test(performance): bound worker sampling finalization (#1302)

* test(performance): bound worker sampling finalization

* test(performance): reject timed-out worker captures

* test(performance): settle every worker sample

apps/electron-backend-e2e/src/performance/worker-sample-capture-validity.spec.ts

@@ -0,0 +1,73 @@
+/* eslint-disable playwright/expect-expect -- This is a Node assertion-based performance contract test. */
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import test from 'node:test';
+
+interface WorkerSampleDeadlineModule {
+    assertWorkerSampleCaptureValid?: (
+        invalidReasons: readonly string[]
+    ) => void;
+}
+
+const modulePromise = import(
+    new URL('./worker-sample-deadline.ts', import.meta.url).href
+).then((module) => module as WorkerSampleDeadlineModule);
+
+test('rejects a timed-out worker sample before returning plain capture metrics', async () => {
+    const module = await modulePromise;
+    const assertCaptureValid = module.assertWorkerSampleCaptureValid;
+    assert.equal(typeof assertCaptureValid, 'function');
+
+    assert.doesNotThrow(() => assertCaptureValid?.([]));
+    assert.throws(
+        () => assertCaptureValid?.(['worker-sample-timeout']),
+        /main-capture-worker-sample-timeout/
+    );
+});
+
+test('plain capture stop and rollover both enforce worker sample validity', () => {
+    const source = readFileSync(
+        new URL('./m3u-refresh-main-capture.ts', import.meta.url),
+        'utf8'
+    );
+    const rolloverStart = source.indexOf(
+        'export async function rolloverMainCapture'
+    );
+    const stopStart = source.indexOf('export async function stopMainCapture');
+    const xtreamRolloverStart = source.indexOf(
+        'export async function rolloverXtreamMainCapture'
+    );
+    const rollover = source.slice(rolloverStart, stopStart);
+    const stop = source.slice(stopStart, xtreamRolloverStart);
+
+    assert.match(
+        rollover,
+        /assertWorkerSampleCaptureValid\(transport\.xtream\.invalidReasons\)/
+    );
+    assert.match(
+        stop,
+        /assertWorkerSampleCaptureValid\(transport\.xtream\.invalidReasons\)/
+    );
+});
+
+test('capture stop settles final samples for every current worker', () => {
+    const source = readFileSync(
+        new URL('./m3u-refresh-main-capture.ts', import.meta.url),
+        'utf8'
+    );
+    const stopStart = source.indexOf('stop: async (');
+    const stopEnd = source.indexOf(
+        'xtreamStatus: (): XtreamMainCaptureStatus',
+        stopStart
+    );
+    const stop = source.slice(stopStart, stopEnd);
+
+    assert.match(
+        stop,
+        /await Promise\.all\(\s*currentWorkerRecords\.map\(\(record\) =>\s*joinFinalWorkerSample\(record\)/
+    );
+    assert.doesNotMatch(
+        stop,
+        /currentDatabaseRecords\.map\(\(record\) =>\s*joinFinalWorkerSample\(record\)/
+    );
+});