test: alternate screen teardown-safety and debug-mode tests

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/runtime-tests/integration/lifecycle/alternate-screen.test.tsx

@@ -1,7 +1,8 @@
-import { defineComponent, nextTick } from "vue";
+import { defineComponent, nextTick, onScopeDispose } from "vue";
 import { expect, test } from "vite-plus/test";
 import { createApp, Text } from "@vue-tui/runtime";
 import ansiEscapes from "ansi-escapes";
+import stripAnsi from "strip-ansi";
 import { PassThrough } from "node:stream";
 
 function makeTtyStream(options?: { isTTY?: boolean }) {
@@ -232,3 +233,134 @@ test("alternate screen - cursor restored after exit", async () => {
   expect(exitIndex).not.toBe(-1);
   expect(showCursorIndex).toBeGreaterThan(exitIndex);
 });
+
+test("alternate screen - does not replay exit(Error) output on primary screen", async () => {
+  const stdout = makeTtyStream();
+  const stdin = makeFakeStdin();
+
+  const ErrorApp = defineComponent(() => {
+    throw new Error("Done");
+  });
+
+  const app = createApp(ErrorApp);
+  app.mount({
+    stdout,
+    stdin,
+    stderr: makeTtyStream(),
+    alternateScreen: true,
+    interactive: true,
+    exitOnCtrlC: false,
+  });
+  const exited = app.waitUntilExit();
+  await nextTick();
+  await nextTick();
+  await new Promise<void>((r) => setImmediate(r));
+  await nextTick();
+
+  await expect(exited).rejects.toThrow("Done");
+
+  const chunks = stdout.chunks;
+  const exitIndex = chunks.findLastIndex((w) => w.includes(ansiEscapes.exitAlternativeScreen));
+  expect(exitIndex).not.toBe(-1);
+
+  // After exiting the alternate screen, no error content should leak
+  // to the primary screen (no stack trace, no "Error: Done" text).
+  const afterExit = stripAnsi(chunks.slice(exitIndex + 1).join(""));
+  expect(afterExit).not.toContain("Error: Done");
+  expect(afterExit).not.toContain("Done\n    at");
+});
+
+test("alternate screen - does not replay teardown output on primary screen", async () => {
+  const stdout = makeTtyStream();
+  const stdin = makeFakeStdin();
+
+  const TeardownApp = defineComponent(() => () => <Text>fullscreen content</Text>);
+
+  const app = createApp(TeardownApp);
+  app.mount({
+    stdout,
+    stdin,
+    stderr: makeTtyStream(),
+    alternateScreen: true,
+    interactive: true,
+    exitOnCtrlC: false,
+  });
+  await nextTick();
+
+  const preUnmount = stdout.chunks.join("");
+  expect(preUnmount).toContain("fullscreen content");
+
+  const exited = app.waitUntilExit();
+  app.unmount();
+  await exited;
+
+  const chunks = stdout.chunks;
+  const exitIndex = chunks.findLastIndex((w) => w.includes(ansiEscapes.exitAlternativeScreen));
+  expect(exitIndex).not.toBe(-1);
+
+  const afterExit = stripAnsi(chunks.slice(exitIndex + 1).join(""));
+  expect(afterExit).not.toContain("fullscreen content");
+});
+
+test("alternate screen - cleanup console output does not leak into managed stream", async () => {
+  const stdout = makeTtyStream();
+  const stdin = makeFakeStdin();
+
+  let disposed = false;
+  const CleanupApp = defineComponent(() => {
+    onScopeDispose(() => {
+      disposed = true;
+      console.log("cleanup log");
+    });
+    return () => <Text>Hello</Text>;
+  });
+
+  const app = createApp(CleanupApp);
+  app.mount({
+    stdout,
+    stdin,
+    stderr: makeTtyStream(),
+    alternateScreen: true,
+    interactive: true,
+    exitOnCtrlC: false,
+    patchConsole: true,
+  });
+  await nextTick();
+
+  const exited = app.waitUntilExit();
+  app.unmount();
+  await exited;
+
+  expect(disposed).toBe(true);
+
+  const output = stdout.chunks.join("");
+  expect(output).not.toContain("cleanup log");
+});
+
+test("alternate screen - still activates in debug mode", async () => {
+  const stdout = makeTtyStream();
+  const stdin = makeFakeStdin();
+
+  const app = createApp(App);
+  app.mount({
+    stdout,
+    stdin,
+    stderr: makeTtyStream(),
+    alternateScreen: true,
+    interactive: true,
+    debug: true,
+    exitOnCtrlC: false,
+  });
+  await nextTick();
+
+  const exited = app.waitUntilExit();
+  app.unmount();
+  await exited;
+
+  const chunks = stdout.chunks;
+  const enterIndex = chunks.findIndex((w) => w.includes(ansiEscapes.enterAlternativeScreen));
+  const exitIndex = chunks.findLastIndex((w) => w.includes(ansiEscapes.exitAlternativeScreen));
+
+  expect(enterIndex).not.toBe(-1);
+  expect(exitIndex).not.toBe(-1);
+});