Add getPromiseState microtask timing tests

[NullVoxPopuli]

Adds tests that read getPromiseState from JS, with no render() or settled(), and record which microtask each property changes on. No behavior changes.

Results

input	sync	resolved / error set	isLoading → false
plain value, sync function, sync throw, settled cache hit	settled	sync	sync
Promise.resolve, async () => value	loading	microtask 1	microtask 3
Promise.reject	loading	microtask 2	microtask 3
async fn with one await	loading	microtask 2	microtask 4
async fn that awaits, then throws	loading	microtask 3	microtask 4

Nothing changes after a macrotask.

Worth noting: for promises, there's a window of 1–2 microtasks where resolved (or error) is set but isLoading is still true. This happens because the state is updated in a .then().catch().finally() chain, one link per microtask. Templates never show it because they wait for the render loop. JS code that checks isLoading first could see it. These tests pin it down so any fix is deliberate.

How it works: a stepTimeline(state, assert) helper reads the state right after the call, after each of 10 await Promise.resolve()s, and after a setTimeout. Each time the state changes, it calls assert.step, and the test checks the result with assert.verifySteps.

🤖 Generated with Claude Code

[vercel]

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Project	Deployment	Actions	Updated
reactive	Ready	Preview	Oct 14, 2026 6:05pm UTC