suggest to delete type arguments when they are not expected (IDEA-79300)

java/java-impl/src/com/intellij/codeInsight/daemon/impl/analysis/GenericsHighlightUtil.java

@@ -157,6 +157,9 @@ public class GenericsHighlightUtil {
           if (pparent instanceof PsiTypeElement) {
             PsiElement variable = pparent.getParent();
             if (variable instanceof PsiVariable) {
+              if (targetParametersNum == 0) {
+                QuickFixAction.registerQuickFixAction(highlightInfo, new RemoveTypeArgumentsFix(variable), null);
+              }
               VariableParameterizedTypeFix.registerIntentions(highlightInfo, (PsiVariable)variable, referenceParameterList);
             }
           }

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/RemoveTypeArgumentsFix.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.codeInsight.daemon.impl.quickfix;
+
+import com.intellij.codeInsight.intention.HighPriorityAction;
+import com.intellij.codeInspection.LocalQuickFixAndIntentionActionOnPsiElement;
+import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.project.Project;
+import com.intellij.psi.*;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * User: anna
+ * Date: 1/18/12
+ */
+public class RemoveTypeArgumentsFix extends LocalQuickFixAndIntentionActionOnPsiElement implements HighPriorityAction {
+  private static final Logger LOGGER = Logger.getInstance("#" + RemoveTypeArgumentsFix.class.getName());
+
+  public RemoveTypeArgumentsFix(@Nullable PsiElement element) {
+    super(element);
+  }
+
+  @NotNull
+  @Override
+  public String getText() {
+    return "Remove type arguments";
+  }
+
+  @NotNull
+  @Override
+  public String getFamilyName() {
+    return getText();
+  }
+
+  @Override
+  public boolean isAvailable(@NotNull Project project,
+                             @NotNull PsiFile file,
+                             @NotNull PsiElement startElement,
+                             @NotNull PsiElement endElement) {
+    return startElement instanceof PsiVariable && startElement.isValid() && ((PsiVariable)startElement).getTypeElement() != null;
+  }
+
+  @Override
+  public void invoke(@NotNull Project project,
+                     @NotNull PsiFile file,
+                     @Nullable("is null when called from inspection") Editor editor,
+                     @NotNull PsiElement startElement,
+                     @NotNull PsiElement endElement) {
+    final PsiVariable psiVariable = (PsiVariable)startElement;
+    final PsiTypeElement typeElement = psiVariable.getTypeElement();
+    LOGGER.assertTrue(typeElement != null);
+    final PsiJavaCodeReferenceElement referenceElement = typeElement.getInnermostComponentReferenceElement();
+    if (referenceElement != null) {
+      final PsiReferenceParameterList parameterList = referenceElement.getParameterList();
+      if (parameterList != null) {
+        parameterList.delete();
+      }
+    }
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/removeTypeArguments/afterRemoveAll.java

@@ -0,0 +1,7 @@
+// "Remove type arguments" "true"
+abstract class SomeClass<K, T> implements Some<K, T> {
+    public abstract void doSomething(K key, Node<caret> root);
+}
+class Node {}
+interface Some<II, OO>{}
+

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/removeTypeArguments/beforeRemoveAll.java

@@ -0,0 +1,7 @@
+// "Remove type arguments" "true"
+abstract class SomeClass<K, T> implements Some<K, T> {
+    public abstract void doSomething(K key, Node<caret><K, T> root);
+}
+class Node {}
+interface Some<II, OO>{}
+

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/removeTypeArguments/beforeRemoveUnavailable.java

@@ -0,0 +1,7 @@
+// "Remove type arguments" "false"
+abstract class SomeClass<K, T> implements Some<K, T> {
+    public abstract void doSomething(K key, Node<caret><K, T> root);
+}
+class Node<G> {}
+interface Some<II, OO>{}
+

java/java-tests/testSrc/com/intellij/codeInsight/daemon/quickFix/RemoveTypeArgumentsTest.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.codeInsight.daemon.quickFix;
+
+public class RemoveTypeArgumentsTest extends LightQuickFixTestCase {
+  public void test() throws Exception { doAllTests(); }
+
+  @Override
+  protected String getBasePath() {
+    return "/codeInsight/daemonCodeAnalyzer/quickFix/removeTypeArguments";
+  }
+}