[ament_copyright, ament_uncrustify] Unexpected file exclusion behavior

[aprotyas]

Problem description

The --exclude flag for ament_copyright/ament_uncrustify does not work as expected, or at least not how file exclusion works in some other packages like ament_cpplint and ament_cppcheck.

The issues I've noted:

• File paths (both relative and absolute) don't work for the arguments to the --exclude flag. Only the excluded filename(s) can be provided.
• As a consequence of the above issue, provided filenames are excluded indiscriminately throughout its search tree.

In any case, this behavior is not consistent with how exclusion works (and/or should work in my opinion) for some other linter packages.

Problem demonstration

For the following examples, let the following search tree. The expected behavior is in bold. Output is shown for ament_copyright but the same idea applies for ament_uncrustify.

.
├── dir
│  └── src.cpp
└── src.cpp

Example 1: File paths don't work

ament_copyright . --exclude dir/src.cpp should only exclude dir/src.cpp. Instead, neither of the files are excluded and it outputs:

No problems found, checked 2 files

Example 2: Indiscriminate matching to a filename

ament_copyright . --exclude src.cpp should only exclude src.cpp. Instead, both of the files are excluded and it outputs:

No repository roots and files found
No problems found, checked 0 files

Comments

I reckon this exclusion behavior can be remedied if a solution like #299 is used. On that note, I've opened #327. If maintainers think those changes are good, I will give a similar treatment to ament_uncrustify in a separate PR.

Another thought is that the "correct" code to filter out excluded files can be put in a separate utility module that all the linting packages can access, because it looks like every ament_[linter] is doing it slightly differently...

[aprotyas]

Since #327 and #334 have merged, this issue is resolved.