Update google_checks.xml to have the SuppressionCommentFilter and SuppressWarningsHolder modules in the config by default (and by extension, SuppressWarningsFilter)

[ddcprg]

I have downloaded the latest cli from: https://checkstyle.org/cmdline.html#Download_and_Run
I have executed the cli and showed it below, as cli describes the problem better than 1,000 words

How it works Now:

/var/tmp $ javac MyClass.java
#[[MAKE SURE THERE IS SUCCESSFUL COMPILATION]]

/var/tmp $ cat google_checks.xml
...
<module name="Checker">
  <!-- IMPORTANT: Allows use of SuppressWarnings annotation -->
  <module name="SuppressWarningsFilter"/>
  ...
  <module name="TreeWalker">
    <module name="SuppressWarningsHolder" />
    <module name="SuppressionCommentFilter">
      <property name="offCommentFormat" value="CHECKSTYLE.OFF\: ([\w\|]+)" />
      <property name="onCommentFormat" value="CHECKSTYLE.ON\: ([\w\|]+)" />
      <property name="checkFormat" value="$1" />
    </module>
...
</module>


/var/tmp $ cat MyClass.java
class MyClass {
  public void aMethod() {
  }
}


/var/tmp $ RUN_LOCALE="-Duser.language=en -Duser.country=US"
/var/tmp $ java $RUN_LOCALE -jar checkstyle-10.2-all.jar -c google_checks.xml MyClass.java
Starting audit...
[WARN] /var/tmp/MyClass.java:2:15: Method name 'aMethod' must match pattern '^[a-z][a-z0-9][a-zA-Z0-9_]*$'. [MethodName]
Audit done.

After using @SuppressWarnings

/var/tmp $ cat MyClass.java
class MyClass {
  @SuppressWarnings("checkstyle:methodname")
  public void aMethod() {
  }
}


/var/tmp $ RUN_LOCALE="-Duser.language=en -Duser.country=US"
/var/tmp $ java $RUN_LOCALE -jar checkstyle-10.2-all.jar -c google_checks.xml MyClass.java
Starting audit...
Audit done.

Using special comments to switch checkstyle off and on:

/var/tmp $ cat MyClass.java
class MyClass {
  // CHECKSTYLE.OFF: MethodName
  public void aMethod() {
  }
  // CHECKSTYLE.ON: MethodName
}


/var/tmp $ RUN_LOCALE="-Duser.language=en -Duser.country=US"
/var/tmp $ java $RUN_LOCALE -jar checkstyle-10.2-all.jar -c google_checks.xml MyClass.java
Starting audit...
Audit done.

Is your feature request related to a problem? Please describe.
No, this is just additional config in google_checks.xml.

Describe the solution you'd like
Add the ability to suppress style checks via annotations and special comments around the code. This will offer users alternatives to suppress checks other than using XML.

Additional context
Some of these changes have been already adopted by Google https://github.com/GoogleCloudPlatform/java-repo-tools/blob/main/third_party/checkstyle/google_checks.xml

References

• http://stackoverflow.com/a/22556386/101923
• http://stackoverflow.com/questions/4023185

[nrmancuso]

@ddcprg please remove all modules from your config that are not related to this issue to make your example easier to read and understand.

[ddcprg]

@nick-mancuso I've updated the config to show the relevant bits only

[nrmancuso]

@ddcprg to be clear, you would like google_checks.xml to have the SuppressionCommentFilter and SuppressWarningsHolder modules in the config by default (and by extension, SuppressWarningsFilter), correct?

[ddcprg]

that's correct @nick-mancuso I've raised PR even though the ticket hasn't been approved #11656

[nrmancuso]

This request makes sense to me, since we currently do not support anything that makes inheritance/ override in configs possible, such as #2873. @romani what do you think?

[nrmancuso]

@ddcprg please update issue title to be more along the lines of #11655 (comment), make sure to mention modules you want and google_checks.xml, please.

[ddcprg]

@nick-mancuso thanks, copy&pasted now - almost

[romani]

Users should be able to suppress violations in way they want.
We might need need to add something like

checkstyle/config/checkstyle_checks.xml

Line 577 in 74747a2

<module name="SuppressWithNearbyCommentFilter">

also to let users use comments also

[nrmancuso]

Approved, in PR for this issue, we should do:

1. Add SuppressWithNearbyCommentFilter, SuppressionCommentFilter, and SuppressWarningsHolder modules to google_checks.xml
2. Add SuppressWarningsFilter module to google_checks.xml
3. Update documentation at https://checkstyle.sourceforge.io/google_style.html#Google_Suppressions

[ddcprg]

thanks @nick-mancuso @romani I'll include the additional module and fix the PR

[nrmancuso]

Fix was merged.