Add regression test for annotation array value type

kotlin-analysis-api/src/test/kotlin/com/google/devtools/ksp/processor/AnnotationArrayValueTypeProcessor.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2026 Google LLC
+ * Copyright 2010-2026 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ *
+ * 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.google.devtools.ksp.processor
+
+import com.google.devtools.ksp.getClassDeclarationByName
+import com.google.devtools.ksp.processing.Resolver
+import com.google.devtools.ksp.symbol.KSAnnotated
+
+class AnnotationArrayValueTypeProcessor : AbstractTestProcessor() {
+    private val results = mutableListOf<String>()
+
+    override fun process(resolver: Resolver): List<KSAnnotated> {
+        logAnnotationArrayValues(resolver, "JavaAnnotated")
+        logAnnotationArrayValues(resolver, "KotlinAnnotated")
+        return emptyList()
+    }
+
+    override fun toResult(): List<String> {
+        return results
+    }
+
+    private fun logAnnotationArrayValues(resolver: Resolver, className: String) {
+        val annotated = resolver.getClassDeclarationByName(className)!!
+        listOf("JavaAnnotation", "KotlinAnnotation").forEach { annotationName ->
+            val annotation = annotated.annotations.single { it.shortName.asString() == annotationName }
+            val argument = annotation.arguments.single()
+            val value = argument.value
+            val argumentName = argument.name?.asString()
+            results.add("$className $annotationName $argumentName is Array<*>: ${value is Array<*>}")
+            results.add("$className $annotationName $argumentName size: ${value.sizeOrNull()}")
+        }
+    }
+
+    private fun Any?.sizeOrNull(): Int? {
+        return when (this) {
+            is Array<*> -> size
+            is Collection<*> -> size
+            else -> null
+        }
+    }
+}

kotlin-analysis-api/src/test/kotlin/com/google/devtools/ksp/test/AAConfiguredUnitTestSuite.kt

@@ -28,6 +28,12 @@ class AAConfiguredUnitTestSuite : KSPUnitTestSuite(experimentalPsiResolution = f
         runTest("$AA_PATH/getSymbolsWithAnnotation/aliasedAnnotation.kt")
     }
 
+    @TestMetadata("annotationArrayValueType.kt")
+    @Test
+    override fun testAnnotationArrayValueType() {
+        runFailingTest("$AA_PATH/annotationArrayValueType.kt")
+    }
+
     @TestMetadata("allUseSiteTargetAppliedToAnnotationList.kt")
     @Test
     override fun testAllUseSiteTargetAppliedToAnnotationList() {

kotlin-analysis-api/src/test/kotlin/com/google/devtools/ksp/test/KSPUnitTestSuite.kt

@@ -152,6 +152,9 @@ abstract class KSPUnitTestSuite(
         runTest("$AA_PATH/annotationWithArrayValue.kt")
     }
 
+    @Bug("https://github.com/google/ksp/issues/3008", BugState.OPEN)
+    abstract fun testAnnotationArrayValueType()
+
     @TestMetadata("annotationWithDefault.kt")
     @Test
     fun testAnnotationWithDefault() {

kotlin-analysis-api/src/test/kotlin/com/google/devtools/ksp/test/PsiConfiguredUnitTestSuite.kt

@@ -28,6 +28,12 @@ class PsiConfiguredUnitTestSuite : KSPUnitTestSuite(experimentalPsiResolution =
         runFailingTest("$AA_PATH/getSymbolsWithAnnotation/aliasedAnnotation.kt")
     }
 
+    @TestMetadata("annotationArrayValueType.kt")
+    @Test
+    override fun testAnnotationArrayValueType() {
+        runFailingTest("$AA_PATH/annotationArrayValueType.kt")
+    }
+
     @TestMetadata("allUseSiteTargetAppliedToAnnotationList.kt")
     @Test
     override fun testAllUseSiteTargetAppliedToAnnotationList() {

kotlin-analysis-api/testData/annotationArrayValueType.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2026 Google LLC
+ * Copyright 2010-2026 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ *
+ * 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.
+ */
+// TEST PROCESSOR: AnnotationArrayValueTypeProcessor
+// EXPECTED:
+// JavaAnnotated JavaAnnotation args is Array<*>: true
+// JavaAnnotated JavaAnnotation args size: 2
+// JavaAnnotated KotlinAnnotation args is Array<*>: true
+// JavaAnnotated KotlinAnnotation args size: 2
+// KotlinAnnotated JavaAnnotation args is Array<*>: true
+// KotlinAnnotated JavaAnnotation args size: 2
+// KotlinAnnotated KotlinAnnotation args is Array<*>: true
+// KotlinAnnotated KotlinAnnotation args size: 2
+// END
+// FILE: JavaAnnotation.java
+public @interface JavaAnnotation {
+    NestedAnnotation[] args();
+}
+
+// FILE: NestedAnnotation.java
+public @interface NestedAnnotation {
+    String value();
+}
+
+// FILE: JavaAnnotated.java
+@JavaAnnotation(args = {@NestedAnnotation(value = "one"), @NestedAnnotation(value = "two")})
+@KotlinAnnotation(args = {@KotlinNestedAnnotation(value = "one"), @KotlinNestedAnnotation(value = "two")})
+class JavaAnnotated {}
+
+// FILE: KotlinAnnotated.kt
+annotation class KotlinAnnotation(val args: Array<KotlinNestedAnnotation>)
+
+annotation class KotlinNestedAnnotation(val value: String)
+
+@JavaAnnotation(args = [NestedAnnotation(value = "one"), NestedAnnotation(value = "two")])
+@KotlinAnnotation(args = [KotlinNestedAnnotation(value = "one"), KotlinNestedAnnotation(value = "two")])
+class KotlinAnnotated