Correctly implement mouse movement within read

Note to self: if you're going to modify the rom, make sure you test on a
computer which doesn't overwrite the rom with something else.

.github/workflows/main-ci.yml

@@ -0,0 +1,18 @@
+name: Build
+
+on: [push, pull_request]
+
+jobs:
+  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

.gitignore

@@ -15,3 +15,9 @@
 .idea
 .gradle
 *.DS_Store
+
+.classpath
+.project
+.settings/
+bin/
+*.launch

.luacheckrc

@@ -17,7 +17,8 @@ ignore = {
 -- are largely unsupported.
 include_files = {
     'src/main/resources/assets/computercraft/lua/rom',
-    'src/main/resources/assets/computercraft/lua/bios.lua'
+    'src/main/resources/assets/computercraft/lua/bios.lua',
+    'src/test/resources/test-rom',
 }
 
 files['src/main/resources/assets/computercraft/lua/bios.lua'] = {

.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:
-    - oraclejdk8

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](https://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

@@ -5,7 +5,7 @@ buildscript {
         jcenter()
         maven {
             name = "forge"
-            url = "http://files.minecraftforge.net/maven"
+            url = "https://files.minecraftforge.net/maven"
         }
     }
     dependencies {
@@ -17,7 +17,9 @@ buildscript {
 }
 
 plugins {
-    id 'com.matthewprenger.cursegradle' version '1.2.0'
+    id "checkstyle"
+    id "com.github.hierynomus.license" version "0.15.0"
+    id "com.matthewprenger.cursegradle" version "1.3.0"
     id "com.github.breadmoirai.github-release" version "2.2.4"
 }
 
@@ -43,7 +45,7 @@ minecraft {
 repositories {
     maven {
         name "JEI"
-        url "http://dvs1.progwml6.com/files/maven"
+        url "https://dvs1.progwml6.com/files/maven"
     }
     maven {
         name "SquidDev"
@@ -55,7 +57,7 @@ repositories {
     }
     maven {
         name "Amadornes"
-        url "http://maven.amadornes.com/"
+        url "https://maven.amadornes.com/"
     }
 }
 
@@ -66,6 +68,8 @@ configurations {
 }
 
 dependencies {
+    checkstyle "com.puppycrawl.tools:checkstyle:8.25"
+
     deobfProvided "mezz.jei:jei_1.12.2:4.15.0.269:api"
     deobfProvided "pl.asie:Charset-Lib:0.5.4.6"
     deobfProvided "MCMultiPart2:MCMultiPart:2.5.3"
@@ -74,12 +78,14 @@ dependencies {
 
     shade 'org.squiddev:Cobalt:0.5.0-SNAPSHOT'
 
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.1.0'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.1.0'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.2'
 
     deployerJars "org.apache.maven.wagon:wagon-ssh:3.0.0"
 }
 
+// Compile tasks
+
 javadoc {
     include "dan200/computercraft/api/**/*.java"
 }
@@ -98,12 +104,22 @@ jar {
     from configurations.shade.collect { it.isDirectory() ? it : zipTree(it) }
 }
 
+[compileJava, compileTestJava].forEach {
+    it.configure {
+        options.compilerArgs << "-Xlint" << "-Xlint:-processing" << "-Werror"
+    }
+}
+
+
+
 import java.nio.charset.StandardCharsets
 import java.nio.file.*
 import java.util.zip.*
 
 import com.google.gson.GsonBuilder
 import com.google.gson.JsonElement
+import com.hierynomus.gradle.license.tasks.LicenseCheck
+import com.hierynomus.gradle.license.tasks.LicenseFormat
 import org.ajoberstar.grgit.Grgit
 import proguard.gradle.ProGuardTask
 
@@ -199,6 +215,7 @@ task compressJson(dependsOn: extractAnnotationsJar) {
         // Copy over all files in the current jar to the new one, running json files from GSON. As pretty printing
         // is turned off, they should be minified.
         new ZipFile(jarPath).withCloseable { inJar ->
+            tempPath.getParentFile().mkdirs()
             new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(tempPath))).withCloseable { outJar ->
                 inJar.entries().each { entry ->
                     if(entry.directory) {
@@ -226,6 +243,56 @@ task compressJson(dependsOn: extractAnnotationsJar) {
 
 assemble.dependsOn compressJson
 
+// Check tasks
+
+test {
+    useJUnitPlatform()
+    testLogging {
+        events "skipped", "failed"
+    }
+}
+
+license {
+    mapping("java", "SLASHSTAR_STYLE")
+    strictCheck true
+
+    ext.year = Calendar.getInstance().get(Calendar.YEAR)
+}
+
+[licenseMain, licenseFormatMain].forEach {
+    it.configure {
+        include("**/*.java")
+        exclude("dan200/computercraft/api/**")
+        header rootProject.file('config/license/main.txt')
+    }
+}
+
+[licenseTest, licenseFormatTest].forEach {
+    it.configure {
+        include("**/*.java")
+        header rootProject.file('config/license/main.txt')
+    }
+}
+
+gradle.projectsEvaluated {
+    tasks.withType(LicenseFormat) {
+        outputs.upToDateWhen { false }
+    }
+}
+
+
+task licenseAPI(type: LicenseCheck);
+task licenseFormatAPI(type: LicenseFormat);
+[licenseAPI, licenseFormatAPI].forEach {
+    it.configure {
+        source = sourceSets.main.java
+        include("dan200/computercraft/api/**")
+        header rootProject.file('config/license/api.txt')
+    }
+}
+
+// Upload tasks
+
 task checkRelease {
     group "upload"
     description "Verifies that everything is ready for a release"
@@ -264,7 +331,7 @@ task checkRelease {
         if (!ok) throw new IllegalStateException("Could not check release")
     }
 }
-
+check.dependsOn checkRelease
 
 curseforge {
     apiKey = project.hasProperty('curseForgeApiKey') ? project.curseForgeApiKey : ''
@@ -336,7 +403,9 @@ 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}"
@@ -357,18 +426,5 @@ task uploadAll(dependsOn: uploadTasks) {
     description "Uploads to all repositories (Maven, Curse, GitHub release)"
 }
 
-test {
-    useJUnitPlatform()
-    testLogging {
-        events "passed", "skipped", "failed"
-    }
-}
-
-gradle.projectsEvaluated {
-    tasks.withType(JavaCompile) {
-        options.compilerArgs << "-Xlint" << "-Xlint:-processing" << "-Werror"
-    }
-}
-
 runClient.outputs.upToDateWhen { false }
 runServer.outputs.upToDateWhen { false }

config/checkstyle/checkstyle.xml

@@ -0,0 +1,169 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE module PUBLIC
+    "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+    "https://checkstyle.org/dtds/configuration_1_3.dtd">
+<module name="Checker">
+    <property name="tabWidth" value="4"/>
+    <property name="charset" value="UTF-8" />
+
+    <module name="SuppressionFilter">
+        <property name="file" value="config/checkstyle/suppressions.xml" />
+    </module>
+
+    <module name="TreeWalker">
+        <!-- Annotations -->
+        <module name="AnnotationLocation" />
+        <module name="AnnotationUseStyle" />
+        <module name="MissingDeprecated" />
+        <module name="MissingOverride" />
+
+        <!-- Blocks -->
+        <module name="EmptyBlock" />
+        <module name="EmptyCatchBlock">
+            <property name="exceptionVariableName" value="ignored" />
+        </module>
+        <module name="LeftCurly">
+            <property name="option" value="nl" />
+            <!-- The defaults, minus lambdas. -->
+            <property name="tokens" value="ANNOTATION_DEF,CLASS_DEF,CTOR_DEF,ENUM_CONSTANT_DEF,ENUM_DEF,INTERFACE_DEF,LITERAL_CASE,LITERAL_CATCH,LITERAL_DEFAULT,LITERAL_DO,LITERAL_ELSE,LITERAL_FINALLY,LITERAL_FOR,LITERAL_IF,LITERAL_SWITCH,LITERAL_SYNCHRONIZED,LITERAL_TRY,LITERAL_WHILE,METHOD_DEF,OBJBLOCK,STATIC_INIT" />
+        </module>
+        <module name="NeedBraces">
+            <property name="allowSingleLineStatement" value="true"/>
+        </module>
+        <module name="RightCurly">
+            <property name="option" value="alone" />
+        </module>
+
+        <!-- Class design. As if we've ever followed good practice here. -->
+        <module name="FinalClass" />
+        <module name="InterfaceIsType" />
+        <module name="MutableException" />
+        <module name="OneTopLevelClass" />
+
+        <!-- Coding -->
+        <module name="ArrayTrailingComma" />
+        <module name="EqualsHashCode" />
+        <!-- FallThrough does not handle unreachable code well -->
+        <module name="IllegalInstantiation" />
+        <module name="IllegalThrows" />
+        <module name="ModifiedControlVariable" />
+        <module name="NoClone" />
+        <module name="NoFinalizer" />
+        <module name="OneStatementPerLine" />
+        <module name="PackageDeclaration" />
+        <module name="SimplifyBooleanExpression" />
+        <module name="SimplifyBooleanReturn" />
+        <module name="StringLiteralEquality" />
+        <module name="UnnecessaryParentheses" />
+        <module name="UnnecessarySemicolonAfterTypeMemberDeclaration" />
+        <module name="UnnecessarySemicolonInTryWithResources" />
+        <module name="UnnecessarySemicolonInEnumeration" />
+
+        <!-- Imports -->
+        <module name="CustomImportOrder" />
+        <module name="IllegalImport" />
+        <module name="RedundantImport" />
+        <module name="UnusedImports" />
+
+        <!-- Javadoc -->
+        <!-- TODO: Missing* checks for the dan200.computercraft.api package? -->
+        <module name="AtclauseOrder" />
+        <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" />
+        <module name="CommentsIndentation" />
+        <module name="Indentation" />
+        <module name="OuterTypeFilename" />
+
+        <!-- Modifiers -->
+        <module name="ModifierOrder" />
+        <module name="RedundantModifier" />
+
+        <!-- Naming -->
+        <module name="ClassTypeParameterName" />
+        <module name="InterfaceTypeParameterName" />
+        <module name="LambdaParameterName" />
+        <module name="LocalFinalVariableName" />
+        <module name="LocalVariableName" />
+        <!-- Allow an optional m_ on private members -->
+        <module name="MemberName">
+            <property name="applyToPrivate" value="false" />
+            <property name="applyToPackage" value="false" />
+        </module>
+        <module name="MemberName">
+            <property name="format" value="^(m_)?[a-z][a-zA-Z0-9]*$" />
+            <property name="applyToPrivate" value="true" />
+            <property name="applyToPackage" value="true" />
+        </module>
+        <module name="MethodName" />
+        <module name="MethodTypeParameterName" />
+        <module name="PackageName">
+            <property name="format" value="^dan200\.computercraf(\.[a-z][a-z0-9]*)*" />
+        </module>
+        <module name="ParameterName" />
+        <module name="StaticVariableName">
+            <property name="format" value="^[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z]+)?$" />
+            <property name="applyToPrivate" value="false" />
+        </module>
+        <module name="StaticVariableName">
+            <property name="format" value="^(s_)?[a-z][a-zA-Z0-9]*|CAPABILITY(_[A-Z]+)?$" />
+            <property name="applyToPrivate" value="true" />
+        </module>
+        <module name="TypeName" />
+
+        <!-- Whitespace -->
+        <module name="EmptyForInitializerPad"/>
+        <module name="EmptyForIteratorPad">
+            <property name="option" value="space"/>
+        </module>
+        <module name="GenericWhitespace" />
+        <module name="MethodParamPad" />
+        <module name="NoLineWrap" />
+        <module name="NoWhitespaceAfter">
+            <property name="tokens" value="AT,INC,DEC,UNARY_MINUS,UNARY_PLUS,BNOT,LNOT,DOT,ARRAY_DECLARATOR,INDEX_OP" />
+        </module>
+        <module name="NoWhitespaceBefore" />
+        <!-- TODO: Decide on an OperatorWrap style. -->
+        <module name="ParenPad">
+            <property name="option" value="space" />
+            <property name="tokens" value="ANNOTATION,ANNOTATION_FIELD_DEF,CTOR_CALL,CTOR_DEF,ENUM_CONSTANT_DEF,LITERAL_CATCH,LITERAL_DO,LITERAL_FOR,LITERAL_IF,LITERAL_NEW,LITERAL_SWITCH,LITERAL_SYNCHRONIZED,LITERAL_WHILE,METHOD_CALL,METHOD_DEF,RESOURCE_SPECIFICATION,SUPER_CTOR_CALL,LAMBDA" />
+        </module>
+        <module name="ParenPad">
+            <property name="option" value="nospace" />
+            <property name="tokens" value="DOT,EXPR,QUESTION" />
+        </module>
+        <module name="SeparatorWrap">
+            <property name="option" value="eol" />
+            <property name="tokens" value="COMMA,SEMI,ELLIPSIS,ARRAY_DECLARATOR,RBRACK,METHOD_REF" />
+        </module>
+        <module name="SeparatorWrap">
+            <property name="option" value="nl" />
+            <property name="tokens" value="DOT,AT" />
+        </module>
+        <module name="SingleSpaceSeparator" />
+        <module name="TypecastParenPad" />
+        <module name="WhitespaceAfter">
+            <property name="tokens" value="COMMA" />
+        </module>
+        <module name="WhitespaceAround">
+            <property name="allowEmptyConstructors" value="true" />
+            <property name="ignoreEnhancedForColon" value="false" />
+            <property name="tokens" value="ASSIGN,BAND,BAND_ASSIGN,BOR,BOR_ASSIGN,BSR,BSR_ASSIGN,BXOR,BXOR_ASSIGN,COLON,DIV,DIV_ASSIGN,DO_WHILE,EQUAL,GE,GT,LAMBDA,LAND,LCURLY,LE,LITERAL_RETURN,LOR,LT,MINUS,MINUS_ASSIGN,MOD,MOD_ASSIGN,NOT_EQUAL,PLUS,PLUS_ASSIGN,QUESTION,RCURLY,SL,SLIST,SL_ASSIGN,SR,SR_ASSIGN,STAR,STAR_ASSIGN,LITERAL_ASSERT,TYPE_EXTENSION_AND" />
+        </module>
+    </module>
+
+    <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

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE suppressions PUBLIC
+    "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
+    "https://checkstyle.org/dtds/suppressions_1_2.dtd">
+<suppressions>
+    <!-- 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>

config/license/api.txt

@@ -0,0 +1,3 @@
+This file is part of the public ComputerCraft API - http://www.computercraft.info
+Copyright Daniel Ratcliffe, 2011-${year}. 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.

config/license/main.txt

@@ -0,0 +1,3 @@
+This file is part of ComputerCraft - http://www.computercraft.info
+Copyright Daniel Ratcliffe, 2011-${year}. Do not distribute without permission.
+Send enquiries to dratcliffe@gmail.com

gradle.properties

@@ -1,5 +1,5 @@
 # Mod properties
-mod_version=1.83.1
+mod_version=1.85.2
 
 # Minecraft properties
 mc_version=1.12.2

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

@@ -72,9 +72,7 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.world.IBlockAccess;
 import net.minecraft.world.World;
 import net.minecraftforge.common.DimensionManager;
-import net.minecraftforge.fml.common.FMLCommonHandler;
-import net.minecraftforge.fml.common.Mod;
-import net.minecraftforge.fml.common.SidedProxy;
+import net.minecraftforge.fml.common.*;
 import net.minecraftforge.fml.common.event.*;
 import net.minecraftforge.fml.relauncher.Side;
 import org.apache.logging.log4j.Logger;
@@ -83,9 +81,7 @@ import java.io.*;
 import java.net.MalformedURLException;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.util.ArrayList;
-import java.util.EnumSet;
-import java.util.List;
+import java.util.*;
 import java.util.concurrent.TimeUnit;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
@@ -394,6 +390,27 @@ public class ComputerCraft
         }
     }
 
+    private static void loadFromFile( List<IMount> mounts, File file, String path, boolean allowMissing )
+    {
+        try
+        {
+            if( file.isFile() )
+            {
+                mounts.add( new JarMount( file, path ) );
+            }
+            else
+            {
+                File subResource = new File( file, path );
+                if( subResource.exists() ) mounts.add( new FileMount( subResource, 0 ) );
+            }
+        }
+        catch( IOException | RuntimeException e )
+        {
+            if( allowMissing && e instanceof FileNotFoundException ) return;
+            ComputerCraft.log.error( "Could not load mount '" + path + " 'from '" + file.getName() + "'", e );
+        }
+    }
+
     @Deprecated
     public static IMount createResourceMount( Class<?> modClass, String domain, String subPath )
     {
@@ -413,18 +430,26 @@ public class ComputerCraft
             }
         }
 
-        // Mount from mod jar
+        // Mount from mod jars, preferring the specified one.
         File modJar = getContainingJar( modClass );
+        Set<File> otherMods = new HashSet<>();
+        for( ModContainer container : Loader.instance().getActiveModList() )
+        {
+            File modFile = container.getSource();
+            if( modFile != null && !modFile.equals( modJar ) && modFile.exists() )
+            {
+                otherMods.add( container.getSource() );
+            }
+        }
+
+        for( File file : otherMods )
+        {
+            loadFromFile( mounts, file, subPath, true );
+        }
+
         if( modJar != null )
         {
-            try
-            {
-                mounts.add( new JarMount( modJar, subPath ) );
-            }
-            catch( IOException | RuntimeException e )
-            {
-                ComputerCraft.log.error( "Could not load mount from mod jar", e );
-            }
+            loadFromFile( mounts, modJar, subPath, false );
         }
 
         // Mount from resource packs
@@ -434,28 +459,8 @@ public class ComputerCraft
             String[] resourcePacks = resourcePackDir.list();
             for( String resourcePackName : resourcePacks )
             {
-                try
-                {
-                    File resourcePack = new File( resourcePackDir, resourcePackName );
-                    if( !resourcePack.isDirectory() )
-                    {
-                        // Mount a resource pack from a jar
-                        mounts.add( new JarMount( resourcePack, subPath ) );
-                    }
-                    else
-                    {
-                        // Mount a resource pack from a folder
-                        File subResource = new File( resourcePack, subPath );
-                        if( subResource.exists() ) mounts.add( new FileMount( subResource, 0 ) );
-                    }
-                }
-                catch( FileNotFoundException ignored )
-                {
-                }
-                catch( IOException | RuntimeException e )
-                {
-                    ComputerCraft.log.error( "Could not load resource pack '" + resourcePackName + "'", e );
-                }
+                File resourcePack = new File( resourcePackDir, resourcePackName );
+                loadFromFile( mounts, resourcePack, subPath, true );
             }
         }
 

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

@@ -1,9 +1,8 @@
 /*
- * 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
+ * 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;
 
 import dan200.computercraft.api.turtle.ITurtleUpgrade;

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

@@ -32,8 +32,9 @@ import java.lang.reflect.Method;
 
 /**
  * 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
 {
@@ -269,7 +270,7 @@ 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
@@ -370,7 +371,7 @@ 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
@@ -398,7 +399,7 @@ 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
@@ -438,45 +439,45 @@ public final class ComputerCraftAPI
                 computerCraft_getVersion = findCCMethod( "getVersion", new Class<?>[] {
                 } );
                 computerCraft_createUniqueNumberedSaveDir = findCCMethod( "createUniqueNumberedSaveDir", new Class<?>[] {
-                    World.class, String.class
+                    World.class, String.class,
                 } );
                 computerCraft_createSaveDirMount = findCCMethod( "createSaveDirMount", new Class<?>[] {
-                    World.class, String.class, Long.TYPE
+                    World.class, String.class, Long.TYPE,
                 } );
                 computerCraft_createResourceMount = findCCMethod( "createResourceMount", new Class<?>[] {
-                    Class.class, String.class, String.class
+                    Class.class, String.class, String.class,
                 } );
                 computerCraft_registerPeripheralProvider = findCCMethod( "registerPeripheralProvider", new Class<?>[] {
-                    IPeripheralProvider.class
+                    IPeripheralProvider.class,
                 } );
                 computerCraft_registerTurtleUpgrade = findCCMethod( "registerTurtleUpgrade", new Class<?>[] {
-                    ITurtleUpgrade.class
+                    ITurtleUpgrade.class,
                 } );
                 computerCraft_registerBundledRedstoneProvider = findCCMethod( "registerBundledRedstoneProvider", new Class<?>[] {
-                    IBundledRedstoneProvider.class
+                    IBundledRedstoneProvider.class,
                 } );
                 computerCraft_getDefaultBundledRedstoneOutput = findCCMethod( "getDefaultBundledRedstoneOutput", new Class<?>[] {
-                    World.class, BlockPos.class, EnumFacing.class
+                    World.class, BlockPos.class, EnumFacing.class,
                 } );
                 computerCraft_registerMediaProvider = findCCMethod( "registerMediaProvider", new Class<?>[] {
-                    IMediaProvider.class
+                    IMediaProvider.class,
                 } );
                 computerCraft_registerPermissionProvider = findCCMethod( "registerPermissionProvider", new Class<?>[] {
-                    ITurtlePermissionProvider.class
+                    ITurtlePermissionProvider.class,
                 } );
                 computerCraft_registerPocketUpgrade = findCCMethod( "registerPocketUpgrade", new Class<?>[] {
-                    IPocketUpgrade.class
+                    IPocketUpgrade.class,
                 } );
                 computerCraft_getWirelessNetwork = findCCMethod( "getWirelessNetwork", new Class<?>[] {
                 } );
                 computerCraft_registerAPIFactory = findCCMethod( "registerAPIFactory", new Class<?>[] {
-                    ILuaAPIFactory.class
+                    ILuaAPIFactory.class,
                 } );
                 computerCraft_createWiredNodeForElement = findCCMethod( "createWiredNodeForElement", new Class<?>[] {
-                    IWiredElement.class
+                    IWiredElement.class,
                 } );
                 computerCraft_getWiredElementAt = findCCMethod( "getWiredElementAt", new Class<?>[] {
-                    IBlockAccess.class, BlockPos.class, EnumFacing.class
+                    IBlockAccess.class, BlockPos.class, EnumFacing.class,
                 } );
             }
             catch( Exception e )

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

@@ -0,0 +1,41 @@
+/*
+ * 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.filesystem;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.io.IOException;
+import java.util.Objects;
+
+/**
+ * An {@link IOException} which occurred on a specific file.
+ *
+ * This may be thrown from a {@link IMount} or {@link IWritableMount} to give more information about a failure.
+ */
+public class FileOperationException extends IOException
+{
+    private static final long serialVersionUID = -8809108200853029849L;
+
+    private final String filename;
+
+    public FileOperationException( @Nullable String filename, @Nonnull String message )
+    {
+        super( Objects.requireNonNull( message, "message cannot be null" ) );
+        this.filename = filename;
+    }
+
+    public FileOperationException( String message )
+    {
+        super( Objects.requireNonNull( message, "message cannot be null" ) );
+        this.filename = null;
+    }
+
+    @Nullable
+    public String getFilename()
+    {
+        return filename;
+    }
+}

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.
@@ -90,7 +90,6 @@ public interface IMount
      * @throws IOException If the file does not exist, or could not be opened.
      */
     @Nonnull
-    @SuppressWarnings( "deprecation" )
     default ReadableByteChannel openChannelForRead( @Nonnull String path ) throws IOException
     {
         return Channels.newChannel( openForRead( path ) );

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

@@ -67,7 +67,6 @@ public interface IWritableMount extends IMount
      * @throws IOException If the file could not be opened for writing.
      */
     @Nonnull
-    @SuppressWarnings( "deprecation" )
     default WritableByteChannel openChannelForWrite( @Nonnull String path ) throws IOException
     {
         return Channels.newChannel( openForWrite( path ) );
@@ -94,7 +93,6 @@ public interface IWritableMount extends IMount
      * @throws IOException If the file could not be opened for writing.
      */
     @Nonnull
-    @SuppressWarnings( "deprecation" )
     default WritableByteChannel openChannelForAppend( @Nonnull String path ) throws IOException
     {
         return Channels.newChannel( openForAppend( path ) );

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/peripheral/IWorkMonitor.java

@@ -1,9 +1,8 @@
 /*
- * 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
+ * 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.peripheral;
 
 import javax.annotation.Nonnull;

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

@@ -1,9 +1,8 @@
 /*
- * 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
+ * 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.pocket;
 
 import net.minecraft.item.ItemStack;

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/ITurtleAccess.java

@@ -145,7 +145,9 @@ public interface ITurtleAccess
     GameProfile getOwningPlayer();
 
     /**
-     * Get the inventory of this turtle
+     * Get the inventory of this turtle.
+     *
+     * Note: this inventory should only be accessed and modified on the server thread.
      *
      * @return This turtle's inventory
      * @see #getItemHandler()
@@ -156,6 +158,8 @@ public interface ITurtleAccess
     /**
      * Get the inventory of this turtle as an {@link IItemHandlerModifiable}.
      *
+     * Note: this inventory should only be accessed and modified on the server thread.
+     *
      * @return This turtle's inventory
      * @see #getInventory()
      * @see IItemHandlerModifiable

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

@@ -109,8 +109,8 @@ public interface ITurtleUpgrade
      * Will only be called for Tool turtle. Called when turtle.dig() or turtle.attack() is called
      * by the turtle, and the tool is required to do some work.
      *
-     * Conforming implementations should fire {@link BlockEvent.BreakEvent} and {@link TurtleBlockEvent.Dig}for digging,
-     * {@link AttackEntityEvent} and {@link TurtleAttackEvent} for attacking.
+     * Conforming implementations should fire {@link BlockEvent.BreakEvent} and {@link TurtleBlockEvent.Dig} for
+     * digging, {@link AttackEntityEvent} and {@link TurtleAttackEvent} for attacking.
      *
      * @param turtle    Access to the turtle that the tool resides on.
      * @param side      Which side of the turtle (left or right) the tool resides on.

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.EnumFacing;
 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/TurtleInspectItemEvent.java

@@ -1,9 +1,8 @@
 /*
- * 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
+ * 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.turtle.event;
 
 import dan200.computercraft.api.lua.ILuaContext;

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/api/turtle/event/TurtleRefuelEvent.java

@@ -1,9 +1,8 @@
 /*
- * 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
+ * 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.turtle.event;
 
 import dan200.computercraft.api.turtle.ITurtleAccess;

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

@@ -120,7 +120,7 @@ public class GuiTurtle extends GuiContainer
             int slotX = slot % 4;
             int slotY = slot / 4;
             mc.getTextureManager().bindTexture( advanced ? BACKGROUND_ADVANCED : BACKGROUND_NORMAL );
-            drawTexturedModalRect( guiLeft + m_container.m_turtleInvStartX - 2 + slotX * 18, guiTop + m_container.m_playerInvStartY - 2 + slotY * 18, 0, 217, 24, 24 );
+            drawTexturedModalRect( guiLeft + m_container.turtleInvStartX - 2 + slotX * 18, guiTop + m_container.playerInvStartY - 2 + slotY * 18, 0, 217, 24, 24 );
         }
     }
 

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 ItemRenderer#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 = Side.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 = Side.CLIENT )
 public final class ItemPrintoutRenderer extends ItemMapLikeRenderer

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

@@ -94,7 +94,7 @@ public final class ModelTransformer
         private final Point3f[] before = new Point3f[4];
         private final Point3f[] after = new Point3f[4];
 
-        public NormalAwareTransformer( IVertexConsumer parent, Matrix4f positionMatrix, Matrix4f normalMatrix )
+        NormalAwareTransformer( IVertexConsumer parent, Matrix4f positionMatrix, Matrix4f normalMatrix )
         {
             super( parent );
             this.positionMatrix = positionMatrix;

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

@@ -97,6 +97,8 @@ public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable
     }
 
     /**
+     * Set up the state for rendering block-breaking progress.
+     *
      * @see RenderGlobal#preRenderDamagedBlocks()
      */
     private void preRenderDamagedBlocks()
@@ -115,6 +117,8 @@ public class TileEntityCableRenderer extends TileEntitySpecialRenderer<TileCable
     }
 
     /**
+     * Tear down the state for rendering block-breaking progress.
+     *
      * @see RenderGlobal#postRenderDamagedBlocks()
      */
     private void postRenderDamagedBlocks()

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

@@ -154,7 +154,7 @@ 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
 {
@@ -43,9 +43,7 @@ public class FSAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "fs"
-        };
+        return new String[] { "fs" };
     }
 
     @Override

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
@@ -42,9 +42,7 @@ public class HTTPAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "http"
-        };
+        return new String[] { "http" };
     }
 
     @Override
@@ -83,6 +81,7 @@ public class HTTPAPI implements ILuaAPI
     }
 
     @Override
+    @SuppressWarnings( "resource" )
     public Object[] callMethod( @Nonnull ILuaContext context, int method, @Nonnull Object[] args ) throws LuaException
     {
         switch( method )
@@ -90,12 +89,12 @@ 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 )
                 {
-                    Map<?, ?> options = (Map) args[0];
+                    Map<?, ?> options = (Map<?, ?>) args[0];
                     address = getStringField( options, "url" );
                     postString = optStringField( options, "body", null );
                     headerTable = optTableField( options, "headers", Collections.emptyMap() );
@@ -135,7 +134,6 @@ public class HTTPAPI implements ILuaAPI
                 try
                 {
                     URI uri = HttpRequest.checkUri( address );
-
                     HttpRequest request = new HttpRequest( requests, m_apiEnvironment, address, postString, headers, binary, redirect );
 
                     long requestBody = request.body().readableBytes() + HttpRequest.getHeaderSize( headers );
@@ -174,7 +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/ILuaAPI.java

@@ -10,6 +10,7 @@ package dan200.computercraft.core.apis;
  * This exists purely to ensure binary compatibility.
  *
  * @see dan200.computercraft.api.lua.ILuaAPI
+ * @deprecated Use the version in the public API. Only exists for compatibility with CCEmuX.
  */
 @Deprecated
 public interface ILuaAPI extends dan200.computercraft.api.lua.ILuaAPI

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
 {
@@ -36,9 +36,9 @@ public class OSAPI implements ILuaAPI
 
     private static class Timer
     {
-        public int m_ticksLeft;
+        int m_ticksLeft;
 
-        public Timer( int ticksLeft )
+        Timer( int ticksLeft )
         {
             m_ticksLeft = ticksLeft;
         }
@@ -46,10 +46,10 @@ public class OSAPI implements ILuaAPI
 
     private static class Alarm implements Comparable<Alarm>
     {
-        public final double m_time;
-        public final int m_day;
+        final double m_time;
+        final int m_day;
 
-        public Alarm( double time, int day )
+        Alarm( double time, int day )
         {
             m_time = time;
             m_day = day;
@@ -78,9 +78,7 @@ public class OSAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "os"
-        };
+        return new String[] { "os" };
     }
 
     @Override
@@ -231,7 +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 ) ) );
@@ -241,7 +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" );
@@ -385,9 +383,7 @@ public class OSAPI implements ILuaAPI
                         // Get in-game epoch
                         synchronized( m_alarms )
                         {
-                            return new Object[] {
-                                m_day * 86400000 + (int) (m_time * 3600000.0f)
-                            };
+                            return new Object[] { m_day * 86400000 + (int) (m_time * 3600000.0f) };
                         }
                     default:
                         throw new LuaException( "Unsupported operation" );
@@ -401,7 +397,6 @@ public class OSAPI implements ILuaAPI
                 Instant instant = Instant.ofEpochSecond( time );
                 ZonedDateTime date;
                 ZoneOffset offset;
-                boolean isDst;
                 if( format.startsWith( "!" ) )
                 {
                     offset = ZoneOffset.UTC;

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
 {
@@ -36,7 +36,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         private Map<String, Integer> m_methodMap;
         private boolean m_attached;
 
-        public PeripheralWrapper( IPeripheral peripheral, String side )
+        PeripheralWrapper( IPeripheral peripheral, String side )
         {
             super( m_environment );
             m_side = side;
@@ -282,9 +282,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "peripheral"
-        };
+        return new String[] { "peripheral" };
     }
 
     @Override
@@ -326,7 +324,7 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
             "isPresent",
             "getType",
             "getMethods",
-            "call"
+            "call",
         };
     }
 
@@ -356,7 +354,6 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
                 ComputerSide side = ComputerSide.valueOfInsensitive( getString( args, 0 ) );
                 if( side != null )
                 {
-                    String type = null;
                     synchronized( m_peripherals )
                     {
                         PeripheralWrapper p = m_peripherals[side.ordinal()];

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
 {
@@ -29,9 +29,7 @@ public class RedstoneAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "rs", "redstone"
-        };
+        return new String[] { "rs", "redstone" };
     }
 
     @Nonnull

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
 {
@@ -33,9 +33,7 @@ public class TermAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "term"
-        };
+        return new String[] { "term" };
     }
 
     @Nonnull
@@ -89,9 +87,7 @@ public class TermAPI implements ILuaAPI
 
     public static Object[] encodeColour( int colour ) throws LuaException
     {
-        return new Object[] {
-            1 << colour
-        };
+        return new Object[] { 1 << colour };
     }
 
     public static void setColour( Terminal terminal, int colour, double r, double g, double b )
@@ -246,9 +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
 {
@@ -212,6 +212,7 @@ public class BinaryReadableHandle extends HandleGeneric
                 }
             }
             case 3: // close
+                checkOpen();
                 close();
                 return null;
             case 4: // seek

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;
                 }
@@ -95,6 +95,7 @@ public class BinaryWritableHandle extends HandleGeneric
                     return null;
                 }
             case 2: // close
+                checkOpen();
                 close();
                 return null;
             case 3: // seek

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
 {
@@ -152,6 +152,7 @@ public class EncodedReadableHandle extends HandleGeneric
                     return null;
                 }
             case 3: // close
+                checkOpen();
                 close();
                 return null;
             default:

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

@@ -93,6 +93,7 @@ public class EncodedWritableHandle extends HandleGeneric
                     return null;
                 }
             case 3: // close
+                checkOpen();
                 close();
                 return null;
             default:

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
 {
@@ -37,12 +37,17 @@ public abstract class HandleGeneric implements ILuaObject
     protected final void close()
     {
         m_open = false;
-        IoUtil.closeQuietly( m_closable );
-        m_closable = null;
+
+        Closeable closeable = m_closable;
+        if( closeable != null )
+        {
+            IoUtil.closeQuietly( closeable );
+            m_closable = null;
+        }
     }
 
     /**
-     * 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()
     {
@@ -72,13 +75,15 @@ public abstract class Resource<T extends Resource<T>> implements Closeable
      */
     protected void dispose()
     {
-        @SuppressWarnings( "unchecked" ) T thisT = (T) this;
+        @SuppressWarnings( "unchecked" )
+        T thisT = (T) this;
         limiter.release( thisT );
     }
 
     /**
      * 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.
      */
@@ -95,7 +100,8 @@ public abstract class Resource<T extends Resource<T>> implements Closeable
 
     public boolean queue( Consumer<T> task )
     {
-        @SuppressWarnings( "unchecked" ) T thisT = (T) this;
+        @SuppressWarnings( "unchecked" )
+        T thisT = (T) this;
         return limiter.queue( thisT, () -> task.accept( thisT ) );
     }
 

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/Computer.java

@@ -239,7 +239,6 @@ public class Computer
     }
 
     @Deprecated
-    @SuppressWarnings( "unused" )
     public void advance( double dt )
     {
         tick();

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

@@ -268,7 +268,7 @@ 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

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

@@ -30,7 +30,10 @@ public enum ComputerSide
 
     private final String name;
 
-    ComputerSide( String name ) {this.name = name;}
+    ComputerSide( String name )
+    {
+        this.name = name;
+    }
 
     @Nonnull
     public static ComputerSide valueOf( int side )

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/ComboMount.java

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.filesystem;
 
+import dan200.computercraft.api.filesystem.FileOperationException;
 import dan200.computercraft.api.filesystem.IMount;
 
 import javax.annotation.Nonnull;
@@ -95,7 +96,7 @@ public class ComboMount implements IMount
         }
         else
         {
-            throw new IOException( "/" + path + ": Not a directory" );
+            throw new FileOperationException( path, "Not a directory" );
         }
     }
 
@@ -110,7 +111,7 @@ public class ComboMount implements IMount
                 return part.getSize( path );
             }
         }
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -126,7 +127,7 @@ public class ComboMount implements IMount
                 return part.openForRead( path );
             }
         }
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -141,6 +142,6 @@ public class ComboMount implements IMount
                 return part.openChannelForRead( path );
             }
         }
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 }

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

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.core.filesystem;
 
+import dan200.computercraft.api.filesystem.FileOperationException;
 import dan200.computercraft.api.filesystem.IMount;
 
 import javax.annotation.Nonnull;
@@ -44,7 +45,7 @@ public class EmptyMount implements IMount
     @Deprecated
     public InputStream openForRead( @Nonnull String path ) throws IOException
     {
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -52,6 +53,6 @@ public class EmptyMount implements IMount
     @Deprecated
     public ReadableByteChannel openChannelForRead( @Nonnull String path ) throws IOException
     {
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 }

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

@@ -7,6 +7,7 @@
 package dan200.computercraft.core.filesystem;
 
 import com.google.common.collect.Sets;
+import dan200.computercraft.api.filesystem.FileOperationException;
 import dan200.computercraft.api.filesystem.IWritableMount;
 
 import javax.annotation.Nonnull;
@@ -167,12 +168,12 @@ public class FileMount implements IWritableMount
     {
         if( !created() )
         {
-            if( !path.isEmpty() ) throw new IOException( "/" + path + ": Not a directory" );
+            if( !path.isEmpty() ) throw new FileOperationException( path, "Not a directory" );
             return;
         }
 
         File file = getRealPath( path );
-        if( !file.exists() || !file.isDirectory() ) throw new IOException( "/" + path + ": Not a directory" );
+        if( !file.exists() || !file.isDirectory() ) throw new FileOperationException( path, "Not a directory" );
 
         String[] paths = file.list();
         for( String subPath : paths )
@@ -194,7 +195,7 @@ public class FileMount implements IWritableMount
             if( file.exists() ) return file.isDirectory() ? 0 : file.length();
         }
 
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -208,7 +209,7 @@ public class FileMount implements IWritableMount
             if( file.exists() && !file.isDirectory() ) return new FileInputStream( file );
         }
 
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -221,7 +222,7 @@ public class FileMount implements IWritableMount
             if( file.exists() && !file.isDirectory() ) return FileChannel.open( file.toPath(), READ_OPTIONS );
         }
 
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     // IWritableMount implementation
@@ -233,7 +234,7 @@ public class FileMount implements IWritableMount
         File file = getRealPath( path );
         if( file.exists() )
         {
-            if( !file.isDirectory() ) throw new IOException( "/" + path + ": File exists" );
+            if( !file.isDirectory() ) throw new FileOperationException( path, "File exists" );
             return;
         }
 
@@ -247,7 +248,7 @@ public class FileMount implements IWritableMount
 
         if( getRemainingSpace() < dirsToCreate * MINIMUM_FILE_SIZE )
         {
-            throw new IOException( "/" + path + ": Out of space" );
+            throw new FileOperationException( path, "Out of space" );
         }
 
         if( file.mkdirs() )
@@ -256,14 +257,14 @@ public class FileMount implements IWritableMount
         }
         else
         {
-            throw new IOException( "/" + path + ": Access denied" );
+            throw new FileOperationException( path, "Access denied" );
         }
     }
 
     @Override
     public void delete( @Nonnull String path ) throws IOException
     {
-        if( path.isEmpty() ) throw new IOException( "/" + path + ": Access denied" );
+        if( path.isEmpty() ) throw new FileOperationException( path, "Access denied" );
 
         if( created() )
         {
@@ -319,7 +320,7 @@ public class FileMount implements IWritableMount
     {
         create();
         File file = getRealPath( path );
-        if( file.exists() && file.isDirectory() ) throw new IOException( "/" + path + ": Cannot write to directory" );
+        if( file.exists() && file.isDirectory() ) throw new FileOperationException( path, "Cannot write to directory" );
 
         if( file.exists() )
         {
@@ -327,7 +328,7 @@ public class FileMount implements IWritableMount
         }
         else if( getRemainingSpace() < MINIMUM_FILE_SIZE )
         {
-            throw new IOException( "/" + path + ": Out of space" );
+            throw new FileOperationException( path, "Out of space" );
         }
         m_usedSpace += MINIMUM_FILE_SIZE;
 
@@ -340,12 +341,12 @@ public class FileMount implements IWritableMount
     {
         if( !created() )
         {
-            throw new IOException( "/" + path + ": No such file" );
+            throw new FileOperationException( path, "No such file" );
         }
 
         File file = getRealPath( path );
-        if( !file.exists() ) throw new IOException( "/" + path + ": No such file" );
-        if( file.isDirectory() ) throw new IOException( "/" + path + ": Cannot write to directory" );
+        if( !file.exists() ) throw new FileOperationException( path, "No such file" );
+        if( file.isDirectory() ) throw new FileOperationException( path, "Cannot write to directory" );
 
         // Allowing seeking when appending is not recommended, so we use a separate channel.
         return new WritableCountingChannel(

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

@@ -8,6 +8,7 @@ package dan200.computercraft.core.filesystem;
 
 import com.google.common.io.ByteStreams;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.filesystem.FileOperationException;
 import dan200.computercraft.api.filesystem.IFileSystem;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.api.filesystem.IWritableMount;
@@ -45,7 +46,7 @@ public class FileSystem
             m_writableMount = null;
         }
 
-        public MountWrapper( String label, String location, IWritableMount mount )
+        MountWrapper( String label, String location, IWritableMount mount )
         {
             this( label, location, (IMount) mount );
             m_writableMount = mount;
@@ -107,7 +108,7 @@ public class FileSystem
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
@@ -122,12 +123,12 @@ public class FileSystem
                 }
                 else
                 {
-                    throw new FileSystemException( "/" + path + ": Not a directory" );
+                    throw localExceptionOf( path, "Not a directory" );
                 }
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
@@ -149,12 +150,12 @@ public class FileSystem
                 }
                 else
                 {
-                    throw new FileSystemException( "/" + path + ": No such file" );
+                    throw localExceptionOf( path, "No such file" );
                 }
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
@@ -169,12 +170,12 @@ public class FileSystem
                 }
                 else
                 {
-                    throw new FileSystemException( "/" + path + ": No such file" );
+                    throw localExceptionOf( path, "No such file" );
                 }
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
@@ -182,19 +183,14 @@ public class FileSystem
 
         public void makeDirectory( String path ) throws FileSystemException
         {
-            if( m_writableMount == null )
-            {
-                throw new FileSystemException( "/" + path + ": Access denied" );
-            }
+            if( m_writableMount == null ) throw exceptionOf( path, "Access denied" );
+
+            path = toLocal( path );
             try
             {
-                path = toLocal( path );
                 if( m_mount.exists( path ) )
                 {
-                    if( !m_mount.isDirectory( path ) )
-                    {
-                        throw new FileSystemException( "/" + path + ": File exists" );
-                    }
+                    if( !m_mount.isDirectory( path ) ) throw localExceptionOf( path, "File exists" );
                 }
                 else
                 {
@@ -203,16 +199,14 @@ public class FileSystem
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
         public void delete( String path ) throws FileSystemException
         {
-            if( m_writableMount == null )
-            {
-                throw new FileSystemException( "/" + path + ": Access denied" );
-            }
+            if( m_writableMount == null ) throw exceptionOf( path, "Access denied" );
+
             try
             {
                 path = toLocal( path );
@@ -227,22 +221,20 @@ public class FileSystem
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
         public WritableByteChannel openForWrite( String path ) throws FileSystemException
         {
-            if( m_writableMount == null )
-            {
-                throw new FileSystemException( "/" + path + ": Access denied" );
-            }
+            if( m_writableMount == null ) throw exceptionOf( path, "Access denied" );
+
+            path = toLocal( path );
             try
             {
-                path = toLocal( path );
                 if( m_mount.exists( path ) && m_mount.isDirectory( path ) )
                 {
-                    throw new FileSystemException( "/" + path + ": Cannot write to directory" );
+                    throw localExceptionOf( path, "Cannot write to directory" );
                 }
                 else
                 {
@@ -263,19 +255,17 @@ public class FileSystem
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
         public WritableByteChannel openForAppend( String path ) throws FileSystemException
         {
-            if( m_writableMount == null )
-            {
-                throw new FileSystemException( "/" + path + ": Access denied" );
-            }
+            if( m_writableMount == null ) throw exceptionOf( path, "Access denied" );
+
+            path = toLocal( path );
             try
             {
-                path = toLocal( path );
                 if( !m_mount.exists( path ) )
                 {
                     if( !path.isEmpty() )
@@ -290,7 +280,7 @@ public class FileSystem
                 }
                 else if( m_mount.isDirectory( path ) )
                 {
-                    throw new FileSystemException( "/" + path + ": Cannot write to directory" );
+                    throw localExceptionOf( path, "Cannot write to directory" );
                 }
                 else
                 {
@@ -303,16 +293,36 @@ public class FileSystem
             }
             catch( IOException e )
             {
-                throw new FileSystemException( e.getMessage() );
+                throw localExceptionOf( e );
             }
         }
 
-        // private members
-
         private String toLocal( String path )
         {
             return FileSystem.toLocal( path, m_location );
         }
+
+        private FileSystemException localExceptionOf( IOException e )
+        {
+            if( !m_location.isEmpty() && e instanceof FileOperationException )
+            {
+                FileOperationException ex = (FileOperationException) e;
+                if( ex.getFilename() != null ) return localExceptionOf( ex.getFilename(), ex.getMessage() );
+            }
+
+            return new FileSystemException( e.getMessage() );
+        }
+
+        private FileSystemException localExceptionOf( String path, String message )
+        {
+            if( !m_location.isEmpty() ) path = path.isEmpty() ? m_location : m_location + "/" + path;
+            return exceptionOf( path, message );
+        }
+
+        private static FileSystemException exceptionOf( String path, String message )
+        {
+            return new FileSystemException( "/" + path + ": " + message );
+        }
     }
 
     private final FileSystemWrapperMount m_wrapper = new FileSystemWrapperMount( this );
@@ -769,7 +779,7 @@ public class FileSystem
 
         // Clean the path or illegal characters.
         final char[] specialChars = new char[] {
-            '"', ':', '<', '>', '?', '|' // Sorted by ascii value (important)
+            '"', ':', '<', '>', '?', '|', // Sorted by ascii value (important)
         };
 
         StringBuilder cleanName = new StringBuilder();

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

@@ -9,6 +9,7 @@ package dan200.computercraft.core.filesystem;
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
 import com.google.common.io.ByteStreams;
+import dan200.computercraft.api.filesystem.FileOperationException;
 import dan200.computercraft.api.filesystem.IMount;
 import dan200.computercraft.core.apis.handles.ArrayByteChannel;
 import dan200.computercraft.shared.util.IoUtil;
@@ -92,7 +93,7 @@ public class JarMount implements IMount
         new MountReference( this );
 
         // Read in all the entries
-        root = new FileEntry( "" );
+        root = new FileEntry();
         Enumeration<? extends ZipEntry> zipEntries = zip.entries();
         while( zipEntries.hasMoreElements() )
         {
@@ -139,7 +140,7 @@ public class JarMount implements IMount
             FileEntry nextEntry = lastEntry.children.get( part );
             if( nextEntry == null || !nextEntry.isDirectory() )
             {
-                lastEntry.children.put( part, nextEntry = new FileEntry( part ) );
+                lastEntry.children.put( part, nextEntry = new FileEntry() );
             }
 
             lastEntry = nextEntry;
@@ -166,7 +167,7 @@ public class JarMount implements IMount
     public void list( @Nonnull String path, @Nonnull List<String> contents ) throws IOException
     {
         FileEntry file = get( path );
-        if( file == null || !file.isDirectory() ) throw new IOException( "/" + path + ": Not a directory" );
+        if( file == null || !file.isDirectory() ) throw new FileOperationException( path, "Not a directory" );
 
         file.list( contents );
     }
@@ -176,7 +177,7 @@ public class JarMount implements IMount
     {
         FileEntry file = get( path );
         if( file != null ) return file.size;
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     @Nonnull
@@ -218,22 +219,15 @@ public class JarMount implements IMount
             }
         }
 
-        throw new IOException( "/" + path + ": No such file" );
+        throw new FileOperationException( path, "No such file" );
     }
 
     private static class FileEntry
     {
-        final String name;
-
         String path;
         long size;
         Map<String, FileEntry> children;
 
-        FileEntry( String name )
-        {
-            this.name = name;
-        }
-
         void setup( ZipEntry entry )
         {
             path = entry.getName();

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

@@ -550,7 +550,7 @@ public class CobaltLuaMachine implements ILuaMachine
                 {
                     if( ComputerCraft.logPeripheralErrors ) ComputerCraft.log.error( "Error running task", t );
                     m_computer.queueEvent( "task_complete", new Object[] {
-                        taskID, false, "Java Exception Thrown: " + t
+                        taskID, false, "Java Exception Thrown: " + t,
                     } );
                 }
             };

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/core/terminal/TextBuffer.java

@@ -8,7 +8,7 @@ package dan200.computercraft.core.terminal;
 
 public class TextBuffer
 {
-    public char[] m_text;
+    private final char[] m_text;
 
     public TextBuffer( char c, int length )
     {

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

@@ -277,7 +277,7 @@ public final class Config
             renameProperty( CATEGORY_GENERAL, "turtlesCanPush", CATEGORY_TURTLE, "can_push" );
             renameProperty( CATEGORY_GENERAL, "turtle_disabled_actions", CATEGORY_TURTLE, "disabled_actions" );
 
-            config.getCategory( CATEGORY_HTTP )
+            config.getCategory( CATEGORY_TURTLE )
                 .setComment( "Various options relating to turtles." );
 
             turtlesNeedFuel = config.get( CATEGORY_TURTLE, "need_fuel", ComputerCraft.turtlesNeedFuel );

src/main/java/dan200/computercraft/shared/command/framework/CommandRoot.java

@@ -18,7 +18,7 @@ import java.util.List;
 import java.util.Map;
 
 /**
- * A command which delegates to a series of sub commands
+ * A command which delegates to a series of sub commands.
  */
 public class CommandRoot implements ISubCommand
 {

src/main/java/dan200/computercraft/shared/command/framework/ISubCommand.java

@@ -22,7 +22,7 @@ import java.util.List;
 public interface ISubCommand
 {
     /**
-     * Get the name of this command
+     * Get the name of this command.
      *
      * @return The name of this command
      * @see ICommand#getName()
@@ -40,7 +40,7 @@ public interface ISubCommand
     String getFullName();
 
     /**
-     * Get the usage of this command
+     * Get the usage of this command.
      *
      * @param context The context this command is executed in
      * @return The usage of this command
@@ -62,16 +62,17 @@ public interface ISubCommand
     boolean checkPermission( @Nonnull CommandContext context );
 
     /**
-     * Execute this command
+     * Execute this command.
      *
      * @param context   The current command context.
-     * @param arguments The arguments passed  @throws CommandException When an error occurs
+     * @param arguments The arguments passed
+     * @throws CommandException When an error occurs
      * @see ICommand#execute(MinecraftServer, ICommandSender, String[])
      */
     void execute( @Nonnull CommandContext context, @Nonnull List<String> arguments ) throws CommandException;
 
     /**
-     * Get a list of possible completions
+     * Get a list of possible completions.
      *
      * @param context   The current command context.
      * @param arguments The arguments passed. You should complete the last one.

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

@@ -15,7 +15,7 @@ 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/BlockGeneric.java

@@ -51,7 +51,6 @@ public abstract class BlockGeneric extends Block implements ITileEntityProvider
 
     @Override
     @Deprecated
-    @SuppressWarnings( "deprecation" )
     public final void neighborChanged( IBlockState state, World world, BlockPos pos, Block neighbourBlock, BlockPos neighbourPos )
     {
         TileEntity tile = world.getTileEntity( pos );

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

@@ -63,7 +63,6 @@ public abstract class TileGeneric extends TileEntity
     {
     }
 
-    @SuppressWarnings( "deprecation" )
     public void onNeighbourChange( @Nonnull BlockPos neighbour )
     {
         onNeighbourChange();

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

@@ -30,8 +30,8 @@ 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
 {
@@ -47,9 +47,7 @@ public class CommandAPI implements ILuaAPI
     @Override
     public String[] getNames()
     {
-        return new String[] {
-            "commands"
-        };
+        return new String[] { "commands" };
     }
 
     @Nonnull
@@ -62,7 +60,7 @@ public class CommandAPI implements ILuaAPI
             "list",
             "getBlockPosition",
             "getBlockInfos",
-            "getBlockInfo"
+            "getBlockInfo",
         };
     }
 
@@ -85,7 +83,7 @@ public class CommandAPI implements ILuaAPI
         {
             sender.clearOutput();
             int result = commandManager.executeCommand( sender, command );
-            return new Object[] { result > 0, sender.copyOutput() };
+            return new Object[] { result > 0, sender.copyOutput(), result };
         }
         catch( Throwable t )
         {
@@ -206,7 +204,7 @@ 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 )
                     {
@@ -245,7 +243,7 @@ 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/TileComputer.java

@@ -32,7 +32,7 @@ public class TileComputer extends TileComputerBase
         ServerComputer computer = new ServerComputer(
             getWorld(),
             id,
-            m_label,
+            label,
             instanceID,
             family,
             ComputerCraft.terminalWidth_computer,

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

@@ -47,7 +47,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
 {
     private int m_instanceID = -1;
     private int m_computerID = -1;
-    protected String m_label = null;
+    protected String label = null;
     private boolean m_on = false;
     boolean m_startOn = false;
     private boolean m_fresh = false;
@@ -190,7 +190,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
 
                 m_fresh = false;
                 m_computerID = computer.getID();
-                m_label = computer.getLabel();
+                label = computer.getLabel();
                 m_on = computer.isOn();
 
                 if( computer.hasOutputChanged() ) updateOutput();
@@ -212,9 +212,9 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
         {
             nbt.setInteger( "computerID", m_computerID );
         }
-        if( m_label != null )
+        if( label != null )
         {
-            nbt.setString( "label", m_label );
+            nbt.setString( "label", label );
         }
         nbt.setBoolean( "on", m_on );
         return super.writeToNBT( nbt );
@@ -248,7 +248,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
         m_computerID = id;
 
         // Load label
-        m_label = nbt.hasKey( "label" ) ? nbt.getString( "label" ) : null;
+        label = nbt.hasKey( "label" ) ? nbt.getString( "label" ) : null;
 
         // Load power state
         m_startOn = nbt.getBoolean( "on" );
@@ -280,7 +280,7 @@ 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
@@ -361,7 +361,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     @Override
     public final String getLabel()
     {
-        return m_label;
+        return label;
     }
 
     @Override
@@ -378,9 +378,9 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     @Override
     public final void setLabel( String label )
     {
-        if( getWorld().isRemote || Objects.equals( m_label, label ) ) return;
+        if( getWorld().isRemote || Objects.equals( this.label, label ) ) return;
 
-        m_label = label;
+        this.label = label;
         ServerComputer computer = getServerComputer();
         if( computer != null ) computer.setLabel( label );
         markDirty();
@@ -453,8 +453,8 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     protected void writeDescription( @Nonnull NBTTagCompound nbt )
     {
         super.writeDescription( nbt );
-        nbt.setInteger( "instanceID", createServerComputer().getInstanceID() );
-        if( m_label != null ) nbt.setString( "label", m_label );
+        if( m_instanceID >= 0 ) nbt.setInteger( "instanceID", m_instanceID );
+        if( label != null ) nbt.setString( "label", label );
         if( m_computerID >= 0 ) nbt.setInteger( "computerID", m_computerID );
     }
 
@@ -463,7 +463,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     {
         super.readDescription( nbt );
         m_instanceID = nbt.getInteger( "instanceID" );
-        m_label = nbt.hasKey( "label" ) ? nbt.getString( "label" ) : null;
+        label = nbt.hasKey( "label" ) ? nbt.getString( "label" ) : null;
         m_computerID = nbt.hasKey( "computerID" ) ? nbt.getInteger( "computerID" ) : -1;
     }
 
@@ -474,7 +474,7 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
             unload();
             m_instanceID = copy.m_instanceID;
             m_computerID = copy.m_computerID;
-            m_label = copy.m_label;
+            label = copy.label;
             m_on = copy.m_on;
             m_startOn = copy.m_startOn;
             updateBlock();
@@ -493,13 +493,13 @@ public abstract class TileComputerBase extends TileGeneric implements IComputerT
     @Override
     public String getName()
     {
-        return hasCustomName() ? m_label : getBlockType().getTranslationKey();
+        return hasCustomName() ? label : getBlockType().getTranslationKey();
     }
 
     @Override
     public boolean hasCustomName()
     {
-        return !Strings.isNullOrEmpty( m_label );
+        return !Strings.isNullOrEmpty( label );
     }
 
     @Nonnull

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

@@ -11,9 +11,9 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Random;
 
-public class ComputerRegistry<TComputer extends IComputer>
+public class ComputerRegistry<T extends IComputer>
 {
-    private Map<Integer, TComputer> m_computers;
+    private Map<Integer, T> m_computers;
     private int m_nextUnusedInstanceID;
     private int m_sessionID;
 
@@ -33,12 +33,12 @@ public class ComputerRegistry<TComputer extends IComputer>
         return m_nextUnusedInstanceID++;
     }
 
-    public Collection<TComputer> getComputers()
+    public Collection<T> getComputers()
     {
         return m_computers.values();
     }
 
-    public TComputer get( int instanceID )
+    public T get( int instanceID )
     {
         if( instanceID >= 0 )
         {
@@ -55,7 +55,7 @@ public class ComputerRegistry<TComputer extends IComputer>
         return m_computers.containsKey( instanceID );
     }
 
-    public void add( int instanceID, TComputer computer )
+    public void add( int instanceID, T computer )
     {
         if( m_computers.containsKey( instanceID ) )
         {

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

@@ -220,6 +220,13 @@ public class ServerComputer extends ServerTerminal implements IComputer, IComput
         return m_instanceID;
     }
 
+    /*
+     * getID and getLabel are deprecated on IComputer, as they do not make sense in ClientComputer.
+     * However, for compatibility reasons, we still need these here, and have no choice but to override the IComputer methods.
+     *
+     * Hence, we suppress the deprecation warning.
+     */
+
     @Override
     @SuppressWarnings( "deprecation" )
     public int getID()

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

@@ -1,9 +1,8 @@
 /*
  * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2018. Do not distribute without permission.
+ * 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;

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

@@ -1,9 +1,8 @@
 /*
  * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2018. Do not distribute without permission.
+ * 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;

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

@@ -1,9 +1,8 @@
 /*
  * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2018. Do not distribute without permission.
+ * 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;

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

@@ -90,6 +90,7 @@ public class JEIComputerCraft implements IModPlugin
         ingredients.addIngredientsAtRuntime( VanillaTypes.ITEM, upgradeItems );
 
         // Hide all upgrade recipes
+        @SuppressWarnings( "unchecked" )
         IRecipeCategory<? extends IRecipeWrapper> category = (IRecipeCategory<? extends IRecipeWrapper>) registry.getRecipeCategory( VanillaRecipeCategoryUid.CRAFTING );
         if( category != null )
         {
@@ -107,7 +108,7 @@ 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();
@@ -131,7 +132,7 @@ 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();
@@ -151,7 +152,7 @@ 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/media/inventory/ContainerHeldItem.java

@@ -6,7 +6,6 @@
 
 package dan200.computercraft.shared.media.inventory;
 
-import dan200.computercraft.shared.util.InventoryUtil;
 import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.inventory.Container;
 import net.minecraft.item.ItemStack;
@@ -22,7 +21,7 @@ public class ContainerHeldItem extends Container
     public ContainerHeldItem( EntityPlayer player, EnumHand hand )
     {
         m_hand = hand;
-        m_stack = InventoryUtil.copyItem( player.getHeldItem( hand ) );
+        m_stack = player.getHeldItem( hand ).copy();
     }
 
     @Nonnull

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

@@ -15,7 +15,7 @@ import net.minecraft.util.SoundEvent;
 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

@@ -72,6 +72,7 @@ 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 side    The side to register this packet handler under
      * @param factory The factory for this type of packet.

src/main/java/dan200/computercraft/shared/peripheral/PeripheralType.java

@@ -39,5 +39,8 @@ public enum PeripheralType implements IStringSerializable
     }
 
     @Override
-    public String toString() { return name; }
+    public String toString()
+    {
+        return name;
+    }
 }

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

@@ -14,7 +14,7 @@ import net.minecraft.tileentity.TileEntityCommandBlock;
 
 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
 {
@@ -52,7 +52,7 @@ public class CommandBlockPeripheral implements IPeripheral
         {
             case 0: // getCommand
                 return context.executeMainThreadTask( () -> new Object[] {
-                    m_commandBlock.getCommandBlockLogic().getCommand()
+                    m_commandBlock.getCommandBlockLogic().getCommand(),
                 } );
             case 1:
             {