Switch to kotlin-compile-testing for JsonClassCodegenProcessorTe… (#928)

* Add kotlin-compile-testing dependency

* Add Okio dependency to tests to match kotlin-compile-testing

Without this, Okio.sink() fails to resolve at runtime

* Try converting privateConstructor() to kotlin-compile-testing

* Space

* Update to 1.2.2

* Use new kotlin source file API

* Use temporaryFolder as workingDir

* Extract prepareCompilation helper method

This allows for modifying the compilation with extra bits as needed

* Migrate tests entirely to new API

* Remove incorrect error message

This passed before, but was picked up in https://github.com/square/moshi/pull/903 before and observed to be incorrect.

* Remove custom kotlin compiler implementations

* Add an OK exit code test

This wasn't possible before!

* Remove jitpack dependency now that it's on mavencentral

* Move versions to parent pom

* Fix new test from rebase

kotlin/codegen/pom.xml

@@ -25,7 +25,7 @@
     <dependency>
       <groupId>com.squareup</groupId>
       <artifactId>kotlinpoet</artifactId>
-      <version>1.3.0</version>
+      <version>${kotlinpoet.version}</version>
     </dependency>
     <dependency>
       <groupId>net.ltgt.gradle.incap</groupId>
@@ -37,12 +37,12 @@
     <dependency>
       <groupId>com.google.auto</groupId>
       <artifactId>auto-common</artifactId>
-      <version>0.10</version>
+      <version>${auto-common.version}</version>
     </dependency>
     <dependency>
       <groupId>com.google.auto.service</groupId>
       <artifactId>auto-service-annotations</artifactId>
-      <version>${autoservice.version}</version>
+      <version>${auto-service.version}</version>
       <scope>provided</scope>
       <optional>true</optional>
     </dependency>
@@ -56,32 +56,31 @@
       <artifactId>assertj-core</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.google.truth</groupId>
+      <artifactId>truth</artifactId>
+      <version>${truth.version}</version>
+      <scope>test</scope>
+    </dependency>
 
     <!--
-      The Kotlin compiler must be near the end of the list because its .jar file includes an
+      The Kotlin compiler usage must be near the end of the list because its .jar file includes an
       obsolete version of Guava!
     -->
-    <dependency>
-      <groupId>org.jetbrains.kotlin</groupId>
-      <artifactId>kotlin-compiler-embeddable</artifactId>
-      <scope>test</scope>
-    </dependency>
-    <dependency>
-      <groupId>org.jetbrains.kotlin</groupId>
-      <artifactId>kotlin-annotation-processing-embeddable</artifactId>
-      <scope>test</scope>
-    </dependency>
     <dependency>
       <groupId>me.eugeniomarletti.kotlin.metadata</groupId>
       <artifactId>kotlin-metadata</artifactId>
     </dependency>
-    <!--
-      Though we don't use compile-testing, including it is a convenient way to get tools.jar on the
-      classpath. This dependency is required by kapt3.
-    -->
     <dependency>
-      <groupId>com.google.testing.compile</groupId>
-      <artifactId>compile-testing</artifactId>
+      <groupId>com.github.tschuchortdev</groupId>
+      <artifactId>kotlin-compile-testing</artifactId>
+      <version>${kotlin-compile-testing.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.squareup.okio</groupId>
+      <artifactId>okio</artifactId>
+      <version>${okio2.version}</version>
       <scope>test</scope>
     </dependency>
   </dependencies>
@@ -111,7 +110,7 @@
                 <annotationProcessorPath>
                   <groupId>com.google.auto.service</groupId>
                   <artifactId>auto-service</artifactId>
-                  <version>${autoservice.version}</version>
+                  <version>${auto-service.version}</version>
                 </annotationProcessorPath>
                 <annotationProcessorPath>
                   <groupId>net.ltgt.gradle.incap</groupId>

kotlin/codegen/src/test/java/com/squareup/moshi/kotlin/codegen/JsonClassCodegenProcessorTest.kt

@@ -15,384 +15,352 @@
  */
 package com.squareup.moshi.kotlin.codegen
 
+import com.tschuchort.compiletesting.KotlinCompilation
+import com.tschuchort.compiletesting.SourceFile
+import com.tschuchort.compiletesting.SourceFile.Companion.kotlin
 import org.assertj.core.api.Assertions.assertThat
-import org.jetbrains.kotlin.cli.common.ExitCode
 import org.junit.Ignore
 import org.junit.Rule
 import org.junit.Test
 import org.junit.rules.TemporaryFolder
-import javax.annotation.processing.Processor
 
 /** Execute kotlinc to confirm that either files are generated or errors are printed. */
 class JsonClassCodegenProcessorTest {
   @Rule @JvmField var temporaryFolder: TemporaryFolder = TemporaryFolder()
 
   @Test fun privateConstructor() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class PrivateConstructor private constructor(var a: Int, var b: Int) {
-        |  fun a() = a
-        |  fun b() = b
-        |  companion object {
-        |    fun newInstance(a: Int, b: Int) = PrivateConstructor(a, b)
-        |  }
-        |}
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("constructor is not internal or public")
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          class PrivateConstructor private constructor(var a: Int, var b: Int) {
+            fun a() = a
+            fun b() = b
+            companion object {
+              fun newInstance(a: Int, b: Int) = PrivateConstructor(a, b)
+            }
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("constructor is not internal or public")
   }
 
   @Test fun privateConstructorParameter() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class PrivateConstructorParameter(private var a: Int)
-        |""".trimMargin())
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("property a is not visible")
+          @JsonClass(generateAdapter = true)
+          class PrivateConstructorParameter(private var a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("property a is not visible")
   }
 
   @Test fun privateProperties() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class PrivateProperties {
-        |  private var a: Int = -1
-        |  private var b: Int = -1
-        |}
-        |""".trimMargin())
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("property a is not visible")
+          @JsonClass(generateAdapter = true)
+          class PrivateProperties {
+            private var a: Int = -1
+            private var b: Int = -1
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("property a is not visible")
   }
 
   @Test fun interfacesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |interface Interface
-        |""".trimMargin())
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+          @JsonClass(generateAdapter = true)
+          interface Interface
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to Interface: must be a Kotlin class")
   }
 
-  @Test fun abstractClassesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |abstract class AbstractClass(val a: Int)
-        |""".trimMargin())
+  @Test fun interfacesDoNotErrorWhenGeneratorNotSet() {
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+          @JsonClass(generateAdapter = true, generator="customGenerator")
+          interface Interface
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.OK)
+  }
+
+  @Test fun abstractClassesNotSupported() {
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          abstract class AbstractClass(val a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to AbstractClass: must not be abstract")
   }
 
   @Test fun sealedClassesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |sealed class SealedClass(val a: Int)
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+  
+          @JsonClass(generateAdapter = true)
+          sealed class SealedClass(val a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to SealedClass: must not be sealed")
   }
 
   @Test fun innerClassesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |class Outer {
-        |  @JsonClass(generateAdapter = true)
-        |  inner class InnerClass(val a: Int)
-        |}
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          class Outer {
+            @JsonClass(generateAdapter = true)
+            inner class InnerClass(val a: Int)
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to Outer.InnerClass: must not be an inner class")
   }
 
   @Test fun enumClassesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |enum class KotlinEnum {
-        |  A, B
-        |}
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          enum class KotlinEnum {
+            A, B
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass with 'generateAdapter = \"true\"' can't be applied to KotlinEnum: code gen for enums is not supported or necessary")
   }
 
   // Annotation processors don't get called for local classes, so we don't have the opportunity to
   // print an error message. Instead local classes will fail at runtime.
-  @Ignore
-  @Test fun localClassesNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |fun outer() {
-        |  @JsonClass(generateAdapter = true)
-        |  class LocalClass(val a: Int)
-        |}
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+  @Ignore @Test fun localClassesNotSupported() {
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          fun outer() {
+            @JsonClass(generateAdapter = true)
+            class LocalClass(val a: Int)
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to LocalClass: must not be local")
   }
 
   @Test fun objectDeclarationsNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |object ObjectDeclaration {
-        |  var a = 5
-        |}
-        |""".trimMargin())
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          object ObjectDeclaration {
+            var a = 5
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to ObjectDeclaration: must be a Kotlin class")
   }
 
   @Test fun objectExpressionsNotSupported() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |val expression = object : Any() {
-        |  var a = 5
-        |}
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          val expression = object : Any() {
+            var a = 5
+          }
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: @JsonClass can't be applied to expression\$annotations(): must be a Kotlin class")
   }
 
   @Test fun requiredTransientConstructorParameterFails() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class RequiredTransientConstructorParameter(@Transient var a: Int)
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          class RequiredTransientConstructorParameter(@Transient var a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: No default value for transient property a")
   }
 
   @Test fun nonPropertyConstructorParameter() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class NonPropertyConstructorParameter(a: Int, val b: Int)
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          import com.squareup.moshi.JsonClass
+          @JsonClass(generateAdapter = true)
+          class NonPropertyConstructorParameter(a: Int, val b: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains(
         "error: No property for required constructor parameter a")
   }
 
   @Test fun badGeneratedAnnotation() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.kaptArgs[JsonClassCodegenProcessor.OPTION_GENERATED] = "javax.annotation.GeneratedBlerg"
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |data class Foo(val a: Int)
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains(
+    val result = prepareCompilation(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          
+          @JsonClass(generateAdapter = true)
+          data class Foo(val a: Int)
+          """
+    )).apply {
+      kaptArgs[JsonClassCodegenProcessor.OPTION_GENERATED] = "javax.annotation.GeneratedBlerg"
+    }.compile()
+    assertThat(result.messages).contains(
         "Invalid option value for ${JsonClassCodegenProcessor.OPTION_GENERATED}")
   }
 
   @Test fun multipleErrors() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class Class1(private var a: Int, private var b: Int)
-        |
-        |@JsonClass(generateAdapter = true)
-        |class Class2(private var c: Int)
-        |""".trimMargin())
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("property a is not visible")
-    assertThat(result.systemErr).contains("property b is not visible")
-    assertThat(result.systemErr).contains("property c is not visible")
+          @JsonClass(generateAdapter = true)
+          class Class1(private var a: Int, private var b: Int)
+
+          @JsonClass(generateAdapter = true)
+          class Class2(private var c: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("property a is not visible")
+    assertThat(result.messages).contains("property c is not visible")
   }
 
   @Test fun extendPlatformType() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |import java.util.Date
-        |
-        |@JsonClass(generateAdapter = true)
-        |class ExtendsPlatformClass(var a: Int) : Date()
-        |""".trimMargin())
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          import java.util.Date
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("supertype java.util.Date is not a Kotlin type")
+          @JsonClass(generateAdapter = true)
+          class ExtendsPlatformClass(var a: Int) : Date()
+          """
+    ))
+    assertThat(result.messages).contains("supertype java.util.Date is not a Kotlin type")
   }
 
   @Test fun extendJavaType() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |import com.squareup.moshi.kotlin.codegen.JavaSuperclass
-        |
-        |@JsonClass(generateAdapter = true)
-        |class ExtendsJavaType(var b: Int) : JavaSuperclass()
-        |""".trimMargin())
-
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr)
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          import com.squareup.moshi.kotlin.codegen.JavaSuperclass
+          
+          @JsonClass(generateAdapter = true)
+          class ExtendsJavaType(var b: Int) : JavaSuperclass()
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages)
         .contains("supertype com.squareup.moshi.kotlin.codegen.JavaSuperclass is not a Kotlin type")
   }
 
-  @Test
-  fun nonFieldApplicableQualifier() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |import com.squareup.moshi.JsonQualifier
-        |import kotlin.annotation.AnnotationRetention.RUNTIME
-        |import kotlin.annotation.AnnotationTarget.PROPERTY
-        |import kotlin.annotation.Retention
-        |import kotlin.annotation.Target
-        |
-        |@Retention(RUNTIME)
-        |@Target(PROPERTY)
-        |@JsonQualifier
-        |annotation class UpperCase
-        |
-        |@JsonClass(generateAdapter = true)
-        |class ClassWithQualifier(@UpperCase val a: Int)
-        |""".trimMargin())
+  @Test fun nonFieldApplicableQualifier() {
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          import com.squareup.moshi.JsonQualifier
+          import kotlin.annotation.AnnotationRetention.RUNTIME
+          import kotlin.annotation.AnnotationTarget.PROPERTY
+          import kotlin.annotation.Retention
+          import kotlin.annotation.Target
 
-    val result = call.execute()
-    println(result.systemErr)
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("JsonQualifier @UpperCase must support FIELD target")
+          @Retention(RUNTIME)
+          @Target(PROPERTY)
+          @JsonQualifier
+          annotation class UpperCase
+
+          @JsonClass(generateAdapter = true)
+          class ClassWithQualifier(@UpperCase val a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("JsonQualifier @UpperCase must support FIELD target")
   }
 
-  @Test
-  fun nonRuntimeQualifier() {
-    val call = KotlinCompilerCall(temporaryFolder.root)
-    call.inheritClasspath = true
-    call.addService(Processor::class, JsonClassCodegenProcessor::class)
-    call.addKt("source.kt", """
-        |import com.squareup.moshi.JsonClass
-        |import com.squareup.moshi.JsonQualifier
-        |import kotlin.annotation.AnnotationRetention.BINARY
-        |import kotlin.annotation.AnnotationTarget.FIELD
-        |import kotlin.annotation.AnnotationTarget.PROPERTY
-        |import kotlin.annotation.Retention
-        |import kotlin.annotation.Target
-        |
-        |@Retention(BINARY)
-        |@Target(PROPERTY, FIELD)
-        |@JsonQualifier
-        |annotation class UpperCase
-        |
-        |@JsonClass(generateAdapter = true)
-        |class ClassWithQualifier(@UpperCase val a: Int)
-        |""".trimMargin())
+  @Test fun nonRuntimeQualifier() {
+    val result = compile(kotlin("source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+          import com.squareup.moshi.JsonQualifier
+          import kotlin.annotation.AnnotationRetention.BINARY
+          import kotlin.annotation.AnnotationTarget.FIELD
+          import kotlin.annotation.AnnotationTarget.PROPERTY
+          import kotlin.annotation.Retention
+          import kotlin.annotation.Target
 
-    val result = call.execute()
-    assertThat(result.exitCode).isEqualTo(ExitCode.COMPILATION_ERROR)
-    assertThat(result.systemErr).contains("JsonQualifier @UpperCase must have RUNTIME retention")
+          @Retention(BINARY)
+          @Target(PROPERTY, FIELD)
+          @JsonQualifier
+          annotation class UpperCase
+
+          @JsonClass(generateAdapter = true)
+          class ClassWithQualifier(@UpperCase val a: Int)
+          """
+    ))
+    assertThat(result.exitCode).isEqualTo(KotlinCompilation.ExitCode.COMPILATION_ERROR)
+    assertThat(result.messages).contains("JsonQualifier @UpperCase must have RUNTIME retention")
   }
+
+  private fun prepareCompilation(vararg sourceFiles: SourceFile): KotlinCompilation {
+    return KotlinCompilation()
+        .apply {
+          workingDir = temporaryFolder.root
+          annotationProcessors = listOf(JsonClassCodegenProcessor())
+          inheritClassPath = true
+          sources = sourceFiles.asList()
+          verbose = false
+        }
+  }
+
+  private fun compile(vararg sourceFiles: SourceFile): KotlinCompilation.Result {
+    return prepareCompilation(*sourceFiles).compile()
+  }
+
 }

kotlin/codegen/src/test/java/com/squareup/moshi/kotlin/codegen/KotlinCompilerCall.kt

@@ -1,193 +0,0 @@
-/*
- * Copyright (C) 2018 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
- *
- *      http://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
-
-import com.google.common.collect.LinkedHashMultimap
-import okio.Buffer
-import okio.Okio
-import org.jetbrains.kotlin.cli.common.CLITool
-import org.jetbrains.kotlin.cli.jvm.K2JVMCompiler
-import java.io.File
-import java.io.FileOutputStream
-import java.io.ObjectOutputStream
-import java.io.PrintStream
-import java.net.URLClassLoader
-import java.net.URLDecoder
-import java.util.zip.ZipEntry
-import java.util.zip.ZipOutputStream
-import kotlin.reflect.KClass
-
-/** Prepares an invocation of the Kotlin compiler. */
-class KotlinCompilerCall(var scratchDir: File) {
-  val sourcesDir = File(scratchDir, "sources")
-  val classesDir = File(scratchDir, "classes")
-  val servicesJar = File(scratchDir, "services.jar")
-
-  var inheritClasspath = false
-
-  val args = mutableListOf<String>()
-  val kaptArgs = mutableMapOf<String, String>()
-  val classpath = mutableListOf<String>()
-  val services = LinkedHashMultimap.create<KClass<*>, KClass<*>>()
-
-  /** Adds a source file to be compiled. */
-  fun addKt(path: String, source: String) {
-    val sourceFile = File(sourcesDir, path)
-    sourceFile.parentFile.mkdirs()
-    Okio.buffer(Okio.sink(sourceFile)).use {
-      it.writeUtf8(source)
-    }
-  }
-
-  /** Adds a service like an annotation processor to make available to the compiler. */
-  fun addService(serviceClass: KClass<*>, implementation: KClass<*>) {
-    services.put(serviceClass, implementation)
-  }
-
-  fun execute(): KotlinCompilerResult {
-    val fullArgs = mutableListOf<String>()
-    fullArgs.addAll(args)
-
-    fullArgs.add("-d")
-    fullArgs.add(classesDir.toString())
-
-    val fullClasspath = fullClasspath()
-    if (fullClasspath.isNotEmpty()) {
-      fullArgs.add("-classpath")
-      fullArgs.add(fullClasspath.joinToString(separator = ":"))
-    }
-
-    for (source in sourcesDir.listFiles()) {
-      fullArgs.add(source.toString())
-    }
-
-    fullArgs.addAll(annotationProcessorArgs())
-    if (kaptArgs.isNotEmpty()) {
-      fullArgs.apply {
-        add("-P")
-        add("plugin:org.jetbrains.kotlin.kapt3:apoptions=${encodeOptions(kaptArgs)}")
-      }
-    }
-
-    val systemErrBuffer = Buffer()
-    val oldSystemErr = System.err
-    System.setErr(PrintStream(systemErrBuffer.outputStream()))
-    try {
-      val exitCode = CLITool.doMainNoExit(K2JVMCompiler(), fullArgs.toTypedArray())
-      val systemErr = systemErrBuffer.readUtf8()
-      return KotlinCompilerResult(systemErr, exitCode)
-    } finally {
-      System.setErr(oldSystemErr)
-    }
-  }
-
-  /** Returns arguments necessary to enable and configure kapt3. */
-  private fun annotationProcessorArgs(): List<String> {
-    val kaptSourceDir = File(scratchDir, "kapt/sources")
-    val kaptStubsDir = File(scratchDir, "kapt/stubs")
-
-    return listOf(
-        "-Xplugin=${kapt3Jar()}",
-        "-P", "plugin:org.jetbrains.kotlin.kapt3:sources=$kaptSourceDir",
-        "-P", "plugin:org.jetbrains.kotlin.kapt3:classes=$classesDir",
-        "-P", "plugin:org.jetbrains.kotlin.kapt3:stubs=$kaptStubsDir",
-        "-P", "plugin:org.jetbrains.kotlin.kapt3:apclasspath=$servicesJar",
-        "-P", "plugin:org.jetbrains.kotlin.kapt3:correctErrorTypes=true"
-    )
-  }
-
-  /** Returns the classpath to use when compiling code. */
-  private fun fullClasspath(): List<String> {
-    val result = mutableListOf<String>()
-    result.addAll(classpath)
-
-    // Copy over the classpath of the running application.
-    if (inheritClasspath) {
-      for (classpathFile in classpathFiles()) {
-        result.add(classpathFile.toString())
-      }
-    }
-
-    if (!services.isEmpty) {
-      writeServicesJar()
-      result.add(servicesJar.toString())
-    }
-
-    return result.toList()
-  }
-
-  /**
-   * Generate a .jar file that holds ServiceManager registrations. Necessary because AutoService's
-   * results might not be visible to this test.
-   */
-  private fun writeServicesJar() {
-    ZipOutputStream(FileOutputStream(servicesJar)).use { zipOutputStream ->
-      for (entry in services.asMap()) {
-        zipOutputStream.putNextEntry(
-            ZipEntry("META-INF/services/${entry.key.qualifiedName}"))
-        val serviceFile = Okio.buffer(Okio.sink(zipOutputStream))
-        for (implementation in entry.value) {
-          serviceFile.writeUtf8(implementation.qualifiedName!!)
-          serviceFile.writeUtf8("\n")
-        }
-        serviceFile.emit() // Don't close the entry; that closes the file.
-        zipOutputStream.closeEntry()
-      }
-    }
-  }
-
-  /** Returns the files on the host process' classpath. */
-  private fun classpathFiles(): List<File> {
-    val classLoader = JsonClassCodegenProcessorTest::class.java.classLoader
-    if (classLoader !is URLClassLoader) {
-      throw UnsupportedOperationException("unable to extract classpath from $classLoader")
-    }
-
-    val result = mutableListOf<File>()
-    for (url in classLoader.urLs) {
-      if (url.protocol != "file") {
-        throw UnsupportedOperationException("unable to handle classpath element $url")
-      }
-      result.add(File(URLDecoder.decode(url.path, "UTF-8")))
-    }
-    return result.toList()
-  }
-
-  /** Returns the path to the kotlin-annotation-processing .jar file. */
-  private fun kapt3Jar(): File {
-    for (file in classpathFiles()) {
-      if (file.name.startsWith("kotlin-annotation-processing-embeddable")) return file
-    }
-    throw IllegalStateException("no kotlin-annotation-processing-embeddable jar on classpath:\n  " +
-        "${classpathFiles().joinToString(separator = "\n  ")}}")
-  }
-
-  /**
-   * Base64 encodes a mapping of annotation processor args for kapt, as specified by
-   * https://kotlinlang.org/docs/reference/kapt.html#apjavac-options-encoding
-   */
-  private fun encodeOptions(options: Map<String, String>): String {
-    val buffer = Buffer()
-    ObjectOutputStream(buffer.outputStream()).use { oos ->
-      oos.writeInt(options.size)
-      for ((key, value) in options.entries) {
-        oos.writeUTF(key)
-        oos.writeUTF(value)
-      }
-    }
-    return buffer.readByteString().base64()
-  }
-}

kotlin/codegen/src/test/java/com/squareup/moshi/kotlin/codegen/KotlinCompilerResult.kt

@@ -1,23 +0,0 @@
-/*
- * Copyright (C) 2018 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
- *
- *      http://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
-
-import org.jetbrains.kotlin.cli.common.ExitCode
-
-class KotlinCompilerResult(
-  val systemErr: String,
-  var exitCode: ExitCode
-)

pom.xml

@@ -29,20 +29,25 @@
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <java.version>1.7</java.version>
-    <kotlin.version>1.3.40</kotlin.version>
-    <kotlin-metadata.version>1.4.0</kotlin-metadata.version>
-    <dokka.version>0.9.17</dokka.version>
-    <maven-assembly.version>3.1.0</maven-assembly.version>
-    <incap.version>0.2</incap.version>
-    <autoservice.version>1.0-rc5</autoservice.version>
 
     <!-- Dependencies -->
+    <auto-common.version>0.10</auto-common.version>
+    <auto-service.version>1.0-rc5</auto-service.version>
+    <dokka.version>0.9.17</dokka.version>
+    <incap.version>0.2</incap.version>
     <okio.version>1.16.0</okio.version>
+    <okio2.version>2.1.0</okio2.version>
+    <kotlin.version>1.3.40</kotlin.version>
+    <kotlinpoet.version>1.3.0</kotlinpoet.version>
+    <kotlin-metadata.version>1.4.0</kotlin-metadata.version>
+    <maven-assembly.version>3.1.0</maven-assembly.version>
 
     <!-- Test Dependencies -->
+    <assertj.version>3.11.1</assertj.version>
     <compile-testing.version>0.15</compile-testing.version>
     <junit.version>4.12</junit.version>
-    <assertj.version>3.11.1</assertj.version>
+    <kotlin-compile-testing.version>1.2.2</kotlin-compile-testing.version>
+    <truth.version>1.0</truth.version>
   </properties>
 
   <scm>