Do not remove escaping from brackets

js/editor.js.LICENSE.txt

@@ -292,3 +292,23 @@
  */
 
 /*! regenerator-runtime -- Copyright (c) 2014-present, Facebook, Inc. -- license (MIT): https://github.com/facebook/regenerator/blob/main/LICENSE */
+
+/**
+ * @copyright Copyright (c) 2022
+ *
+ * @license AGPL-3.0-or-later
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */

src/extensions/KeepSyntax.js

@@ -0,0 +1,47 @@
+const { Mark } = require('@tiptap/core')
+
+/**
+ * Keep markdown untouched
+ */
+const KeepSyntax = Mark.create({
+	name: 'keep-syntax',
+	parseHTML() {
+		return [
+			{
+				tag: 'span.keep-md',
+			},
+		]
+	},
+	renderHTML() {
+		return ['span', { class: 'keep-md' }, 0]
+	},
+	toMarkdown: {
+		open: '',
+		close: '',
+		mixable: true,
+		escape: false,
+		expelEnclosingWhitespace: true,
+	},
+
+	/**
+	 * Remove mark if there were manual changes
+	 */
+	onUpdate() {
+		const tr = this.editor.state.tr
+
+		this.editor.state.doc.descendants((node, pos, parent, index) => {
+			if (node.marks.findIndex(mark => mark.type.name === this.name) !== -1) {
+				if (node.type.name !== 'text' || node.text.length !== 1) {
+					tr.removeMark(pos, pos + node.nodeSize, this.type)
+				}
+			}
+		})
+		if (tr.docChanged) {
+			tr.setMeta('addToHistory', false)
+			tr.setMeta('preventUpdate', true)
+			this.editor.view.dispatch(tr)
+		}
+	},
+})
+
+export default KeepSyntax

src/extensions/Markdown.js

@@ -79,8 +79,6 @@ const createMarkdownSerializer = ({ nodes, marks }) => {
 		),
 		serialize(content, options) {
 			return this.serializer.serialize(content, { ...options, tightLists: true })
-				.split('\\[').join('[')
-				.split('\\]').join(']')
 		},
 	}
 }

src/extensions/RichText.js

@@ -34,6 +34,7 @@ import CodeBlock from '@tiptap/extension-code-block'
 import HorizontalRule from '@tiptap/extension-horizontal-rule'
 import Dropcursor from '@tiptap/extension-dropcursor'
 import HardBreak from './HardBreak.js'
+import KeepSyntax from './KeepSyntax.js'
 import Table from './../nodes/Table.js'
 import Image from './../nodes/Image.js'
 import Heading from './../nodes/Heading.js'
@@ -87,6 +88,7 @@ export default Extension.create({
 				inline: true,
 			}),
 			Dropcursor,
+			KeepSyntax,
 		]
 		if (this.options.link !== false) {
 			defaultExtensions.push(Link.configure({

src/extensions/index.js

@@ -28,6 +28,7 @@ import Collaboration from './Collaboration.js'
 import Markdown from './Markdown.js'
 import PlainText from './PlainText.js'
 import RichText from './RichText.js'
+import KeepSyntax from './KeepSyntax.js'
 
 export {
 	Emoji,
@@ -38,4 +39,5 @@ export {
 	Markdown,
 	PlainText,
 	RichText,
+	KeepSyntax,
 }

src/markdownit/index.js

@@ -3,6 +3,7 @@ import taskLists from '@hedgedoc/markdown-it-task-lists'
 import underline from './underline.js'
 import splitMixedLists from './splitMixedLists.js'
 import callouts from './callouts.js'
+import keepSyntax from './keepSyntax.js'
 
 const markdownit = MarkdownIt('commonmark', { html: false, breaks: false })
 	.enable('strikethrough')
@@ -11,5 +12,6 @@ const markdownit = MarkdownIt('commonmark', { html: false, breaks: false })
 	.use(splitMixedLists)
 	.use(underline)
 	.use(callouts)
+	.use(keepSyntax)
 
 export default markdownit

src/markdownit/keepSyntax.js

@@ -0,0 +1,59 @@
+/**
+ * @copyright Copyright (c) 2022
+ *
+ * @license AGPL-3.0-or-later
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * Add a mark for keeping special markdown syntax unescaped
+ *
+ * @param {object} md Markdown object
+ */
+export default function keepSyntax(md) {
+	const escaped = /((?<=\n)[#\-*+>]|[`*\\~[\]]+)/
+
+	md.core.ruler.before('text_join', 'tag-markdown-syntax', state => {
+		const open = new state.Token('keep_md_open', 'span', 1)
+		open.attrSet('class', 'keep-md')
+		const close = new state.Token('keep_md_close', 'span', -1)
+
+		for (let i = 0; i < state.tokens.length; i++) {
+			const block = state.tokens[i]
+			if (block.type !== 'inline') continue
+
+			for (let j = 0; j < block.children.length; j++) {
+				const token = block.children[j]
+				if (token.type === 'text') {
+					const match = escaped.exec(token.content)
+					if (match) {
+						const contentNext = match.index + match[0].length
+						block.children.splice(j, 1,
+							Object.assign({}, token, { content: token.content.slice(0, match.index) }),
+							Object.assign({}, open),
+							Object.assign({}, token, { content: token.content.slice(match.index, contentNext) }),
+							Object.assign({}, close),
+							Object.assign({}, token, { content: token.content.slice(contentNext) })
+						)
+						j += 3
+					}
+				}
+			}
+		}
+
+		return false
+	})
+}

src/tests/markdown.spec.js

@@ -45,7 +45,8 @@ describe('Commonmark', () => {
 			const expected = entry.markdown.includes('__')
 				? entry.html.replace(/<strong>/g, '<u>').replace(/<\/strong>/g, '</u>')
 				: entry.html
-			expect(markdownit.render(entry.markdown)).toBe(expected)
+			// Ignore special markup for untouched markdown
+			expect(markdownit.render(entry.markdown).replace(/<span class="keep-md">([^<]+)<\/span>/g, '$1')).toBe(expected)
 		})
 	})
 })
@@ -85,6 +86,8 @@ describe('Markdown though editor', () => {
 	test('links', () => {
 		expect(markdownThroughEditor('[test](foo)')).toBe('[test](foo)')
 		expect(markdownThroughEditor('[test](foo "bar")')).toBe('[test](foo "bar")')
+		// Issue #2703
+		expect(markdownThroughEditor('[bar\\\\]: /uri\n\n[bar\\\\]')).toBe('[bar\\\\](/uri)')
 	})
 	test('images', () => {
 		expect(markdownThroughEditor('![test](foo)')).toBe('![test](foo)')
@@ -95,6 +98,12 @@ describe('Markdown though editor', () => {
 	test('code block', () => {
 		expect(markdownThroughEditor('```\n<?php echo "Hello World";\n```')).toBe('```\n<?php echo "Hello World";\n```')
 	})
+	test('markdown untouched', () => {
+		// Issue #2703
+		expect(markdownThroughEditor('[bar\\\\]: /uri\n\n[bar\\\\]')).toBe('[bar\\\\](/uri)')
+		expect(markdownThroughEditor('## Test \\')).toBe('## Test \\')
+		expect(markdownThroughEditor('- [ [asd](sdf)')).toBe('* [ [asd](sdf)')
+	})
 	test('checkboxes', () => {
 		// Invalid ones but should be syntactical unchanged
 		expect(markdownThroughEditor('- [F] asd')).toBe('* [F] asd')