change class signature: process diamond (IDEA-125236)

java/java-impl/src/com/intellij/refactoring/changeClassSignature/ChangeClassSignatureProcessor.java

@@ -96,6 +96,13 @@ public class ChangeClassSignatureProcessor extends BaseRefactoringProcessor {
         PsiJavaCodeReferenceElement referenceElement = (PsiJavaCodeReferenceElement)reference.getElement();
         PsiElement parent = referenceElement.getParent();
         if (parent instanceof PsiTypeElement && parent.getParent() instanceof PsiInstanceOfExpression) continue;
+        if (parent instanceof PsiNewExpression && PsiUtil.isLanguageLevel7OrHigher(parent)) {
+          final PsiReferenceParameterList parameterList = referenceElement.getParameterList();
+          if (parameterList != null) {
+            final PsiTypeElement[] parameterElements = parameterList.getTypeParameterElements();
+            if (parameterElements.length == 1 && parameterElements[0].getType() instanceof PsiDiamondType) continue;
+          }
+        }
         if (parent instanceof PsiTypeElement || parent instanceof PsiNewExpression || parent instanceof PsiAnonymousClass ||
             parent instanceof PsiReferenceList) {
           if (!hadTypeParameters || referenceElement.getTypeParameters().length > 0) {

java/java-tests/testData/refactoring/changeClassSignature/AddParamDiamond.java

@@ -0,0 +1,5 @@
+class <caret>QueryParameter<T> {}
+
+class UUU {
+  QueryParameter<String> q = new QueryParameter<>();
+}

java/java-tests/testData/refactoring/changeClassSignature/AddParamDiamond.java.after

@@ -0,0 +1,5 @@
+class QueryParameter<T, I> {}
+
+class UUU {
+  QueryParameter<String, Integer> q = new QueryParameter<>();
+}

java/java-tests/testSrc/com/intellij/refactoring/changeClassSignature/ChangeClassSignatureTest.java

@@ -85,6 +85,18 @@ public class ChangeClassSignatureTest extends LightRefactoringTestCase {
     });
   }
 
+  public void testAddParamDiamond() throws Exception {
+    doTest(new GenParams() {
+      @Override
+      public TypeParameterInfo[] gen(PsiClass aClass) throws IncorrectOperationException {
+        return new TypeParameterInfo[] {
+          new TypeParameterInfo(0),
+          new TypeParameterInfo(aClass, "I", "Integer")
+        };
+      }
+    });
+  }
+
   public void testAddOneFirst() throws Exception {
     doTest(new GenParams() {
       @Override