fix: copy-paste markdown/raw text inconsistencies (#5487)

* fix: traverse through nodes in order to determine the correct copy-paste behavior

---------

Signed-off-by: Elizabeth Danzberger <lizzy7128@tutanota.de>
Signed-off-by: Max <max@nextcloud.com>
Co-authored-by: Max <max@nextcloud.com>

Author: elzody

src/extensions/Markdown.js

@@ -108,7 +108,17 @@ const Markdown = Extension.create({
 						return parser.parseSlice(dom, { preserveWhitespace: true, context: $context })
 					},
 					clipboardTextSerializer: (slice) => {
-						return createMarkdownSerializer(this.editor.schema).serialize(slice.content)
+						const traverseNodes = (slice) => {
+							if (slice.content.childCount > 1) {
+								return createMarkdownSerializer(this.editor.schema).serialize(slice.content)
+							} else if (slice.isLeaf) {
+								return slice.textContent
+							} else {
+								return traverseNodes(slice.content.firstChild)
+							}
+						}
+
+						return traverseNodes(slice)
 					},
 					transformPastedHTML,
 				},

src/tests/extensions/Markdown.spec.js

@@ -1,12 +1,15 @@
 import { Markdown } from './../../extensions/index.js'
 import { createMarkdownSerializer } from './../../extensions/Markdown.js'
+import CodeBlock from '@tiptap/extension-code-block'
+import Blockquote from '@tiptap/extension-blockquote'
 import Image from './../../nodes/Image.js'
 import ImageInline from './../../nodes/ImageInline.js'
 import TaskList from './../../nodes/TaskList.js'
 import TaskItem from './../../nodes/TaskItem.js'
 import Underline from './../../marks/Underline.js'
 import TiptapImage from '@tiptap/extension-image'
 import { getExtensionField } from '@tiptap/core'
+import { __serializeForClipboard as serializeForClipboard } from '@tiptap/pm/view'
 import { createCustomEditor } from '../helpers.js'
 
 describe('Markdown extension unit', () => {
@@ -77,4 +80,37 @@ describe('Markdown extension integrated in the editor', () => {
 		expect(serializer.serialize(editor.state.doc)).toBe('inline image ![Hello](test) inside text')
 	})
 
+	it('copies task lists to plaintext like markdown', () => {
+		const editor = createCustomEditor({
+			content: '<p><ul class="contains-task-list"><li><input type="checkbox">Hello</li></ul></p>',
+			extensions: [Markdown, TaskList, TaskItem],
+		})
+		editor.commands.selectAll()
+		const slice = editor.state.selection.content()
+		const { text } = serializeForClipboard(editor.view, slice)
+		expect(text).toBe('\n- [ ] Hello')
+	})
+
+	it('copies code block content to plaintext according to their spec', () => {
+		const editor = createCustomEditor({
+			content: '<pre><code>Hello</code></pre>',
+			extensions: [Markdown, CodeBlock],
+		})
+		editor.commands.selectAll()
+		const slice = editor.state.selection.content()
+		const { text } = serializeForClipboard(editor.view, slice)
+		expect(text).toBe('Hello')
+	})
+
+	it('copies nested task list nodes to markdown like syntax', () => {
+		const editor = createCustomEditor({
+			content: '<blockquote><p><ul class="contains-task-list"><li><input type="checkbox">Hello</li></ul></blockquote>',
+			extensions: [Markdown, Blockquote, TaskList, TaskItem],
+		})
+		editor.commands.selectAll()
+		const slice = editor.state.selection.content()
+		const { text } = serializeForClipboard(editor.view, slice)
+		expect(text).toBe('\n- [ ] Hello')
+	})
+
 })