planning

node_modules/micromark/dist/compile/html.js

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+'use strict'
+
+var decodeEntity = require('parse-entities/decode-entity.js')
+var assign = require('../constant/assign.js')
+var hasOwnProperty = require('../constant/has-own-property.js')
+var combineHtmlExtensions = require('../util/combine-html-extensions.js')
+var chunkedPush = require('../util/chunked-push.js')
+var miniflat = require('../util/miniflat.js')
+var normalizeIdentifier = require('../util/normalize-identifier.js')
+var normalizeUri = require('../util/normalize-uri.js')
+var safeFromInt = require('../util/safe-from-int.js')
+
+function _interopDefaultLegacy(e) {
+  return e && typeof e === 'object' && 'default' in e ? e : {default: e}
+}
+
+var decodeEntity__default = /*#__PURE__*/ _interopDefaultLegacy(decodeEntity)
+
+// While micromark is a lexer/tokenizer, the common case of going from markdown
+// dealt with.
+// Technically, we can skip `>` and `"` in many cases, but CM includes them.
+
+var characterReferences = {
+  '"': 'quot',
+  '&': 'amp',
+  '<': 'lt',
+  '>': 'gt'
+} // These two are allowlists of essentially safe protocols for full URLs in
+// respectively the `href` (on `<a>`) and `src` (on `<img>`) attributes.
+// They are based on what is allowed on GitHub,
+// <https://github.com/syntax-tree/hast-util-sanitize/blob/9275b21/lib/github.json#L31>
+
+var protocolHref = /^(https?|ircs?|mailto|xmpp)$/i
+var protocolSrc = /^https?$/i
+
+function compileHtml(options) {
+  // Configuration.
+  // Includes `htmlExtensions` (an array of extensions), `defaultLineEnding` (a
+  // preferred EOL), `allowDangerousProtocol` (whether to allow potential
+  // dangerous protocols), and `allowDangerousHtml` (whether to allow potential
+  // dangerous HTML).
+  var settings = options || {} // Tags is needed because according to markdown, links and emphasis and
+  // whatnot can exist in images, however, as HTML doesn’t allow content in
+  // images, the tags are ignored in the `alt` attribute, but the content
+  // remains.
+
+  var tags = true // An object to track identifiers to media (URLs and titles) defined with
+  // definitions.
+
+  var definitions = {} // A lot of the handlers need to capture some of the output data, modify it
+  // somehow, and then deal with it.
+  // We do that by tracking a stack of buffers, that can be opened (with
+  // `buffer`) and closed (with `resume`) to access them.
+
+  var buffers = [[]] // As we can have links in images and the other way around, where the deepest
+  // ones are closed first, we need to track which one we’re in.
+
+  var mediaStack = [] // Same for tightness, which is specific to lists.
+  // We need to track if we’re currently in a tight or loose container.
+
+  var tightStack = []
+  var defaultHandlers = {
+    enter: {
+      blockQuote: onenterblockquote,
+      codeFenced: onentercodefenced,
+      codeFencedFenceInfo: buffer,
+      codeFencedFenceMeta: buffer,
+      codeIndented: onentercodeindented,
+      codeText: onentercodetext,
+      content: onentercontent,
+      definition: onenterdefinition,
+      definitionDestinationString: onenterdefinitiondestinationstring,
+      definitionLabelString: buffer,
+      definitionTitleString: buffer,
+      emphasis: onenteremphasis,
+      htmlFlow: onenterhtmlflow,
+      htmlText: onenterhtml,
+      image: onenterimage,
+      label: buffer,
+      link: onenterlink,
+      listItemMarker: onenterlistitemmarker,
+      listItemValue: onenterlistitemvalue,
+      listOrdered: onenterlistordered,
+      listUnordered: onenterlistunordered,
+      paragraph: onenterparagraph,
+      reference: buffer,
+      resource: onenterresource,
+      resourceDestinationString: onenterresourcedestinationstring,
+      resourceTitleString: buffer,
+      setextHeading: onentersetextheading,
+      strong: onenterstrong
+    },
+    exit: {
+      atxHeading: onexitatxheading,
+      atxHeadingSequence: onexitatxheadingsequence,
+      autolinkEmail: onexitautolinkemail,
+      autolinkProtocol: onexitautolinkprotocol,
+      blockQuote: onexitblockquote,
+      characterEscapeValue: onexitdata,
+      characterReferenceMarkerHexadecimal: onexitcharacterreferencemarker,
+      characterReferenceMarkerNumeric: onexitcharacterreferencemarker,
+      characterReferenceValue: onexitcharacterreferencevalue,
+      codeFenced: onexitflowcode,
+      codeFencedFence: onexitcodefencedfence,
+      codeFencedFenceInfo: onexitcodefencedfenceinfo,
+      codeFencedFenceMeta: resume,
+      codeFlowValue: onexitcodeflowvalue,
+      codeIndented: onexitflowcode,
+      codeText: onexitcodetext,
+      codeTextData: onexitdata,
+      data: onexitdata,
+      definition: onexitdefinition,
+      definitionDestinationString: onexitdefinitiondestinationstring,
+      definitionLabelString: onexitdefinitionlabelstring,
+      definitionTitleString: onexitdefinitiontitlestring,
+      emphasis: onexitemphasis,
+      hardBreakEscape: onexithardbreak,
+      hardBreakTrailing: onexithardbreak,
+      htmlFlow: onexithtml,
+      htmlFlowData: onexitdata,
+      htmlText: onexithtml,
+      htmlTextData: onexitdata,
+      image: onexitmedia,
+      label: onexitlabel,
+      labelText: onexitlabeltext,
+      lineEnding: onexitlineending,
+      link: onexitmedia,
+      listOrdered: onexitlistordered,
+      listUnordered: onexitlistunordered,
+      paragraph: onexitparagraph,
+      reference: resume,
+      referenceString: onexitreferencestring,
+      resource: resume,
+      resourceDestinationString: onexitresourcedestinationstring,
+      resourceTitleString: onexitresourcetitlestring,
+      setextHeading: onexitsetextheading,
+      setextHeadingLineSequence: onexitsetextheadinglinesequence,
+      setextHeadingText: onexitsetextheadingtext,
+      strong: onexitstrong,
+      thematicBreak: onexitthematicbreak
+    }
+  } // Combine the HTML extensions with the default handlers.
+  // An HTML extension is an object whose fields are either `enter` or `exit`
+  // (reflecting whether a token is entered or exited).
+  // The values at such objects are names of tokens mapping to handlers.
+  // Handlers are called, respectively when a token is opener or closed, with
+  // that token, and a context as `this`.
+
+  var handlers = combineHtmlExtensions(
+    [defaultHandlers].concat(miniflat(settings.htmlExtensions))
+  ) // Handlers do often need to keep track of some state.
+  // That state is provided here as a key-value store (an object).
+
+  var data = {
+    tightStack: tightStack
+  } // The context for handlers references a couple of useful functions.
+  // In handlers from extensions, those can be accessed at `this`.
+  // For the handlers here, they can be accessed directly.
+
+  var context = {
+    lineEndingIfNeeded: lineEndingIfNeeded,
+    options: settings,
+    encode: encode,
+    raw: raw,
+    tag: tag,
+    buffer: buffer,
+    resume: resume,
+    setData: setData,
+    getData: getData
+  } // Generally, micromark copies line endings (`'\r'`, `'\n'`, `'\r\n'`) in the
+  // markdown document over to the compiled HTML.
+  // In some cases, such as `> a`, CommonMark requires that extra line endings
+  // are added: `<blockquote>\n<p>a</p>\n</blockquote>`.
+  // This variable hold the default line ending when given (or `undefined`),
+  // and in the latter case will be updated to the first found line ending if
+  // there is one.
+
+  var lineEndingStyle = settings.defaultLineEnding // Return the function that handles a slice of events.
+
+  return compile // Deal w/ a slice of events.
+  // Return either the empty string if there’s nothing of note to return, or the
+  // result when done.
+
+  function compile(events) {
+    // As definitions can come after references, we need to figure out the media
+    // (urls and titles) defined by them before handling the references.
+    // So, we do sort of what HTML does: put metadata at the start (in head), and
+    // then put content after (`body`).
+    var head = []
+    var body = []
+    var index
+    var start
+    var listStack
+    var handler
+    var result
+    index = -1
+    start = 0
+    listStack = []
+
+    while (++index < events.length) {
+      // Figure out the line ending style used in the document.
+      if (
+        !lineEndingStyle &&
+        (events[index][1].type === 'lineEnding' ||
+          events[index][1].type === 'lineEndingBlank')
+      ) {
+        lineEndingStyle = events[index][2].sliceSerialize(events[index][1])
+      } // Preprocess lists to infer whether the list is loose or not.
+
+      if (
+        events[index][1].type === 'listOrdered' ||
+        events[index][1].type === 'listUnordered'
+      ) {
+        if (events[index][0] === 'enter') {
+          listStack.push(index)
+        } else {
+          prepareList(events.slice(listStack.pop(), index))
+        }
+      } // Move definitions to the front.
+
+      if (events[index][1].type === 'definition') {
+        if (events[index][0] === 'enter') {
+          body = chunkedPush(body, events.slice(start, index))
+          start = index
+        } else {
+          head = chunkedPush(head, events.slice(start, index + 1))
+          start = index + 1
+        }
+      }
+    }
+
+    head = chunkedPush(head, body)
+    head = chunkedPush(head, events.slice(start))
+    result = head
+    index = -1 // Handle the start of the document, if defined.
+
+    if (handlers.enter.null) {
+      handlers.enter.null.call(context)
+    } // Handle all events.
+
+    while (++index < events.length) {
+      handler = handlers[result[index][0]]
+
+      if (hasOwnProperty.call(handler, result[index][1].type)) {
+        handler[result[index][1].type].call(
+          assign(
+            {
+              sliceSerialize: result[index][2].sliceSerialize
+            },
+            context
+          ),
+          result[index][1]
+        )
+      }
+    } // Handle the end of the document, if defined.
+
+    if (handlers.exit.null) {
+      handlers.exit.null.call(context)
+    }
+
+    return buffers[0].join('')
+  } // Figure out whether lists are loose or not.
+
+  function prepareList(slice) {
+    var length = slice.length - 1 // Skip close.
+
+    var index = 0 // Skip open.
+
+    var containerBalance = 0
+    var loose
+    var atMarker
+    var event
+
+    while (++index < length) {
+      event = slice[index]
+
+      if (event[1]._container) {
+        atMarker = undefined
+
+        if (event[0] === 'enter') {
+          containerBalance++
+        } else {
+          containerBalance--
+        }
+      } else if (event[1].type === 'listItemPrefix') {
+        if (event[0] === 'exit') {
+          atMarker = true
+        }
+      } else if (event[1].type === 'linePrefix');
+      else if (event[1].type === 'lineEndingBlank') {
+        if (event[0] === 'enter' && !containerBalance) {
+          if (atMarker) {
+            atMarker = undefined
+          } else {
+            loose = true
+          }
+        }
+      } else {
+        atMarker = undefined
+      }
+    }
+
+    slice[0][1]._loose = loose
+  } // Set data into the key-value store.
+
+  function setData(key, value) {
+    data[key] = value
+  } // Get data from the key-value store.
+
+  function getData(key) {
+    return data[key]
+  } // Capture some of the output data.
+
+  function buffer() {
+    buffers.push([])
+  } // Stop capturing and access the output data.
+
+  function resume() {
+    return buffers.pop().join('')
+  } // Output (parts of) HTML tags.
+
+  function tag(value) {
+    if (!tags) return
+    setData('lastWasTag', true)
+    buffers[buffers.length - 1].push(value)
+  } // Output raw data.
+
+  function raw(value) {
+    setData('lastWasTag')
+    buffers[buffers.length - 1].push(value)
+  } // Output an extra line ending.
+
+  function lineEnding() {
+    raw(lineEndingStyle || '\n')
+  } // Output an extra line ending if the previous value wasn’t EOF/EOL.
+
+  function lineEndingIfNeeded() {
+    var buffer = buffers[buffers.length - 1]
+    var slice = buffer[buffer.length - 1]
+    var previous = slice ? slice.charCodeAt(slice.length - 1) : null
+
+    if (previous === 10 || previous === 13 || previous === null) {
+      return
+    }
+
+    lineEnding()
+  } // Make a value safe for injection in HTML (except w/ `ignoreEncode`).
+
+  function encode(value) {
+    return getData('ignoreEncode') ? value : value.replace(/["&<>]/g, replace)
+
+    function replace(value) {
+      return '&' + characterReferences[value] + ';'
+    }
+  } // Make a value safe for injection as a URL.
+  // This does encode unsafe characters with percent-encoding, skipping already
+  // encoded sequences (`normalizeUri`).
+  // Further unsafe characters are encoded as character references (`encode`).
+  // Finally, if the URL includes an unknown protocol (such as a dangerous
+  // example, `javascript:`), the value is ignored.
+
+  function url(url, protocol) {
+    var value = encode(normalizeUri(url || ''))
+    var colon = value.indexOf(':')
+    var questionMark = value.indexOf('?')
+    var numberSign = value.indexOf('#')
+    var slash = value.indexOf('/')
+
+    if (
+      settings.allowDangerousProtocol || // If there is no protocol, it’s relative.
+      colon < 0 || // If the first colon is after a `?`, `#`, or `/`, it’s not a protocol.
+      (slash > -1 && colon > slash) ||
+      (questionMark > -1 && colon > questionMark) ||
+      (numberSign > -1 && colon > numberSign) || // It is a protocol, it should be allowed.
+      protocol.test(value.slice(0, colon))
+    ) {
+      return value
+    }
+
+    return ''
+  } //
+  // Handlers.
+  //
+
+  function onenterlistordered(token) {
+    tightStack.push(!token._loose)
+    lineEndingIfNeeded()
+    tag('<ol')
+    setData('expectFirstItem', true)
+  }
+
+  function onenterlistunordered(token) {
+    tightStack.push(!token._loose)
+    lineEndingIfNeeded()
+    tag('<ul')
+    setData('expectFirstItem', true)
+  }
+
+  function onenterlistitemvalue(token) {
+    var value
+
+    if (getData('expectFirstItem')) {
+      value = parseInt(this.sliceSerialize(token), 10)
+
+      if (value !== 1) {
+        tag(' start="' + encode(String(value)) + '"')
+      }
+    }
+  }
+
+  function onenterlistitemmarker() {
+    if (getData('expectFirstItem')) {
+      tag('>')
+    } else {
+      onexitlistitem()
+    }
+
+    lineEndingIfNeeded()
+    tag('<li>')
+    setData('expectFirstItem') // “Hack” to prevent a line ending from showing up if the item is empty.
+
+    setData('lastWasTag')
+  }
+
+  function onexitlistordered() {
+    onexitlistitem()
+    tightStack.pop()
+    lineEnding()
+    tag('</ol>')
+  }
+
+  function onexitlistunordered() {
+    onexitlistitem()
+    tightStack.pop()
+    lineEnding()
+    tag('</ul>')
+  }
+
+  function onexitlistitem() {
+    if (getData('lastWasTag') && !getData('slurpAllLineEndings')) {
+      lineEndingIfNeeded()
+    }
+
+    tag('</li>')
+    setData('slurpAllLineEndings')
+  }
+
+  function onenterblockquote() {
+    tightStack.push(false)
+    lineEndingIfNeeded()
+    tag('<blockquote>')
+  }
+
+  function onexitblockquote() {
+    tightStack.pop()
+    lineEndingIfNeeded()
+    tag('</blockquote>')
+    setData('slurpAllLineEndings')
+  }
+
+  function onenterparagraph() {
+    if (!tightStack[tightStack.length - 1]) {
+      lineEndingIfNeeded()
+      tag('<p>')
+    }
+
+    setData('slurpAllLineEndings')
+  }
+
+  function onexitparagraph() {
+    if (tightStack[tightStack.length - 1]) {
+      setData('slurpAllLineEndings', true)
+    } else {
+      tag('</p>')
+    }
+  }
+
+  function onentercodefenced() {
+    lineEndingIfNeeded()
+    tag('<pre><code')
+    setData('fencesCount', 0)
+  }
+
+  function onexitcodefencedfenceinfo() {
+    var value = resume()
+    tag(' class="language-' + value + '"')
+  }
+
+  function onexitcodefencedfence() {
+    if (!getData('fencesCount')) {
+      tag('>')
+      setData('fencedCodeInside', true)
+      setData('slurpOneLineEnding', true)
+    }
+
+    setData('fencesCount', getData('fencesCount') + 1)
+  }
+
+  function onentercodeindented() {
+    lineEndingIfNeeded()
+    tag('<pre><code>')
+  }
+
+  function onexitflowcode() {
+    // Send an extra line feed if we saw data.
+    if (getData('flowCodeSeenData')) lineEndingIfNeeded()
+    tag('</code></pre>')
+    if (getData('fencesCount') < 2) lineEndingIfNeeded()
+    setData('flowCodeSeenData')
+    setData('fencesCount')
+    setData('slurpOneLineEnding')
+  }
+
+  function onenterimage() {
+    mediaStack.push({
+      image: true
+    })
+    tags = undefined // Disallow tags.
+  }
+
+  function onenterlink() {
+    mediaStack.push({})
+  }
+
+  function onexitlabeltext(token) {
+    mediaStack[mediaStack.length - 1].labelId = this.sliceSerialize(token)
+  }
+
+  function onexitlabel() {
+    mediaStack[mediaStack.length - 1].label = resume()
+  }
+
+  function onexitreferencestring(token) {
+    mediaStack[mediaStack.length - 1].referenceId = this.sliceSerialize(token)
+  }
+
+  function onenterresource() {
+    buffer() // We can have line endings in the resource, ignore them.
+
+    mediaStack[mediaStack.length - 1].destination = ''
+  }
+
+  function onenterresourcedestinationstring() {
+    buffer() // Ignore encoding the result, as we’ll first percent encode the url and
+    // encode manually after.
+
+    setData('ignoreEncode', true)
+  }
+
+  function onexitresourcedestinationstring() {
+    mediaStack[mediaStack.length - 1].destination = resume()
+    setData('ignoreEncode')
+  }
+
+  function onexitresourcetitlestring() {
+    mediaStack[mediaStack.length - 1].title = resume()
+  }
+
+  function onexitmedia() {
+    var index = mediaStack.length - 1 // Skip current.
+
+    var media = mediaStack[index]
+    var context =
+      media.destination === undefined
+        ? definitions[normalizeIdentifier(media.referenceId || media.labelId)]
+        : media
+    tags = true
+
+    while (index--) {
+      if (mediaStack[index].image) {
+        tags = undefined
+        break
+      }
+    }
+
+    if (media.image) {
+      tag('<img src="' + url(context.destination, protocolSrc) + '" alt="')
+      raw(media.label)
+      tag('"')
+    } else {
+      tag('<a href="' + url(context.destination, protocolHref) + '"')
+    }
+
+    tag(context.title ? ' title="' + context.title + '"' : '')
+
+    if (media.image) {
+      tag(' />')
+    } else {
+      tag('>')
+      raw(media.label)
+      tag('</a>')
+    }
+
+    mediaStack.pop()
+  }
+
+  function onenterdefinition() {
+    buffer()
+    mediaStack.push({})
+  }
+
+  function onexitdefinitionlabelstring(token) {
+    // Discard label, use the source content instead.
+    resume()
+    mediaStack[mediaStack.length - 1].labelId = this.sliceSerialize(token)
+  }
+
+  function onenterdefinitiondestinationstring() {
+    buffer()
+    setData('ignoreEncode', true)
+  }
+
+  function onexitdefinitiondestinationstring() {
+    mediaStack[mediaStack.length - 1].destination = resume()
+    setData('ignoreEncode')
+  }
+
+  function onexitdefinitiontitlestring() {
+    mediaStack[mediaStack.length - 1].title = resume()
+  }
+
+  function onexitdefinition() {
+    var id = normalizeIdentifier(mediaStack[mediaStack.length - 1].labelId)
+    resume()
+
+    if (!hasOwnProperty.call(definitions, id)) {
+      definitions[id] = mediaStack[mediaStack.length - 1]
+    }
+
+    mediaStack.pop()
+  }
+
+  function onentercontent() {
+    setData('slurpAllLineEndings', true)
+  }
+
+  function onexitatxheadingsequence(token) {
+    // Exit for further sequences.
+    if (getData('headingRank')) return
+    setData('headingRank', this.sliceSerialize(token).length)
+    lineEndingIfNeeded()
+    tag('<h' + getData('headingRank') + '>')
+  }
+
+  function onentersetextheading() {
+    buffer()
+    setData('slurpAllLineEndings')
+  }
+
+  function onexitsetextheadingtext() {
+    setData('slurpAllLineEndings', true)
+  }
+
+  function onexitatxheading() {
+    tag('</h' + getData('headingRank') + '>')
+    setData('headingRank')
+  }
+
+  function onexitsetextheadinglinesequence(token) {
+    setData(
+      'headingRank',
+      this.sliceSerialize(token).charCodeAt(0) === 61 ? 1 : 2
+    )
+  }
+
+  function onexitsetextheading() {
+    var value = resume()
+    lineEndingIfNeeded()
+    tag('<h' + getData('headingRank') + '>')
+    raw(value)
+    tag('</h' + getData('headingRank') + '>')
+    setData('slurpAllLineEndings')
+    setData('headingRank')
+  }
+
+  function onexitdata(token) {
+    raw(encode(this.sliceSerialize(token)))
+  }
+
+  function onexitlineending(token) {
+    if (getData('slurpAllLineEndings')) {
+      return
+    }
+
+    if (getData('slurpOneLineEnding')) {
+      setData('slurpOneLineEnding')
+      return
+    }
+
+    if (getData('inCodeText')) {
+      raw(' ')
+      return
+    }
+
+    raw(encode(this.sliceSerialize(token)))
+  }
+
+  function onexitcodeflowvalue(token) {
+    raw(encode(this.sliceSerialize(token)))
+    setData('flowCodeSeenData', true)
+  }
+
+  function onexithardbreak() {
+    tag('<br />')
+  }
+
+  function onenterhtmlflow() {
+    lineEndingIfNeeded()
+    onenterhtml()
+  }
+
+  function onexithtml() {
+    setData('ignoreEncode')
+  }
+
+  function onenterhtml() {
+    if (settings.allowDangerousHtml) {
+      setData('ignoreEncode', true)
+    }
+  }
+
+  function onenteremphasis() {
+    tag('<em>')
+  }
+
+  function onenterstrong() {
+    tag('<strong>')
+  }
+
+  function onentercodetext() {
+    setData('inCodeText', true)
+    tag('<code>')
+  }
+
+  function onexitcodetext() {
+    setData('inCodeText')
+    tag('</code>')
+  }
+
+  function onexitemphasis() {
+    tag('</em>')
+  }
+
+  function onexitstrong() {
+    tag('</strong>')
+  }
+
+  function onexitthematicbreak() {
+    lineEndingIfNeeded()
+    tag('<hr />')
+  }
+
+  function onexitcharacterreferencemarker(token) {
+    setData('characterReferenceType', token.type)
+  }
+
+  function onexitcharacterreferencevalue(token) {
+    var value = this.sliceSerialize(token)
+    value = getData('characterReferenceType')
+      ? safeFromInt(
+          value,
+          getData('characterReferenceType') ===
+            'characterReferenceMarkerNumeric'
+            ? 10
+            : 16
+        )
+      : decodeEntity__default['default'](value)
+    raw(encode(value))
+    setData('characterReferenceType')
+  }
+
+  function onexitautolinkprotocol(token) {
+    var uri = this.sliceSerialize(token)
+    tag('<a href="' + url(uri, protocolHref) + '">')
+    raw(encode(uri))
+    tag('</a>')
+  }
+
+  function onexitautolinkemail(token) {
+    var uri = this.sliceSerialize(token)
+    tag('<a href="' + url('mailto:' + uri, protocolHref) + '">')
+    raw(encode(uri))
+    tag('</a>')
+  }
+}
+
+module.exports = compileHtml