Create Treewalker filter SuppressionPatchXpathFilter that suppress all violations on non affected lines

[checkstyle]

Create Treewalker filter SuppressionPatchXpathFilter that suppress all violations on non affected lines

[HuGanghui]

I do a test to familiar with SuppressionPatchXpathFilter/SuppressionXpathSingleFilter

cat Test.java

package checkstyle_demo.PatchSuppression.PatchFilterTest.XpathPatchFilter;


class FileOne {
    public void MyMethod() {}
}

class FileTwo {
    public void MyMethod() {}
}

class FileThree {
    public void MyMethod() {}
}

cat config.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
        "https://checkstyle.org/dtds/configuration_1_3.dtd">
<module name="Checker">

    <!--<module name="com.github.checkstyle.patchfilter.SuppressionPatchFilter">-->
        <!--<property name="file" value="/Users/hgh/Downloads/my_file/IDEA_workspace/Leetcode_maven/engineering_ability/src/main/java/checkstyle_demo/PatchSuppression/MethodCount/patch.txt"/>-->
    <!--</module>-->
    <!--<module name="com.puppycrawl.tools.checkstyle.filters.SuppressionPatchFilter">-->
        <!--<property name="file" value="/Users/hgh/Downloads/my_file/IDEA_workspace/Leetcode_maven/engineering_ability/src/main/java/checkstyle_demo/PatchSuppression/PatchFilterTest/guava-patch-c34f584-31999ae.txt"/>-->
    <!--</module>-->

    <module name="TreeWalker">

        <module name="MethodName"/>

        <module name="SuppressionXpathSingleFilter">
            <property name="checks" value="MethodName"/>
            <property name="query" value="(/CLASS_DEF[@text='FileOne']/OBJBLOCK/
            METHOD_DEF[@text='MyMethod']/IDENT)|
            (/CLASS_DEF[@text='FileTwo']/OBJBLOCK/METHOD_DEF[@text='MyMethod']/IDENT)"/>
        </module>

    </module>

    <!-- as we run on regression even on non-compiled files we need to skip exceptions on them -->
    <module name="SuppressionSingleFilter">
        <property name="message" value="Exception occurred while parsing"/>
        <property name="checks" value="Checker"/>
    </module>

</module>

java $RUN_LOCALE -jar /Users/hgh/Desktop/checkstyle/target/checkstyle-8.34-SNAPSHOT-all.jar -c config.xml Test.java

Starting audit...
[ERROR] /Users/hgh/Downloads/my_file/IDEA_workspace/Leetcode_maven/engineering_ability/src/main/java/checkstyle_demo/PatchSuppression/PatchFilterTest/XpathPatchFilter/Test.java:5:17: Name 'MyMethod' must match pattern '^[a-z][a-zA-Z0-9]*$'. [MethodName]
[ERROR] /Users/hgh/Downloads/my_file/IDEA_workspace/Leetcode_maven/engineering_ability/src/main/java/checkstyle_demo/PatchSuppression/PatchFilterTest/XpathPatchFilter/Test.java:9:17: Name 'MyMethod' must match pattern '^[a-z][a-zA-Z0-9]*$'. [MethodName]
[ERROR] /Users/hgh/Downloads/my_file/IDEA_workspace/Leetcode_maven/engineering_ability/src/main/java/checkstyle_demo/PatchSuppression/PatchFilterTest/XpathPatchFilter/Test.java:13:17: Name 'MyMethod' must match pattern '^[a-z][a-zA-Z0-9]*$'. [MethodName]
Checkstyle ends with 3 errors.
Audit done.

but it should be one violation right? Why the SuppressionXpathSingleFilter does not have effect, please tell me if I am incorrect in some steps.

[rdiachenko]

@HuGanghui please read - https://checkstyle.sourceforge.io/cmdline.html and try to fix yourself.

Tip: some options might be useful.

[HuGanghui]

While mentors are busy to analyze report and make decision on what to do. Student should implement the same filter(line >only) but for Treewalker and generate report on guava for google-checks.xml config. - https://github.com/checkstyle/patch->filters/issues/6

according to doc, the same filter(line only), do we need to use current patch filter (line) to test checks belong to Treewalker?

[romani]

@HuGanghui , we should not use already implemented SuppressionPatchFilter at all.
You create completely new Filter, some functionality might overlap but it is ok.
New filter should be located under TreeWalker in config and should be similar to https://github.com/checkstyle/checkstyle/blob/master/src/main/java/com/puppycrawl/tools/checkstyle/filters/SuppressionXpathFilter.java#L501 plus ability to consider patch details.

[HuGanghui]

@romani OK, I got it.

[baratali]

Implemeneted in #90