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How to use StripBom method in Playwright Internal

Best JavaScript code snippet using playwright-internal

bom-test.js

1var assert = require('assert'),2    iconv = require(__dirname+'/../');3var sampleStr = '<?xml version="1.0" encoding="UTF-8"?>\n<ä¿è¯>Ð´Ð°Ð½Ð½ÑÐµ</ä¿è¯>';4    strBOM = '\ufeff',5    utf8BOM = new Buffer([0xEF, 0xBB, 0xBF]),6    utf16beBOM = new Buffer([0xFE, 0xFF]),7    utf16leBOM = new Buffer([0xFF, 0xFE]);8describe("BOM Handling", function() {9    it("strips UTF-8 BOM", function() {10        var body = Buffer.concat([utf8BOM, new Buffer(sampleStr)]);11        assert.equal(iconv.decode(body, 'utf8'), sampleStr);12    });13    it("strips UTF-16 BOM", function() {14        var body = Buffer.concat([utf16leBOM, iconv.encode(sampleStr, 'utf16le')]);15        assert.equal(iconv.decode(body, 'utf16'), sampleStr);16        assert.equal(iconv.decode(body, 'utf16le'), sampleStr);17        var body = Buffer.concat([utf16beBOM, iconv.encode(sampleStr, 'utf16be')]);18        assert.equal(iconv.decode(body, 'utf16'), sampleStr);19        assert.equal(iconv.decode(body, 'utf16be'), sampleStr);20    });21    it("doesn't strip BOMs when stripBOM=false", function() {22        var body = Buffer.concat([utf8BOM, new Buffer(sampleStr)]);23        assert.equal(iconv.decode(body, 'utf8', {stripBOM: false}), strBOM + sampleStr);24        var body = Buffer.concat([utf16leBOM, iconv.encode(sampleStr, 'utf16le')]);25        assert.equal(iconv.decode(body, 'utf16', {stripBOM: false}), strBOM + sampleStr);26        assert.equal(iconv.decode(body, 'utf16le', {stripBOM: false}), strBOM + sampleStr);27        var body = Buffer.concat([utf16beBOM, iconv.encode(sampleStr, 'utf16be')]);28        assert.equal(iconv.decode(body, 'utf16', {stripBOM: false}), strBOM + sampleStr);29        assert.equal(iconv.decode(body, 'utf16be', {stripBOM: false}), strBOM + sampleStr);30    });31    it("adds/strips UTF-7 BOM", function() {32        var bodyWithBOM = iconv.encode(sampleStr, 'utf7', {addBOM: true});33        var body = iconv.encode(sampleStr, 'utf7');34        assert.notEqual(body.toString('hex'), bodyWithBOM.toString('hex'));35        assert.equal(iconv.decode(body, 'utf7'), sampleStr);36    });37    it("adds UTF-8 BOM when addBOM=true", function() {38        var body = Buffer.concat([utf8BOM, new Buffer(sampleStr)]).toString('hex');39        assert.equal(iconv.encode(sampleStr, 'utf8', {addBOM: true}).toString('hex'), body);40    });41    it("adds UTF-16 BOMs when addBOM=true", function() {42        var body = Buffer.concat([utf16leBOM, iconv.encode(sampleStr, 'utf16le')]).toString('hex');43        assert.equal(iconv.encode(sampleStr, 'utf16le', {addBOM: true}).toString('hex'), body);44        var body = Buffer.concat([utf16beBOM, iconv.encode(sampleStr, 'utf16be')]).toString('hex');45        assert.equal(iconv.encode(sampleStr, 'utf16be', {addBOM: true}).toString('hex'), body);46    });47    it("'UTF-16' encoding adds BOM by default, but can be overridden with addBOM=false", function() {48        var body = Buffer.concat([utf16leBOM, iconv.encode(sampleStr, 'utf16le')]).toString('hex');49        assert.equal(iconv.encode(sampleStr, 'utf16').toString('hex'), body);50        var body = Buffer.concat([iconv.encode(sampleStr, 'utf16le')]).toString('hex');51        assert.equal(iconv.encode(sampleStr, 'utf16', {addBOM: false}).toString('hex'), body);52    });53    it("when stripping BOM, calls callback 'stripBOM' if provided", function() {54        var bomStripped = false;55        var stripBOM = function() { bomStripped = true; }56        var body = Buffer.concat([utf8BOM, new Buffer(sampleStr)]);57        assert.equal(iconv.decode(body, 'utf8', {stripBOM: stripBOM}), sampleStr);58        assert(bomStripped);59        bomStripped = false;60        body = new Buffer(sampleStr);61        assert.equal(iconv.decode(body, 'utf8', {stripBOM: stripBOM}), sampleStr);62        assert(!bomStripped);63    });...

preprocessor-adapter.js

Source: preprocessor-adapter.js

1/**2 * "PreprocessorAdapter" creates a generic source transformation API for3 * Browserify, Jest and Node.4 */5'use strict';6var fs = require('fs');7var path = require('path');8var through = require('through2');9var _extensions = ['.js', '.jsx'];10var _rtoplevel = /\bnode_modules\b/;11function _filter(file) {12  return !_rtoplevel.test(file);13}14function withErrorDetails(err, file) {15  err.name = 'PreprocessorAdapter';16  if (typeof file === 'string') {17    err.fileName = file;18    // don't clutter error messages with duplicate file names19    if (String(err.message).indexOf(path.basename(file)) === -1) {20      err.message = file + ': ' + err.message;21    }22  }23  return err;24}25function stripBOM(content) {26  return content.charCodeAt(0) === 0xFEFF ? content.slice(1) : content;27}28function concat(cb) {29  var buffers = [];30  return through(function(chunk, enc, next) {31    buffers.push(chunk);32    next();33  }, function(next) {34    cb.call(this, Buffer.concat(buffers).toString(), next);35  });36}37var registered;38var PreprocessorAdapter = {39  create: function(opts) {40    if (!opts) {41      throw new Error('options are required');42    }43    var transform = opts.transform;44    var extensions = opts.extensions || _extensions;45    var filter = opts.filter || _filter;46    function include(file) {47      var isType = extensions.some(function(ext) {48        return file.indexOf(ext, file.length - ext.length) !== -1;49      });50      return isType && filter(file);51    }52    // browserify - transform53    // https://github.com/substack/node-browserify#btransformtr-opts54    var custom = function(file, options) {55      if (!include(file)) {56        return through();57      }58      return concat(function(src, next) {59        try {60          // no "stripBOM" because browserify will do it's own "stripBOM"61          this.push(transform(src, file));62        } catch(err) {63          this.emit('error', withErrorDetails(err, file));64        }65        next();66      });67    };68    // jest69    // https://facebook.github.io/jest/docs/api.html#config-scriptpreprocessor-string70    custom.process = function(src, file) {71      src = stripBOM(src);72      if (!include(file)) {73        return src;74      }75      try {76        return transform(src, file);77      } catch(err) {78        throw withErrorDetails(err, file);79      }80    };81    // node82    // https://nodejs.org/api/globals.html#globals_require_extensions83    custom.register = function() {84      if (registered) {85        return;86      }87      function compile(module, file) {88        var src = stripBOM(fs.readFileSync(file, 'utf8'));89        var code;90        if (!include(file)) {91          code = src;92        } else {93          try {94            code = transform(src, file);95          } catch(err) {96            throw withErrorDetails(err, file);97          }98        }99        module._compile(code, file);100      }101      extensions.forEach(function(ext) { require.extensions[ext] = compile; });102      registered = true;103    };104    return custom;105  }106};...

strip_bom.js

Source: strip_bom.js

1import { PRINTABLE_ASCII } from '../const';2import v from '../voca';3describe('stripBom', function() {4  it('should strip BOM from the beginning of the string', function() {5    expect(v.stripBom('\uFEFF')).toBe('');6    expect(v.stripBom('\uFEFFHello world!')).toBe('Hello world!');7    expect(v.stripBom('\uFEFF\n\tWelcome')).toBe('\n\tWelcome');8  });9  it('should not affect strings that do not start with BOM', function() {10    expect(v.stripBom('')).toBe('');11    expect(v.stripBom('Hello world!')).toBe('Hello world!');12    expect(v.stripBom('Hello\uFEFFworld!')).toBe('Hello\uFEFFworld!');13    expect(v.stripBom(PRINTABLE_ASCII)).toBe(PRINTABLE_ASCII);14    expect(v.stripBom('\\uFEFF')).toBe('\\uFEFF');15  });16  it('should strip BOM from a string representation of an object', function() {17    expect(v.stripBom('\uFEFFHello world!')).toBe('Hello world!');18    expect(19      v.stripBom({20        toString: function() {21          return '\uFEFFHello world!';22        },23      })24    ).toBe('Hello world!');25  });26  it('should return empty string for null or undefined', function() {27    expect(v.stripBom(null)).toBe('');28    expect(v.stripBom(undefined)).toBe('');29    expect(v.stripBom()).toBe('');30  });...

bom-handling.js

Source: bom-handling.js

1/* */ 2"use strict"3var BOMChar = '\uFEFF';4exports.PrependBOM = PrependBOMWrapper5function PrependBOMWrapper(encoder, options) {6    this.encoder = encoder;7    this.addBOM = true;8}9PrependBOMWrapper.prototype.write = function(str) {10    if (this.addBOM) {11        str = BOMChar + str;12        this.addBOM = false;13    }14    return this.encoder.write(str);15}16PrependBOMWrapper.prototype.end = function() {17    return this.encoder.end();18}19//------------------------------------------------------------------------------20exports.StripBOM = StripBOMWrapper;21function StripBOMWrapper(decoder, options) {22    this.decoder = decoder;23    this.pass = false;24    this.options = options || {};25}26StripBOMWrapper.prototype.write = function(buf) {27    var res = this.decoder.write(buf);28    if (this.pass || !res)29        return res;30    if (res[0] === BOMChar) {31        res = res.slice(1);32        if (typeof this.options.stripBOM === 'function')33            this.options.stripBOM();34    }35    this.pass = true;36    return res;37}38StripBOMWrapper.prototype.end = function() {39    return this.decoder.end();...

4stripbom.js

Source: 4stripbom.js

1'use strict';2describe('jsdoc/util/stripbom', function() {3    var stripBom = require('jsdoc/util/stripbom');4    it('should exist', function() {5        expect(typeof stripBom).toBe('object');6    });7    it('should export a "strip" method', function() {8        expect(typeof stripBom.strip).toBe('function');9    });10    describe('strip', function() {11        it('should strip the leading BOM when present', function() {12            var result = stripBom.strip('\uFEFFHello there!');13            expect(result).toBe('Hello there!');14        });15        it('should not change the text when no leading BOM is present', function() {16            var result = stripBom.strip('Hello there!');17            expect(result).toBe('Hello there!');18        });19        it('should return an empty string when the text is null or undefined', function() {20            expect(stripBom.strip()).toBe('');21        });22    });...

strip-bom

Source: strip-bom

1#!/usr/bin/env node2'use strict';3var fs = require('fs');4var pkg = require('./package.json');5var stripBom = require('./');6var argv = process.argv.slice(2);7var input = argv[0];8function help() {9	console.log([10		'',11		'  ' + pkg.description,12		'',13		'  Usage',14		'    strip-bom <file> > <new-file>',15		'    cat <file> | strip-bom > <new-file>',16		'',17		'  Example',18		'    strip-bom unicorn.txt > unicorn-without-bom.txt'19	].join('\n'));20}21if (argv.indexOf('--help') !== -1) {22	help();23	return;24}25if (argv.indexOf('--version') !== -1) {26	console.log(pkg.version);27	return;28}29if (process.stdin.isTTY) {30	if (!input) {31		help();32		return;33	}34	fs.createReadStream(input).pipe(stripBom.stream()).pipe(process.stdout);35} else {36	process.stdin.pipe(stripBom.stream()).pipe(process.stdout);...

stripBom.js

Source: stripBom.js

1var gulp = require('gulp');2var paths = require('./paths.js');3var stripbom = require('gulp-stripbom');4var stripBom = function (dest) {5    gulp.src([paths.src.scripts, paths.src.exclude.libs])6        .pipe(stripbom({ showLog: false }))7        .pipe(gulp.dest(dest));8    gulp.src(paths.src.less)9        .pipe(stripbom({ showLog: false }))10        .pipe(gulp.dest(dest));11    gulp.src(paths.src.templates)12        .pipe(stripbom({ showLog: false }))13        .pipe(gulp.dest(dest));14};15gulp.task('stripBom', function () {16    stripBom(paths.src.root);...

module.js

Source: module.js

1'use strict';2module.exports.stripBOM = stripBOM;3/**4 * Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)5 * because the buffer-to-string conversion in `fs.readFileSync()`6 * translates it to FEFF, the UTF-16 BOM.7 */8function stripBOM(content) {9  if (content.charCodeAt(0) === 0xFEFF) {10    content = content.slice(1);11  }12  return content;...

Using AI Code Generation

1const fs = require('fs');2const stripBom = require('strip-bom');3const content = fs.readFileSync('test.html', 'utf8');4const strippedContent = stripBom(content);5console.log(strippedContent);6var content = fs.readFileSync('test.html', 'utf8');7var strippedContent = stripBom(content);8console.log(strippedContent);9const fs = require('fs');10const stripBom = require('strip-bom');11const content = fs.readFileSync('test.html', 'utf8');12const strippedContent = stripBom(content);13console.log(strippedContent);14var content = fs.readFileSync('test.html', 'utf8');15var strippedContent = stripBom(content);16console.log(strippedContent);17const fs = require('fs');18const stripBom = require('strip-bom');19const content = fs.readFileSync('test.html', 'utf8');20const strippedContent = stripBom(content);21console.log(strippedContent);22var content = fs.readFileSync('test.html', 'utf8');23var strippedContent = stripBom(content);24console.log(strippedContent);25const fs = require('fs');26const stripBom = require('strip-bom');27const content = fs.readFileSync('test.html', 'utf8');28const strippedContent = stripBom(content);29console.log(strippedContent);30var content = fs.readFileSync('test.html', 'utf8');31var strippedContent = stripBom(content);32console.log(strippedContent);33const fs = require('fs');34const stripBom = require('strip-bom');35const content = fs.readFileSync('test.html', 'utf8');36const strippedContent = stripBom(content);

Using AI Code Generation

1const { stripBom } = require('playwright/lib/utils/encoding');2const fs = require('fs');3const content = fs.readFileSync('test.txt', 'utf8');4const strippedContent = stripBom(content);5console.log(strippedContent);6const { stripBom } = require('playwright/lib/utils/encoding');7const fs = require('fs');8const content = fs.readFileSync('test.txt', 'utf8');9const strippedContent = stripBom(content);10console.log(strippedContent);11const { stripBom } = require('playwright/lib/utils/encoding');12const fs = require('fs');13const content = fs.readFileSync('test.txt', 'utf8');14const strippedContent = stripBom(content);15console.log(strippedContent);16const { stripBom } = require('playwright/lib/utils/encoding');17const fs = require('fs');18const content = fs.readFileSync('test.txt', 'utf8');19const strippedContent = stripBom(content);20console.log(strippedContent);21const { stripBom } = require('playwright/lib/utils/encoding');22const fs = require('fs');23const content = fs.readFileSync('test.txt', 'utf8');24const strippedContent = stripBom(content);25console.log(strippedContent);26const { stripBom } = require('playwright/lib/utils/encoding');27const fs = require('fs');28const content = fs.readFileSync('test.txt', 'utf8');29const strippedContent = stripBom(content);30console.log(strippedContent);31const { stripBom } = require('playwright/lib/utils/encoding');32const fs = require('fs');33const content = fs.readFileSync('test.txt', 'utf8');34const strippedContent = stripBom(content);35console.log(strippedContent);36const { stripBom } = require('playwright/lib/utils/encoding');37const fs = require('fs');38const content = fs.readFileSync('test.txt', 'utf8');39const strippedContent = stripBom(content);40console.log(strippedContent);41const { stripBom } = require('playwright/lib/utils/encoding');

Using AI Code Generation

1const { Internal } = require('playwright');2const fs = require('fs');3const { stripBom } = new Internal();4const file = fs.readFileSync('./test.txt', 'utf8');5const strippedFile = stripBom(file);6console.log(strippedFile);7const test = 'Hello World';8const test = '\uFEFFHello World';9const test = 'Hello World';10const test = '\uFEFFHello World';11const test = 'Hello World';12const test = '\uFEFFHello World';13const test = 'Hello World';14const test = '\uFEFFHello World';15const test = 'Hello World';16const test = '\uFEFFHello World';17const test = 'Hello World';18const test = '\uFEFFHello World';19const test = 'Hello World';20const test = '\uFEFFHello World';21const test = 'Hello World';22const test = '\uFEFFHello World';23const test = 'Hello World';24const test = '\uFEFFHello World';25const test = 'Hello World';26const test = '\uFEFFHello World';27const test = 'Hello World';28const test = '\uFEFFHello World';29const test = 'Hello World';30const test = '\uFEFFHello World';31const test = 'Hello World';32const test = '\uFEFFHello World';

Using AI Code Generation

1const { StripBom } = require('@playwright/test/lib/utils/bom');2const fs = require('fs');3const path = require('path');4const testFile = fs.readFileSync(path.join(__dirname, 'test.txt'), 'utf8');5const strippedFile = StripBom(testFile);6console.log(strippedFile);

Using AI Code Generation

1const fs = require('fs');2const stripBom = require('strip-bom');3const path = require('path');4const file = fs.readFileSync('test.txt', 'utf8');5const stripped = stripBom(file);6fs.writeFileSync('test.txt', stripped);7console.log('BOM removed successfully');8const fs = require('fs');9const stripBom = require('strip-bom');10const path = require('path');11const file = fs.readFileSync('test.txt', 'utf8');12const stripped = stripBom(file);13fs.writeFileSync('test.txt', stripped);14console.log('BOM removed successfully');15const fs = require('fs');16const stripBom = require('strip-bom');17const path = require('path');18const file = fs.readFileSync('test.txt', 'utf8');19const stripped = stripBom(file);20fs.writeFileSync('test.txt', stripped);21console.log('BOM removed successfully');22const fs = require('fs');23const stripBom = require('strip-bom');24const path = require('path');25const file = fs.readFileSync('test.txt', 'utf8');26const stripped = stripBom(file);27fs.writeFileSync('test.txt', stripped);28console.log('BOM removed successfully');29const fs = require('fs');30const stripBom = require('strip-bom');31const path = require('path');32const file = fs.readFileSync('test.txt', 'utf8');33const stripped = stripBom(file);34fs.writeFileSync('test.txt', stripped);35console.log('BOM removed

StackOverFlow community discussions

Questions

Discussion

Is it possible to get the selector from a locator object in playwright?

firefox browser does not start in playwright

How to run a list of test suites in a single file concurrently in jest?

firefox browser does not start in playwright

Jest + Playwright - Test callbacks of event-based DOM library

Running Playwright in Azure Function

Well this is one way, but not sure if it will work for all possible locators!.

// Get a selector from a playwright locator
import { Locator } from "@playwright/test";
export function extractSelector(locator: Locator) {
    const selector = locator.toString();
    const parts = selector.split("@");
    if (parts.length !== 2) { throw Error("extractSelector: susupect that this is not a locator"); }
    if (parts[0] !== "Locator") { throw Error("extractSelector: did not find locator"); }
    return parts[1];
}

https://stackoverflow.com/questions/72044959/is-it-possible-to-get-the-selector-from-a-locator-object-in-playwright

I found the error. It was because of some missing libraries need. I discovered this when I downgraded playwright to version 1.9 and ran the the code then this was the error msg:

(node:12876) UnhandledPromiseRejectionWarning: browserType.launch: Host system is missing dependencies!

Some of the Universal C Runtime files cannot be found on the system. You can fix
that by installing Microsoft Visual C++ Redistributable for Visual Studio from:
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Full list of missing libraries:
    vcruntime140.dll
    msvcp140.dll
Error
    at Object.captureStackTrace (D:\Projects\snkrs-play\node_modules\playwright\lib\utils\stackTrace.js:48:19)
    at Connection.sendMessageToServer (D:\Projects\snkrs-play\node_modules\playwright\lib\client\connection.js:69:48)
    at Proxy.<anonymous> (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:64:61)
    at D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:64:67
    at BrowserType._wrapApiCall (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:77:34)
    at BrowserType.launch (D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:55:21)
    at D:\Projects\snkrs-play\index.js:4:35
    at Object.<anonymous> (D:\Projects\snkrs-play\index.js:7:3)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12876) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12876) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

A list of missing libraries was provided. After successful installments, firefox ran fine. I upgraded again to version 1.10 and firefox still works.

https://stackoverflow.com/questions/66984974/firefox-browser-does-not-start-in-playwright

Assuming you are not running test with the --runinband flag, the simple answer is yes but it depends ????

There is a pretty comprehensive GitHub issue jest#6957 that explains certain cases of when tests are run concurrently or in parallel. But it seems to depend on a lot of edge cases where jest tries its best to determine the fastest way to run the tests given the circumstances.

To my knowledge there is no way to force jest to run in parallel.

Aside

Have you considered using playwright instead of puppeteer with jest? Playwright has their own internally built testing library called @playwright/test that is used in place of jest with a similar API. This library allows for explicitly defining test groups in a single file to run in parallel (i.e. test.describe.parallel) or serially (i.e. test.describe.serial). Or even to run all tests in parallel via a config option.

// parallel
test.describe.parallel('group', () => {
  test('runs in parallel 1', async ({ page }) => {});
  test('runs in parallel 2', async ({ page }) => {});
});

// serial
test.describe.serial('group', () => {
  test('runs first', async ({ page }) => {});
  test('runs second', async ({ page }) => {});
});

https://stackoverflow.com/questions/73497773/how-to-run-a-list-of-test-suites-in-a-single-file-concurrently-in-jest

I found the error. It was because of some missing libraries need. I discovered this when I downgraded playwright to version 1.9 and ran the the code then this was the error msg:

(node:12876) UnhandledPromiseRejectionWarning: browserType.launch: Host system is missing dependencies!

Some of the Universal C Runtime files cannot be found on the system. You can fix
that by installing Microsoft Visual C++ Redistributable for Visual Studio from:
https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Full list of missing libraries:
    vcruntime140.dll
    msvcp140.dll
Error
    at Object.captureStackTrace (D:\Projects\snkrs-play\node_modules\playwright\lib\utils\stackTrace.js:48:19)
    at Connection.sendMessageToServer (D:\Projects\snkrs-play\node_modules\playwright\lib\client\connection.js:69:48)
    at Proxy.<anonymous> (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:64:61)
    at D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:64:67
    at BrowserType._wrapApiCall (D:\Projects\snkrs-play\node_modules\playwright\lib\client\channelOwner.js:77:34)
    at BrowserType.launch (D:\Projects\snkrs-play\node_modules\playwright\lib\client\browserType.js:55:21)
    at D:\Projects\snkrs-play\index.js:4:35
    at Object.<anonymous> (D:\Projects\snkrs-play\index.js:7:3)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:12876) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:12876) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

A list of missing libraries was provided. After successful installments, firefox ran fine. I upgraded again to version 1.10 and firefox still works.

https://stackoverflow.com/questions/66984974/firefox-browser-does-not-start-in-playwright

This question is quite close to a "need more focus" question. But let's try to give it some focus:

Does Playwright has access to the cPicker object on the page? Does it has access to the window object?

Yes, you can access both cPicker and the window object inside an evaluate call.

Should I trigger the events from the HTML file itself, and in the callbacks, print in the DOM the result, in some dummy-element, and then infer from that dummy element text that the callbacks fired?

Exactly, or you can assign values to a javascript variable:

const cPicker = new ColorPicker({
  onClickOutside(e){
  },
  onInput(color){
    window['color'] = color;
  },
  onChange(color){
    window['result'] = color;
  }
})

And then

it('Should call all callbacks with correct arguments', async() => {
    await page.goto(`http://localhost:5000/tests/visual/basic.html`, {waitUntil:'load'})

    // Wait until the next frame
    await page.evaluate(() => new Promise(requestAnimationFrame))

    // Act
   
    // Assert
    const result = await page.evaluate(() => window['color']);
    // Check the value
})

https://stackoverflow.com/questions/65477895/jest-playwright-test-callbacks-of-event-based-dom-library

Blogs

Check out the latest blogs from LambdaTest on this topic:

Using ChatGPT for Test Automation

ChatGPT broke all Internet records by going viral in the first week of its launch. A million users in 5 days are unprecedented. A conversational AI that can answer natural language-based questions and create poems, write movie scripts, write social media posts, write descriptive essays, and do tons of amazing things. Our first thought when we got access to the platform was how to use this amazing platform to make the lives of web and mobile app testers easier. And most importantly, how we can use ChatGPT for automated testing.

A Reconsideration of Software Testing Metrics

There is just one area where each member of the software testing community has a distinct point of view! Metrics! This contentious issue sparks intense disputes, and most conversations finish with no definitive conclusion. It covers a wide range of topics: How can testing efforts be measured? What is the most effective technique to assess effectiveness? Which of the many components should be quantified? How can we measure the quality of our testing performance, among other things?

Desired Capabilities in Selenium Webdriver

Desired Capabilities is a class used to declare a set of basic requirements such as combinations of browsers, operating systems, browser versions, etc. to perform automated cross browser testing of a web application.

Putting Together a Testing Team

As part of one of my consulting efforts, I worked with a mid-sized company that was looking to move toward a more agile manner of developing software. As with any shift in work style, there is some bewilderment and, for some, considerable anxiety. People are being challenged to leave their comfort zones and embrace a continuously changing, dynamic working environment. And, dare I say it, testing may be the most ‘disturbed’ of the software roles in agile development.

How To Automate Desktops Apps Using WinAppDriver

Playwright tutorial

LambdaTest’s Playwright tutorial will give you a broader idea about the Playwright automation framework, its unique features, and use cases with examples to exceed your understanding of Playwright testing. This tutorial will give A to Z guidance, from installing the Playwright framework to some best practices and advanced concepts.

Chapters:

What is Playwright : Playwright is comparatively new but has gained good popularity. Get to know some history of the Playwright with some interesting facts connected with it.
How To Install Playwright : Learn in detail about what basic configuration and dependencies are required for installing Playwright and run a test. Get a step-by-step direction for installing the Playwright automation framework.
Playwright Futuristic Features: Launched in 2020, Playwright gained huge popularity quickly because of some obliging features such as Playwright Test Generator and Inspector, Playwright Reporter, Playwright auto-waiting mechanism and etc. Read up on those features to master Playwright testing.
What is Component Testing: Component testing in Playwright is a unique feature that allows a tester to test a single component of a web application without integrating them with other elements. Learn how to perform Component testing on the Playwright automation framework.
Inputs And Buttons In Playwright: Every website has Input boxes and buttons; learn about testing inputs and buttons with different scenarios and examples.
Functions and Selectors in Playwright: Learn how to launch the Chromium browser with Playwright. Also, gain a better understanding of some important functions like “BrowserContext,” which allows you to run multiple browser sessions, and “newPage” which interacts with a page.
Handling Alerts and Dropdowns in Playwright : Playwright interact with different types of alerts and pop-ups, such as simple, confirmation, and prompt, and different types of dropdowns, such as single selector and multi-selector get your hands-on with handling alerts and dropdown in Playright testing.
Playwright vs Puppeteer: Get to know about the difference between two testing frameworks and how they are different than one another, which browsers they support, and what features they provide.
Run Playwright Tests on LambdaTest: Playwright testing with LambdaTest leverages test performance to the utmost. You can run multiple Playwright tests in Parallel with the LammbdaTest test cloud. Get a step-by-step guide to run your Playwright test on the LambdaTest platform.
Playwright Python Tutorial: Playwright automation framework support all major languages such as Python, JavaScript, TypeScript, .NET and etc. However, there are various advantages to Python end-to-end testing with Playwright because of its versatile utility. Get the hang of Playwright python testing with this chapter.
Playwright End To End Testing Tutorial: Get your hands on with Playwright end-to-end testing and learn to use some exciting features such as TraceViewer, Debugging, Networking, Component testing, Visual testing, and many more.
Playwright Video Tutorial: Watch the video tutorials on Playwright testing from experts and get a consecutive in-depth explanation of Playwright automation testing.