Fix issue with KSTypeVarianceResolver with use-site variance
This CL fixes an issue with `KSTypeVarianceResolver` where we were
incorrectly eliding wildcards. The issue was that the logic for
determining the variance of previous type arguments on the stack was
only looking at the declaration site variance and not the use site
variance.
Test: KspTypeNamesGoldenTest.kt
Change-Id: I9deef8cad5f7b52a9612a813fd7805b1e147d6be
diff --git a/room/room-compiler-processing/src/main/java/androidx/room/compiler/processing/ksp/KSTypeVarianceResolver.kt b/room/room-compiler-processing/src/main/java/androidx/room/compiler/processing/ksp/KSTypeVarianceResolver.kt
index ca11a18..338d041 100644
--- a/room/room-compiler-processing/src/main/java/androidx/room/compiler/processing/ksp/KSTypeVarianceResolver.kt
+++ b/room/room-compiler-processing/src/main/java/androidx/room/compiler/processing/ksp/KSTypeVarianceResolver.kt
@@ -177,15 +177,24 @@
val type = type ?: return this
val resolvedType = type.getJavaWildcard(scope)
fun inheritDeclarationSiteVariance(): Boolean {
+ // The variance of previous type arguments on the stack. If the type argument has no
+ // explicit (aka use-site) variance, the type param (aka declaration site) variance is
+ // used.
+ val varianceStack = typeArgStack.indices.map { i ->
+ if (typeArgStack[i].variance != Variance.INVARIANT) {
+ typeArgStack[i].variance
+ } else {
+ typeParamStack[i].variance
+ }
+ }
// Before we check the current variance, we need to check the previous variance in the
// stack to see if they allow us to inherit the current variance, and that logic differs
// depending on the scope.
if (scope.isValOrReturnType()) {
// For val and return type scopes, we don't use the declaration-site variance if
// none of variances in the stack are contravariant.
- if (typeParamStack.indices.none { i ->
- (typeParamStack[i].variance == Variance.CONTRAVARIANT ||
- typeArgStack[i].variance == Variance.CONTRAVARIANT) &&
+ if (varianceStack.indices.none { i ->
+ (varianceStack[i] == Variance.CONTRAVARIANT) &&
// The declaration and use site variance is ignored when using
// @JvmWildcard explicitly on a type.
!typeArgStack[i].hasJvmWildcardAnnotation()
@@ -195,15 +204,14 @@
} else {
// For method parameters and var type scopes, we don't use the declaration-site
// variance if all of the following conditions apply.
- if ( // If the last variance in the type argument stack is not contravariant
- typeArgStack.isNotEmpty() &&
- typeArgStack.last().variance != Variance.CONTRAVARIANT &&
- // And the type parameter stack contains at least one invariant parameter.
- typeParamStack.isNotEmpty() &&
- typeParamStack.any { it.variance == Variance.INVARIANT } &&
+ if ( // If the last variance in the stack is not contravariant
+ varianceStack.isNotEmpty() &&
+ varianceStack.last() != Variance.CONTRAVARIANT &&
+ // And the stack contains at least one invariant parameter.
+ varianceStack.any { it == Variance.INVARIANT } &&
// And the first invariant comes before the last contravariant (if any).
- typeParamStack.indexOfFirst { it.variance == Variance.INVARIANT } >=
- typeParamStack.indexOfLast { it.variance == Variance.CONTRAVARIANT }
+ varianceStack.indexOfFirst { it == Variance.INVARIANT } >=
+ varianceStack.indexOfLast { it == Variance.CONTRAVARIANT }
) {
return false
}
diff --git a/room/room-compiler-processing/src/test/java/androidx/room/compiler/processing/ksp/KspTypeNamesGoldenTest.kt b/room/room-compiler-processing/src/test/java/androidx/room/compiler/processing/ksp/KspTypeNamesGoldenTest.kt
index c793faf..2cf13ff 100644
--- a/room/room-compiler-processing/src/test/java/androidx/room/compiler/processing/ksp/KspTypeNamesGoldenTest.kt
+++ b/room/room-compiler-processing/src/test/java/androidx/room/compiler/processing/ksp/KspTypeNamesGoldenTest.kt
@@ -369,6 +369,15 @@
fun method53(param: MyInlineType): MyInlineType = TODO()
fun method54(param: MyGenericOut<MyInlineType>): MyGenericOut<MyInlineType> = TODO()
fun method55(param: MyGenericIn<MyInlineType>): MyGenericIn<MyInlineType> = TODO()
+ fun method56(
+ param: MyGeneric<out MyGeneric<out MyGenericOut<MyInterface>>>
+ ): MyGeneric<out MyGeneric<out MyGenericOut<MyInterface>>> = TODO()
+ fun method57(
+ param: MyGeneric<out MyGeneric<MyGenericOut<MyInterface>>>
+ ): MyGeneric<out MyGeneric<MyGenericOut<MyInterface>>> = TODO()
+ fun method58(
+ param: MyGeneric<out MyGenericOut<MyGenericOut<MyInterface>>>
+ ): MyGeneric<out MyGenericOut<MyGenericOut<MyInterface>>> = TODO()
}
""".trimIndent()
), listOf("Subject")
