fix: Fix tab focus when other elements are displayed next to text tha…

…t are within a focus trap

Signed-off-by: Julius Härtl <jus@bitgrid.net>

src/EditorFactory.js

@@ -29,7 +29,7 @@ import { lowlight } from 'lowlight/lib/core.js'
 import hljs from 'highlight.js/lib/core'
 
 import { logger } from './helpers/logger.js'
-import { Mention, PlainText, RichText } from './extensions/index.js'
+import { FocusTrap, Mention, PlainText, RichText } from './extensions/index.js'
 // eslint-disable-next-line import/no-named-as-default
 import CodeBlockLowlight from '@tiptap/extension-code-block-lowlight'
 
@@ -64,6 +64,7 @@ const createEditor = ({ language, onCreate, onUpdate = () => {}, extensions, ena
 					}),
 				],
 			}),
+			FocusTrap,
 		]
 	} else {
 		defaultExtensions = [PlainText, CodeBlockLowlight.configure({ lowlight, defaultLanguage: language })]

src/components/Editor.vue

@@ -643,16 +643,10 @@ export default {
 
 		onFocus() {
 			this.emit('focus')
-
-			// Make sure that the focus trap doesn't catch tab keys while being in the contenteditable
-			window._nc_focus_trap?.[0]?.pause()
 		},
+
 		onBlur() {
 			this.emit('blur')
-
-			// Hand back focus to the previous trap
-			window._nc_focus_trap?.[0]?.unpause()
-			this.$el.focus()
 		},
 
 		onAddImageNode() {
@@ -750,6 +744,7 @@ export default {
 				this.$editor.commands.insertContent('\t')
 				this.$editor.commands.focus()
 				event.preventDefault()
+				event.stopPropagation()
 				return
 			}
 

src/components/Editor/ContentContainer.vue

@@ -30,8 +30,7 @@
 			<EditorOutline />
 		</div>
 		<slot />
-		<EditorContent tabindex="0"
-			role="document"
+		<EditorContent role="document"
 			class="editor__content text-editor__content"
 			:editor="$editor" />
 		<div class="text-editor__content-wrapper__right" />

src/extensions/FocusTrap.js

@@ -0,0 +1,41 @@
+import { Extension } from '@tiptap/core'
+
+const toggleFocusTrap = ({ editor }) => {
+	const trapStack = window._nc_focus_trap ?? []
+	const activeTrap = trapStack[trapStack.length - 1]
+
+	const possibleEditorTabCommand = editor.can().sinkListItem('listItem')
+		|| editor.can().goToNextCell()
+		|| editor.can().goToPreviousCell()
+
+	if (possibleEditorTabCommand) {
+		activeTrap?.pause()
+	} else {
+		activeTrap?.unpause()
+	}
+}
+
+const unpauseFocusTrap = ({ editor }) => {
+	const trapStack = window._nc_focus_trap ?? []
+	const activeTrap = trapStack[trapStack.length - 1]
+
+	activeTrap?.unpause()
+}
+
+/**
+ * The viewer focus trap needs to be paused on the fly in order to properly handle tab commands in the editor,
+ * as we have no control over if a tab key event is reaching the editor otherwise. This is because the focus trap
+ * registeres a capture listener (https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#capture), so whenever we reach a tab command in the editor the focus trap will already have captured the event.
+ *
+ * We also cannot work around this by pushing our own focus trap to the stack, as the focus trap package does not offer any reliable way to programmatically focus the next element of the parent trap if we allow tabbing out of the editor.
+ */
+const FocusTrap = Extension.create({
+	name: 'focustrap',
+	onFocus: toggleFocusTrap,
+	onBlur: unpauseFocusTrap,
+	onSelectionUpdate: toggleFocusTrap,
+	onTransaction: toggleFocusTrap,
+	onUpdate: toggleFocusTrap,
+})
+
+export default FocusTrap

src/extensions/index.js

@@ -22,6 +22,7 @@
 
 import CollaborationCursor from './CollaborationCursor.js'
 import Emoji from './Emoji.js'
+import FocusTrap from './FocusTrap.js'
 import Keymap from './Keymap.js'
 import UserColor from './UserColor.js'
 import Markdown from './Markdown.js'
@@ -33,6 +34,7 @@ import Mention from './Mention.js'
 export {
 	CollaborationCursor,
 	Emoji,
+	FocusTrap,
 	Keymap,
 	UserColor,
 	Markdown,

src/nodes/CodeBlockView.vue

@@ -46,7 +46,7 @@
 			</div>
 		</div>
 		<div :class="{'split-view': showCode && showPreview }">
-			<pre v-show="showCode" class="split-view__code"><NodeViewContent as="code" :contenteditable="isEditable" /></pre>
+			<pre v-show="showCode" class="split-view__code"><NodeViewContent as="code" tabindex="-1" :contenteditable="isEditable" /></pre>
 			<div v-show="showPreview"
 				ref="preview"
 				class="split-view__preview"