An older navigation can overwrite the URL after a newer navigation commits #507

Description

An earlier navigation can commit its URL after a later navigation has already rendered and committed. This leaves the displayed page and browser URL pointing to different destinations.

Unlike #506, this occurs with default navigation options, without preserveState: true.

Environment

• Commit: 2ceab89154dc6e0c3fa5525f7bd4d1d5f3d0aa64
• Package version: 1.1.12
• OS: Ubuntu 24.04.3 LTS x86_64
• Node: 24.21.0
• Vite+: 1.3.0; Vitest: 5.0.5
• Playwright: 1.64.1
• Chromium Headless Shell: 134.0.6998.35

Steps to reproduce

1. Initialize the production createVoidRouter() in a browser fixture with valid Pages responses for /a and /b, with View Transitions disabled.
2. Provide an adapter whose applyUpdate() updates the displayed page but returns a controllable Promise for /a:

let releaseA!: () => void;
let enteredA!: () => void;

const gate = new Promise<void>(resolve => {
  releaseA = resolve;
});
const entered = new Promise<void>(resolve => {
  enteredA = resolve;
});

const adapter = {
  // Other adapter methods omitted.
  applyUpdate(pageData: { url: string }) {
    document.getElementById('app')!.textContent = pageData.url;

    if (pageData.url === '/a') {
      enteredA();
      return gate;
    }
  },
};

3. Start navigation A, allow B to finish, and then release A:

const visitA = router.visit('/a');
await entered;

await router.visit('/b');

releaseA();
await visitA;

4. Compare the displayed page with window.location.pathname.

Actual behavior

The older navigation overwrites the URL after the newer navigation has committed:

A newly added Playwright integration test reproduced this in both runs. The normal-navigation control passed in both runs.

The test was executed through the repository's parallel-integration project:

vp test run packages/void/test/integration/pages-navigation-race.test.ts --project parallel-integration

The fixture serves the production Pages client through a local HTTP server and controls the adapter's update timing. This verifies the Core/browser race; it is not a full production-build test across every framework adapter.

Expected behavior

The displayed page and browser URL should both remain /b.

Once B has superseded A and committed, completing A's pending adapter update should not allow A to commit its URL or other navigation side effects.

Relevant implementation

In packages/void/src/pages/navigation-engine.ts, makeCommit() uses the pending resource ID when clearing pending state, but that check does not guard the remaining commit operations.

applyNavigationResource() in packages/void/src/pages/client.ts awaits the adapter update and then calls resource.commit(). Consequently, the older resource can still reach the history-writing path after the newer resource has committed.

Acceptance criteria

• A superseded navigation cannot overwrite the URL after a newer navigation commits.
• The reproduction above leaves both the displayed page and URL at /b.
• A superseded commit does not overwrite the newer page's head, scroll, or Deferred resource ownership.
• Regression coverage includes controlled adapter-update completion orders and a normal-navigation control.