Enforce FileTabCharacter and RegexpSingleline for trailing whitespace over resources

[romani]

uncomment configuration at: https://github.com/checkstyle/checkstyle/blob/master/config/checkstyle_resources_checks.xml#L18-L24

fix all violations.
It is better to split violation resolving in few PRs for each Check.
UT might be required to be updated - but ideally should not be updated.

[rnveach]

RegexpSingleline has 1000 violations.
FileTab has 145 violations.

[rnveach]

@romani When are tabs/spaces part of the tests outside of indentation/filetab ?
AST/Javadoc printing is picking them up in their results. Is it ok to change them and cause differences in tests?

A lot of inputs say they have tabs on purpose. naming, sizes, todo, whitespace, plain text suppression. It makes it a little tougher to identify them and will require more suppressions.

[romani]

When are tabs/spaces part of the tests outside of indentation/filetab ?

Naming should not have tabs .

A lot of inputs say they have tabs on purpose

It might be copy paste.

whitespace, plain text suppression.

Such grops can have tabs, but it is better to limit such inputs to certain list.

will require more suppressions.

Yes, I am completely ok with this. Ideally input files will have "withTabs" in names, so suppression will be easy. But as first step, list of inputs with certain names is good.

[rnveach]

Javadooc grammar may need an extra fix for new lines. I am seeing this on Windows:

|           |--ATTRIBUTE -> ATTRIBUTE [38:10]
|           |   |--HTML_TAG_NAME -> attr [38:10]
|           |   |--EQUALS -> = [38:14]
|           |   `--ATTR_VALUE -> "something" [38:15]
|           |--WS ->   [38:27]
|           |--NEWLINE -> \n [38:28]

gets converted to:

|           |--ATTRIBUTE -> ATTRIBUTE [38:10]
|           |   |--HTML_TAG_NAME -> attr [38:10]
|           |   |--EQUALS -> = [38:14]
|           |   `--ATTR_VALUE -> "something"\r [38:15]
|           |--NEWLINE -> \n [38:27]

which has the random \r on the end of the attribute value.

[romani]

Check still need to be enforced in config, but most of code changes is done

[Boukhalfa11]

I am a student and I am a new to this projects, can i take this issue, and how can I help with this issue please ?

[romani]

@Boukhalfa11 , read https://github.com/checkstyle/checkstyle/wiki/To-GSoC-participant