test(web): свод 2 — окно строк через отступы виртуализатора

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/pages/Svod2Page/svod2Virtualizer.test.js

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+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { Virtualizer } from '@tanstack/virtual-core';
+
+test('paddingStart/paddingEnd ставят глобальную строку i на i*rowH, общий размер = total*rowH', () => {
+	const rowH = 37;
+	const total = 5563;
+	const windowStart = 300;
+	const windowEnd = 1200;
+	const v = new Virtualizer({
+		count: windowEnd - windowStart,
+		getScrollElement: () => null,
+		estimateSize: () => rowH,
+		paddingStart: windowStart * rowH,
+		paddingEnd: (total - windowEnd) * rowH,
+		scrollToFn: () => undefined,
+		observeElementRect: () => undefined,
+		observeElementOffset: () => undefined,
+	});
+	const m = v.getMeasurements();
+	assert.equal(m[0].start, windowStart * rowH);
+	assert.equal(m.at(-1).end, windowEnd * rowH);
+	assert.equal(v.getTotalSize(), total * rowH);
+});