Kapt: Clear stubs directory on non-incremental stub generation (KT-21735)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/KaptGenerateStubsTask.kt

@@ -21,6 +21,7 @@ import org.gradle.api.tasks.*
 import org.gradle.api.tasks.incremental.IncrementalTaskInputs
 import org.jetbrains.kotlin.cli.common.arguments.K2JVMCompilerArguments
 import org.jetbrains.kotlin.gradle.plugin.kotlinDebug
+import org.jetbrains.kotlin.gradle.plugin.kotlinWarn
 import org.jetbrains.kotlin.gradle.tasks.FilteringSourceRootsContainer
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 import org.jetbrains.kotlin.incremental.ChangedFiles
@@ -72,6 +73,16 @@ open class KaptGenerateStubsTask : KotlinCompile() {
         args.destinationAsFile = this.destinationDir
     }
 
+    override fun clearOutputsBeforeNonIncrementalBuild() {
+        super.clearOutputsBeforeNonIncrementalBuild()
+
+        if (!stubsDir.deleteRecursively()) {
+            logger.kotlinWarn("Could not delete $stubsDir")
+        }
+
+        stubsDir.mkdirs()
+    }
+
     override fun execute(inputs: IncrementalTaskInputs) {
         val sourceRoots = kotlinCompileTask.getSourceRoots()
         val allKotlinSources = sourceRoots.kotlinSourceFiles

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/tasks/Tasks.kt

@@ -339,6 +339,13 @@ open class KotlinCompile : AbstractKotlinCompile<K2JVMCompilerArguments>(), Kotl
     @Internal
     override fun getSourceRoots() = SourceRoots.ForJvm.create(getSource(), sourceRootsContainer)
 
+    protected open fun clearOutputsBeforeNonIncrementalBuild() {
+        logger.kotlinDebug { "Removing all kotlin classes in $destinationDir" }
+
+        destinationDir.deleteRecursively()
+        destinationDir.mkdirs()
+    }
+
     override fun callCompiler(args: K2JVMCompilerArguments, sourceRoots: SourceRoots, changedFiles: ChangedFiles) {
         sourceRoots as SourceRoots.ForJvm
 
@@ -368,9 +375,7 @@ open class KotlinCompile : AbstractKotlinCompile<K2JVMCompilerArguments>(), Kotl
         }
 
         if (!incremental) {
-            logger.kotlinDebug { "Removing all kotlin classes in $destinationDir" }
-            destinationDir.deleteRecursively()
-            destinationDir.mkdirs()
+            clearOutputsBeforeNonIncrementalBuild()
         }
 
         try {