Upstream KSP implementation

.github/workflows/build.yml

@@ -4,13 +4,15 @@ on: [push, pull_request]
 
 jobs:
   build:
+    name: 'Java ${{ matrix.java-version }} | KSP ${{ matrix.use-ksp }}'
     runs-on: ubuntu-latest
 
     strategy:
       fail-fast: false
       matrix:
         java-version:
           - 16
+        use-ksp: [ true, false ]
 
     steps:
       - name: Checkout
@@ -36,7 +38,7 @@ jobs:
           java-version: ${{ matrix.java-version }}
 
       - name: Test
-        run: ./gradlew build check --stacktrace
+        run: ./gradlew build check --stacktrace -PuseKsp=${{ matrix.use-ksp }}
 
       - name: Publish (default branch only)
         if: github.repository == 'square/moshi' && github.ref == 'refs/heads/master' && matrix.java-version == '16'

gradle.properties

@@ -16,34 +16,32 @@
 
 # For Dokka https://github.com/Kotlin/dokka/issues/1405
 org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8 \
-  --add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED \
-  --add-opens=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.jvm=ALL-UNNAMED  \
+  --add-opens=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED \
-  --add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
+  --add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
 
-# TODO move this to DSL in Kotlin 1.5.30 https://youtrack.jetbrains.com/issue/KT-44266
 kotlin.daemon.jvmargs=-Dfile.encoding=UTF-8 \
-  --add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED \
-  --add-opens=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.jvm=ALL-UNNAMED  \
+  --add-opens=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED \
+  --add-opens=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED \
-  --add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED \
   --add-opens=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED \
-  --add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
+  --add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
 
+# Kapt doesn't read the above jvm args when workers are used
+# https://youtrack.jetbrains.com/issue/KT-48402
+kapt.use.worker.api=false
 kapt.include.compile.classpath=false
 
 GROUP=com.squareup.moshi

gradle/libs.versions.toml

@@ -15,16 +15,17 @@
 [versions]
 autoService = "1.0"
 gjf = "1.11.0"
-incap = "0.3"
 jvmTarget = "1.8"
-kotlin = "1.5.21"
-kotlinCompileTesting = "1.4.3"
-kotlinpoet = "1.10.0"
+kotlin = "1.5.31"
+kotlinCompileTesting = "1.4.4"
+kotlinpoet = "1.10.1"
+ksp = "1.5.31-1.0.0"
 ktlint = "0.41.0"
 
 [plugins]
-dokka = { id = "org.jetbrains.dokka", version = "1.5.0" }
+dokka = { id = "org.jetbrains.dokka", version = "1.5.30" }
 japicmp = { id = "me.champeau.gradle.japicmp", version = "0.2.9" }
+ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
 mavenPublish = { id = "com.vanniktech.maven.publish", version = "0.17.0" }
 mavenShadow = { id = "com.github.johnrengelman.shadow", version = "7.0.0" }
 spotless = { id = "com.diffplug.spotless", version = "5.14.2" }
@@ -33,20 +34,22 @@ spotless = { id = "com.diffplug.spotless", version = "5.14.2" }
 asm = "org.ow2.asm:asm:9.2"
 autoCommon = "com.google.auto:auto-common:1.1"
 autoService = { module = "com.google.auto.service:auto-service-annotations", version.ref = "autoService" }
-autoService-processor = { module = "com.google.auto.service:auto-service", version.ref = "autoService" }
-guava = { module = "com.google.guava:guava", version = "30.1.1-jre" }
-incap = { module = "net.ltgt.gradle.incap:incap", version.ref = "incap" }
-incap-processor = { module = "net.ltgt.gradle.incap:incap-processor", version.ref = "incap" }
+autoService-ksp = "dev.zacsweers.autoservice:auto-service-ksp:1.0.0"
+guava = "com.google.guava:guava:30.1.1-jre"
 jsr305 = "com.google.code.findbugs:jsr305:3.0.2"
 kotlin-compilerEmbeddable = { module = "org.jetbrains.kotlin:kotlin-compiler-embeddable", version.ref = "kotlin" }
 kotlin-reflect = { module = "org.jetbrains.kotlin:kotlin-reflect", version.ref = "kotlin" }
 kotlinpoet = { module = "com.squareup:kotlinpoet", version.ref = "kotlinpoet" }
 kotlinpoet-metadata = { module = "com.squareup:kotlinpoet-metadata", version.ref = "kotlinpoet" }
+kotlinpoet-ksp = { module = "com.squareup:kotlinpoet-ksp", version.ref = "kotlinpoet" }
 kotlinxMetadata = "org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.3.0"
+ksp = { module = "com.google.devtools.ksp:symbol-processing", version.ref = "ksp" }
+ksp-api = { module = "com.google.devtools.ksp:symbol-processing-api", version.ref = "ksp" }
 okio = "com.squareup.okio:okio:2.10.0"
 
 # Test libs
 assertj = "org.assertj:assertj-core:3.11.1"
 junit = "junit:junit:4.13.2"
 kotlinCompileTesting = { module = "com.github.tschuchortdev:kotlin-compile-testing", version.ref = "kotlinCompileTesting" }
+kotlinCompileTesting-ksp = { module = "com.github.tschuchortdev:kotlin-compile-testing-ksp", version.ref ="kotlinCompileTesting" }
 truth = "com.google.truth:truth:1.1.3"

kotlin/codegen/build.gradle.kts

@@ -20,7 +20,7 @@ import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
   kotlin("jvm")
-  kotlin("kapt")
+  alias(libs.plugins.ksp)
   id("com.vanniktech.maven.publish")
   alias(libs.plugins.mavenShadow)
 }
@@ -31,12 +31,12 @@ tasks.withType<KotlinCompile>().configureEach {
     freeCompilerArgs += listOf(
       "-Xopt-in=kotlin.RequiresOptIn",
       "-Xopt-in=com.squareup.kotlinpoet.metadata.KotlinPoetMetadataPreview",
+      "-Xopt-in=com.squareup.kotlinpoet.ksp.KotlinPoetKspPreview",
     )
   }
 }
 
 tasks.withType<Test>().configureEach {
-  // For kapt to work with kotlin-compile-testing
   jvmArgs(
     "--add-opens=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED",
     "--add-opens=jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED",
@@ -47,17 +47,15 @@ tasks.withType<Test>().configureEach {
     "--add-opens=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED",
     "--add-opens=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED",
     "--add-opens=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED",
-    "--add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED",
+    "--add-opens=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED"
   )
 }
 
 val shade: Configuration = configurations.maybeCreate("compileShaded")
 configurations.getByName("compileOnly").extendsFrom(shade)
 dependencies {
-  // Use `api` because kapt will not resolve `runtime` dependencies without it, only `compile`
-  // https://youtrack.jetbrains.com/issue/KT-41702
-  api(project(":moshi"))
-  api(kotlin("reflect"))
+  implementation(project(":moshi"))
+  implementation(kotlin("reflect"))
   shade(libs.kotlinxMetadata) {
     exclude(group = "org.jetbrains.kotlin", module = "kotlin-stdlib")
   }
@@ -67,16 +65,30 @@ dependencies {
     exclude(group = "com.squareup", module = "kotlinpoet")
     exclude(group = "com.google.guava")
   }
-  api(libs.guava)
-  api(libs.asm)
+  shade(libs.kotlinpoet.ksp) {
+    exclude(group = "org.jetbrains.kotlin")
+    exclude(group = "com.squareup", module = "kotlinpoet")
+  }
+  implementation(libs.guava)
+  implementation(libs.asm)
+
+  implementation(libs.autoService)
+  ksp(libs.autoService.ksp)
 
-  api(libs.autoService)
-  kapt(libs.autoService.processor)
-  api(libs.incap)
-  kapt(libs.incap.processor)
+  // KSP deps
+  compileOnly(libs.ksp)
+  compileOnly(libs.ksp.api)
+  compileOnly(libs.kotlin.compilerEmbeddable)
+  // Always force the latest KSP version to match the one we're compiling against
+  testImplementation(libs.ksp)
+  testImplementation(libs.kotlin.compilerEmbeddable)
+  testImplementation(libs.kotlinCompileTesting.ksp)
 
   // Copy these again as they're not automatically included since they're shaded
+  testImplementation(project(":moshi"))
+  testImplementation(kotlin("reflect"))
   testImplementation(libs.kotlinpoet.metadata)
+  testImplementation(libs.kotlinpoet.ksp)
   testImplementation(libs.junit)
   testImplementation(libs.truth)
   testImplementation(libs.kotlinCompileTesting)

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/api/Options.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2021 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.squareup.moshi.kotlin.codegen.api
+
+import com.squareup.kotlinpoet.ClassName
+
+internal object Options {
+  /**
+   * This processing option can be specified to have a `@Generated` annotation
+   * included in the generated code. It is not encouraged unless you need it for static analysis
+   * reasons and not enabled by default.
+   *
+   * Note that this can only be one of the following values:
+   *   * `"javax.annotation.processing.Generated"` (JRE 9+)
+   *   * `"javax.annotation.Generated"` (JRE <9)
+   */
+  const val OPTION_GENERATED: String = "moshi.generated"
+
+  /**
+   * This boolean processing option can disable proguard rule generation.
+   * Normally, this is not recommended unless end-users build their own JsonAdapter look-up tool.
+   * This is enabled by default.
+   */
+  const val OPTION_GENERATE_PROGUARD_RULES: String = "moshi.generateProguardRules"
+
+  val POSSIBLE_GENERATED_NAMES = arrayOf(
+    ClassName("javax.annotation.processing", "Generated"),
+    ClassName("javax.annotation", "Generated")
+  ).associateBy { it.canonicalName }
+}

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/api/ProguardRules.kt

@@ -16,9 +16,6 @@
 package com.squareup.moshi.kotlin.codegen.api
 
 import com.squareup.kotlinpoet.ClassName
-import javax.annotation.processing.Filer
-import javax.lang.model.element.Element
-import javax.tools.StandardLocation
 
 /**
  * Represents a proguard configuration for a given spec. This covers three main areas:
@@ -42,16 +39,11 @@ internal data class ProguardConfig(
   val targetConstructorParams: List<String>,
   val qualifierProperties: Set<QualifierAdapterProperty>
 ) {
-  private val outputFile = "META-INF/proguard/moshi-${targetClass.canonicalName}.pro"
-
-  /** Writes this to `filer`. */
-  fun writeTo(filer: Filer, vararg originatingElements: Element) {
-    filer.createResource(StandardLocation.CLASS_OUTPUT, "", outputFile, *originatingElements)
-      .openWriter()
-      .use(::writeTo)
+  fun outputFilePathWithoutExtension(canonicalName: String): String {
+    return "META-INF/proguard/moshi-$canonicalName"
   }
 
-  private fun writeTo(out: Appendable): Unit = out.run {
+  fun writeTo(out: Appendable): Unit = out.run {
     //
     // -if class {the target class}
     // -keepnames class {the target class}

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/api/kotlintypes.kt

@@ -217,8 +217,12 @@ internal fun List<TypeName>.toTypeVariableResolver(
     // replacement later that may add bounds referencing this.
     val id = typeVar.name
     parametersMap[id] = TypeVariableName(id)
+  }
+
+  for (typeVar in this) {
+    check(typeVar is TypeVariableName)
     // Now replace it with the full version.
-    parametersMap[id] = typeVar.deepCopy(null) { it.stripTypeVarVariance(resolver) }
+    parametersMap[typeVar.name] = typeVar.deepCopy(null) { it.stripTypeVarVariance(resolver) }
   }
 
   return resolver

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/api/typeAliasUnwrapping.kt

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2021 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.squareup.moshi.kotlin.codegen.api
+
+import com.squareup.kotlinpoet.AnnotationSpec
+import com.squareup.kotlinpoet.ClassName
+import com.squareup.kotlinpoet.LambdaTypeName
+import com.squareup.kotlinpoet.ParameterizedTypeName
+import com.squareup.kotlinpoet.TypeName
+import com.squareup.kotlinpoet.TypeVariableName
+import com.squareup.kotlinpoet.WildcardTypeName
+import com.squareup.kotlinpoet.tag
+import com.squareup.kotlinpoet.tags.TypeAliasTag
+import java.util.TreeSet
+
+internal fun TypeName.unwrapTypeAliasReal(): TypeName {
+  return tag<TypeAliasTag>()?.abbreviatedType?.let { unwrappedType ->
+    // If any type is nullable, then the whole thing is nullable
+    var isAnyNullable = isNullable
+    // Keep track of all annotations across type levels. Sort them too for consistency.
+    val runningAnnotations = TreeSet<AnnotationSpec>(compareBy { it.toString() }).apply {
+      addAll(annotations)
+    }
+    val nestedUnwrappedType = unwrappedType.unwrapTypeAlias()
+    runningAnnotations.addAll(nestedUnwrappedType.annotations)
+    isAnyNullable = isAnyNullable || nestedUnwrappedType.isNullable
+    nestedUnwrappedType.copy(nullable = isAnyNullable, annotations = runningAnnotations.toList())
+  } ?: this
+}
+
+internal fun TypeName.unwrapTypeAlias(): TypeName {
+  return when (this) {
+    is ClassName -> unwrapTypeAliasReal()
+    is ParameterizedTypeName -> {
+      if (TypeAliasTag::class in tags) {
+        unwrapTypeAliasReal()
+      } else {
+        deepCopy(TypeName::unwrapTypeAlias)
+      }
+    }
+    is TypeVariableName -> {
+      if (TypeAliasTag::class in tags) {
+        unwrapTypeAliasReal()
+      } else {
+        deepCopy(transform = TypeName::unwrapTypeAlias)
+      }
+    }
+    is WildcardTypeName -> {
+      if (TypeAliasTag::class in tags) {
+        unwrapTypeAliasReal()
+      } else {
+        deepCopy(TypeName::unwrapTypeAlias)
+      }
+    }
+    is LambdaTypeName -> {
+      if (TypeAliasTag::class in tags) {
+        unwrapTypeAliasReal()
+      } else {
+        deepCopy(TypeName::unwrapTypeAlias)
+      }
+    }
+    else -> throw UnsupportedOperationException("Type '${javaClass.simpleName}' is illegal. Only classes, parameterized types, wildcard types, or type variables are allowed.")
+  }
+}