fix: handle unwrapping inline nodes in lists

Author: demshy

packages/decap-cms-widget-markdown/src/MarkdownControl/plugins/blocks/transforms/unwrapIfCursorAtStart.js

@@ -5,18 +5,28 @@ import lowestMatchedAncestor from '../../matchers/lowestMatchedAncestor';
 function unwrapIfCursorAtStart(editor, mergeWithPrevious = false) {
   if (editor.selection.anchor.offset !== 0) return false;
 
-  const node = Editor.above(editor, lowestMatchedAncestor(editor, 'non-default'));
+  let [node, path] = Editor.above(editor, lowestMatchedAncestor(editor, 'non-default'));
 
-  if (node[1].length == 0) return false;
+  if (path.length == 0) return false;
 
-  const isHeading = `${node[0].type}`.startsWith('heading-');
+  const isHeading = `${node.type}`.startsWith('heading-');
   if (isHeading) {
     Transforms.setNodes(editor, { type: 'paragraph' });
     return false;
   }
 
+  const isBlock = Editor.isBlock(editor, node);
+  const [parentBlock, parentBlockPath] = Editor.above(editor, lowestMatchedAncestor(editor, 'block'));
+  if (!isBlock) {
+    if (!Editor.isStart(editor, path, parentBlockPath)) {
+      return false;
+    }
+
+    [node, path] = [parentBlock, parentBlockPath];
+  }
+
   Editor.withoutNormalizing(editor, () => {
-    Transforms.unwrapNodes(editor, { match: n => n.type === node[0].type, split: true });
+    Transforms.unwrapNodes(editor, { match: n => n.type === node.type, split: true });
 
     if (mergeWithPrevious) {
       Transforms.mergeNodes(editor);