add tagalign linter

[4meepo]

tagalign is used to align and sort tags in golang struct.

eg:

type FooBar struct {
    Foo    int    `json:"foo" validate:"required"`
    Bar    string `json:"bar" validate:"required"`
    FooFoo int8   `json:"foo_foo" validate:"required"`
}

can be aligned to

type FooBar struct {
    Foo    int    `json:"foo"     validate:"required"`
    Bar    string `json:"bar"     validate:"required"`
    FooFoo int8   `json:"foo_foo" validate:"required"`
}

It can also sort tags with user's prefered order.

[boring-cyborg]

Hey, thank you for opening your first Pull Request !

[CLAassistant]

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[ldez]

In order for a pull request adding a linter to be reviewed, the linter and the PR must follow some requirements.

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---

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[4meepo]

hi team, ready for review.

[4meepo]

@alexandear Really thanks for your suggestion. A new test case with auto-sort disabled have been added.

Try:

T=tagalign_no_sort.go make test_linters

[ldez]

The modifications required by the checklist are not done.

@alexandear It's better to wait before reviewing that the user part of the checklist is done.

[4meepo]

If there are anything I need to do, just let me know. : )

[ldez]

Follow the checklist except for boxes with the message "(the team will help to verify that)"

[ldez]

IMO the alignment of the tags is less interesting than the sort of the tags, maybe it can be a good idea to add an option to enable/disable the alignment.
Without this option, I think I will never use this linter.

But this improvement is not a blocker to merging this PR.

[4meepo]

IMO the alignment of the tags is less interesting than the sort of the tags, maybe it can be a good idea to add an option to enable/disable the alignment. Without this option, I think I will never use this linter.

But this improvement is not a blocker to merging this PR.

Nice suggestion. I have added a align configuration option, which is enabled by default. Now the alignment and sort can be used together or separately.

[ldez]

I change a bit the default, the new default: align:true and sort:true
Because I think your linter will be used more if the sort is enabled by default.

Otherwise, I modified the tests to have simpler test cases, and I can see that some options don't work as expected: if align:false the option sort and order don't work.

[4meepo]

Found a bug here.

Should work now.

[ldez]

Thanks for your contribution 👍