EA-63343 - assert: DescriptorUtils.getClassDescriptorForTypeConstructor

#KT-6835 Fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/AnnotationResolver.java

@@ -154,7 +154,11 @@ public class AnnotationResolver {
             return ErrorUtils.createErrorType("No type reference: " + entryElement.getText());
         }
 
-        return typeResolver.resolveType(scope, typeReference, new BindingTraceContext(), true);
+        JetType type = typeResolver.resolveType(scope, typeReference, new BindingTraceContext(), true);
+        if (!(type.getConstructor().getDeclarationDescriptor() instanceof ClassDescriptor)) {
+            return ErrorUtils.createErrorType("Not an annotation: " + type);
+        }
+        return type;
     }
 
     public static void checkAnnotationType(

compiler/testData/diagnostics/tests/annotations/typeParameterAsAnnotation.kt

@@ -0,0 +1,9 @@
+class Foo<T> {
+    [<!NOT_A_CLASS!>T<!>]
+    fun foo() = 0
+}
+
+class Bar<T : Annotation> {
+    [<!NOT_A_CLASS!>T<!>]
+    fun foo() = 0
+}

compiler/testData/diagnostics/tests/annotations/typeParameterAsAnnotation.txt

@@ -0,0 +1,17 @@
+package
+
+internal final class Bar</*0*/ T : kotlin.Annotation> {
+    public constructor Bar</*0*/ T : kotlin.Annotation>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    [ERROR : Not an annotation: T]() internal final fun foo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal final class Foo</*0*/ T> {
+    public constructor Foo</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    [ERROR : Not an annotation: T]() internal final fun foo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests/org/jetbrains/kotlin/checkers/JetDiagnosticsTestGenerated.java

@@ -819,6 +819,12 @@ public class JetDiagnosticsTestGenerated extends AbstractJetDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("typeParameterAsAnnotation.kt")
+            public void testTypeParameterAsAnnotation() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/annotations/typeParameterAsAnnotation.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("UnresolvedAnnotationOnObject.kt")
             public void testUnresolvedAnnotationOnObject() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/annotations/UnresolvedAnnotationOnObject.kt");