Exclude generated code from coverage

[breml]

Fixes #15

[rubensayshi]

hmm, maybe it would be good to make the check a bit more thorough, similar to the isGenerated from the lint tool?
just to be a bit more strict / thorough and not exclude some frankenstein file with a comment floating around somewhere mid-file?

https://pkg.go.dev/cmd/go#hdr-Generate_Go_files_by_processing_source specifies:

This line must appear before the first non-comment, non-blank text in the file.

you can see the test case as well from here which things should be valid: https://github.com/golang/lint/blob/85993ffd0a6cd043291f3f63d45d656d97b165bd/lint_test.go#L292

[breml]

@rubensayshi You are right and I am aware of this specification (I linked it myself in hexdigest/gowrap#20). My issue is, that one of my main use-cases is exactly with gowrap and this tool generates a valid comment, but does not (yet) comply with strict requirement for the position, because the comment is inserted after the package statement.

If you agree, I can change the detection, such that it complies with the test set you linked, which would be sufficient for me.

[breml]

@rubensayshi I added the isGenerated function you linked to in a separate commit.

[rubensayshi]

ehm, I suppose it's fine to adjust isGenerated to also accept package before the comment as an exception?

[breml]

This is already the case in the "original" version of isGenerated, see:

courtney/scanner/generated_test.go

Line 25 in 0e4312f

{"package foo\n// Code generated by some tool. DO NOT EDIT.\ntype foo int\n", true},

I assume, this because this code predates the decision in golang/go#41196

[imsodin]

Should there be a flag/config option for this? There could be projects interested in coverage of generated code.

[dave]

Yeah I think running tests on generated code is common... I do it in some of my projects.

[breml]

@dave No problem, I can add a flag for this. Do you have any preference on the name of the flag? I assume, the default would be to keep the existing behavior for backwards compatibility reasons.

[breml]

@dave Another question, there are several places, where gofmt (respectively goimports and gofumpt) would change the formatting of the code. I did not commit these changes so far. How do you feel about this?