I do declare

- Move source set bundling/common source set sharing logic into
  transitiveSourceSets and make it more flexible
- Remove commonProject field from platform extension

buildSrc/src/main/kotlin/dev/engine_room/gradle/platform/PlatformExtension.kt

@@ -1,25 +1,18 @@
 package dev.engine_room.gradle.platform
 
-import dev.engine_room.gradle.jarset.JarTaskSet
 import net.fabricmc.loom.api.LoomGradleExtensionAPI
 import net.fabricmc.loom.task.RemapJarTask
 import org.gradle.api.Project
 import org.gradle.api.Task
 import org.gradle.api.tasks.SourceSet
-import org.gradle.api.tasks.SourceSetContainer
-import org.gradle.api.tasks.compile.JavaCompile
-import org.gradle.api.tasks.javadoc.Javadoc
 import org.gradle.jvm.tasks.Jar
-import org.gradle.kotlin.dsl.*
-import org.gradle.language.jvm.tasks.ProcessResources
+import org.gradle.kotlin.dsl.assign
+import org.gradle.kotlin.dsl.named
+import org.gradle.kotlin.dsl.register
+import org.gradle.kotlin.dsl.the
 import java.io.File
-import kotlin.properties.Delegates
 
 open class PlatformExtension(val project: Project) {
-    var commonProject: Project by Delegates.notNull()
-
-    val commonSourceSets: SourceSetContainer by lazy { commonProject.the<SourceSetContainer>() }
-
     fun setupLoomMod(vararg sourceSets: SourceSet) {
         project.the<LoomGradleExtensionAPI>().mods.maybeCreate("main").apply {
             sourceSets.forEach(::sourceSet)
@@ -51,52 +44,6 @@ open class PlatformExtension(val project: Project) {
         }
     }
 
-    fun compileWithCommonSourceSets(vararg sourceSets: SourceSet) {
-        project.tasks.apply {
-            withType<JavaCompile>().configureEach {
-                JarTaskSet.excludeDuplicatePackageInfos(this)
-            }
-
-            sourceSets.forEach {
-                val commonSourceSet = commonSourceSets.named(it.name).get()
-
-                named<JavaCompile>(it.compileJavaTaskName).configure {
-                    source(commonSourceSet.allJava)
-                }
-                named<ProcessResources>(it.processResourcesTaskName).configure {
-                    from(commonSourceSet.resources)
-                }
-            }
-        }
-    }
-
-    fun setupFatJar(vararg sourceSets: SourceSet) {
-        project.tasks.apply {
-            val extraSourceSets = sourceSets.filter { it.name != "main" }.toList()
-            val commonSources = sourceSets.map { commonSourceSets.named(it.name).get() }
-
-            named<Jar>("jar").configure {
-                extraSourceSets.forEach { from(it.output) }
-
-                JarTaskSet.excludeDuplicatePackageInfos(this)
-            }
-
-            named<Javadoc>("javadoc").configure {
-                commonSources.forEach { source(it.allJava) }
-                extraSourceSets.forEach { source(it.allJava) }
-
-                JarTaskSet.excludeDuplicatePackageInfos(this)
-            }
-
-            named<Jar>("sourcesJar").configure {
-                commonSources.forEach { from(it.allJava) }
-                extraSourceSets.forEach { from(it.allJava) }
-
-                JarTaskSet.excludeDuplicatePackageInfos(this)
-            }
-        }
-    }
-
     fun setupTestMod(sourceSet: SourceSet) {
         project.tasks.apply {
             val testModJar = register<Jar>("testModJar") {

buildSrc/src/main/kotlin/dev/engine_room/gradle/transitive/TransitiveSourceSetConfigurator.kt

@@ -1,8 +1,14 @@
 package dev.engine_room.gradle.transitive
 
+import dev.engine_room.gradle.jarset.JarTaskSet
+import org.gradle.api.Project
 import org.gradle.api.tasks.SourceSet
+import org.gradle.api.tasks.SourceSetContainer
 import org.gradle.api.tasks.compile.JavaCompile
+import org.gradle.api.tasks.javadoc.Javadoc
+import org.gradle.jvm.tasks.Jar
 import org.gradle.kotlin.dsl.named
+import org.gradle.kotlin.dsl.the
 import org.gradle.language.jvm.tasks.ProcessResources
 
 class TransitiveSourceSetConfigurator(private val parent: TransitiveSourceSetsExtension, private val sourceSet: SourceSet) {
@@ -22,14 +28,21 @@ class TransitiveSourceSetConfigurator(private val parent: TransitiveSourceSetsEx
         rootRuntime()
     }
 
-    fun compile(vararg sourceSets: SourceSet) {
+    fun compileClasspath(vararg sourceSets: SourceSet) {
         compileSourceSets += sourceSets
         for (sourceSet in sourceSets) {
             this.sourceSet.compileClasspath += sourceSet.output
         }
     }
 
-    fun runtime(vararg sourceSets: SourceSet) {
+    fun compileClasspath(project: Project, vararg sourceSets: String) {
+        val externalSourceSets = project.the<SourceSetContainer>()
+        for (name in sourceSets) {
+            this.sourceSet.compileClasspath += externalSourceSets.getByName(name).output
+        }
+    }
+
+    fun runtimeClasspath(vararg sourceSets: SourceSet) {
         runtimeSourceSets += sourceSets
         for (sourceSet in sourceSets) {
             this.sourceSet.runtimeClasspath += sourceSet.output
@@ -37,8 +50,77 @@ class TransitiveSourceSetConfigurator(private val parent: TransitiveSourceSetsEx
     }
 
     fun implementation(vararg sourceSets: SourceSet) {
-        compile(*sourceSets)
-        runtime(*sourceSets)
+        compileClasspath(*sourceSets)
+        runtimeClasspath(*sourceSets)
+    }
+
+    fun from(otherProject: Project) {
+        from(otherProject, sourceSet.name)
+    }
+
+    fun from(otherProject: Project, vararg names: String) {
+
+        val otherSourceSets = otherProject.the<SourceSetContainer>()
+
+        from(*names.map { otherSourceSets.getByName(it) }.toTypedArray())
+    }
+
+    fun from(vararg sourceSets: SourceSet) {
+        parent.project.tasks.apply {
+            named<JavaCompile>(sourceSet.compileJavaTaskName).configure {
+                sourceSets.forEach { source(it.allJava) }
+
+                JarTaskSet.excludeDuplicatePackageInfos(this)
+            }
+            named<ProcessResources>(sourceSet.processResourcesTaskName).configure {
+                sourceSets.forEach { from(it.resources) }
+            }
+        }
+    }
+
+    fun bundleFrom(otherProject: Project) {
+        bundleFrom(otherProject, sourceSet.name)
+    }
+
+    fun bundleFrom(otherProject: Project, vararg names: String) {
+        val otherSourceSets = otherProject.the<SourceSetContainer>()
+
+        bundleFrom(*names.map { otherSourceSets.getByName(it) }.toTypedArray())
+    }
+
+    fun bundleFrom(vararg sourceSets: SourceSet) {
+        from(*sourceSets)
+        // The external sourceSets will be included in the jar by default since we bring it into the java compile task,
+        // however we need to make sure that the javadoc and sources jars also include the external sourceSets
+        bundleJavadocAndSources(*sourceSets)
+    }
+
+    fun bundleOutput(vararg sourceSets: SourceSet) {
+        bundleJavadocAndSources(*sourceSets)
+
+        parent.project.tasks.apply {
+            named<Jar>(sourceSet.jarTaskName).configure {
+                sourceSets.forEach { from(it.output) }
+
+                JarTaskSet.excludeDuplicatePackageInfos(this)
+            }
+        }
+    }
+
+    private fun bundleJavadocAndSources(vararg sourceSets: SourceSet) {
+        parent.project.tasks.apply {
+            named<Javadoc>(sourceSet.javadocTaskName).configure {
+                sourceSets.forEach { source(it.allJava) }
+
+                JarTaskSet.excludeDuplicatePackageInfos(this)
+            }
+
+            named<Jar>(sourceSet.sourcesJarTaskName).configure {
+                sourceSets.forEach { from(it.allJava) }
+
+                JarTaskSet.excludeDuplicatePackageInfos(this)
+            }
+        }
     }
 
     fun outgoing() {

common/build.gradle.kts

@@ -24,12 +24,12 @@ transitiveSourceSets {
     }
     sourceSet(lib) {
         rootCompile()
-        compile(api)
+        compileClasspath(api)
         outgoing()
     }
     sourceSet(backend) {
         rootCompile()
-        compile(api, lib)
+        compileClasspath(api, lib)
         outgoing()
     }
     sourceSet(stubs) {
@@ -37,7 +37,7 @@ transitiveSourceSets {
         outgoingClasses()
     }
     sourceSet(main) {
-        compile(api, lib, backend, stubs)
+        compileClasspath(api, lib, backend, stubs)
         outgoing()
     }
     sourceSet(sourceSets.getByName("test")) {
@@ -45,7 +45,7 @@ transitiveSourceSets {
     }
     sourceSet(vanillin) {
         rootCompile()
-        compile(api, lib)
+        compileClasspath(api, lib)
         outgoing()
     }
 }

fabric/build.gradle.kts

@@ -7,6 +7,9 @@ plugins {
     id("flywheel.platform")
 }
 
+val common = ":common"
+val commonProject = project(common)
+
 subproject.init("flywheel-fabric", "flywheel_group", "flywheel_version")
 
 val api = sourceSets.create("api")
@@ -21,22 +24,34 @@ transitiveSourceSets {
 
     sourceSet(api) {
         rootCompile()
+
+        from(commonProject)
     }
     sourceSet(lib) {
         rootCompile()
-        compile(api)
+        compileClasspath(api)
+
+        from(commonProject)
     }
     sourceSet(backend) {
         rootCompile()
-        compile(api, lib)
+        compileClasspath(api, lib)
+
+        from(commonProject)
     }
     sourceSet(stubs) {
         rootCompile()
+
+        from(commonProject)
     }
     sourceSet(main) {
         // Don't want stubs at runtime
-        compile(stubs)
+        compileClasspath(stubs)
         implementation(api, lib, backend)
+
+        bundleFrom(commonProject)
+
+        bundleOutput(api, lib, backend)
     }
     sourceSet(testMod) {
         rootCompile()
@@ -46,11 +61,8 @@ transitiveSourceSets {
 }
 
 platform {
-    commonProject = project(":common")
-    compileWithCommonSourceSets(api, lib, backend, stubs, main)
     setupLoomMod(api, lib, backend, main)
     setupLoomRuns()
-    setupFatJar(api, lib, backend, main)
     setupTestMod(testMod)
 }
 
@@ -88,13 +100,13 @@ dependencies {
 
     modCompileOnly("maven.modrinth:sodium:${property("sodium_version")}")
 
-    "forApi"(project(path = ":common", configuration = "apiClasses"))
-    "forLib"(project(path = ":common", configuration = "libClasses"))
-    "forBackend"(project(path = ":common", configuration = "backendClasses"))
-    "forStubs"(project(path = ":common", configuration = "stubsClasses"))
-    "forMain"(project(path = ":common", configuration = "mainClasses"))
+    "forApi"(project(path = common, configuration = "apiClasses"))
+    "forLib"(project(path = common, configuration = "libClasses"))
+    "forBackend"(project(path = common, configuration = "backendClasses"))
+    "forStubs"(project(path = common, configuration = "stubsClasses"))
+    "forMain"(project(path = common, configuration = "mainClasses"))
 
-    "forLib"(project(path = ":common", configuration = "libResources"))
-    "forBackend"(project(path = ":common", configuration = "backendResources"))
-    "forMain"(project(path = ":common", configuration = "mainResources"))
+    "forLib"(project(path = common, configuration = "libResources"))
+    "forBackend"(project(path = common, configuration = "backendResources"))
+    "forMain"(project(path = common, configuration = "mainResources"))
 }

forge/build.gradle.kts

@@ -7,6 +7,9 @@ plugins {
     id("flywheel.platform")
 }
 
+val common = ":common"
+val commonProject = project(common)
+
 subproject.init("flywheel-forge", "flywheel_group", "flywheel_version")
 
 val api = sourceSets.create("api")
@@ -21,20 +24,32 @@ transitiveSourceSets {
 
     sourceSet(api) {
         rootCompile()
+
+        from(commonProject)
     }
     sourceSet(lib) {
         rootCompile()
-        compile(api)
+        compileClasspath(api)
+
+        from(commonProject)
     }
     sourceSet(backend) {
         rootCompile()
-        compile(api, lib)
+        compileClasspath(api, lib)
+
+        from(commonProject)
     }
     sourceSet(stubs) {
         rootCompile()
+
+        from(commonProject)
     }
     sourceSet(main) {
-        compile(api, lib, backend, stubs)
+        compileClasspath(api, lib, backend, stubs)
+
+        bundleFrom(commonProject)
+
+        bundleOutput(api, lib, backend)
     }
     sourceSet(testMod) {
         rootCompile()
@@ -44,11 +59,8 @@ transitiveSourceSets {
 }
 
 platform {
-    commonProject = project(":common")
-    compileWithCommonSourceSets(api, lib, backend, stubs, main)
     setupLoomMod(api, lib, backend, main)
     setupLoomRuns()
-    setupFatJar(api, lib, backend, main)
     setupTestMod(testMod)
 }
 
@@ -97,13 +109,13 @@ dependencies {
 
     modCompileOnly("maven.modrinth:embeddium:${property("embeddium_version")}")
 
-    "forApi"(project(path = ":common", configuration = "apiClasses"))
-    "forLib"(project(path = ":common", configuration = "libClasses"))
-    "forBackend"(project(path = ":common", configuration = "backendClasses"))
-    "forStubs"(project(path = ":common", configuration = "stubsClasses"))
-    "forMain"(project(path = ":common", configuration = "mainClasses"))
+    "forApi"(project(path = common, configuration = "apiClasses"))
+    "forLib"(project(path = common, configuration = "libClasses"))
+    "forBackend"(project(path = common, configuration = "backendClasses"))
+    "forStubs"(project(path = common, configuration = "stubsClasses"))
+    "forMain"(project(path = common, configuration = "mainClasses"))
 
-    "forLib"(project(path = ":common", configuration = "libResources"))
-    "forBackend"(project(path = ":common", configuration = "backendResources"))
-    "forMain"(project(path = ":common", configuration = "mainResources"))
+    "forLib"(project(path = common, configuration = "libResources"))
+    "forBackend"(project(path = common, configuration = "backendResources"))
+    "forMain"(project(path = common, configuration = "mainResources"))
 }

vanillinFabric/build.gradle.kts

@@ -1,6 +1,3 @@
-import dev.engine_room.gradle.jarset.JarTaskSet
-import org.gradle.jvm.tasks.Jar
-
 plugins {
     idea
     java
@@ -10,41 +7,23 @@ plugins {
     id("flywheel.platform")
 }
 
+val common = ":common"
+val platform = ":fabric"
+
 subproject.init("vanillin-fabric", "vanillin_group", "vanillin_version")
 
 val main = sourceSets.getByName("main")
 
 platform {
-    commonProject = project(":common")
     setupLoomRuns()
 }
 
-listOf("api", "lib")
-    .map { project(":fabric").sourceSets.named(it).get() }
-    .forEach { main.compileClasspath += it.output }
+transitiveSourceSets {
+    sourceSet(main) {
+        compileClasspath(project(platform), "api", "lib")
 
-val commonSourceSet = platform.commonSourceSets.named("vanillin").get()
-
-tasks.named<Javadoc>("javadoc").configure {
-    source(commonSourceSet.allJava)
-
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-
-tasks.named<Jar>("sourcesJar").configure {
-    from(commonSourceSet.allJava)
-
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-
-tasks.withType<JavaCompile>().configureEach {
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-tasks.named<JavaCompile>(main.compileJavaTaskName).configure {
-    source(commonSourceSet.allJava)
-}
-tasks.named<ProcessResources>(main.processResourcesTaskName).configure {
-    from(commonSourceSet.resources)
+        bundleFrom(project(common), "vanillin")
+    }
 }
 
 jarSets {
@@ -68,10 +47,10 @@ dependencies {
 
     modCompileOnly("maven.modrinth:sodium:${property("sodium_version")}")
 
-    compileOnly(project(path = ":common", configuration = "vanillinClasses"))
-    compileOnly(project(path = ":common", configuration = "vanillinResources"))
+    compileOnly(project(path = common, configuration = "vanillinClasses"))
+    compileOnly(project(path = common, configuration = "vanillinResources"))
 
     // JiJ flywheel proper
-    include(project(path = ":fabric", configuration = "flywheelRemap"))
-    runtimeOnly(project(path = ":fabric", configuration = "flywheelDev"))
+    include(project(path = platform, configuration = "flywheelRemap"))
+    runtimeOnly(project(path = platform, configuration = "flywheelDev"))
 }

vanillinForge/build.gradle.kts

@@ -1,6 +1,3 @@
-import dev.engine_room.gradle.jarset.JarTaskSet
-import org.gradle.jvm.tasks.Jar
-
 plugins {
     idea
     java
@@ -10,41 +7,23 @@ plugins {
     id("flywheel.platform")
 }
 
+val common = ":common"
+val platform = ":forge"
+
 subproject.init("vanillin-forge", "vanillin_group", "vanillin_version")
 
 val main = sourceSets.getByName("main")
 
 platform {
-    commonProject = project(":common")
     setupLoomRuns()
 }
 
-listOf("api", "lib")
-    .map { project(":forge").sourceSets.named(it).get() }
-    .forEach { main.compileClasspath += it.output }
+transitiveSourceSets {
+    sourceSet(main) {
+        compileClasspath(project(platform), "api", "lib")
 
-val commonSourceSet = platform.commonSourceSets.named("vanillin").get()
-
-tasks.named<Javadoc>("javadoc").configure {
-    source(commonSourceSet.allJava)
-
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-
-tasks.named<Jar>("sourcesJar").configure {
-    from(commonSourceSet.allJava)
-
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-
-tasks.withType<JavaCompile>().configureEach {
-    JarTaskSet.excludeDuplicatePackageInfos(this)
-}
-tasks.named<JavaCompile>(main.compileJavaTaskName).configure {
-    source(commonSourceSet.allJava)
-}
-tasks.named<ProcessResources>(main.processResourcesTaskName).configure {
-    from(commonSourceSet.resources)
+        bundleFrom(project(common), "vanillin")
+    }
 }
 
 jarSets {
@@ -79,10 +58,10 @@ dependencies {
 
     modCompileOnly("maven.modrinth:embeddium:${property("embeddium_version")}")
 
-    compileOnly(project(path = ":common", configuration = "vanillinClasses"))
-    compileOnly(project(path = ":common", configuration = "vanillinResources"))
+    compileOnly(project(path = common, configuration = "vanillinClasses"))
+    compileOnly(project(path = common, configuration = "vanillinResources"))
 
     // JiJ flywheel proper
-    include(project(path = ":forge", configuration = "flywheelRemap"))
-    runtimeOnly(project(path = ":forge", configuration = "flywheelDev"))
+    include(project(path = platform, configuration = "flywheelRemap"))
+    runtimeOnly(project(path = platform, configuration = "flywheelDev"))
 }