/**
* @license
* Copyright 2017 Google Inc.
* SPDX-License-Identifier: Apache-2.0
*/
import fs from 'fs' ;
import path from 'path' ;
import expect from 'expect' ;
import * as utils from 'puppeteer-core/internal/common/util.js' ;
import sinon from 'sinon' ;
import {launch} from './mocha-utils.js' ;
describe('Tracing' , function () {
let outputFile!: string;
let testState: Awaited<ReturnType<typeof launch>>;
/* we manually manage the browser here as we want a new browser for each
* individual test, which isn't the default behaviour of getTestState()
*/
beforeEach(async () => {
testState = await launch({}, {createContext: true });
outputFile = path.join(__dirname, 'trace.json' );
});
afterEach(async () => {
await testState.close();
if (fs.existsSync(outputFile)) {
fs.unlinkSync(outputFile);
}
});
it('should output a trace' , async () => {
const {server, page} = testState;
await page.tracing.start({screenshots: true , path: outputFile});
await page.goto (server.PREFIX + '/grid.html' );
await page.tracing.stop();
expect(fs.existsSync(outputFile)).toBe(true );
});
it('should run with custom categories if provided' , async () => {
const {page} = testState;
await page.tracing.start({
path: outputFile,
categories: ['-*' , 'disabled-by-default-devtools.timeline.frame' ],
});
await page.tracing.stop();
const traceJson = JSON.parse(
fs.readFileSync(outputFile, {encoding: 'utf8' }),
);
const traceConfig = JSON.parse(traceJson.metadata['trace-config' ]);
expect(traceConfig.included_categories).toEqual([
'disabled-by-default-devtools.timeline.frame' ,
]);
expect(traceConfig.excluded_categories).toEqual(['*' ]);
expect(traceJson.traceEvents).not.toContainEqual(
expect.objectContaining({
cat: 'toplevel' ,
}),
);
});
it('should run with default categories' , async () => {
const {page} = testState;
await page.tracing.start({
path: outputFile,
});
await page.tracing.stop();
const traceJson = JSON.parse(
fs.readFileSync(outputFile, {encoding: 'utf8' }),
);
expect(traceJson.traceEvents).toContainEqual(
expect.objectContaining({
cat: 'toplevel' ,
}),
);
});
it('should throw if tracing on two pages' , async () => {
const {page, browser} = testState;
await page.tracing.start({path: outputFile});
const newPage = await browser.newPage();
let error!: Error;
await newPage.tracing.start({path: outputFile}).catch (error_ => {
return (error = error_);
});
await newPage.close();
expect(error).toBeTruthy();
await page.tracing.stop();
});
it('should return a typedArray' , async () => {
const {page, server} = testState;
await page.tracing.start({screenshots: true , path: outputFile});
await page.goto (server.PREFIX + '/grid.html' );
const trace = (await page.tracing.stop())!;
const buf = fs.readFileSync(outputFile);
expect(trace).toBeInstanceOf(Uint8Array);
expect(Buffer.from(trace).toString()).toEqual(buf.toString());
});
it('should work without options' , async () => {
const {page, server} = testState;
await page.tracing.start();
await page.goto (server.PREFIX + '/grid.html' );
const trace = await page.tracing.stop();
expect(trace).toBeTruthy();
});
it('should return undefined in case of Buffer error' , async () => {
const {page, server} = testState;
await page.tracing.start({screenshots: true });
await page.goto (server.PREFIX + '/grid.html' );
const oldGetReadableAsBuffer = utils.getReadableAsTypedArray;
sinon.stub(utils, 'getReadableAsTypedArray' ).callsFake(() => {
return oldGetReadableAsBuffer({
getReader() {
return {
done: false ,
read() {
if (!this .done) {
this .done = true ;
return {done: false , value: null };
}
return {done: true };
},
};
},
} as unknown as ReadableStream);
});
const trace = await page.tracing.stop();
expect(trace).toEqual(undefined);
});
it('should support a typedArray without a path' , async () => {
const {page, server} = testState;
await page.tracing.start({screenshots: true });
await page.goto (server.PREFIX + '/grid.html' );
const trace = (await page.tracing.stop())!;
expect(Buffer.from(trace).toString()).toContain('screenshot' );
});
it('should properly fail if readProtocolStream errors out' , async () => {
const {page} = testState;
await page.tracing.start({path: __dirname});
let error!: Error;
try {
await page.tracing.stop();
} catch (error_) {
error = error_ as Error;
}
expect(error).toBeDefined();
});
});
Messung V0.5 in Prozent C=98 H=87 G=92
¤ Dauer der Verarbeitung: 0.19 Sekunden
(vorverarbeitet am 2026-06-04)
¤
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