.

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true

.gitignore

@@ -0,0 +1,6 @@
+.DS_Store
+*.log
+.nyc_output/
+coverage/
+node_modules/
+yarn.lock

.npmrc

@@ -0,0 +1 @@
+package-lock=false

.prettierignore

@@ -0,0 +1,4 @@
+coverage/
+*.html
+*.json
+*.md

.remarkignore

@@ -0,0 +1 @@
+test/

.travis.yml

@@ -0,0 +1,5 @@
+language: node_js
+node_js:
+  - lts/dubnium
+  - node
+after_script: bash <(curl -s https://codecov.io/bash)

html.js

@@ -0,0 +1 @@
+module.exports = require('./lib/html')

index.js

@@ -0,0 +1 @@
+module.exports = require('./lib/syntax')

lib/html.js

@@ -0,0 +1,10 @@
+exports.enter = {strikethrough: onenterstrikethrough}
+exports.exit = {strikethrough: onexitstrikethrough}
+
+function onenterstrikethrough() {
+  this.tag('<del>')
+}
+
+function onexitstrikethrough() {
+  this.tag('</del>')
+}

lib/syntax.js

@@ -0,0 +1,156 @@
+var classifyCharacter = require('micromark/dist/util/classify-character')
+var shallow = require('micromark/dist/util/shallow')
+var resolveAll = require('micromark/dist/util/resolve-all')
+
+var characterGroupPunctuation = 2
+
+var tokenizer = {
+  tokenize: tokenizeStrikethrough,
+  resolveAll: resolveAllStrikethrough
+}
+
+exports.text = {126: tokenizer}
+exports.insideSpan = {null: tokenizer}
+
+// Take events and resolve strikethrough.
+function resolveAllStrikethrough(events, context) {
+  var length = events.length
+  var index = -1
+  var strikethrough
+  var opening
+  var closing
+  var text
+  var indexOpen
+  var eventsUpTo
+
+  // Walk through all events.
+  while (++index < length) {
+    closing = events[index][1]
+
+    // Find a token that can close.
+    if (closing.type === 'strikethroughSequenceTemporary' && closing._close) {
+      indexOpen = index
+
+      // Now walk back to find an opener.
+      while (indexOpen--) {
+        opening = events[indexOpen][1]
+
+        // Find a token that can open the closer.
+        if (
+          opening.type === 'strikethroughSequenceTemporary' &&
+          opening._open &&
+          closing.end.offset - closing.start.offset ===
+            opening.end.offset - opening.start.offset &&
+          !(closing._open || opening._close)
+        ) {
+          closing.type = 'strikethroughSequence'
+          opening.type = 'strikethroughSequence'
+
+          strikethrough = {
+            type: 'strikethrough',
+            start: shallow(opening.start),
+            end: shallow(closing.end)
+          }
+
+          text = {
+            type: 'strikethroughText',
+            start: shallow(opening.end),
+            end: shallow(closing.start)
+          }
+
+          eventsUpTo = [].concat(
+            // Before.
+            events.slice(0, indexOpen - 1),
+            // Opening.
+            [
+              ['enter', strikethrough, context],
+              ['enter', opening, context],
+              ['exit', opening, context],
+              ['enter', text, context]
+            ],
+            // Between.
+            resolveAll(
+              context.parser.constructs.insideSpan.null,
+              events.slice(indexOpen + 1, index),
+              context
+            ),
+            // Closing.
+            [
+              ['exit', text, context],
+              ['enter', closing, context],
+              ['exit', closing, context],
+              ['exit', strikethrough, context]
+            ]
+          )
+
+          // After.
+          events = eventsUpTo.concat(events.slice(index + 2))
+          length = events.length
+          index = eventsUpTo.length - 1
+          break
+        }
+      }
+    }
+  }
+
+  return removeRemainingSequences(events)
+}
+
+function removeRemainingSequences(events) {
+  var index = -1
+  var length = events.length
+
+  while (++index < length) {
+    if (events[index][1].type === 'strikethroughSequenceTemporary') {
+      events[index][1].type = 'data'
+    }
+  }
+
+  return events
+}
+
+function tokenizeStrikethrough(effects, ok, nok) {
+  var previous = this.previous
+  var events = this.events
+  var size = 0
+
+  return start
+
+  function start(code) {
+    if (
+      code !== 126 ||
+      (previous === 126 &&
+        events[events.length - 1][1].type !== 'characterEscape')
+    ) {
+      return nok(code)
+    }
+
+    effects.enter('strikethroughSequenceTemporary')
+    return more(code)
+  }
+
+  function more(code) {
+    var token
+    var before
+    var after
+
+    if (code === 126) {
+      // If this is the third marker, exit.
+      if (size > 1) {
+        return nok(code)
+      }
+
+      effects.consume(code)
+      size++
+      return more
+    }
+
+    before = classifyCharacter(previous)
+    after = classifyCharacter(code)
+    token = effects.exit('strikethroughSequenceTemporary')
+    token._open = !after || (before && after === characterGroupPunctuation)
+    token._close = !before || (after && before === characterGroupPunctuation)
+
+    return ok(code)
+  }
+}

license

@@ -0,0 +1,22 @@
+(The MIT License)
+
+Copyright (c) 2020 Titus Wormer <[email protected]>
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+'Software'), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

package.json

@@ -0,0 +1,75 @@
+{
+  "name": "micromark-extension-gfm-strikethrough",
+  "version": "0.0.0",
+  "description": "micromark extension to support GFM strikethrough",
+  "license": "MIT",
+  "keywords": [
+    "micromark",
+    "micromark-extension",
+    "strikethrough",
+    "strike",
+    "through",
+    "del",
+    "delete",
+    "deletion",
+    "gfm",
+    "markdown",
+    "unified"
+  ],
+  "repository": "micromark/micromark-extension-gfm-strikethrough",
+  "bugs": "https://github.com/micromark/micromark-extension-gfm-strikethrough/issues",
+  "funding": {
+    "type": "opencollective",
+    "url": "https://opencollective.com/unified"
+  },
+  "author": "Titus Wormer <[email protected]> (https://wooorm.com)",
+  "contributors": [
+    "Titus Wormer <[email protected]> (https://wooorm.com)"
+  ],
+  "files": [
+    "lib/",
+    "index.js",
+    "html.js"
+  ],
+  "dependencies": {
+    "fault": "^1.0.0",
+    "micromark": "^2.3.0"
+  },
+  "devDependencies": {
+    "nyc": "^15.0.0",
+    "prettier": "^2.0.0",
+    "remark-cli": "^8.0.0",
+    "remark-preset-wooorm": "^7.0.0",
+    "tape": "^5.0.0",
+    "xo": "^0.33.0"
+  },
+  "scripts": {
+    "format": "remark . -qfo && prettier . -w --loglevel warn && xo --fix",
+    "test-api": "node test",
+    "test-coverage": "nyc --reporter lcov tape test/index.js",
+    "test": "npm run format && npm run test-coverage"
+  },
+  "nyc": {
+    "check-coverage": true,
+    "lines": 100,
+    "functions": 100,
+    "branches": 100
+  },
+  "prettier": {
+    "tabWidth": 2,
+    "useTabs": false,
+    "singleQuote": true,
+    "bracketSpacing": false,
+    "semi": false,
+    "trailingComma": "none"
+  },
+  "xo": {
+    "prettier": true,
+    "esnext": false
+  },
+  "remarkConfig": {
+    "plugins": [
+      "preset-wooorm"
+    ]
+  }
+}