Allow additional types in @KotlinCoreEnvironmentTest annotation

detekt-test-utils/api/detekt-test-utils.api

@@ -48,6 +48,7 @@ public final class io/github/detekt/test/utils/StringPrintStream : java/io/Print
 
 public abstract interface annotation class io/gitlab/arturbosch/detekt/rules/KotlinCoreEnvironmentTest : java/lang/annotation/Annotation {
 	public abstract fun additionalJavaSourcePaths ()[Ljava/lang/String;
+	public abstract fun additionalTypes ()[Ljava/lang/Class;
 }
 
 public final class io/gitlab/arturbosch/detekt/rules/KotlinEnvironmentTestSetupKt {

detekt-test-utils/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/KotlinEnvironmentTestSetup.kt

@@ -12,6 +12,7 @@ import org.spekframework.spek2.dsl.Root
 import org.spekframework.spek2.lifecycle.CachingMode
 import java.io.File
 import java.nio.file.Path
+import kotlin.reflect.KClass
 
 @Deprecated(
     "This is specific to Spek and will be removed in a future release. Documentation has been updated to " +
@@ -33,6 +34,7 @@ fun Root.setupKotlinEnvironment(additionalJavaSourceRootPath: Path? = null) {
 @Target(AnnotationTarget.CLASS)
 @ExtendWith(KotlinEnvironmentResolver::class)
 annotation class KotlinCoreEnvironmentTest(
+    val additionalTypes: Array<KClass<out Any>> = [],
     val additionalJavaSourcePaths: Array<String> = []
 )
 
@@ -48,7 +50,10 @@ internal class KotlinEnvironmentResolver : ParameterResolver {
     override fun resolveParameter(parameterContext: ParameterContext, extensionContext: ExtensionContext): Any {
         val closeableWrapper = extensionContext.wrapper
             ?: CloseableWrapper(
-                createEnvironment(additionalJavaSourceRootPaths = extensionContext.additionalJavaSourcePaths())
+                createEnvironment(
+                    additionalJavaSourceRootPaths = extensionContext.additionalJavaSourcePaths(),
+                    additionalRootPaths = extensionContext.additionalRootPaths().toList()
+                )
             ).also { extensionContext.wrapper = it }
         return closeableWrapper.wrapper.env
     }
@@ -61,6 +66,12 @@ internal class KotlinEnvironmentResolver : ParameterResolver {
                 .find { it is KotlinCoreEnvironmentTest } as? KotlinCoreEnvironmentTest ?: return emptyList()
             return annotation.additionalJavaSourcePaths.map { resourceAsPath(it).toFile() }
         }
+
+        private fun ExtensionContext.additionalRootPaths(): Set<File> {
+            val annotation = requiredTestClass.annotations
+                .find { it is KotlinCoreEnvironmentTest } as? KotlinCoreEnvironmentTest ?: return emptySet()
+            return annotation.additionalTypes.map { File(it.java.protectionDomain.codeSource.location.path) }.toSet()
+        }
     }
 
     private class CloseableWrapper(val wrapper: KotlinCoreEnvironmentWrapper) :

detekt-test-utils/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/KotlinCoreEnvironmentTestSpec.kt

@@ -0,0 +1,86 @@
+package io.gitlab.arturbosch.detekt.rules
+
+import io.github.detekt.test.utils.compileContentForTest
+import org.assertj.core.api.AbstractAssert
+import org.assertj.core.api.Assertions.assertThat
+import org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment
+import org.jetbrains.kotlin.cli.jvm.compiler.NoScopeRecordCliBindingTrace
+import org.jetbrains.kotlin.cli.jvm.compiler.TopDownAnalyzerFacadeForJVM
+import org.jetbrains.kotlin.psi.KtClass
+import org.jetbrains.kotlin.psi.KtFile
+import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameOrNull
+import org.jetbrains.kotlin.resolve.descriptorUtil.getAllSuperclassesWithoutAny
+import org.jetbrains.kotlin.resolve.lazy.declarations.FileBasedDeclarationProviderFactory
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+
+internal class KotlinCoreEnvironmentTestSpec {
+
+    private val code = """
+        import org.assertj.core.api.AbstractAssert
+
+        class CustomAssert(actual: String) : AbstractAssert<CustomAssert, String>(actual, CustomAssert::class.java)
+    """.trimIndent()
+
+    @Nested
+    @KotlinCoreEnvironmentTest
+    inner class `Without additional types`(private val env: KotlinCoreEnvironment) {
+        @Test
+        fun `no assertj api are available on classpath`() {
+            val actual = code.compileAndGetSuperTypes(env)
+
+            assertThat(actual).isEmpty()
+        }
+    }
+
+    @Nested
+    inner class `With additional types` {
+        val expected = listOf("org.assertj.core.api.AbstractAssert")
+
+        @Nested
+        @KotlinCoreEnvironmentTest(additionalTypes = [AbstractAssert::class])
+        inner class `Only addiontial types`(private val env: KotlinCoreEnvironment) {
+            @Test
+            fun `types from detekt api are available on classpath`() {
+                val actual = code.compileAndGetSuperTypes(env)
+
+                assertThat(actual).isEqualTo(expected)
+            }
+        }
+
+        @Nested
+        @KotlinCoreEnvironmentTest(additionalTypes = [AbstractAssert::class, CharRange::class])
+        inner class `Also types that are already available`(private val env: KotlinCoreEnvironment) {
+            @Test
+            fun `no conflict if types are added multiple times`() {
+                val actual = code.compileAndGetSuperTypes(env)
+
+                assertThat(actual).isEqualTo(expected)
+            }
+        }
+    }
+
+    private fun String.compileAndGetSuperTypes(env: KotlinCoreEnvironment): List<String> {
+        val ktFile = compileContentForTest(this)
+        val ktClass = ktFile.findChildByClass(KtClass::class.java)!!
+        val bindingContext = env.getContextForPaths(listOf(ktFile))
+
+        return bindingContext[BindingContext.CLASS, ktClass]
+            ?.getAllSuperclassesWithoutAny()
+            ?.map { checkNotNull(it.fqNameOrNull()).toString() }
+            .orEmpty()
+    }
+}
+
+// copied from KotlinCoreEnvironmentExtensions.kt
+// this is not ideal
+private fun KotlinCoreEnvironment.getContextForPaths(paths: List<KtFile>): BindingContext =
+    TopDownAnalyzerFacadeForJVM.analyzeFilesWithJavaIntegration(
+        this.project,
+        paths,
+        NoScopeRecordCliBindingTrace(),
+        this.configuration,
+        this::createPackagePartProvider,
+        ::FileBasedDeclarationProviderFactory
+    ).bindingContext