retain empty text objects in some cases - fixes #108

yjs · May 13, 2022 · a20c9d8 · a20c9d8
1 parent f2f8365
commit a20c9d8
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Showing 2 changed files with 18 additions and 1 deletion.
diff --git a/src/plugins/sync-plugin.js b/src/plugins/sync-plugin.js
@@ -826,7 +826,11 @@ export const updateYFragment = (y, yDomFragment, pNode, mapping) => {
       }
     }
     const yDelLen = yChildCnt - left - right
-    if (yDelLen > 0) {
+    if (yChildCnt === 1 && pChildCnt === 0 && yChildren[0] instanceof Y.XmlText) {
+      // Edge case handling https://github.com/yjs/y-prosemirror/issues/108
+      // Only delete the content of the Y.Text to retain remote changes on the same Y.Text object
+      yChildren[0].delete(0, yChildren[0].length)
+    } else if (yDelLen > 0) {
       yDomFragment.delete(left, yDelLen)
     }
     if (left + right < pChildCnt) {

diff --git a/test/y-prosemirror.test.js b/test/y-prosemirror.test.js
@@ -59,6 +59,19 @@ export const testEmptyNotSync = tc => {
   t.compareStrings(type.toString(), '<custom checked="true"></custom><paragraph></paragraph>')
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+export const testEmptyParagraph = tc => {
+  const ydoc = new Y.Doc()
+  const view = createNewProsemirrorView(ydoc)
+  view.dispatch(view.state.tr.insert(0, /** @type {any} */ (schema.node('paragraph', undefined, schema.text('123')))))
+  const yxml = ydoc.get('prosemirror')
+  t.assert(yxml.length === 2 && yxml.get(0).length === 1, 'contains one paragraph containing a ytext')
+  view.dispatch(view.state.tr.delete(1, 4)) // delete characters 123
+  t.assert(yxml.length === 2 && yxml.get(0).length === 1, 'doesn\'t delete the ytext')
+}
+
 const createNewComplexProsemirrorView = y => {
   const view = new EditorView(null, {
     // @ts-ignore