Allow config to be provided via command-line

[cameronhunter]

Summary

I use lint-staged as a pre-commit hook and would like to explicitly provide the config file location. This PR uses commander to parse the command-line argument and passes it as cosmiconfig's configPath option. This allows the config file to be any format already supported.

Test plan

I've added tests and updated the documentation.

[sudo-suhas]

@cameronhunter Could you investigate the CI failures?

[codecov]

Codecov Report

Merging #304 into master will increase coverage by 4.09%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #304      +/-   ##
==========================================
+ Coverage   91.86%   95.95%   +4.09%     
==========================================
  Files          10       10              
  Lines         172      173       +1     
  Branches       26       27       +1     
==========================================
+ Hits          158      166       +8     
+ Misses         13        7       -6     
+ Partials        1        0       -1

Impacted Files	Coverage Δ
src/index.js	87.5% <100%> (+10.08%)	⬆️
src/runAll.js	92.59% <0%> (+14.81%)	⬆️

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[cameronhunter]

@sudo-suhas The CI failures were:

1. Cross-platform difference in paths between Windows and Linux. Resolved using a jest serializer.
2. In some CI setups Listr decides to be verbose and write more to the console, which meant the snapshots were inconsistent. Resolved by injecting the console logger instead of mocking the global console.

[sudo-suhas]

Hey @cameronhunter, thanks for this. I did not know about the jest snapshot serializer. Cool stuff.

Regarding 99d44b9, do you think it is possible that the whitespace issue was because the editor removed trailing whitespace? I personally have that enabled in vscode.

In some CI setups Listr decides to be verbose and write more to the console

Actually, I don't think this is the case. I am only guessing, but I think this has something to do with running the code in sync vs async. In all our current tests, since cosmiconfig was being mocked, we only captured the console logs which were printed by us. And after that listr wrote some more logs. However, in the test you added, cosmiconfig ran async and by the time we awaited for lintStaged, listr had already pushed some logs to console. For some reason, this isn't happening locally. Anyway, listr behavior isn't different but our way of capturing console logs is buggy. So I think it is the right approach to inject the logger.

However, I think a lot of complexity was added in the way it has been implemented now. I took some of your commits and tweaked them in #311. Could you please remove commits ce2c8d7, 327f1c7, 58b034a, 505654a, 40b399a, afe2fac and port the changes from d512c63 instead? You can use git reset to remove commits. Let me know if you need any help.

This branch is out-of-date with the base branch

Edit: If you could rebase this on master, that would be good too.

[cameronhunter]

@sudo-suhas I've rebased on master, squashed to a single commit and used npm run cz for formatting the commit message.

To prevent a breaking change, I reordered the parameters to the main lib to pass the logger first (with a fallback value of console). Overall this feature addition should just be a minor version bump.

CI is passing – let me know if there's anything more you'd like included before merging.

[sudo-suhas]

Could you change this to true? We'd be able to see the config in the snapshot then.

[cameronhunter]

Sure

[sudo-suhas]

Great Work @cameronhunter! LGTM.

[cameronhunter]

@sudo-suhas Can you speak to a timeline of merging and publishing the new version?

[sudo-suhas]

I figured I'd wait a couple of days for comments, if any, from @okonet and @luftywiranda13. I'll wait till end of day and merge it in. It should be released immediately via semantic-release.

[luftywiranda13]

is it better if we also add some additional helpful things for the --help page?

[sudo-suhas]

@luftywiranda13 I think that makes sense.

[sudo-suhas]

@cameronhunter This has been released in v4.3.0. Apologies for the delay and thank you for your contribution!