SimplifyBooleanExpressionCheck.java

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////////////////////////////////////////////////////////////////////////////////
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// checkstyle: Checks Java source code for adherence to a set of rules.
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// Copyright (C) 2001-2018 the original author or authors.
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2.1 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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// Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License along with this library; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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////////////////////////////////////////////////////////////////////////////////
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package com.puppycrawl.tools.checkstyle.checks.coding;
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import com.puppycrawl.tools.checkstyle.StatelessCheck;
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import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
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import com.puppycrawl.tools.checkstyle.api.DetailAST;
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import com.puppycrawl.tools.checkstyle.api.TokenTypes;
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/**
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 * <p>
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 * Checks for overly complicated boolean expressions. Currently finds code like
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 * {@code if (b == true)}, {@code b || true}, {@code !false},
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 * etc.
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 * </p>
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 * <p>
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 * Rationale: Complex boolean logic makes code hard to understand and maintain.
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 * </p>
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 * <p>
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 * An example of how to configure the check is:
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 * </p>
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 * <pre>
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 * &lt;module name="SimplifyBooleanExpression"/&gt;
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 * </pre>
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 * @author lkuehne
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 */
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@StatelessCheck
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public class SimplifyBooleanExpressionCheck
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        extends AbstractCheck {
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    /**
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     * A key is pointing to the warning message text in "messages.properties"
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     * file.
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     */
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    public static final String MSG_KEY = "simplify.expression";
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    @Override
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    public int[] getDefaultTokens() {
56 1 1. getDefaultTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getDefaultTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
 
        return getRequiredTokens();
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    }
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    @Override
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    public int[] getAcceptableTokens() {
61 1 1. getAcceptableTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getAcceptableTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
 
        return getRequiredTokens();
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    }
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    @Override
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    public int[] getRequiredTokens() {
66 1 1. getRequiredTokens : mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getRequiredTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
 
        return new int[] {TokenTypes.LITERAL_TRUE, TokenTypes.LITERAL_FALSE};
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    }
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    @Override
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    public void visitToken(DetailAST ast) {
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        final DetailAST parent = ast.getParent();
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        switch (parent.getType()) {
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            case TokenTypes.NOT_EQUAL:
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            case TokenTypes.EQUAL:
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            case TokenTypes.LNOT:
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            case TokenTypes.LOR:
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            case TokenTypes.LAND:
78 1 1. visitToken : removed call to com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::log → KILLED
 
                log(parent.getLineNo(), parent.getColumnNo(),
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                    MSG_KEY);
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                break;
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            default:
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                break;
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        }
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    }
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}

Mutations

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1.1
Location : getDefaultTokens
Killed by : com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest.testTokensNotNull(com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest) mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getDefaultTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
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1.1
Location : getAcceptableTokens
Killed by : com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest.testTokensNotNull(com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest) mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getAcceptableTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
66

1.1
Location : getRequiredTokens
Killed by : com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest.testTokensNotNull(com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest) mutated return of Object value for com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::getRequiredTokens to ( if (x != null) null else throw new RuntimeException ) → KILLED
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1.1
Location : visitToken
Killed by : com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest.testIt(com.puppycrawl.tools.checkstyle.checks.coding.SimplifyBooleanExpressionCheckTest) removed call to com/puppycrawl/tools/checkstyle/checks/coding/SimplifyBooleanExpressionCheck::log → KILLED

Active mutators

Tests examined


Report generated by PIT 1.3.1