type arguments agree when one is type parameter and another is not any wildcard (IDEA-67427)

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

@@ -0,0 +1,33 @@
+import java.lang.Double;
+
+interface IConverter<C> {
+}
+
+abstract class AbstractNumberConverter<N extends Number> implements IConverter<N> {
+}
+
+class DoubleConverter extends AbstractNumberConverter<Double> {
+}
+
+public class Test {
+  public static <C> IConverter<C> getConverter(Class<C> type) {
+    return (IConverter<C>)new DoubleConverter() {
+    };
+  }
+
+  public static <C extends String> IConverter<C> getConverter1(Class<C> type) {
+    return <error descr="Inconvertible types; cannot cast 'DoubleConverter' to 'IConverter<C>'">(IConverter<C>)new DoubleConverter() {
+    }</error>;
+  }
+
+  public static <C extends Double> IConverter<C> getConverter2(Class<C> type) {
+    return (IConverter<C>)new DoubleConverter() {
+    };
+  }
+
+  public static void main(String[] args) {
+    IConverter<String> converter = getConverter(String.class);
+    IConverter<String> converter1 = getConverter1(String.class);
+    IConverter<String> converter2 = <error descr="Inferred type 'java.lang.String' for type parameter 'C' is not within its bound; should extend 'java.lang.Double'">getConverter2(String.class)</error>;
+  }
+}

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

@@ -96,6 +96,7 @@ public class GenericsHighlightingTest extends LightDaemonAnalyzerTestCase {
   public void testMethodSignatureEquality() throws Exception { doTest(false); }
   public void testInnerClassRef() throws Exception { doTest(false); }
   public void testPrivateInnerClassRef() throws Exception { doTest(false); }
+  public void testWideningCastToTypeParam() throws Exception { doTest(false); }
 
   public void testJavaUtilCollections_NoVerify() throws Exception {
     PsiClass collectionsClass = getJavaFacade().findClass("java.util.Collections", GlobalSearchScope.moduleWithLibrariesScope(getModule()));

java/openapi/src/com/intellij/psi/util/TypeConversionUtil.java

@@ -19,6 +19,7 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.roots.ProjectRootManager;
 import com.intellij.openapi.util.Key;
+import com.intellij.openapi.vcs.changes.IgnoredFileBean;
 import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.*;
 import com.intellij.psi.search.GlobalSearchScope;
@@ -862,6 +863,14 @@ public class TypeConversionUtil {
       }
     }
     else {
+      final PsiClass leftClass = PsiUtil.resolveClassInType(typeLeft);
+      if (leftClass instanceof PsiTypeParameter) {
+        for (PsiClassType leftClassType : leftClass.getExtendsListTypes()) {
+          if (TypesDistinctProver.provablyDistinct(leftClassType, typeRight)) return false;
+        }
+        if (!(typeRight instanceof PsiCapturedWildcardType || typeRight instanceof PsiWildcardType)) return true;
+      }
+
       return typeLeft.equals(typeRight);
     }
   }