Prevent Android chats from freezing or going blank (#1989)

* fix(app): stabilize streamed chat rendering Use deterministic Markdown AST keys and preserve unique row identities when an assistant message resumes after a tool. Keep native gesture and plan-card children correctly keyed to avoid unsupported Fabric reconciliation paths. * fix(app): stabilize retained native panels Keep retained workspace roots in a stable native order and make active panels present in the selection commit. Hidden panels now stop expensive subscriptions and animations without losing mounted state. * fix(app): harden retained panel activity
2026-07-11 15:39:14 +08:00
parent 860fcb2e35
commit 28a27b02d3
40 changed files with 1244 additions and 543 deletions
@@ -37,6 +37,91 @@ test.describe("Agent stream UI", () => {
    }
  });

+  test("keeps the active Markdown root mounted across streamed text updates", async ({
+    page,
+  }, testInfo) => {
+    test.setTimeout(120_000);
+    const agent = await startRunningMockAgent(page, {
+      prefix: "stream-markdown-root-",
+      model: "one-minute-stream",
+      prompt: "Stream for Markdown root stability test.",
+    });
+    try {
+      const assistantMessage = page.getByTestId("assistant-message").last();
+      await expect(assistantMessage).toContainText("walking through", { timeout: 30_000 });
+
+      const activeBlock = assistantMessage.locator(":scope > *").last();
+      const initialText = (await activeBlock.textContent()) ?? "";
+      const activeBlockHandle = await activeBlock.elementHandle();
+      if (!activeBlockHandle) {
+        throw new Error("Expected the active assistant message to contain a block");
+      }
+      const markdownRoot = await activeBlock.locator(":scope > *").first().elementHandle();
+      if (!markdownRoot) {
+        throw new Error("Expected the active assistant block to contain a Markdown root");
+      }
+
+      await page.evaluate((block) => {
+        const evidence = {
+          addedNodes: 0,
+          characterDataMutations: 0,
+          removedNodes: 0,
+        };
+        const observer = new MutationObserver((records) => {
+          for (const record of records) {
+            evidence.addedNodes += record.addedNodes.length;
+            evidence.removedNodes += record.removedNodes.length;
+            if (record.type === "characterData") {
+              evidence.characterDataMutations += 1;
+            }
+          }
+        });
+        observer.observe(block, { characterData: true, childList: true, subtree: true });
+        Object.assign(window, {
+          __markdownRootEvidence: evidence,
+          __markdownRootObserver: observer,
+        });
+      }, activeBlockHandle);
+
+      await expect
+        .poll(async () => ((await activeBlock.textContent()) ?? "").length)
+        .toBeGreaterThan(initialText.length + 80);
+
+      const evidence = await page.evaluate((root) => {
+        const state = window as typeof window & {
+          __markdownRootEvidence?: {
+            addedNodes: number;
+            characterDataMutations: number;
+            removedNodes: number;
+          };
+          __markdownRootObserver?: MutationObserver;
+        };
+        state.__markdownRootObserver?.disconnect();
+        const messages = document.querySelectorAll('[data-testid="assistant-message"]');
+        const message = messages.item(messages.length - 1);
+        const block = message?.lastElementChild;
+        return {
+          ...state.__markdownRootEvidence,
+          connected: root.isConnected,
+          sameRoot: block?.firstElementChild === root,
+        };
+      }, markdownRoot);
+
+      await testInfo.attach("markdown-root-stability", {
+        body: JSON.stringify(evidence, null, 2),
+        contentType: "application/json",
+      });
+      expect(evidence.connected).toBe(true);
+      expect(evidence.sameRoot).toBe(true);
+      expect(
+        evidence.removedNodes,
+        `Streaming Markdown replaced mounted descendants: ${JSON.stringify(evidence)}`,
+      ).toBe(0);
+    } finally {
+      await agent.cleanup();
+    }
+  });
+
  test("keeps the viewport fixed after the user scrolls away during a stream", async ({ page }) => {
    test.setTimeout(120_000);
    const agent = await seedMockAgentWorkspace({