replace assignment with comparison in condition exps (IDEA-173860)

java/java-impl/src/com/intellij/codeInsight/intention/impl/ReplaceAssignmentWithComparisonFix.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2000-2017 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.intention.impl;
+
+import com.intellij.codeInspection.LocalQuickFixAndIntentionActionOnPsiElement;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.project.Project;
+import com.intellij.psi.*;
+import com.intellij.psi.codeStyle.CodeStyleManager;
+import com.siyeh.InspectionGadgetsBundle;
+import org.jetbrains.annotations.Nls;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class ReplaceAssignmentWithComparisonFix extends LocalQuickFixAndIntentionActionOnPsiElement {
+  public ReplaceAssignmentWithComparisonFix(PsiAssignmentExpression expr) {super(expr);}
+
+  @Override
+  public void invoke(@NotNull Project project,
+                     @NotNull PsiFile file,
+                     @Nullable Editor editor,
+                     @NotNull PsiElement startElement,
+                     @NotNull PsiElement endElement) {
+    PsiBinaryExpression
+      comparisonExpr = (PsiBinaryExpression)JavaPsiFacade.getElementFactory(project).createExpressionFromText("a==b", startElement);
+    PsiAssignmentExpression assignmentExpression = (PsiAssignmentExpression)startElement;
+    comparisonExpr.getLOperand().replace(assignmentExpression.getLExpression());
+    PsiExpression rOperand = comparisonExpr.getROperand();
+    assert rOperand != null;
+    PsiExpression rExpression = assignmentExpression.getRExpression();
+    assert  rExpression != null;
+    rOperand.replace(rExpression);
+    CodeStyleManager.getInstance(project).reformat(assignmentExpression.replace(comparisonExpr));
+  }
+
+  @NotNull
+  @Override
+  public String getText() {
+    return getFamilyName();
+  }
+
+  @Nls
+  @NotNull
+  @Override
+  public String getFamilyName() {
+    return InspectionGadgetsBundle.message("assignment.used.as.condition.replace.quickfix");
+  }
+}

java/java-impl/src/com/intellij/codeInsight/intention/impl/config/QuickFixFactoryImpl.java

@@ -30,6 +30,7 @@ import com.intellij.codeInsight.daemon.quickFix.CreateFieldOrPropertyFix;
 import com.intellij.codeInsight.intention.IntentionAction;
 import com.intellij.codeInsight.intention.IntentionManager;
 import com.intellij.codeInsight.intention.QuickFixFactory;
+import com.intellij.codeInsight.intention.impl.ReplaceAssignmentWithComparisonFix;
 import com.intellij.codeInspection.*;
 import com.intellij.codeInspection.deadCode.UnusedDeclarationInspectionBase;
 import com.intellij.codeInspection.ex.EntryPointsManagerBase;
@@ -124,6 +125,12 @@ public class QuickFixFactoryImpl extends QuickFixFactory {
     return new ImplementMethodsFix(psiElement);
   }
 
+  @NotNull
+  @Override
+  public LocalQuickFixAndIntentionActionOnPsiElement createAssignmentToComparisonFix(PsiAssignmentExpression expr) {
+    return new ReplaceAssignmentWithComparisonFix(expr);
+  }
+
   @NotNull
   @Override
   public LocalQuickFixOnPsiElement createMethodThrowsFix(@NotNull PsiMethod method,