fix #751 [rule.add-constant] add ignoreFuncs to exclude constants in …

[rawen17]

Closes #751

[chavacava]

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In general I think regexps are too powerful (or complicated?) to be used without the risk of ignoring things you don't know you are ignoring. For example, the regexp .Println used in the tests will not ignore just "methods named Println of any package" but also any method or function named such as Println is a suffix of the name (myPrintln, ThisIsAnotherPrintln, dPrintlln, ...)

[xobotyi]

The problem is out of thin air🙃

We face the regexp if not every day, but commonly and there is nothing "overcomplicated" with it, it is just a right tool for such situation, most of existing linters included in golangcilint uses regexp.

Example you've given easily solvable by reading the docs and acknowledging that it is a regexp and then heading to regexp101. And easily avoidable by gicing some defauls and\or examples in docs.

Anyways having regexes is much better and easier option that needing to exclude separately all 36 argument methods having defaults from flag package, and same for pflag.

[chavacava]

My point is that RE are very error prone (at the point that your own test case .Println was wrong)
I'm not against the use of RE and I agree that providing clear doc will help in avoiding subtle errors; for example in the rule documentation it should be interesting to highlight that fmt.Println in the given example, will make revive ignore fmt.Println, fmtXPrintln, fmt1Println, an so on.

[rawen17]

It was my fault, i had to write regexp os\\.*,fmt\\.Println,make in documentation, but i wrote os.*,fmt.Println,make
I will fix it

[chavacava]

It was my fault, i had to write regexp os\\.*,fmt\\.Println,make in documentation, but i wrote os.*,fmt.Println,make I will fix it

@rawen17 thanks for the PR, I've already merged it.
Sorry @xobotyi I did not notice that I was answering to you (and not to the author of the PR)

[rawen17]

@chavacava Ok, thanks, i will create new PR for this changes