Issue #7765: XpathRegression tests added for UnnecessaryParentheses

src/it/java/org/checkstyle/suppressionxpathfilter/XpathRegressionUnnecessaryParenthesesTest.java

@@ -0,0 +1,243 @@
+////////////////////////////////////////////////////////////////////////////////
+// checkstyle: Checks Java source code for adherence to a set of rules.
+// Copyright (C) 2001-2020 the original author or authors.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+////////////////////////////////////////////////////////////////////////////////
+
+package org.checkstyle.suppressionxpathfilter;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import com.puppycrawl.tools.checkstyle.DefaultConfiguration;
+import com.puppycrawl.tools.checkstyle.checks.coding.UnnecessaryParenthesesCheck;
+
+public class XpathRegressionUnnecessaryParenthesesTest extends AbstractXpathTestSupport {
+
+    @Override
+    protected String getCheckName() {
+        return UnnecessaryParenthesesCheck.class.getSimpleName();
+    }
+
+    @Test
+    public void testOne() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses1.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "4:13: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_ASSIGN),
+        };
+
+        final List<String> expectedXpathQueries = Arrays.asList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses1']]"
+                + "/OBJBLOCK/VARIABLE_DEF[./IDENT[@text='a']]"
+                + "/ASSIGN/EXPR",
+
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses1']]"
+                + "/OBJBLOCK/VARIABLE_DEF[./IDENT[@text='a']]"
+                + "/ASSIGN/EXPR/LPAREN"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testTwo() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses2.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:13: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_EXPR),
+        };
+
+        final List<String> expectedXpathQueries = Arrays.asList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses2']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/LITERAL_IF/EXPR",
+
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses2']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/LITERAL_IF/EXPR/LPAREN"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testThree() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses3.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "7:35: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_LAMBDA),
+        };
+
+        final List<String> expectedXpathQueries = Collections.singletonList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses3']]"
+                + "/OBJBLOCK/VARIABLE_DEF[./IDENT[@text='predicate']]"
+                + "/ASSIGN/LAMBDA"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testFour() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses4.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:18: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_IDENT, "a"),
+        };
+
+        final List<String> expectedXpathQueries = Collections.singletonList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses4']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/VARIABLE_DEF[./IDENT[@text='b']]"
+                + "/ASSIGN/EXPR/PLUS/IDENT[@text='a']"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testFive() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses5.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:23: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_STRING, "\"Checkstyle\""),
+        };
+
+        final List<String> expectedXpathQueries = Collections.singletonList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses5']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/VARIABLE_DEF[./IDENT[@text='str']]"
+                + "/ASSIGN/EXPR/PLUS/STRING_LITERAL[@text='Checkstyle']"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testSix() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses6.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:18: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_LITERAL, "10"),
+        };
+
+        final List<String> expectedXpathQueries = Collections.singletonList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses6']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/VARIABLE_DEF[./IDENT[@text='a']]"
+                + "/ASSIGN/EXPR/PLUS/NUM_INT[@text='10']"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testSeven() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses7.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:16: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_RETURN),
+        };
+
+        final List<String> expectedXpathQueries = Arrays.asList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses7']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/LITERAL_RETURN/EXPR",
+
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses7']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/LITERAL_RETURN/EXPR/LPAREN"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+
+    @Test
+    public void testEight() throws Exception {
+        final File fileToProcess = new File(
+            getPath("SuppressionXpathRegressionUnnecessaryParentheses8.java")
+        );
+
+        final DefaultConfiguration moduleConfig =
+            createModuleConfig(UnnecessaryParenthesesCheck.class);
+
+        final String[] expectedViolation = {
+            "5:17: " + getCheckMessage(UnnecessaryParenthesesCheck.class,
+                UnnecessaryParenthesesCheck.MSG_ASSIGN),
+        };
+
+        final List<String> expectedXpathQueries = Arrays.asList(
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses8']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/VARIABLE_DEF[./IDENT[@text='c']]"
+                + "/ASSIGN/EXPR",
+
+            "/CLASS_DEF[./IDENT[@text='SuppressionXpathRegressionUnnecessaryParentheses8']]"
+                + "/OBJBLOCK/METHOD_DEF[./IDENT[@text='foo']]"
+                + "/SLIST/VARIABLE_DEF[./IDENT[@text='c']]"
+                + "/ASSIGN/EXPR/LPAREN"
+        );
+
+        runVerifications(moduleConfig, fileToProcess, expectedViolation, expectedXpathQueries);
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses1.java

@@ -0,0 +1,5 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses1 {
+    int a = (2*2); // warn
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses2.java

@@ -0,0 +1,8 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses2 {
+    void foo(String a) {
+        if (('A' == a.charAt(0))) { // warn
+        }
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses3.java

@@ -0,0 +1,8 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses3 {
+    public interface Predicate {
+        boolean test(Integer t);
+    }
+    Predicate predicate = (value) -> value != null; // warn
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses4.java

@@ -0,0 +1,7 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses4 {
+    void foo (int a) {
+        int b = (a) + 5; // warn
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses5.java

@@ -0,0 +1,7 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses5 {
+    void foo () {
+        String str = ("Checkstyle") + "is cool"; // warn
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses6.java

@@ -0,0 +1,7 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses6 {
+    void foo () {
+        int a = (10) + 5; // warn
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses7.java

@@ -0,0 +1,7 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses7 {
+    int foo (int a) {
+        return (a+6); // warn
+    }
+}

src/it/resources/org/checkstyle/suppressionxpathfilter/unnecessaryparentheses/SuppressionXpathRegressionUnnecessaryParentheses8.java

@@ -0,0 +1,7 @@
+package org.checkstyle.suppressionxpathfilter.unnecessaryparentheses;
+
+public class SuppressionXpathRegressionUnnecessaryParentheses8 {
+    void foo(int a, int b) {
+        int c = (a*b); // warn
+    }
+}

src/main/java/com/puppycrawl/tools/checkstyle/filters/SuppressionXpathFilter.java

@@ -73,9 +73,6 @@
  * TrailingComment
  * </li>
  * <li>
- * UnnecessaryParentheses
- * </li>
- * <li>
  * VariableDeclarationUsageDistance
  * </li>
  * </ul>

src/test/java/com/puppycrawl/tools/checkstyle/internal/XpathRegressionTest.java

@@ -64,7 +64,6 @@ public class XpathRegressionTest extends AbstractModuleTestSupport {
             "RegexpSinglelineJava (reason is at  #7759)",
             "TodoComment",
             "TrailingComment",
-            "UnnecessaryParentheses",
             "VariableDeclarationUsageDistance"
     )));
 

src/xdocs/config_filters.xml

@@ -928,7 +928,6 @@ public class UserService {
           <li>RegexpSinglelineJava (reason is at <a href="https://github.com/checkstyle/checkstyle/issues/7759#issuecomment-605525287"> #7759</a>)</li>
           <li>TodoComment</li>
           <li>TrailingComment</li>
-          <li>UnnecessaryParentheses</li>
           <li>VariableDeclarationUsageDistance</li>
         </ul>
         <p>