Change assignability check for interfaces

test-framework/junit5/src/main/java/io/quarkus/test/junit/MockSupport.java

@@ -36,10 +36,6 @@ static <T> void installMock(T instance, T mock) {
         if (inst == null) {
             throw new IllegalStateException("No test in progress");
         }
-        if (!(instance.getClass().getSuperclass().isAssignableFrom(mock.getClass()))) {
-            throw new RuntimeException(mock
-                    + " is not assignable to type " + instance.getClass().getSuperclass());
-        }
         try {
             Method setMethod = instance.getClass().getDeclaredMethod("arc$setMock", Object.class);
             setMethod.invoke(instance, mock);

test-framework/junit5/src/main/java/io/quarkus/test/junit/QuarkusMock.java

@@ -48,6 +48,12 @@ public static <T> void installMockForInstance(T mock, T instance) {
      */
     public static <T> void installMockForType(T mock, Class<? super T> instance, Annotation... qualifiers) {
         //mock support does the actual work, but exposes other methods that are not part of the user API
+        if (!instance.isAssignableFrom(mock.getClass())) {
+            if (!(instance.getClass().getSuperclass().isAssignableFrom(mock.getClass()))) {
+                throw new RuntimeException(mock
+                        + " is not assignable to type " + instance.getClass().getSuperclass());
+            }
+        }
         MockSupport.installMock(CDI.current().select(instance, qualifiers).get(), mock);
     }
 }