Add yaml linter

[asantos00]

Description of changes:
This adds the capacity to lint yaml files. I would love to hear your opinion on this, if it makes sense, if it looks correct, and so on.

It also adds a browserified version of yaml-lint (https://www.npmjs.com/package/yaml-lint) that is needed in yaml-lint.js

Notes

• Still missing tests (will add them later today)

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov]

Codecov Report

Merging #3979 (56b591b) into master (fbe3b69) will increase coverage by 0.44%.
The diff coverage is 86.56%.

@@            Coverage Diff             @@
##           master    #3979      +/-   ##
==========================================
+ Coverage   69.50%   69.94%   +0.44%     
==========================================
  Files         517      559      +42     
  Lines       50163    58336    +8173     
  Branches     9461    11233    +1772     
==========================================
+ Hits        34866    40805    +5939     
- Misses      15297    17531    +2234     

Flag	Coverage Δ
unittests	69.94% <86.56%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
lib/ace/mode/yaml/yaml-lint.js	40.91% <ø> (ø)
lib/ace/mode/yaml.js	75.00% <77.77%> (+4.62%)	⬆️
lib/ace/mode/yaml_worker.js	84.00% <84.00%> (ø)
lib/ace/mode/yaml_worker_test.js	90.90% <90.90%> (ø)
lib/ace/mode/vbscript.js	88.04% <0.00%> (-11.96%)	⬇️
lib/ace/worker/mirror.js	51.35% <0.00%> (-9.26%)	⬇️
lib/ace/mode/ruby.js	89.09% <0.00%> (-4.25%)	⬇️
lib/ace/lib/app_config.js	73.86% <0.00%> (-4.19%)	⬇️
lib/ace/layer/cursor.js	84.13% <0.00%> (-2.20%)	⬇️
lib/ace/keyboard/sublime.js	55.68% <0.00%> (-1.47%)	⬇️
... and 213 more

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[nightwing]

Thanks, this looks good! Could you tell what command did you use to create the browserified version?

[asantos00]

Hi @nightwing, thank you! I think I've used browserify yaml-lint.js --outfile yaml-lint.js --standalone lint. What am I supposed to use? Because I see I'm having some problems on the build 😞

[rushtehrani]

Is there a plan to merge this?

[lynette-li]

@nightwing
Is there a plan to merge this?
I need this feature

[asantos00]

I guess I need to do some changes but I'd need help to understand what should I do in order to get a proper browserified version 🤷‍♂

[huizluo]

i need this feature

[andrewnester]

@asantos00 I think everything is okay with your browserfied version, you can just add it to this file so eslint won't validate it
https://github.com/ajaxorg/ace/blob/master/.eslintignore

[asantos00]

@andrewnester sorry, my bad I didn't notice. I've added that to eslintignore, let me know if you need any other changes (also I need your approval for the workflows to run)

[andrewnester]

Merged! Thanks a lot for your contribution