fix: panic when detach then attach (#592)

detaching should commit the pending ops

.changeset/rotten-penguins-relate.md

@@ -0,0 +1,5 @@
+---
+"loro-crdt": patch
+---
+
+Fix detach + attach error

crates/loro-internal/src/loro.rs

@@ -282,6 +282,7 @@ impl LoroDoc {
 
     #[inline(always)]
     pub fn detach(&self) {
+        self.commit_then_stop();
         self.set_detached(true);
     }
 

crates/loro-wasm/tests/basic.test.ts

@@ -984,3 +984,12 @@ it("can use version vector multiple times", () => {
   doc.vvToFrontiers(v);
   v.toJSON();
 })
+
+it("detach and attach on empty doc", () => {
+  const doc = new LoroDoc();
+  expect(doc.isDetached()).toBe(false);
+  doc.detach();
+  expect(doc.isDetached()).toBe(true);
+  doc.attach();
+  expect(doc.isDetached()).toBe(false);
+})

crates/loro/tests/loro_rust_test.rs

@@ -2339,3 +2339,13 @@ fn test_get_or_create_container_with_null() {
         json!({ "root": { "key": {} } })
     );
 }
+
+#[test]
+fn test_detach_and_attach() {
+    let doc = LoroDoc::new();
+    assert!(!doc.is_detached());
+    doc.detach();
+    assert!(doc.is_detached());
+    doc.attach();
+    assert!(!doc.is_detached());
+}