.id;
         ITurtleUpgrade existing = upgrades.get( id );
         if( existing != null )
         {
-            throw new IllegalStateException( "Error registering '" + upgrade.getUnlocalisedAdjective() + " Turle'. UpgradeID '" + id + "' is already registered by '" + existing.getUnlocalisedAdjective() + " Turtle'" );
+            throw new IllegalStateException( "Error registering '" + upgrade.getUnlocalisedAdjective() + " Turtle'. Upgrade ID '" + id + "' is already registered by '" + existing.getUnlocalisedAdjective() + " Turtle'" );
         }
 
         upgrades.put( id, upgrade );
-
-        ModContainer mc = ModLoadingContext.get().getActiveContainer();
-        if( mc != null && mc.getModId() != null ) upgradeOwners.put( upgrade, mc.getModId() );
+        wrappers.put( upgrade, wrapper );
     }
 
-
+    @Nullable
     public static ITurtleUpgrade get( String id )
     {
+        rebuild();
         return upgrades.get( id );
     }
 
+    @Nullable
+    public static String getOwner( @Nonnull ITurtleUpgrade upgrade )
+    {
+        Wrapper wrapper = wrappers.get( upgrade );
+        return wrapper != null ? wrapper.modId : null;
+    }
+
     public static ITurtleUpgrade get( @Nonnull ItemStack stack )
     {
         if( stack.isEmpty() ) return null;
 
-        for( ITurtleUpgrade upgrade : upgrades.values() )
+        for( Wrapper wrapper : wrappers.values() )
         {
-            ItemStack craftingStack = upgrade.getCraftingItem();
+            if( !wrapper.enabled ) continue;
+
+            ItemStack craftingStack = wrapper.upgrade.getCraftingItem();
             if( !craftingStack.isEmpty() && InventoryUtil.areItemsSimilar( stack, craftingStack ) )
             {
-                return upgrade;
+                return wrapper.upgrade;
             }
         }
 
         return null;
     }
 
-    public static Iterable<ITurtleUpgrade> getVanillaUpgrades()
+    public static Stream<ITurtleUpgrade> getVanillaUpgrades()
     {
-        List<ITurtleUpgrade> vanilla = new ArrayList<>();
+        if( vanilla == null )
+        {
+            vanilla = new ITurtleUpgrade[] {
+                // ComputerCraft upgrades
+                ComputerCraft.TurtleUpgrades.wirelessModemNormal,
+                ComputerCraft.TurtleUpgrades.wirelessModemAdvanced,
+                ComputerCraft.TurtleUpgrades.speaker,
 
+                // Vanilla Minecraft upgrades
+                ComputerCraft.TurtleUpgrades.diamondPickaxe,
+                ComputerCraft.TurtleUpgrades.diamondAxe,
+                ComputerCraft.TurtleUpgrades.diamondSword,
+                ComputerCraft.TurtleUpgrades.diamondShovel,
+                ComputerCraft.TurtleUpgrades.diamondHoe,
+                ComputerCraft.TurtleUpgrades.craftingTable,
+            };
+        }
 
-        // ComputerCraft upgrades
-        vanilla.add( ComputerCraft.TurtleUpgrades.wirelessModemNormal );
-        vanilla.add( ComputerCraft.TurtleUpgrades.wirelessModemAdvanced );
-        vanilla.add( ComputerCraft.TurtleUpgrades.speaker );
-
-        // Vanilla Minecraft upgrades
-        vanilla.add( ComputerCraft.TurtleUpgrades.diamondPickaxe );
-        vanilla.add( ComputerCraft.TurtleUpgrades.diamondAxe );
-        vanilla.add( ComputerCraft.TurtleUpgrades.diamondSword );
-        vanilla.add( ComputerCraft.TurtleUpgrades.diamondShovel );
-        vanilla.add( ComputerCraft.TurtleUpgrades.diamondHoe );
-        vanilla.add( ComputerCraft.TurtleUpgrades.craftingTable );
-        return vanilla;
+        return Arrays.stream( vanilla ).filter( x -> x != null && wrappers.get( x ).enabled );
     }
 
-    @Nullable
-    public static String getOwner( @Nonnull ITurtleUpgrade upgrade )
+    public static Stream<ITurtleUpgrade> getUpgrades()
     {
-        return upgradeOwners.get( upgrade );
-    }
-
-    public static Iterable<ITurtleUpgrade> getUpgrades()
-    {
-        return Collections.unmodifiableCollection( upgrades.values() );
+        return wrappers.values().stream().filter( x -> x.enabled ).map( x -> x.upgrade );
     }
 
     public static boolean suitableForFamily( ComputerFamily family, ITurtleUpgrade upgrade )
     {
         return true;
     }
+
+    /**
+     * Rebuild the cache of turtle upgrades. This is done before querying the cache or registering new upgrades.
+     */
+    private static void rebuild()
+    {
+        if( !needsRebuild ) return;
+
+        upgrades.clear();
+        for( Wrapper wrapper : wrappers.values() )
+        {
+            if( !wrapper.enabled ) continue;
+
+            ITurtleUpgrade existing = upgrades.get( wrapper.id );
+            if( existing != null )
+            {
+                ComputerCraft.log.error( "Error registering '" + wrapper.upgrade.getUnlocalisedAdjective() + " Turtle'." +
+                    " Upgrade ID '" + wrapper.id + "' is already registered by '" + existing.getUnlocalisedAdjective() + " Turtle'" );
+                continue;
+            }
+
+            upgrades.put( wrapper.id, wrapper.upgrade );
+        }
+
+        needsRebuild = false;
+    }
+
+    public static void enable( ITurtleUpgrade upgrade )
+    {
+        Wrapper wrapper = wrappers.get( upgrade );
+        if( wrapper.enabled ) return;
+
+        wrapper.enabled = true;
+        needsRebuild = true;
+    }
+
+    public static void disable( ITurtleUpgrade upgrade )
+    {
+        Wrapper wrapper = wrappers.get( upgrade );
+        if( !wrapper.enabled ) return;
+
+        wrapper.enabled = false;
+        upgrades.remove( wrapper.id );
+    }
+
+    public static void remove( ITurtleUpgrade upgrade )
+    {
+        wrappers.remove( upgrade );
+        needsRebuild = true;
+    }
 }

src/main/java/dan200/computercraft/shared/command/builder/ArgCommand.java

@@ -11,7 +11,10 @@ import com.mojang.brigadier.context.CommandContext;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 
 /**
- * A {@link Command} which accepts an argument
+ * A {@link Command} which accepts an argument.
+ *
+ * @param <S> The command source we consume.
+ * @param <T> The argument given to this command when executed.
  */
 @FunctionalInterface
 public interface ArgCommand<S, T>

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

@@ -25,8 +25,10 @@ import static dan200.computercraft.shared.command.Exceptions.ARGUMENT_EXPECTED;
 import static dan200.computercraft.shared.command.builder.HelpingArgumentBuilder.literal;
 
 /**
- * An alternative way of building command nodes, so one does not have to nest
+ * An alternative way of building command nodes, so one does not have to nest.
  * {@link ArgumentBuilder#then(CommandNode)}s.
+ *
+ * @param <S> The command source we consume.
  */
 public class CommandBuilder<S> implements CommandNodeBuilder<S, Command<S>>
 {

src/main/java/dan200/computercraft/shared/command/builder/CommandNodeBuilder.java

@@ -10,6 +10,9 @@ import com.mojang.brigadier.tree.CommandNode;
 
 /**
  * A builder which generates a {@link CommandNode} from the provided action.
+ *
+ * @param <S> The command source we consume.
+ * @param <T> The type of action to execute when this command is run.
  */
 @FunctionalInterface
 public interface CommandNodeBuilder<S, T>

src/main/java/dan200/computercraft/shared/command/text/ChatHelpers.java

@@ -12,7 +12,7 @@ import net.minecraft.util.text.event.ClickEvent;
 import net.minecraft.util.text.event.HoverEvent;
 
 /**
- * Various helpers for building chat messages
+ * Various helpers for building chat messages.
  */
 public final class ChatHelpers
 {

src/main/java/dan200/computercraft/shared/command/text/TableBuilder.java

@@ -107,7 +107,7 @@ public class TableBuilder
     }
 
     /**
-     * Trim this table to a given height
+     * Trim this table to a given height.
      *
      * @param height The desired height.
      */

src/main/java/dan200/computercraft/shared/command/text/TableFormatter.java

@@ -22,7 +22,7 @@ public interface TableFormatter
     ITextComponent HEADER = coloured( "=", TextFormatting.GRAY );
 
     /**
-     * Get additional padding for the component
+     * Get additional padding for the component.
      *
      * @param component The component to pad
      * @param width     The desired width for the component
@@ -32,7 +32,7 @@ public interface TableFormatter
     ITextComponent getPadding( ITextComponent component, int width );
 
     /**
-     * Get the minimum padding between each column
+     * Get the minimum padding between each column.
      *
      * @return The minimum padding.
      */

src/main/java/dan200/computercraft/shared/common/ContainerHeldItem.java

@@ -8,7 +8,6 @@ package dan200.computercraft.shared.common;
 
 import dan200.computercraft.shared.network.container.ContainerData;
 import dan200.computercraft.shared.network.container.HeldItemContainerData;
-import dan200.computercraft.shared.util.InventoryUtil;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.inventory.container.Container;
@@ -33,7 +32,7 @@ public class ContainerHeldItem extends Container
         super( type, id );
 
         this.hand = hand;
-        stack = InventoryUtil.copyItem( player.getHeldItem( hand ) );
+        stack = player.getHeldItem( hand ).copy();
     }
 
     private static ContainerHeldItem createPrintout( int id, PlayerInventory inventory, HeldItemContainerData data )

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

@@ -32,8 +32,8 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getInt;
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getInt;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
 
 public class CommandAPI implements ILuaAPI
 {
@@ -85,7 +85,7 @@ public class CommandAPI implements ILuaAPI
         {
             receiver.clearOutput();
             int result = commandManager.handleCommand( m_computer.getSource(), command );
-            return new Object[] { result > 0, receiver.copyOutput() };
+            return new Object[] { result > 0, receiver.copyOutput(), result };
         }
         catch( Throwable t )
         {
@@ -194,7 +194,7 @@ public class CommandAPI implements ILuaAPI
                     );
                     if( !World.isValid( min ) || !World.isValid( max ) )
                     {
-                        throw new LuaException( "Co-ordinates out or range" );
+                        throw new LuaException( "Co-ordinates out of range" );
                     }
                     if( (max.getX() - min.getX() + 1) * (max.getY() - min.getY() + 1) * (max.getZ() - min.getZ() + 1) > 4096 )
                     {
@@ -233,7 +233,7 @@ public class CommandAPI implements ILuaAPI
                     }
                     else
                     {
-                        throw new LuaException( "co-ordinates out or range" );
+                        throw new LuaException( "Co-ordinates out of range" );
                     }
                 } );
             }

src/main/java/dan200/computercraft/shared/computer/blocks/TileComputerBase.java

@@ -230,7 +230,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     }
 
     /**
-     * Gets the redstone input for an adjacent block
+     * Gets the redstone input for an adjacent block.
      *
      * @param world The world we exist in
      * @param pos   The position of the neighbour

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

@@ -7,7 +7,7 @@
 package dan200.computercraft.shared.computer.core;
 
 /**
- * Receives some input and forwards it to a computer
+ * Receives some input and forwards it to a computer.
  *
  * @see InputState
  * @see IComputer

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

@@ -311,13 +311,13 @@ public class ServerComputer extends ServerTerminal implements IComputer, IComput
     @Override
     public double getTimeOfDay()
     {
-        return (m_world.getGameTime() + 6000) % 24000 / 1000.0;
+        return (m_world.getDayTime() + 6000) % 24000 / 1000.0;
     }
 
     @Override
     public int getDay()
     {
-        return (int) ((m_world.getGameTime() + 6000) / 24000) + 1;
+        return (int) ((m_world.getDayTime() + 6000) / 24000) + 1;
     }
 
     @Override

src/main/java/dan200/computercraft/shared/integration/charset/BundledCapabilityProvider.java

@@ -1,89 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.shared.integration.charset;
-
-import dan200.computercraft.shared.common.TileGeneric;
-import net.minecraft.util.Direction;
-import net.minecraftforge.common.capabilities.Capability;
-import net.minecraftforge.common.capabilities.ICapabilityProvider;
-import pl.asie.charset.api.wires.IBundledEmitter;
-import pl.asie.charset.api.wires.IBundledReceiver;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-import static dan200.computercraft.shared.integration.charset.IntegrationCharset.CAPABILITY_EMITTER;
-import static dan200.computercraft.shared.integration.charset.IntegrationCharset.CAPABILITY_RECEIVER;
-
-final class BundledCapabilityProvider implements ICapabilityProvider
-{
-    private final TileGeneric tile;
-    private IBundledReceiver receiver;
-    private IBundledEmitter[] emitters;
-
-    BundledCapabilityProvider( TileGeneric tile )
-    {
-        this.tile = tile;
-    }
-
-    @Override
-    public boolean hasCapability( @Nonnull Capability<?> capability, @Nullable Direction side )
-    {
-        return capability == CAPABILITY_EMITTER || capability == CAPABILITY_RECEIVER;
-    }
-
-    @Nullable
-    @Override
-    public <T> T getCapability( @Nonnull Capability<T> capability, @Nullable Direction side )
-    {
-        if( capability == CAPABILITY_RECEIVER )
-        {
-            IBundledReceiver receiver = this.receiver;
-            if( receiver == null )
-            {
-                receiver = this.receiver = () -> tile.onNeighbourChange( tile.getPos().offset( side ) );
-            }
-
-            return CAPABILITY_RECEIVER.cast( receiver );
-        }
-        else if( capability == CAPABILITY_EMITTER )
-        {
-            IBundledEmitter[] emitters = this.emitters;
-            if( emitters == null ) emitters = this.emitters = new IBundledEmitter[7];
-
-            int index = side == null ? 6 : side.getIndex();
-            IBundledEmitter emitter = emitters[index];
-            if( emitter == null )
-            {
-                if( side == null )
-                {
-                    emitter = emitters[index] = () -> {
-                        int flags = 0;
-                        for( Direction facing : Direction.VALUES ) flags |= tile.getBundledRedstoneOutput( facing );
-                        return toBytes( flags );
-                    };
-                }
-                else
-                {
-                    emitter = emitters[index] = () -> toBytes( tile.getBundledRedstoneOutput( side ) );
-                }
-            }
-
-            return CAPABILITY_EMITTER.cast( emitter );
-        }
-        else
-        {
-            return null;
-        }
-    }
-
-    private static byte[] toBytes( int flag )
-    {
-        byte[] channels = new byte[16];
-        for( int i = 0; i < 16; i++ ) channels[i] = (flag & (1 << i)) == 0 ? (byte) 0 : 15;
-        return channels;
-    }
-}

src/main/java/dan200/computercraft/shared/integration/charset/BundledRedstoneProvider.java

@@ -1,33 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.shared.integration.charset;
-
-import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
-import net.minecraft.tileentity.TileEntity;
-import net.minecraft.util.Direction;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.World;
-
-import javax.annotation.Nonnull;
-
-import static dan200.computercraft.shared.integration.charset.IntegrationCharset.CAPABILITY_EMITTER;
-
-public class BundledRedstoneProvider implements IBundledRedstoneProvider
-{
-    @Override
-    public int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull Direction side )
-    {
-        TileEntity tile = world.getTileEntity( pos );
-        if( tile == null || !tile.hasCapability( CAPABILITY_EMITTER, side ) ) return -1;
-
-        byte[] signal = tile.getCapability( CAPABILITY_EMITTER, side ).getBundledSignal();
-        if( signal == null ) return -1;
-
-        int flag = 0;
-        for( int i = 0; i < signal.length; i++ ) flag |= signal[i] > 0 ? 1 << i : 0;
-        return flag;
-    }
-}

src/main/java/dan200/computercraft/shared/integration/charset/IntegrationCharset.java

@@ -1,52 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.shared.integration.charset;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.api.ComputerCraftAPI;
-import dan200.computercraft.shared.common.TileGeneric;
-import net.minecraft.tileentity.TileEntity;
-import net.minecraft.util.ResourceLocation;
-import net.minecraftforge.common.MinecraftForge;
-import net.minecraftforge.common.capabilities.Capability;
-import net.minecraftforge.common.capabilities.CapabilityInject;
-import net.minecraftforge.event.AttachCapabilitiesEvent;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-import pl.asie.charset.api.wires.IBundledEmitter;
-import pl.asie.charset.api.wires.IBundledReceiver;
-
-public final class IntegrationCharset
-{
-    private static final ResourceLocation CAPABILITY_KEY = new ResourceLocation( ComputerCraft.MOD_ID, "charset" );
-
-    @CapabilityInject( IBundledEmitter.class )
-    static Capability<IBundledEmitter> CAPABILITY_EMITTER = null;
-
-    @CapabilityInject( IBundledReceiver.class )
-    static Capability<IBundledReceiver> CAPABILITY_RECEIVER = null;
-
-    private IntegrationCharset()
-    {
-    }
-
-    public static void register()
-    {
-        if( CAPABILITY_EMITTER == null || CAPABILITY_RECEIVER == null ) return;
-
-        MinecraftForge.EVENT_BUS.register( IntegrationCharset.class );
-        ComputerCraftAPI.registerBundledRedstoneProvider( new BundledRedstoneProvider() );
-    }
-
-    @SubscribeEvent
-    public static void attachGenericCapabilities( AttachCapabilitiesEvent<TileEntity> event )
-    {
-        TileEntity tile = event.getObject();
-        if( tile instanceof TileGeneric )
-        {
-            event.addCapability( CAPABILITY_KEY, new BundledCapabilityProvider( (TileGeneric) tile ) );
-        }
-    }
-}

src/main/java/dan200/computercraft/shared/integration/crafttweaker/TrackingLogger.java

@@ -0,0 +1,40 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.integration.crafttweaker;
+
+import com.blamejared.crafttweaker.api.logger.ILogger;
+
+/**
+ * Logger which tracks if it has any messages.
+ */
+public final class TrackingLogger
+{
+    private final ILogger logger;
+    private boolean ok = true;
+
+    public TrackingLogger( ILogger logger )
+    {
+        this.logger = logger;
+    }
+
+    public boolean isOk()
+    {
+        return ok;
+    }
+
+    public void warning( String message )
+    {
+        ok = false;
+        logger.warning( message );
+    }
+
+    public void error( String message )
+    {
+        ok = false;
+        logger.error( message );
+    }
+}

src/main/java/dan200/computercraft/shared/integration/crafttweaker/TurtleTweaker.java

@@ -0,0 +1,72 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.integration.crafttweaker;
+
+import com.blamejared.crafttweaker.api.CraftTweakerAPI;
+import com.blamejared.crafttweaker.api.annotations.ZenRegister;
+import com.blamejared.crafttweaker.api.item.IItemStack;
+import dan200.computercraft.shared.integration.crafttweaker.actions.AddTurtleTool;
+import dan200.computercraft.shared.integration.crafttweaker.actions.RemoveTurtleUpgradeByItem;
+import dan200.computercraft.shared.integration.crafttweaker.actions.RemoveTurtleUpgradeByName;
+import org.openzen.zencode.java.ZenCodeType;
+
+@ZenRegister
+@ZenCodeType.Name( "dan200.computercraft.turtle" )
+public class TurtleTweaker
+{
+    /**
+     * Remove a turtle upgrade with the given id.
+     *
+     * @param upgrade The ID of the to remove
+     */
+    @ZenCodeType.Method
+    public static void removeUpgrade( String upgrade )
+    {
+        CraftTweakerAPI.apply( new RemoveTurtleUpgradeByName( upgrade ) );
+    }
+
+    /**
+     * Remove a turtle upgrade crafted with the given item stack".
+     *
+     * @param stack The stack with which the upgrade is crafted.
+     */
+    @ZenCodeType.Method
+    public static void removeUpgrade( IItemStack stack )
+    {
+        CraftTweakerAPI.apply( new RemoveTurtleUpgradeByItem( stack.getInternal() ) );
+    }
+
+    /**
+     * Add a new turtle tool with the given id, which crafts and acts using the given stack.
+     *
+     * @param id    The new upgrade's ID
+     * @param stack The stack used for crafting the upgrade and used by the turtle as a tool.
+     */
+    @ZenCodeType.Method
+    public static void addTool( String id, IItemStack stack )
+    {
+        addTool( id, stack, stack, "tool" );
+    }
+
+    @ZenCodeType.Method
+    public static void addTool( String id, IItemStack craftingStack, IItemStack toolStack )
+    {
+        addTool( id, craftingStack, toolStack, "tool" );
+    }
+
+    @ZenCodeType.Method
+    public static void addTool( String id, IItemStack stack, String kind )
+    {
+        addTool( id, stack, stack, kind );
+    }
+
+    @ZenCodeType.Method
+    public static void addTool( String id, IItemStack craftingStack, IItemStack toolStack, String kind )
+    {
+        CraftTweakerAPI.apply( new AddTurtleTool( id, craftingStack.getInternal(), toolStack.getInternal(), kind ) );
+    }
+}

src/main/java/dan200/computercraft/shared/integration/crafttweaker/actions/AddTurtleTool.java

@@ -0,0 +1,127 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.integration.crafttweaker.actions;
+
+import com.blamejared.crafttweaker.api.actions.IUndoableAction;
+import com.blamejared.crafttweaker.api.logger.ILogger;
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.shared.TurtleUpgrades;
+import dan200.computercraft.shared.integration.crafttweaker.TrackingLogger;
+import dan200.computercraft.shared.turtle.upgrades.*;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.fml.LogicalSide;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Register a new turtle tool.
+ */
+public class AddTurtleTool implements IUndoableAction
+{
+    private interface Factory
+    {
+        TurtleTool create( ResourceLocation location, ItemStack craftItem, ItemStack toolItem );
+    }
+
+    private static final Map<String, Factory> kinds = new HashMap<>();
+
+    static
+    {
+        kinds.put( "tool", TurtleTool::new );
+        kinds.put( "axe", TurtleAxe::new );
+        kinds.put( "hoe", TurtleHoe::new );
+        kinds.put( "shovel", TurtleShovel::new );
+        kinds.put( "sword", TurtleSword::new );
+    }
+
+    private final String id;
+    private final ItemStack craftItem;
+    private final ItemStack toolItem;
+    private final String kind;
+
+    private ITurtleUpgrade upgrade;
+
+    public AddTurtleTool( String id, ItemStack craftItem, ItemStack toolItem, String kind )
+    {
+        this.id = id;
+        this.craftItem = craftItem;
+        this.toolItem = toolItem;
+        this.kind = kind;
+    }
+
+    @Override
+    public void apply()
+    {
+        ITurtleUpgrade upgrade = this.upgrade;
+        if( upgrade == null )
+        {
+            Factory factory = kinds.get( kind );
+            if( factory == null )
+            {
+                ComputerCraft.log.error( "Unknown turtle upgrade kind '{}' (this should have been rejected by verify!)", kind );
+                return;
+            }
+
+            upgrade = this.upgrade = factory.create( new ResourceLocation( id ), craftItem, toolItem );
+        }
+
+        try
+        {
+            TurtleUpgrades.register( upgrade );
+        }
+        catch( RuntimeException e )
+        {
+            ComputerCraft.log.error( "Registration of turtle tool failed", e );
+        }
+    }
+
+    @Override
+    public String describe()
+    {
+        return String.format( "Add new turtle %s '%s' (crafted with '%s', uses a '%s')", kind, id, craftItem, toolItem );
+    }
+
+    @Override
+    public void undo()
+    {
+        if( upgrade != null ) TurtleUpgrades.remove( upgrade );
+    }
+
+    @Override
+    public String describeUndo()
+    {
+        return String.format( "Removing turtle upgrade %s.", id );
+    }
+
+    public boolean validate( ILogger logger )
+    {
+        TrackingLogger trackLog = new TrackingLogger( logger );
+
+        if( craftItem.isEmpty() ) trackLog.warning( "Crafting item stack is empty." );
+
+        if( craftItem.hasTag() && !craftItem.getTag().isEmpty() ) trackLog.warning( "Crafting item has NBT." );
+        if( toolItem.isEmpty() ) trackLog.error( "Tool item stack is empty." );
+
+        if( !kinds.containsKey( kind ) ) trackLog.error( String.format( "Unknown kind '%s'.", kind ) );
+
+        if( TurtleUpgrades.get( id ) != null )
+        {
+            trackLog.error( String.format( "An upgrade with the same name ('%s') has already been registered.", id ) );
+        }
+
+        return trackLog.isOk();
+    }
+
+    @Override
+    public boolean shouldApplyOn( LogicalSide side )
+    {
+        return true;
+    }
+}

src/main/java/dan200/computercraft/shared/integration/crafttweaker/actions/RemoveTurtleUpgradeByItem.java

@@ -0,0 +1,71 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.integration.crafttweaker.actions;
+
+import com.blamejared.crafttweaker.api.actions.IUndoableAction;
+import com.blamejared.crafttweaker.api.logger.ILogger;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.shared.TurtleUpgrades;
+import net.minecraft.item.ItemStack;
+import net.minecraftforge.fml.LogicalSide;
+
+/**
+ * Removes a turtle upgrade crafted with the given stack.
+ */
+public class RemoveTurtleUpgradeByItem implements IUndoableAction
+{
+    private final ItemStack stack;
+    private ITurtleUpgrade upgrade;
+
+    public RemoveTurtleUpgradeByItem( ItemStack stack )
+    {
+        this.stack = stack;
+    }
+
+    @Override
+    public void apply()
+    {
+        ITurtleUpgrade upgrade = this.upgrade = TurtleUpgrades.get( stack );
+        if( upgrade != null ) TurtleUpgrades.disable( upgrade );
+    }
+
+    @Override
+    public String describe()
+    {
+        return String.format( "Remove turtle upgrades crafted with '%s'", stack );
+    }
+
+    @Override
+    public void undo()
+    {
+        if( this.upgrade != null ) TurtleUpgrades.enable( upgrade );
+    }
+
+    @Override
+    public String describeUndo()
+    {
+        return String.format( "Adding back turtle upgrades crafted with '%s'", stack );
+    }
+
+    @Override
+    public boolean validate( ILogger logger )
+    {
+        if( TurtleUpgrades.get( stack ) == null )
+        {
+            logger.error( String.format( "Unknown turtle upgrade crafted with '%s'.", stack ) );
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean shouldApplyOn( LogicalSide side )
+    {
+        return true;
+    }
+}

src/main/java/dan200/computercraft/shared/integration/crafttweaker/actions/RemoveTurtleUpgradeByName.java

@@ -0,0 +1,70 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.integration.crafttweaker.actions;
+
+import com.blamejared.crafttweaker.api.actions.IUndoableAction;
+import com.blamejared.crafttweaker.api.logger.ILogger;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.shared.TurtleUpgrades;
+import net.minecraftforge.fml.LogicalSide;
+
+/**
+ * Removes a turtle upgrade with the given id.
+ */
+public class RemoveTurtleUpgradeByName implements IUndoableAction
+{
+    private final String id;
+    private ITurtleUpgrade upgrade;
+
+    public RemoveTurtleUpgradeByName( String id )
+    {
+        this.id = id;
+    }
+
+    @Override
+    public void apply()
+    {
+        ITurtleUpgrade upgrade = this.upgrade = TurtleUpgrades.get( id );
+        if( upgrade != null ) TurtleUpgrades.disable( upgrade );
+    }
+
+    @Override
+    public String describe()
+    {
+        return String.format( "Remove turtle upgrade '%s'", id );
+    }
+
+    @Override
+    public void undo()
+    {
+        if( this.upgrade != null ) TurtleUpgrades.enable( upgrade );
+    }
+
+    @Override
+    public String describeUndo()
+    {
+        return String.format( "Adding back turtle upgrade '%s'", id );
+    }
+
+    @Override
+    public boolean validate( ILogger logger )
+    {
+        if( TurtleUpgrades.get( id ) == null )
+        {
+            logger.error( String.format( "Unknown turtle upgrade '%s'.", id ) );
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public boolean shouldApplyOn( LogicalSide side )
+    {
+        return true;
+    }
+}

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

@@ -35,7 +35,6 @@ import net.minecraft.util.ResourceLocation;
 
 import javax.annotation.Nonnull;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 import static dan200.computercraft.shared.integration.jei.RecipeResolver.MAIN_FAMILIES;
@@ -77,12 +76,10 @@ public class JEIComputerCraft implements IModPlugin
         List<ItemStack> upgradeItems = new ArrayList<>();
         for( ComputerFamily family : MAIN_FAMILIES )
         {
-            for( ITurtleUpgrade upgrade : TurtleUpgrades.getUpgrades() )
-            {
-                if( !TurtleUpgrades.suitableForFamily( family, upgrade ) ) continue;
-
-                upgradeItems.add( TurtleItemFactory.create( -1, null, -1, family, null, upgrade, 0, null ) );
-            }
+            TurtleUpgrades.getUpgrades()
+                .filter( x -> TurtleUpgrades.suitableForFamily( family, x ) )
+                .map( x -> TurtleItemFactory.create( -1, null, -1, family, null, x, 0, null ) )
+                .forEach( upgradeItems::add );
 
             for( IPocketUpgrade upgrade : PocketUpgrades.getUpgrades() )
             {
@@ -92,10 +89,6 @@ public class JEIComputerCraft implements IModPlugin
 
         runtime.getIngredientManager().addIngredientsAtRuntime( VanillaTypes.ITEM, upgradeItems );
 
-        // Hide treasure disks
-        runtime.getIngredientManager().removeIngredientsAtRuntime( VanillaTypes.ITEM,
-            Collections.singletonList( new ItemStack( ComputerCraft.Items.treasureDisk ) ) );
-
         // Hide all upgrade recipes
         IRecipeCategory<?> category = (IRecipeCategory<?>) registry.getRecipeCategory( VanillaRecipeCategoryUid.CRAFTING );
         if( category != null )
@@ -114,7 +107,7 @@ public class JEIComputerCraft implements IModPlugin
     }
 
     /**
-     * Distinguishes turtles by upgrades and family
+     * Distinguishes turtles by upgrades and family.
      */
     private static final ISubtypeInterpreter turtleSubtype = stack -> {
         Item item = stack.getItem();
@@ -134,7 +127,7 @@ public class JEIComputerCraft implements IModPlugin
     };
 
     /**
-     * Distinguishes pocket computers by upgrade and family
+     * Distinguishes pocket computers by upgrade and family.
      */
     private static final ISubtypeInterpreter pocketSubtype = stack -> {
         Item item = stack.getItem();
@@ -150,7 +143,7 @@ public class JEIComputerCraft implements IModPlugin
     };
 
     /**
-     * Distinguishes disks by colour
+     * Distinguishes disks by colour.
      */
     private static final ISubtypeInterpreter diskSubtype = stack -> {
         Item item = stack.getItem();

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

@@ -53,15 +53,14 @@ class RecipeResolver implements IRecipeManagerPlugin
         if( initialised ) return;
         initialised = true;
 
-        for( ITurtleUpgrade upgrade : TurtleUpgrades.getUpgrades() )
-        {
+        TurtleUpgrades.getUpgrades().forEach( upgrade -> {
             ItemStack stack = upgrade.getCraftingItem();
-            if( stack.isEmpty() ) continue;
+            if( stack.isEmpty() ) return;
 
             UpgradeInfo info = new UpgradeInfo( stack, upgrade );
             upgradeItemLookup.computeIfAbsent( stack.getItem(), k -> new ArrayList<>( 1 ) ).add( info );
             turtleUpgrades.add( info );
-        }
+        } );
 
         for( IPocketUpgrade upgrade : PocketUpgrades.getUpgrades() )
         {

src/main/java/dan200/computercraft/shared/integration/mcmp/MCMPHooks.java

@@ -1,49 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.shared.integration.mcmp;
-
-import mcmultipart.MCMultiPart;
-import mcmultipart.api.item.ItemBlockMultipart;
-import net.minecraft.block.BlockState;
-import net.minecraft.entity.player.PlayerEntity;
-import net.minecraft.item.BlockItem;
-import net.minecraft.item.ItemStack;
-import net.minecraft.util.ActionResultType;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.World;
-import net.minecraftforge.fml.common.Loader;
-
-import javax.annotation.Nonnull;
-
-public final class MCMPHooks
-{
-    private MCMPHooks()
-    {
-    }
-
-    public static ActionResultType onItemUse( BlockItem itemBlock, PlayerEntity player, World world, @Nonnull BlockPos pos, @Nonnull Hand hand, @Nonnull Direction facing, float hitX, float hitY, float hitZ )
-    {
-        if( !Loader.isModLoaded( MCMultiPart.MODID ) ) return ActionResultType.PASS;
-
-        return ItemBlockMultipart.place(
-            player, world, pos, hand, facing, hitX, hitY, hitZ, itemBlock,
-            itemBlock.getBlock()::getStateForPlacement,
-            MCMPIntegration.multipartMap.get( itemBlock.getBlock() ),
-
-            (
-                ItemStack stack, PlayerEntity thisPlayer, World thisWorld, BlockPos thisPos, Direction thisFacing,
-                float thisX, float thisY, float thisZ, BlockState thisState
-            ) ->
-                thisPlayer.canPlayerEdit( thisPos, thisFacing, stack ) &&
-                    thisWorld.getBlockState( thisPos ).getBlock().isReplaceable( thisWorld, thisPos ) &&
-                    itemBlock.getBlock().canPlaceBlockAt( thisWorld, thisPos ) &&
-                    itemBlock.getBlock().canPlaceBlockOnSide( thisWorld, thisPos, thisFacing ) &&
-                    itemBlock.placeBlockAt( stack, thisPlayer, thisWorld, thisPos, thisFacing, thisX, thisY, thisZ, thisState ),
-            ItemBlockMultipart::placePartAt
-        );
-    }
-}

src/main/java/dan200/computercraft/shared/integration/mcmp/MCMPIntegration.java

@@ -1,127 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.shared.integration.mcmp;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.api.ComputerCraftAPI;
-import dan200.computercraft.api.peripheral.IPeripheral;
-import dan200.computercraft.api.peripheral.IPeripheralTile;
-import dan200.computercraft.shared.peripheral.common.TilePeripheralBase;
-import dan200.computercraft.shared.peripheral.modem.wireless.TileAdvancedModem;
-import dan200.computercraft.shared.peripheral.modem.wireless.TileWirelessModem;
-import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
-import mcmultipart.api.addon.IMCMPAddon;
-import mcmultipart.api.addon.MCMPAddon;
-import mcmultipart.api.container.IMultipartContainer;
-import mcmultipart.api.multipart.IMultipart;
-import mcmultipart.api.multipart.IMultipartRegistry;
-import mcmultipart.api.multipart.IMultipartTile;
-import mcmultipart.api.ref.MCMPCapabilities;
-import mcmultipart.api.slot.EnumFaceSlot;
-import net.minecraft.block.Block;
-import net.minecraft.tileentity.TileEntity;
-import net.minecraft.util.Direction;
-import net.minecraft.util.ResourceLocation;
-import net.minecraftforge.common.MinecraftForge;
-import net.minecraftforge.common.capabilities.Capability;
-import net.minecraftforge.common.capabilities.ICapabilityProvider;
-import net.minecraftforge.event.AttachCapabilitiesEvent;
-import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-import java.util.HashMap;
-import java.util.Map;
-
-@MCMPAddon
-public class MCMPIntegration implements IMCMPAddon
-{
-    private static final ResourceLocation CAPABILITY_KEY = new ResourceLocation( ComputerCraft.MOD_ID, "mcmultipart" );
-
-    static final Map<Block, IMultipart> multipartMap = new HashMap<>();
-
-    private static void register( IMultipartRegistry registry, Block block, IMultipart multipart )
-    {
-        registry.registerPartWrapper( block, multipart );
-        multipartMap.put( block, multipart );
-    }
-
-    @Override
-    public void registerParts( IMultipartRegistry registry )
-    {
-        // Setup all parts
-        register( registry, ComputerCraft.Blocks.peripheral, new PartPeripheral() );
-        register( registry, ComputerCraft.Blocks.advancedModem, new PartAdvancedModem() );
-
-        // Subscribe to capability events
-        MinecraftForge.EVENT_BUS.register( MCMPIntegration.class );
-
-        // Register a peripheral provider
-        ComputerCraftAPI.registerPeripheralProvider( ( world, pos, side ) ->
-        {
-            TileEntity tile = world.getTileEntity( pos );
-            if( tile == null || !tile.hasCapability( MCMPCapabilities.MULTIPART_CONTAINER, null ) ) return null;
-            IMultipartContainer container = tile.getCapability( MCMPCapabilities.MULTIPART_CONTAINER, null );
-            if( container == null ) return null;
-
-            IMultipartTile multipart = container.getPartTile( EnumFaceSlot.fromFace( side ) ).orElse( null );
-            if( multipart == null ) return null;
-            if( multipart instanceof IPeripheral ) return (IPeripheral) multipart;
-            if( multipart instanceof IPeripheralTile ) return ((IPeripheralTile) multipart).getPeripheral( side );
-
-            TileEntity underlying = multipart.getTileEntity();
-            if( underlying instanceof IPeripheral ) return (IPeripheral) underlying;
-            if( underlying instanceof IPeripheralTile ) return ((IPeripheralTile) underlying).getPeripheral( side );
-
-            return null;
-        } );
-    }
-
-    @SubscribeEvent
-    public static void attach( AttachCapabilitiesEvent<TileEntity> event )
-    {
-        TileEntity tile = event.getObject();
-        if( tile instanceof TileAdvancedModem || tile instanceof TileWirelessModem
-            || tile instanceof TilePeripheralBase || tile instanceof TileMonitor )
-        {
-            // We need to attach to modems (obviously), but also any other tile created by BlockPeripheral. Otherwise
-            // IMultipart.convertToMultipartTile will error.
-            event.addCapability( CAPABILITY_KEY, new BasicMultipart( tile ) );
-        }
-    }
-
-    private static final class BasicMultipart implements ICapabilityProvider
-    {
-        private final TileEntity tile;
-        private IMultipartTile wrapped;
-
-        private BasicMultipart( TileEntity tile )
-        {
-            this.tile = tile;
-        }
-
-        @Override
-        public boolean hasCapability( @Nonnull Capability<?> capability, @Nullable Direction facing )
-        {
-            return capability == MCMPCapabilities.MULTIPART_TILE;
-        }
-
-        @Nullable
-        @Override
-        public <T> T getCapability( @Nonnull Capability<T> capability, @Nullable Direction facing )
-        {
-            if( capability == MCMPCapabilities.MULTIPART_TILE )
-            {
-                IMultipartTile wrapped = this.wrapped;
-                if( wrapped == null ) wrapped = this.wrapped = IMultipartTile.wrap( tile );
-                return MCMPCapabilities.MULTIPART_TILE.cast( wrapped );
-            }
-
-            return null;
-        }
-    }
-}

src/main/java/dan200/computercraft/shared/integration/mcmp/PartAdvancedModem.java

@@ -1,41 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.shared.integration.mcmp;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.peripheral.modem.wireless.BlockAdvancedModem;
-import mcmultipart.api.multipart.IMultipart;
-import mcmultipart.api.slot.EnumFaceSlot;
-import mcmultipart.api.slot.IPartSlot;
-import net.minecraft.block.Block;
-import net.minecraft.block.BlockState;
-import net.minecraft.entity.LivingEntity;
-import net.minecraft.util.Direction;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.IBlockAccess;
-import net.minecraft.world.World;
-
-public class PartAdvancedModem implements IMultipart
-{
-    @Override
-    public IPartSlot getSlotForPlacement( World world, BlockPos pos, BlockState state, Direction facing, float hitX, float hitY, float hitZ, LivingEntity placer )
-    {
-        return EnumFaceSlot.fromFace( state.getValue( BlockAdvancedModem.FACING ) );
-    }
-
-    @Override
-    public IPartSlot getSlotFromWorld( IBlockAccess world, BlockPos pos, BlockState state )
-    {
-        return EnumFaceSlot.fromFace( state.getValue( BlockAdvancedModem.FACING ) );
-    }
-
-    @Override
-    public Block getBlock()
-    {
-        return ComputerCraft.Blocks.advancedModem;
-    }
-}

src/main/java/dan200/computercraft/shared/integration/mcmp/PartPeripheral.java

@@ -1,67 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-
-package dan200.computercraft.shared.integration.mcmp;
-
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.shared.peripheral.common.BlockPeripheral;
-import dan200.computercraft.shared.peripheral.common.BlockPeripheralVariant;
-import mcmultipart.api.multipart.IMultipart;
-import mcmultipart.api.slot.EnumCenterSlot;
-import mcmultipart.api.slot.EnumFaceSlot;
-import mcmultipart.api.slot.IPartSlot;
-import net.minecraft.block.Block;
-import net.minecraft.block.BlockState;
-import net.minecraft.entity.LivingEntity;
-import net.minecraft.util.Direction;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.IBlockAccess;
-import net.minecraft.world.World;
-
-import javax.annotation.Nonnull;
-
-public class PartPeripheral implements IMultipart
-{
-    @Override
-    public IPartSlot getSlotForPlacement( World world, BlockPos pos, BlockState state, Direction facing, float hitX, float hitY, float hitZ, LivingEntity placer )
-    {
-        return getSlot( state );
-    }
-
-    @Override
-    public IPartSlot getSlotFromWorld( IBlockAccess world, BlockPos pos, BlockState state )
-    {
-        return getSlot( state );
-    }
-
-    @Nonnull
-    private static IPartSlot getSlot( BlockState state )
-    {
-        BlockPeripheralVariant type = state.getValue( BlockPeripheral.VARIANT );
-        if( type == BlockPeripheralVariant.WirelessModemUpOn || type == BlockPeripheralVariant.WirelessModemUpOff )
-        {
-            return EnumFaceSlot.UP;
-        }
-        else if( type == BlockPeripheralVariant.WirelessModemDownOn || type == BlockPeripheralVariant.WirelessModemDownOff )
-        {
-            return EnumFaceSlot.DOWN;
-        }
-        else if( type == BlockPeripheralVariant.WirelessModemOff || type == BlockPeripheralVariant.WirelessModemOn )
-        {
-            return EnumFaceSlot.fromFace( state.getValue( BlockPeripheral.FACING ) );
-        }
-        else
-        {
-            return EnumCenterSlot.CENTER;
-        }
-    }
-
-    @Override
-    public Block getBlock()
-    {
-        return ComputerCraft.Blocks.peripheral;
-    }
-}

src/main/java/dan200/computercraft/shared/media/items/RecordMedia.java

@@ -20,7 +20,7 @@ import net.minecraftforge.fml.common.ObfuscationReflectionHelper.UnableToFindFie
 import javax.annotation.Nonnull;
 
 /**
- * An implementation of IMedia for ItemRecord's
+ * An implementation of IMedia for ItemRecords.
  */
 public final class RecordMedia implements IMedia
 {

src/main/java/dan200/computercraft/shared/network/NetworkHandler.java

@@ -90,6 +90,7 @@ public final class NetworkHandler
      * /**
      * Register packet, and a thread-unsafe handler for it.
      *
+     * @param <T>     The type of the packet to send.
      * @param id      The identifier for this packet type
      * @param factory The factory for this type of packet.
      */
@@ -106,6 +107,8 @@ public final class NetworkHandler
      * /**
      * Register packet, and a thread-unsafe handler for it.
      *
+     * @param <T>     The type of the packet to send.
+     * @param type    The class of the type of packet to send.
      * @param id      The identifier for this packet type
      * @param decoder The factory for this type of packet.
      */

src/main/java/dan200/computercraft/shared/network/container/HeldItemContainerData.java

@@ -13,7 +13,7 @@ import net.minecraft.util.Hand;
 import javax.annotation.Nonnull;
 
 /**
- * Opens a printout GUI based on the currently held item
+ * Opens a printout GUI based on the currently held item.
  *
  * @see ContainerHeldItem
  * @see dan200.computercraft.shared.media.items.ItemPrintout

src/main/java/dan200/computercraft/shared/peripheral/commandblock/CommandBlockPeripheral.java

@@ -14,7 +14,7 @@ import net.minecraft.tileentity.CommandBlockTileEntity;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
 
 public class CommandBlockPeripheral implements IPeripheral
 {

src/main/java/dan200/computercraft/shared/peripheral/diskdrive/DiskDrivePeripheral.java

@@ -18,7 +18,7 @@ import net.minecraft.item.ItemStack;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.optString;
+import static dan200.computercraft.api.lua.ArgumentHelper.optString;
 
 class DiskDrivePeripheral implements IPeripheral
 {

src/main/java/dan200/computercraft/shared/peripheral/modem/ModemPeripheral.java

@@ -21,7 +21,7 @@ import javax.annotation.Nonnull;
 import java.util.HashSet;
 import java.util.Set;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getInt;
+import static dan200.computercraft.api.lua.ArgumentHelper.getInt;
 
 public abstract class ModemPeripheral implements IPeripheral, IPacketSender, IPacketReceiver
 {

src/main/java/dan200/computercraft/shared/peripheral/modem/wired/BlockCable.java

@@ -210,7 +210,7 @@ public class BlockCable extends BlockGeneric implements IWaterLoggable
 
         BlockPos offsetPos = pos.offset( facing );
         BlockState offsetState = world.getBlockState( offsetPos );
-        return Block.hasSolidSide( offsetState, world, offsetPos, facing.getOpposite() );
+        return hasSolidSide( offsetState, world, offsetPos, facing.getOpposite() );
     }
 
     @Nullable

src/main/java/dan200/computercraft/shared/peripheral/modem/wired/TileCable.java

@@ -201,8 +201,7 @@ public class TileCable extends TileGeneric implements IPeripheralTile
     public void onNeighbourChange( @Nonnull BlockPos neighbour )
     {
         Direction dir = getDirection();
-        if( neighbour.equals( getPos().offset( dir ) ) && hasModem()
-            && getBlockState().isValidPosition( world, pos ) )
+        if( neighbour.equals( getPos().offset( dir ) ) && hasModem() && !getBlockState().isValidPosition( getWorld(), getPos() ) )
         {
             if( hasCable() )
             {

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

@@ -23,7 +23,7 @@ import java.util.Collections;
 import java.util.Map;
 
 /**
- * Represents a local peripheral exposed on the wired network
+ * Represents a local peripheral exposed on the wired network.
  *
  * This is responsible for getting the peripheral in world, tracking id and type and determining whether
  * it has changed.
@@ -39,7 +39,7 @@ public final class WiredModemLocalPeripheral
     private IPeripheral peripheral;
 
     /**
-     * Attach a new peripheral from the world
+     * Attach a new peripheral from the world.
      *
      * @param world     The world to search in
      * @param origin    The position to search from
@@ -76,7 +76,7 @@ public final class WiredModemLocalPeripheral
     }
 
     /**
-     * Detach the current peripheral
+     * Detach the current peripheral.
      *
      * @return Whether the peripheral changed
      */

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

@@ -28,7 +28,7 @@ import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
 
 public abstract class WiredModemPeripheral extends ModemPeripheral implements IWiredSender
 {

src/main/java/dan200/computercraft/shared/peripheral/monitor/BlockMonitor.java

@@ -49,9 +49,18 @@ public class BlockMonitor extends BlockGeneric
     @Override
     public BlockRenderLayer getRenderLayer()
     {
+        // We use the CUTOUT layer, as otherwise monitor rendering will cause flickering.
         return BlockRenderLayer.CUTOUT;
     }
 
+    @Override
+    @Deprecated
+    public boolean isSolid( BlockState state )
+    {
+        // We override isSolid, as our overriding of getRenderLayer means that it would otherwise return false.
+        return true;
+    }
+
     @Override
     protected void fillStateContainer( StateContainer.Builder<Block, BlockState> builder )
     {

src/main/java/dan200/computercraft/shared/peripheral/monitor/MonitorPeripheral.java

@@ -17,7 +17,7 @@ import org.apache.commons.lang3.ArrayUtils;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.*;
+import static dan200.computercraft.api.lua.ArgumentHelper.*;
 
 public class MonitorPeripheral implements IPeripheral
 {
@@ -123,7 +123,7 @@ public class MonitorPeripheral implements IPeripheral
             case 8:
             {
                 // setTextScale
-                int scale = (int) (getReal( args, 0 ) * 2.0);
+                int scale = (int) (getFiniteDouble( args, 0 ) * 2.0);
                 if( scale < 1 || scale > 10 )
                 {
                     throw new LuaException( "Expected number in range 0.5-5" );
@@ -184,9 +184,9 @@ public class MonitorPeripheral implements IPeripheral
                 }
                 else
                 {
-                    double r = getReal( args, 1 );
-                    double g = getReal( args, 2 );
-                    double b = getReal( args, 3 );
+                    double r = getFiniteDouble( args, 1 );
+                    double g = getFiniteDouble( args, 2 );
+                    double b = getFiniteDouble( args, 3 );
                     TermAPI.setColour( terminal, colour, r, g, b );
                 }
                 return null;

src/main/java/dan200/computercraft/shared/peripheral/printer/PrinterPeripheral.java

@@ -15,8 +15,8 @@ import dan200.computercraft.shared.util.StringUtil;
 
 import javax.annotation.Nonnull;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getInt;
-import static dan200.computercraft.core.apis.ArgumentHelper.optString;
+import static dan200.computercraft.api.lua.ArgumentHelper.getInt;
+import static dan200.computercraft.api.lua.ArgumentHelper.optString;
 
 public class PrinterPeripheral implements IPeripheral
 {

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

@@ -23,8 +23,8 @@ import net.minecraft.world.World;
 import javax.annotation.Nonnull;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import static dan200.computercraft.core.apis.ArgumentHelper.getString;
-import static dan200.computercraft.core.apis.ArgumentHelper.optReal;
+import static dan200.computercraft.api.lua.ArgumentHelper.getString;
+import static dan200.computercraft.api.lua.ArgumentHelper.optFiniteDouble;
 
 public abstract class SpeakerPeripheral implements IPeripheral
 {
@@ -72,8 +72,8 @@ public abstract class SpeakerPeripheral implements IPeripheral
             case 0: // playSound
             {
                 String name = getString( args, 0 );
-                float volume = (float) optReal( args, 1, 1.0 );
-                float pitch = (float) optReal( args, 2, 1.0 );
+                float volume = (float) optFiniteDouble( args, 1, 1.0 );
+                float pitch = (float) optFiniteDouble( args, 2, 1.0 );
 
                 ResourceLocation identifier;
                 try
@@ -100,8 +100,8 @@ public abstract class SpeakerPeripheral implements IPeripheral
     private synchronized Object[] playNote( Object[] arguments, ILuaContext context ) throws LuaException
     {
         String name = getString( arguments, 0 );
-        float volume = (float) optReal( arguments, 1, 1.0 );
-        float pitch = (float) optReal( arguments, 2, 1.0 );
+        float volume = (float) optFiniteDouble( arguments, 1, 1.0 );
+        float pitch = (float) optFiniteDouble( arguments, 2, 1.0 );
 
         NoteBlockInstrument instrument = null;
         for( NoteBlockInstrument testInstrument : NoteBlockInstrument.values() )

src/main/java/dan200/computercraft/shared/proxy/ComputerCraftProxyCommon.java

@@ -67,8 +67,6 @@ public final class ComputerCraftProxyCommon
             PlayerCreativeLootCondition.class,
             PlayerCreativeLootCondition.INSTANCE
         ) );
-
-        // if( Loader.isModLoaded( ModCharset.MODID ) ) IntegrationCharset.register();
     }
 
     private static void registerProviders()