completion for inherited after new: find corresponding type parameter when target type passes to another parameter (IDEA-157803)

java/java-impl/src/com/intellij/codeInsight/CodeInsightUtil.java

@@ -366,6 +366,12 @@ public class CodeInsightUtil {
       for (PsiTypeParameter inheritorParameter : PsiUtil.typeParametersIterable(inheritor)) {
         for (PsiTypeParameter baseParameter : PsiUtil.typeParametersIterable(baseClass)) {
           final PsiType substituted = superSubstitutor.substitute(baseParameter);
+          PsiClass inheritorCandidateParameter = PsiUtil.resolveClassInType(substituted);
+          if (inheritorCandidateParameter instanceof PsiTypeParameter &&
+              ((PsiTypeParameter)inheritorCandidateParameter).getOwner() == inheritor &&
+               inheritorCandidateParameter != inheritorParameter) {
+            continue;
+          }
           PsiType arg = baseSubstitutor.substitute(baseParameter);
           if (arg instanceof PsiWildcardType) {
             PsiType bound = ((PsiWildcardType)arg).getBound();
@@ -376,7 +382,7 @@ public class CodeInsightUtil {
                                                                                arg,
                                                                                true,
                                                                                PsiUtil.getLanguageLevel(context));
-          if (PsiType.NULL.equals(substitution) || substitution != null && substitution.equalsToText(CommonClassNames.JAVA_LANG_OBJECT) || substitution instanceof PsiWildcardType) continue;
+          if (PsiType.NULL.equals(substitution) || substitution instanceof PsiWildcardType) continue;
           if (substitution == null) {
             result.consume(createType(inheritor, facade.getElementFactory().createRawSubstitutor(inheritor), arrayDim));
             return true;

java/java-tests/testData/codeInsight/completion/smartType/InferredObjects.java

@@ -0,0 +1,7 @@
+class M<K, V> {}
+class HM<K, V> extends M<K, V> {}
+class Foo {
+  {
+    M<String, Object> m = new <caret>
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/SmartType18CompletionTest.java

@@ -233,6 +233,11 @@ public void testConvertToObjectStream() {
     assertOrderedEquals(myFixture.getLookupElementStrings(), "get2");
   }
 
+  public void testInferredObjects() {
+    configureByTestName();
+    assertOrderedEquals(myFixture.getLookupElementStrings(), "M", "HM");
+  }
+
   public void testSuggestMapInheritors() { doTest(); }
 
   public void testUnboundTypeArgs() { doTest(); }