feat(linter): add line-length rule

[felipeasimos]

The idea of this PR is to add a rule that checks if the line length is below a given threshold. Currently this PR only shows a warning if there is a line with more than 120 columns (hardcoded), without specifying which line.

[felipeasimos]

btw, just new-rule line-length didn't create src/linter/rules/line_length.zig automatically, I had to copy the examples manually

[DonIsaac]

Thanks for the PR! Some requested changes are blocked by things I need to do, which I'll add now. Please make sure you add docs, then run just ready and commit the changes.

[DonIsaac]

Add this to the rule as a field const LineLength = struct { max_length: u32 = 120 }, that way when I add rule-specific configs it will just work

[felipeasimos]

Not really sure where you would like me to put this/ how to get this value inside the runOnce function

[DonIsaac]

Check UnsafeUndefined for an example. it's config is set inside the struct itself.

pub const LineLength = struct {
  max_length: u32 = 120,
};

Then in runOnce:

pub fn runOnce(self: *const LineLength, ctx: *LinterContext) void {
  const len = getLineLength();
  if (len < self.max_len) { ... }
}

[felipeasimos]

I believe I added this properly, but I can't really test it. How would a zlint.json with an option for unsafe-undefined look like?

[DonIsaac]

Eventually (not now):

{
    "rules": {
        "max-lines": ["warn", { "max-length": 100 }]
    }
}

[DonIsaac]

btw, just new-rule line-length didn't create src/linter/rules/line_length.zig automatically, I had to copy the examples manually

I can't repro, when I run just new-rule foo I get this:

EDIT: make sure you have Bun installed.

[felipeasimos]

EDIT: make sure you have Bun installed.

Yeah, sorry, that was probably due to Bun. It failed silently so I didn't realize.

[codecov]

Codecov Report

Attention: Patch coverage is 93.54839% with 2 lines in your changes missing coverage. Please review.

Project coverage is 86.76%. Comparing base (395dd28) to head (b6ad31f).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/linter/rules/line_length.zig	93.10%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #232      +/-   ##
==========================================
+ Coverage   86.72%   86.76%   +0.04%     
==========================================
  Files          69       70       +1     
  Lines        4640     4671      +31     
==========================================
+ Hits         4024     4053      +29     
- Misses        616      618       +2     

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[DonIsaac]

Remove dead code (zlint --fix-dangerously)

[DonIsaac]

Once spans are fixed we can merge this. They should cover the entire line, not just characters >= the max length.

[felipeasimos]

I see that the tests in Windows are breaking. The rule takes into account that the newline in windows would be "\r\n", but that's probably not the case here, making it so std.mem.splitSequence doesn't match "\r\n" to split the source file. So in windows, when reading a file with "\n" as newline, this would mean that the whole source file would be seem as one giant line.

I've made it so the type of newline being used is detected using the first line in the file.

[DonIsaac]

That's a much better solution, since that will work on git bash. Thank you!