Add check for npos, when checkInternal receives file with missing dot

[GNL10]

No description provided.

[GNL10]

Currently after the UTs finish there is a file that does not get deleted (e.g. outputfile_18314070737314589129.plist).
This is caused by the UT added in this PR. When reportErr is called inside in the negative scenario.

Not entirely sure what the most appropriate way to delete that file should be.

[danmar]

I like this PR. But CI fails right now.

[danmar]

strange it seems to complain about the test you added:
https://github.com/danmar/cppcheck/actions/runs/18859083744/job/53813515383?pr=7911#step:11:132

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[GNL10]

strange it seems to complain about the test you added: https://github.com/danmar/cppcheck/actions/runs/18859083744/job/53813515383?pr=7911#step:11:132

Test was failing due to the hash function giving different output depending on the platform type.
Should be good now!

[danmar]

I merged this PR.. I would like to add your name in the AUTHORS file.. should I write Goncalo Mao-Cheia?

[GNL10]

I merged this PR.. I would like to add your name in the AUTHORS file.. should I write Goncalo Mao-Cheia?

Yes "Goncalo Mao-Cheia" is fine. Thanks!