front_end/models/trace/insights/ForcedReflow.test.ts

// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import {describeWithEnvironment} from '../../../testing/EnvironmentHelpers.js';
import {getInsightOrError} from '../../../testing/InsightHelpers.js';
import {TraceLoader} from '../../../testing/TraceLoader.js';

describeWithEnvironment('ForcedReflow', function() {
  async function processTrace(context: Mocha.Suite|Mocha.Context, traceFile: string) {
    const {data, insights} = await TraceLoader.traceEngine(context, traceFile);
    if (!insights) {
      throw new Error('No insights');
    }

    return {data, insights};
  }

  it('generates call stacks', async function() {
    const {data, insights} = await processTrace(this, 'forced-reflow.json.gz');
    assert.strictEqual(insights.size, 1);
    const insight =
        getInsightOrError('ForcedReflow', insights, data.Meta.navigationsByNavigationId.values().next().value);

    assert.strictEqual(insight.topLevelFunctionCallData?.topLevelFunctionCall.columnNumber, 25217);
    assert.strictEqual(insight.topLevelFunctionCallData?.topLevelFunctionCall.lineNumber, 6);
    assert.strictEqual(insight.topLevelFunctionCallData?.totalReflowTime, 26052);

    const callStack = insight.aggregatedBottomUpData[1];
    assert.strictEqual(callStack.bottomUpData!.columnNumber, 197203);
    assert.strictEqual(callStack.bottomUpData!.lineNumber, 32);
    assert.lengthOf(callStack.relatedEvents, 16);
  });
});