feat: Handle omitzero in structfield linter

[Not-Dhananjay-Mishra]

Added handling for the ,omitzero tag option in processTag (structfield.go) by stripping it from the tag value before further validation, consistent with existing ,omitempty behavior.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.48%. Comparing base (8ca48dd) to head (e6ec5c6).
⚠️ Report is 4 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3881   +/-   ##
=======================================
  Coverage   92.48%   92.48%           
=======================================
  Files         200      200           
  Lines       14564    14564           
=======================================
  Hits        13469    13469           
  Misses        895      895           
  Partials      200      200           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[gmlewis]

Thank you, @Not-Dhananjay-Mishra!
Please add test cases in all the test data that includes new ",omitzero" and ",omitempty,omitzero". I see you added one, but we need examples for all 4 possibilities. (warning, non-warning, single flag, double flags)

[Not-Dhananjay-Mishra]

@gmlewis I added some test cases

No warning -

• SliceOfZerosStructs []*Struct json:"slice_of_zeros_structs,omitzero"
• SliceOfBothOmitTags []*Struct json:"slice_of_both_omit_tags,omitempty,omitzero"

Has warning -

• SliceOfZeroInts []*int json:"slice_of_zero_ints,omitzero"
• SliceOfBothOmitTags []*int json:"slice_of_both_omit_tags,omitempty,omitzero"
• PerPageZeros int url:"per_page_zeros,omitzero"
• PerPageBoth int url:"per_page_both,omitempty,omitzero"

[Not-Dhananjay-Mishra]

Just to confirm, are we going to use omitzero with the following conditions?

• Slice of pointer structs
• Slice of non-pointer data types (int, string)
• Pointer data types

[gmlewis]

OK, now here is where I'm a bit fuzzy - do we want to require using pointers for primitives when using omitzero? Do we want to allow omitzero at all for primitives?

I'm guessing the answer is "it depends on the particular field and its usage", but honestly I don't have experience with omitzero.

Thoughts?

cc: @stevehipwell - @alexandear - @zyfy29

[alexandear]

I propose narrowing the scope and allowing omitzero only for slices, maps, and structs. These are the cases where omitzero reduces a bit of boilerplate.

Maybe in the future we can use omitzero for primitives, but I'm not sure.

[Not-Dhananjay-Mishra]

I propose narrowing the scope and allowing omitzero only for slices, maps, and structs. These are the cases where omitzero reduces a bit of boilerplate.

For these type of data? am i correct?

• []*Struct
• []string/int/...
• Struct (or *Struct)
• map

[gmlewis]

Just to confirm, are we going to use omitzero with the following conditions?

• Slice of pointer structs
• Slice of non-pointer data types (int, string)
• Pointer data types

HAH! We were typing at the same time!

Excellent questions!!! I don't know the answers. I'd like to hear some more opinions.

[Not-Dhananjay-Mishra]

Now omitzero is :

Allowed with -

• []builtin & []*builtin
• map & *map
• Struct & *Struct
• []Struct & []*Struct

Not Allowed with -

• with URL Tag
• builtin & *builtin
• *[]builtin/Struct & *[]*builtin/Struct