Updated Formatter for better metrics

[shetty-tejas]

Re-opened the previous PR: #7.

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I was making a Github Actions project for working with SimpleCov. Turns out this being the recommended gem by SimpleCov, didn't have some functionalities I was thinking of adding support for. So added it here in this PR. If you have any thoughts or suggestions do let me know 😄

What's Changed:

• Minimum Coverage Check for file. If fails, the file name and the percent_covered is collected in errors.
• Groups now contain more information such as covered_lines, missed_lines and total_lines.
• Also returns config details like minimum_coverage and minimum_coverage_by_file.
• Total metrics as default (even when groups are not available).

[shetty-tejas]

@pboling @f-moya Any changes you guys would like me to integrate?

[pboling]

LGTM

[pboling]

Ping @f-moya

[shetty-tejas]

@f-moya It has been a long time since this PR was raised. Can you check it out please? I think this is a great improvement and should be a part of any new release that would be created.

[shetty-tejas]

ping @f-moya!

[sferik]

FYI, I’m planning to merge simplecov_json_formatter into the main SimpleCov codebase, as I just did with simplecov-html.

[sferik]

@shetty-tejas I’ve merged this repo into the SimpleCov repo: simplecov-ruby/simplecov@253c19e. This repo should be archived soon. Feel free to open a version of the PR in that repo. I promise it will be reviewed quickly.

[sferik]

@shetty-tejas Thanks for this PR! Since I’ve merged simplecov_json_formatter directly into SimpleCov, I've implemented a version of these enhancements in the main repo instead.

Here’s what I kept from your proposal:

• Per-file coverage percentages
• Richer group metrics (covered, missed, total counts + percent)
• A top-level total section with aggregate stats

Here’s what I changed:

• No errors key – minimum coverage checking is already handled by SimpleCov’s exit codes, so duplicating it in the JSON would couple the formatter to configuration
• No config in meta – likewise, the formatter shouldn’t expose SimpleCov’s internal configuration
• All three coverage types – line, branch, and method coverage are all supported consistently throughout (total, groups, and per-file), not just line coverage
• Method coverage data – per-file output includes a methods array (similar to the existing branches array) when method coverage is enabled
• SimpleCov.root instead of Dir.pwd for path operations – this is more stable
• Full stats shape – total and group stats include covered, missed, total, percent, and strength (using CoverageStatistics directly), rather than ad-hoc fields

I believe this PR can be closed, since the external gem repo is no longer the right target for changes, but wanted to make sure you got credit for the contribution. Feel free to give me feedback at simplecov-ruby/simplecov#1164. Thanks again!