feature_request(configuration): support YAML configuration format

1. Summary

It would be nice, if Markdownlint will support configuration file in YAML format.

2. Argumentation

2.1. Comments

I can’t use comments in .markdownlintrc.

I think, that comment, why I use this or that option, is a nice practice. My .markdownlintrc file:

{
    //////////////////
    // Markdownlint //
    //////////////////
    // Lint Markdown files:
    // https://www.npmjs.com/package/markdownlint
    // Ruby Markdownlint obsolete, have bugs (see comments below)
    // and doesn't support at the time:
    // https://rubygems.org/gems/mdl
    // Markdownlint styles:
    // Rules: https://github.com/DavidAnson/markdownlint/blob/master/doc/Rules.md
    //
    //
    // [DEPRECATED] In my Pelican articles I use h1 tag in page templates
    // I begin section use h2 tag
    // Using h1 tag is good — http://archive.li/X3d8c
    // Enable, because downheader extension
    // https://github.com/cprieto/mdx_downheader
    // "MD002": false,
    // [WARNING] Rule only for spaces indentation, show errors, if using tabs. So exclude.
    "MD007": false,
    // Allowed 2 trailing spaces in line, not 1, 3 or 4:
    // https://github.com/markdownlint/markdownlint/issues/165
    "MD009": {
        "br_spaces": 2
    },
    // I prefer tabs instead of spaces:
    // https://softwareengineering.stackexchange.com/a/72/264224
    "MD010": false,
    // [DEPRECATED] In my Pelican articles I use h1 tag in page templates
    // I begin section use h2 tag
    // Using h1 tag is good — http://archive.li/X3d8c
    // Enable, because downheader extension
    // https://github.com/cprieto/mdx_downheader
    // exclude_rule 'MD0102'
    "MD013": false,
    // I use MarkdownTOC autoanchoring:
    // https://github.com/naokazuterada/MarkdownTOC#auto-anchoring-when-heading-has-anchor-defined
    "MD022": false,
    // [DONE] This option works in Node Markdownlint, not Ruby mdl:
    // I end headers with question marks:
    // [BUG] Doesn't work, if inline HTML:
    // https://github.com/markdownlint/markdownlint/issues/196
    "MD026": {
        "punctuation": ".,;:!"
    },
    // Pelican features needs inline HTML support
    "MD033": false,
    // I use bare URL for Pelican article metadata variable “Opengraphimage”.
    // Open Graph — http://ruogp.me/
    // Also, I use bare URL for magiclink:
    // http://facelessuser.github.io/pymdown-extensions/extensions/magiclink/
    "MD034": false,
    // [DONE] This option works in Node Markdownlint, not Ruby mdl:
    // [BUG] Temporary exclude rule before the new release:
    // https://github.com/mivok/markdownlint/pull/160
    // "MD039": false,
    // In Pelican articles and pages first line — is Metadata, not header
    "MD041": false
}

I use grunt-markdownlint plugin. It supports JSON configuration file:

example2: {
  options: {
    config: grunt.file.readJSON(rulesFile) //read linting rules from file
  }

grunt.file.readJSON doesn’t support comments in .markdownlintrc file → I can’t use comments in .markdownlintrc.

Grunt support parsing YAML data.

2.2. Another reasons

• JSON as configuration files: please don’t

Thanks.

[DavidAnson]

I would suggest .markdownlint.yaml. I think this may become a work item for the CLI project (where I would document it).

[DavidAnson]

Wait - for your scenario, shouldn’t you be able to switch to a YAML file today and use grunt.file.readYAML to read it into a JavaScript object?