If I open the Progress view and stop a long-running Checkstyle builder, I get an error in the Problems view. This is annoying because it is not really abnormal to stop the job.
Bonus: When I open the Properties view for an error, warning or info problem marker, I don't really get much more info. It would be nice if an execution error could include a stack trace or something. Right now, it just says "Checkstyle execution failed due to an internal error. Please check the error log for details...".
And for a normal check violation, it would be really great if the problem marker could include the name and id of the check that caused the violation. I know there is a setting to tack this onto the message, but I don't like that and would prefer the metadata be located separately in the problem marker's properties.
The module name is actually already added as a marker property. Not sure you can actually make use of that with Eclipse's generic Problems view.
As for the other points:
Open the Progress view, run Checkstyle on any sizeable project, click the Stop button in the Progress view. There should now be an error in the Problems view.
Here is an example of this from the log. As you can see, a simple operation cancelled is the source. I don't think this should be an error in the Problems view since I initiated the cancel.
com.puppycrawl.tools.checkstyle.api.CheckstyleException: Exception was thrown while processing _.java
at com.puppycrawl.tools.checkstyle.Checker.processFiles(Checker.java:294)
at com.puppycrawl.tools.checkstyle.Checker.process(Checker.java:212)
at net.sf.eclipsecs.core.builder.Auditor.runAudit(Auditor.java:157)
at net.sf.eclipsecs.core.jobs.AuditorJob.runInWorkspace(AuditorJob.java:82)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:39)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
Caused by: org.eclipse.core.runtime.OperationCanceledException
at net.sf.eclipsecs.core.builder.Auditor$CheckstyleAuditListener.fileStarted(Auditor.java:291)
at com.puppycrawl.tools.checkstyle.Checker.fireFileStarted(Checker.java:349)
at com.puppycrawl.tools.checkstyle.Checker.processFiles(Checker.java:281)
... 5 more
Fixed for next release (7.3.0)