1 files changed, 33 insertions, 1 deletions
diff --git a/app/assets/javascripts/content_editor/extensions/blockquote.js b/app/assets/javascripts/content_editor/extensions/blockquote.js
index 45f53fe230b..4512ead44bc 100644
--- a/app/assets/javascripts/content_editor/extensions/blockquote.js
+++ b/app/assets/javascripts/content_editor/extensions/blockquote.js
@@ -1 +1,33 @@
-export { Blockquote as default } from '@tiptap/extension-blockquote';
+import { Blockquote } from '@tiptap/extension-blockquote';
+import { wrappingInputRule } from 'prosemirror-inputrules';
+import { getParents } from '~/lib/utils/dom_utils';
+import { getMarkdownSource } from '../services/markdown_sourcemap';
+
+export const multilineInputRegex = /^\s*>>>\s$/gm;
+
+export default Blockquote.extend({
+  addAttributes() {
+    return {
+      ...this.parent?.(),
+
+      multiline: {
+        default: false,
+        parseHTML: (element) => {
+          const source = getMarkdownSource(element);
+          const parentsIncludeBlockquote = getParents(element).some(
+            (p) => p.nodeName.toLowerCase() === 'blockquote',
+          );
+
+          return source && !source.startsWith('>') && !parentsIncludeBlockquote;
+        },
+      },
+    };
+  },
+
+  addInputRules() {
+    return [
+      ...this.parent?.(),
+      wrappingInputRule(multilineInputRegex, this.type, () => ({ multiline: true })),
+    ];
+  },
+});