cast conversion applicable for wildcard vs type parameter if bounds agree (IDEA-75628)

java/java-psi-api/src/com/intellij/psi/util/TypesDistinctProver.java

@@ -262,7 +262,13 @@ public class TypesDistinctProver {
       final PsiType boundBound = ((PsiWildcardType)bound).getBound();
       if (boundBound != null && !boundBound.equals(type)) {
         final PsiClass psiClass = PsiUtil.resolveClassInClassTypeOnly(boundBound);
-        return psiClass == null || !(((PsiWildcardType)bound).isExtends() && possibleClasses.contains(psiClass));
+        if (psiClass == null) {
+          return true;
+        }
+        if (psiClass instanceof PsiTypeParameter) {
+          return try2ProveTypeParameterDistinct(type, psiClass);
+        }
+        return !(((PsiWildcardType)bound).isExtends() && possibleClasses.contains(psiClass));
       }
       return false;
     }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting/TypeDistinctProverForWildcardAndTypeParameter.java

@@ -0,0 +1,18 @@
+abstract class Test {
+  interface Selection<A> {}
+  interface CriteriaQuery<T> {
+    void select(Selection<? extends T> selection);
+  }
+
+  private <N> void foo(CriteriaQuery<N> criteria, Selection<String[]> array) {
+    criteria.select((Selection<? extends N>)array);
+  }
+
+  private <N extends Integer> void foo1(CriteriaQuery<N> criteria, Selection<String[]> array) {
+    criteria.select(<error descr="Inconvertible types; cannot cast 'Test.Selection<java.lang.String[]>' to 'Test.Selection<? extends N>'">(Selection<? extends N>)array</error>);
+  }
+
+  private <N extends Integer> void foo2(CriteriaQuery<N> criteria, Selection<Object> array) {
+    criteria.select(<error descr="Inconvertible types; cannot cast 'Test.Selection<java.lang.Object>' to 'Test.Selection<? extends N>'">(Selection<? extends N>)array</error>);
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/GenericsHighlightingTest.java

@@ -459,6 +459,10 @@ public class GenericsHighlightingTest extends LightDaemonAnalyzerTestCase {
     doTest(LanguageLevel.JDK_1_7, JavaSdkVersion.JDK_1_7, false);
   }
 
+  public void testTypeDistinctProverForWildcardAndTypeParameter() throws Exception {
+    doTest(LanguageLevel.JDK_1_7, JavaSdkVersion.JDK_1_7, false);
+  }
+
   public void testJavaUtilCollections_NoVerify() throws Exception {
     PsiClass collectionsClass = getJavaFacade().findClass("java.util.Collections", GlobalSearchScope.moduleWithLibrariesScope(getModule()));
     assertNotNull(collectionsClass);