Fix subtype checking for Java types.

Compiler subtype checking does not convert Java types to Kotlin types, while getting super types from a java type does the conversion, therefore resulting in subtype checking for Java types to fail.
Check if candidate super type is a Java type, convert to Kotlin type for subtype checking.
Potentially needs an ultimate fix in compiler for subtype checking.

1 files changed, 72 insertions, 0 deletions

diff --git a/test-utils/src/main/kotlin/com/google/devtools/ksp/processor/JavaSubtypeProcessor.kt b/test-utils/src/main/kotlin/com/google/devtools/ksp/processor/JavaSubtypeProcessor.kt
new file mode 100644
index 00000000..6f220897
--- /dev/null
+++ b/test-utils/src/main/kotlin/com/google/devtools/ksp/processor/JavaSubtypeProcessor.kt
@@ -0,0 +1,72 @@
+package com.google.devtools.ksp.processor
+
+import com.google.devtools.ksp.KspExperimental
+import com.google.devtools.ksp.getClassDeclarationByName
+import com.google.devtools.ksp.getJavaClassByName
+import com.google.devtools.ksp.processing.Resolver
+import com.google.devtools.ksp.symbol.KSAnnotated
+import com.google.devtools.ksp.symbol.KSPropertyDeclaration
+import com.google.devtools.ksp.symbol.Variance
+
+class JavaSubtypeProcessor : AbstractTestProcessor() {
+    var isOk = true
+    override fun toResult(): List<String> {
+        return listOf(isOk.toString())
+    }
+
+    @OptIn(KspExperimental::class)
+    override fun process(resolver: Resolver): List<KSAnnotated> {
+        val javaCollection = resolver.getJavaClassByName("kotlin.collections.Collection")!!.asStarProjectedType()
+        val javaSet = resolver.getJavaClassByName("kotlin.collections.Set")!!.asStarProjectedType()
+        val ktCollection = resolver.getClassDeclarationByName("kotlin.collections.Collection")!!.asStarProjectedType()
+        val ktSet = resolver.getClassDeclarationByName("kotlin.collections.Set")!!.asStarProjectedType()
+        val javaCollectionRef = resolver.createKSTypeReferenceFromKSType(javaCollection)
+        val ktCollectionRef = resolver.createKSTypeReferenceFromKSType(ktCollection)
+        val javaSetRef = resolver.createKSTypeReferenceFromKSType(javaSet)
+        val ktSetRef = resolver.createKSTypeReferenceFromKSType(ktSet)
+        val javaSetOfJavaSet = javaSet.replace(listOf(resolver.getTypeArgument(javaSetRef, Variance.INVARIANT)))
+        val javaSetOfKtSet = javaSet.replace(listOf(resolver.getTypeArgument(ktSetRef, Variance.INVARIANT)))
+        val ktSetOfJavaSet = ktSet.replace(listOf(resolver.getTypeArgument(javaSetRef, Variance.INVARIANT)))
+        val ktSetOfKtSet = ktSet.replace(listOf(resolver.getTypeArgument(ktSetRef, Variance.INVARIANT)))
+        val javaCollectionOfJavaSet = javaCollection
+            .replace(listOf(resolver.getTypeArgument(javaSetRef, Variance.INVARIANT)))
+        val javaCollectionOfKtSet = javaCollection
+            .replace(listOf(resolver.getTypeArgument(ktSetRef, Variance.INVARIANT)))
+        val ktCollectionOfJavaSet = ktCollection
+            .replace(listOf(resolver.getTypeArgument(javaSetRef, Variance.INVARIANT)))
+        val ktCollectionOfKtSet = ktCollection
+            .replace(listOf(resolver.getTypeArgument(ktSetRef, Variance.INVARIANT)))
+        val ktCollectionOfJavaCollection = ktCollection
+            .replace(listOf(resolver.getTypeArgument(javaCollectionRef, Variance.INVARIANT)))
+        val javaSetOfKtCollection = javaSet
+            .replace(listOf(resolver.getTypeArgument(ktCollectionRef, Variance.INVARIANT)))
+        val container = resolver.getClassDeclarationByName("Container")!!
+        val strRef = resolver.getTypeArgument(
+            (container.declarations.single { it.simpleName.asString() == "str" } as KSPropertyDeclaration).type,
+            Variance.INVARIANT
+        )
+        val javaStrCollection = javaCollection.replace(listOf(strRef))
+        val javaStrSet = javaSet.replace(listOf(strRef))
+        isOk = isOk && javaCollection.isAssignableFrom(javaSet)
+        isOk = isOk && javaCollection.isAssignableFrom(javaStrCollection)
+        isOk = isOk && !javaStrCollection.isAssignableFrom(javaCollection)
+        isOk = isOk && !javaStrSet.isAssignableFrom(javaStrCollection)
+        isOk = isOk && javaStrCollection.isAssignableFrom(javaStrSet)
+        isOk = isOk && javaSet.isAssignableFrom(javaStrSet)
+        isOk = isOk && javaCollection.isAssignableFrom(ktCollection)
+        isOk = isOk && ktCollection.isAssignableFrom(javaCollection)
+        isOk = isOk && javaSetOfJavaSet.isAssignableFrom(ktSetOfJavaSet)
+        isOk = isOk && ktSetOfJavaSet.isAssignableFrom(javaSetOfJavaSet)
+        isOk = isOk && javaSetOfJavaSet.isAssignableFrom(javaSetOfKtSet)
+        isOk = isOk && javaSetOfKtSet.isAssignableFrom(javaSetOfJavaSet)
+        isOk = isOk && ktSetOfKtSet.isAssignableFrom(ktSetOfJavaSet)
+        isOk = isOk && ktSetOfJavaSet.isAssignableFrom(ktSetOfKtSet)
+        isOk = isOk && javaCollectionOfJavaSet.isAssignableFrom(ktCollectionOfJavaSet)
+        isOk = isOk && ktCollectionOfJavaSet.isAssignableFrom(javaCollectionOfJavaSet)
+        isOk = isOk && javaCollectionOfKtSet.isAssignableFrom(ktCollectionOfKtSet)
+        isOk = isOk && javaCollectionOfKtSet.isAssignableFrom(ktCollectionOfJavaSet)
+        isOk = isOk && ktCollectionOfJavaCollection.isAssignableFrom(javaSetOfKtCollection)
+        isOk = isOk && !javaSetOfKtCollection.isAssignableFrom(ktCollectionOfJavaCollection)
+        return emptyList()
+    }
+}