From d26bd9a2155977e3ff020bdd5c1bb862a4c1210f Mon Sep 17 00:00:00 2001
From: David Brochart <david.brochart@gmail.com>
Date: Thu, 30 May 2024 10:13:00 +0200
Subject: [PATCH] Add undo manager test (#48)

---
 tests/test_pycrdt_yjs.py | 15 +++++++++++++++
 tests/yjs_client_2.js    | 29 +++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)
 create mode 100644 tests/yjs_client_2.js

diff --git a/tests/test_pycrdt_yjs.py b/tests/test_pycrdt_yjs.py
index fe0fca2..a1bb72c 100644
--- a/tests/test_pycrdt_yjs.py
+++ b/tests/test_pycrdt_yjs.py
@@ -58,3 +58,18 @@ async def test_pycrdt_yjs_1(yws_server, yws_provider, yjs_client):
     await ystate_change.wait()
     assert ycells.to_py() == [{"metadata": {"foo": "bar"}, "source": "1 + 2"}]
     assert ystate.to_py() == {"state": {"dirty": False}}
+
+
+@pytest.mark.parametrize("yjs_client", [2], indirect=True)
+async def test_pycrdt_yjs_2(yws_server, yws_provider, yjs_client):
+    ydoc, _ = yws_provider
+    ydoc["map0"] = map0 = Map()
+    map0_change = watch(map0)
+    await map0_change.wait()
+    assert map0.get("key0") == "val0"
+    # client is synced, let's make a change
+    map0["key1"] = "val1"
+    # wait for client to undo the change
+    map0_change = watch(map0)
+    await map0_change.wait()
+    assert "key1" not in map0
diff --git a/tests/yjs_client_2.js b/tests/yjs_client_2.js
new file mode 100644
index 0000000..54a0fbc
--- /dev/null
+++ b/tests/yjs_client_2.js
@@ -0,0 +1,29 @@
+const Y = require('yjs')
+const WebsocketProvider = require('y-websocket').WebsocketProvider
+const ws = require('ws')
+
+const port = process.argv[2]
+const ydoc = new Y.Doc()
+
+const wsProvider = new WebsocketProvider(
+  `ws://127.0.0.1:${port}`, 'my-roomname',
+  ydoc,
+  { WebSocketPolyfill: ws }
+)
+
+wsProvider.on('sync', () => {
+  const map0 = ydoc.getMap('map0')
+  const undoManager = new Y.UndoManager(map0, {
+    trackedOrigins: new Set([wsProvider]),
+  })
+  map0.set('key0', 'val0')
+  undoManager.clear()
+
+  function undo() {
+    undoManager.undo()
+  }
+
+  map0.observe((event, transaction) => {
+    setTimeout(undo, 100)
+  })
+})