Commit LLM generated test cases

frontend/deterministic-tests/src/tests/concurrent-rename-and-create-at-target.test.ts

@@ -0,0 +1,90 @@
+import type { ClientState, TestDefinition } from "../test-definition";
+import { assert } from "../utils/assert";
+
+/**
+ * EDGE CASE: Client A renames X→Y while Client B creates at Y.
+ *
+ * This tests a tricky scenario where:
+ * 1. Both clients know about X.md
+ * 2. Client A renames X→Y (offline)
+ * 3. Client B creates a NEW file at Y (offline)
+ * 4. Both reconnect
+ *
+ * The server should handle this by:
+ * - Client A's rename succeeds (X→Y)
+ * - Client B's create at Y triggers a smart merge with A's renamed document
+ * - Both documents' content should be preserved
+ */
+function verifyFinalState(state: ClientState): void {
+    // X should not exist (renamed by A)
+    assert(
+        !state.files.has("X.md"),
+        `X.md should not exist, files: ${Array.from(state.files.keys()).join(", ")}`
+    );
+
+    // Y should exist with merged content
+    assert(
+        state.files.has("Y.md"),
+        `Y.md should exist, files: ${Array.from(state.files.keys()).join(", ")}`
+    );
+
+    const content = state.files.get("Y.md") ?? "";
+    // Both pieces of content should be preserved through merge
+    assert(
+        content.includes("original file X"),
+        `Expected content to include "original file X", got: "${content}"`
+    );
+    assert(
+        content.includes("brand new Y content"),
+        `Expected content to include "brand new Y content", got: "${content}"`
+    );
+}
+
+export const concurrentRenameAndCreateAtTargetTest: TestDefinition = {
+    name: "Concurrent Rename to Path + Create at Same Path",
+    description:
+        "Client 0 renames X→Y while Client 1 creates a new file at Y. " +
+        "Both operations happen offline. On reconnect, the server should " +
+        "merge the renamed document with the created document.",
+    clients: 2,
+    steps: [
+        // Setup: create X.md on Client 0
+        {
+            type: "create",
+            client: 0,
+            path: "X.md",
+            content: "original file X"
+        },
+        { type: "enable-sync", client: 0 },
+        { type: "enable-sync", client: 1 },
+        { type: "sync" },
+        { type: "barrier" },
+
+        // Both go offline
+        { type: "disable-sync", client: 0 },
+        { type: "disable-sync", client: 1 },
+
+        // Client 0: rename X→Y
+        { type: "rename", client: 0, oldPath: "X.md", newPath: "Y.md" },
+
+        // Client 1: create Y with different content
+        // (Client 1 still has X.md locally)
+        {
+            type: "create",
+            client: 1,
+            path: "Y.md",
+            content: "brand new Y content"
+        },
+
+        // Client 0 reconnects first (rename goes through)
+        { type: "enable-sync", client: 0 },
+        { type: "sync", client: 0 },
+
+        // Client 1 reconnects (create at Y triggers smart merge)
+        { type: "enable-sync", client: 1 },
+        { type: "sync" },
+        { type: "barrier" },
+
+        { type: "assert-consistent", verify: verifyFinalState }
+    ]
+};