planning

node_modules/remark-parse/lib/tokenize/reference.js

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+'use strict'
+
+var whitespace = require('is-whitespace-character')
+var locate = require('../locate/link')
+var normalize = require('../util/normalize')
+
+module.exports = reference
+reference.locator = locate
+
+var link = 'link'
+var image = 'image'
+var footnote = 'footnote'
+var shortcut = 'shortcut'
+var collapsed = 'collapsed'
+var full = 'full'
+var space = ' '
+var exclamationMark = '!'
+var leftSquareBracket = '['
+var backslash = '\\'
+var rightSquareBracket = ']'
+var caret = '^'
+
+function reference(eat, value, silent) {
+  var self = this
+  var commonmark = self.options.commonmark
+  var character = value.charAt(0)
+  var index = 0
+  var length = value.length
+  var subvalue = ''
+  var intro = ''
+  var type = link
+  var referenceType = shortcut
+  var content
+  var identifier
+  var now
+  var node
+  var exit
+  var queue
+  var bracketed
+  var depth
+
+  // Check whether we’re eating an image.
+  if (character === exclamationMark) {
+    type = image
+    intro = character
+    character = value.charAt(++index)
+  }
+
+  if (character !== leftSquareBracket) {
+    return
+  }
+
+  index++
+  intro += character
+  queue = ''
+
+  // Check whether we’re eating a footnote.
+  if (self.options.footnotes && value.charAt(index) === caret) {
+    // Exit if `![^` is found, so the `!` will be seen as text after this,
+    // and we’ll enter this function again when `[^` is found.
+    if (type === image) {
+      return
+    }
+
+    intro += caret
+    index++
+    type = footnote
+  }
+
+  // Eat the text.
+  depth = 0
+
+  while (index < length) {
+    character = value.charAt(index)
+
+    if (character === leftSquareBracket) {
+      bracketed = true
+      depth++
+    } else if (character === rightSquareBracket) {
+      if (!depth) {
+        break
+      }
+
+      depth--
+    }
+
+    if (character === backslash) {
+      queue += backslash
+      character = value.charAt(++index)
+    }
+
+    queue += character
+    index++
+  }
+
+  subvalue = queue
+  content = queue
+  character = value.charAt(index)
+
+  if (character !== rightSquareBracket) {
+    return
+  }
+
+  index++
+  subvalue += character
+  queue = ''
+
+  if (!commonmark) {
+    // The original markdown syntax definition explicitly allows for whitespace
+    // between the link text and link label; commonmark departs from this, in
+    // part to improve support for shortcut reference links
+    while (index < length) {
+      character = value.charAt(index)
+
+      if (!whitespace(character)) {
+        break
+      }
+
+      queue += character
+      index++
+    }
+  }
+
+  character = value.charAt(index)
+
+  // Inline footnotes cannot have an identifier.
+  if (type !== footnote && character === leftSquareBracket) {
+    identifier = ''
+    queue += character
+    index++
+
+    while (index < length) {
+      character = value.charAt(index)
+
+      if (character === leftSquareBracket || character === rightSquareBracket) {
+        break
+      }
+
+      if (character === backslash) {
+        identifier += backslash
+        character = value.charAt(++index)
+      }
+
+      identifier += character
+      index++
+    }
+
+    character = value.charAt(index)
+
+    if (character === rightSquareBracket) {
+      referenceType = identifier ? full : collapsed
+      queue += identifier + character
+      index++
+    } else {
+      identifier = ''
+    }
+
+    subvalue += queue
+    queue = ''
+  } else {
+    if (!content) {
+      return
+    }
+
+    identifier = content
+  }
+
+  // Brackets cannot be inside the identifier.
+  if (referenceType !== full && bracketed) {
+    return
+  }
+
+  subvalue = intro + subvalue
+
+  if (type === link && self.inLink) {
+    return null
+  }
+
+  /* istanbul ignore if - never used (yet) */
+  if (silent) {
+    return true
+  }
+
+  if (type === footnote && content.indexOf(space) !== -1) {
+    return eat(subvalue)({
+      type: footnote,
+      children: this.tokenizeInline(content, eat.now())
+    })
+  }
+
+  now = eat.now()
+  now.column += intro.length
+  now.offset += intro.length
+  identifier = referenceType === full ? identifier : content
+
+  node = {
+    type: type + 'Reference',
+    identifier: normalize(identifier),
+    label: identifier
+  }
+
+  if (type === link || type === image) {
+    node.referenceType = referenceType
+  }
+
+  if (type === link) {
+    exit = self.enterLink()
+    node.children = self.tokenizeInline(content, now)
+    exit()
+  } else if (type === image) {
+    node.alt = self.decode.raw(self.unescape(content), now) || null
+  }
+
+  return eat(subvalue)(node)
+}