refractor/lang/yaml.js

Lightweight, robust, elegant virtual syntax highlighting using Prism

// @ts-nocheck
/**
 * @import {Refractor} from '../lib/core.js'
 */
yaml.displayName = 'yaml'
yaml.aliases = ['yml']

/** @param {Refractor} Prism */
export default function yaml(Prism) {
  ;(function (Prism) {
    // https://yaml.org/spec/1.2/spec.html#c-ns-anchor-property
    // https://yaml.org/spec/1.2/spec.html#c-ns-alias-node
    var anchorOrAlias = /[*&][^\s[\]{},]+/
    // https://yaml.org/spec/1.2/spec.html#c-ns-tag-property
    var tag =
      /!(?:<[\w\-%#;/?:@&=+$,.!~*'()[\]]+>|(?:[a-zA-Z\d-]*!)?[\w\-%#;/?:@&=+$.~*'()]+)?/
    // https://yaml.org/spec/1.2/spec.html#c-ns-properties(n,c)
    var properties =
      '(?:' +
      tag.source +
      '(?:[ \t]+' +
      anchorOrAlias.source +
      ')?|' +
      anchorOrAlias.source +
      '(?:[ \t]+' +
      tag.source +
      ')?)'
    // https://yaml.org/spec/1.2/spec.html#ns-plain(n,c)
    // This is a simplified version that doesn't support "#" and multiline keys
    // All these long scarry character classes are simplified versions of YAML's characters
    var plainKey =
      /(?:[^\s\x00-\x08\x0e-\x1f!"#%&'*,\-:>?@[\]`{|}\x7f-\x84\x86-\x9f\ud800-\udfff\ufffe\uffff]|[?:-]<PLAIN>)(?:[ \t]*(?:(?![#:])<PLAIN>|:<PLAIN>))*/.source.replace(
        /<PLAIN>/g,
        function () {
          return /[^\s\x00-\x08\x0e-\x1f,[\]{}\x7f-\x84\x86-\x9f\ud800-\udfff\ufffe\uffff]/
            .source
        }
      )
    var string = /"(?:[^"\\\r\n]|\\.)*"|'(?:[^'\\\r\n]|\\.)*'/.source

    /**
     *
     * @param {string} value
     * @param {string} [flags]
     * @returns {RegExp}
     */
    function createValuePattern(value, flags) {
      flags = (flags || '').replace(/m/g, '') + 'm' // add m flag
      var pattern =
        /([:\-,[{]\s*(?:\s<<prop>>[ \t]+)?)(?:<<value>>)(?=[ \t]*(?:$|,|\]|\}|(?:[\r\n]\s*)?#))/.source
          .replace(/<<prop>>/g, function () {
            return properties
          })
          .replace(/<<value>>/g, function () {
            return value
          })
      return RegExp(pattern, flags)
    }
    Prism.languages.yaml = {
      scalar: {
        pattern: RegExp(
          /([\-:]\s*(?:\s<<prop>>[ \t]+)?[|>])[ \t]*(?:((?:\r?\n|\r)[ \t]+)\S[^\r\n]*(?:\2[^\r\n]+)*)/.source.replace(
            /<<prop>>/g,
            function () {
              return properties
            }
          )
        ),
        lookbehind: true,
        alias: 'string'
      },
      comment: /#.*/,
      key: {
        pattern: RegExp(
          /((?:^|[:\-,[{\r\n?])[ \t]*(?:<<prop>>[ \t]+)?)<<key>>(?=\s*:\s)/.source
            .replace(/<<prop>>/g, function () {
              return properties
            })
            .replace(/<<key>>/g, function () {
              return '(?:' + plainKey + '|' + string + ')'
            })
        ),
        lookbehind: true,
        greedy: true,
        alias: 'atrule'
      },
      directive: {
        pattern: /(^[ \t]*)%.+/m,
        lookbehind: true,
        alias: 'important'
      },
      datetime: {
        pattern: createValuePattern(
          /\d{4}-\d\d?-\d\d?(?:[tT]|[ \t]+)\d\d?:\d{2}:\d{2}(?:\.\d*)?(?:[ \t]*(?:Z|[-+]\d\d?(?::\d{2})?))?|\d{4}-\d{2}-\d{2}|\d\d?:\d{2}(?::\d{2}(?:\.\d*)?)?/
            .source
        ),
        lookbehind: true,
        alias: 'number'
      },
      boolean: {
        pattern: createValuePattern(/false|true/.source, 'i'),
        lookbehind: true,
        alias: 'important'
      },
      null: {
        pattern: createValuePattern(/null|~/.source, 'i'),
        lookbehind: true,
        alias: 'important'
      },
      string: {
        pattern: createValuePattern(string),
        lookbehind: true,
        greedy: true
      },
      number: {
        pattern: createValuePattern(
          /[+-]?(?:0x[\da-f]+|0o[0-7]+|(?:\d+(?:\.\d*)?|\.\d+)(?:e[+-]?\d+)?|\.inf|\.nan)/
            .source,
          'i'
        ),
        lookbehind: true
      },
      tag: tag,
      important: anchorOrAlias,
      punctuation: /---|[:[\]{}\-,|>?]|\.\.\./
    }
    Prism.languages.yml = Prism.languages.yaml
  })(Prism)
}