ReplaceEqualsWithEqualityIntention.java

/*
 * Copyright 2003-2013 Dave Griffith, Bas Leijdekkers
 *
 * 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.siyeh.ipp.equality;

import com.intellij.psi.*;
import com.intellij.util.IncorrectOperationException;
import com.siyeh.ig.PsiReplacementUtil;
import com.siyeh.ig.psiutils.ParenthesesUtils;
import com.siyeh.ipp.base.Intention;
import com.siyeh.ipp.base.PsiElementPredicate;
import org.jetbrains.annotations.NotNull;

public class ReplaceEqualsWithEqualityIntention extends Intention {

  @NotNull
  public PsiElementPredicate getElementPredicate() {
    return new EqualsPredicate();
  }

  public void processIntention(PsiElement element)
    throws IncorrectOperationException {
    final PsiMethodCallExpression call =
      (PsiMethodCallExpression)element;
    if (call == null) {
      return;
    }
    final PsiReferenceExpression methodExpression =
      call.getMethodExpression();
    final PsiExpression target = methodExpression.getQualifierExpression();
    if (target == null) {
      return;
    }
    final PsiExpressionList argumentList = call.getArgumentList();
    final PsiExpression arg = argumentList.getExpressions()[0];
    final PsiExpression strippedTarget =
      ParenthesesUtils.stripParentheses(target);
    if (strippedTarget == null) {
      return;
    }
    final PsiExpression strippedArg =
      ParenthesesUtils.stripParentheses(arg);
    if (strippedArg == null) {
      return;
    }
    final String strippedArgText;
    if (ParenthesesUtils.getPrecedence(strippedArg) >
        ParenthesesUtils.EQUALITY_PRECEDENCE) {
      strippedArgText = '(' + strippedArg.getText() + ')';
    }
    else {
      strippedArgText = strippedArg.getText();
    }
    final String strippedTargetText;
    if (ParenthesesUtils.getPrecedence(strippedTarget) >
        ParenthesesUtils.EQUALITY_PRECEDENCE) {
      strippedTargetText = '(' + strippedTarget.getText() + ')';
    }
    else {
      strippedTargetText = strippedTarget.getText();
    }
    PsiReplacementUtil.replaceExpression(call, strippedTargetText + "==" + strippedArgText);
  }
}