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How to use buildHintString method in Jest

Best JavaScript code snippet using jest

formatNodeAssertErrors.js

Source:formatNodeAssertErrors.js

...120    .replace(message, '')121    .replace(/AssertionError(.*)/g, '');122  if (operatorName === 'doesNotThrow') {123    return (124      buildHintString(assertThrowingMatcherHint(operatorName)) +125      _chalk.default.reset(`Expected the function not to throw an error.\n`) +126      _chalk.default.reset(`Instead, it threw:\n`) +127      `  ${(0, _jestMatcherUtils.printReceived)(actual)}` +128      _chalk.default.reset(129        hasCustomMessage ? '\n\nMessage:\n  ' + message : ''130      ) +131      trimmedStack132    );133  }134  if (operatorName === 'throws') {135    return (136      buildHintString(assertThrowingMatcherHint(operatorName)) +137      _chalk.default.reset(`Expected the function to throw an error.\n`) +138      _chalk.default.reset(`But it didn't throw anything.`) +139      _chalk.default.reset(140        hasCustomMessage ? '\n\nMessage:\n  ' + message : ''141      ) +142      trimmedStack143    );144  }145  if (operatorName === 'fail') {146    return (147      buildHintString(assertMatcherHint(operator, operatorName, expected)) +148      _chalk.default.reset(hasCustomMessage ? 'Message:\n  ' + message : '') +149      trimmedStack150    );151  }152  return (153    buildHintString(assertMatcherHint(operator, operatorName, expected)) +154    _chalk.default.reset(`Expected value ${operatorMessage(operator)}`) +155    `  ${(0, _jestMatcherUtils.printExpected)(expected)}\n` +156    _chalk.default.reset(`Received:\n`) +157    `  ${(0, _jestMatcherUtils.printReceived)(actual)}` +158    _chalk.default.reset(hasCustomMessage ? '\n\nMessage:\n  ' + message : '') +159    (diffString ? `\n\nDifference:\n\n${diffString}` : '') +160    trimmedStack161  );162}163function isAssertionError(error) {164  return (165    error &&166    (error instanceof _assert.AssertionError ||167      error.name === _assert.AssertionError.name ||168      error.code === 'ERR_ASSERTION')169  );170}171function buildHintString(hint) {172  return hint ? hint + '\n\n' : '';173}174var _default = formatNodeAssertErrors;...

assertionErrorMessage.js

Source:assertionErrorMessage.js

...87    .replace(message, '')88    .replace(/AssertionError(.*)/g, '');89  if (operatorName === 'doesNotThrow') {90    return (91      buildHintString(assertThrowingMatcherHint(operatorName)) +92      _chalk.default.reset(`Expected the function not to throw an error.\n`) +93      _chalk.default.reset(`Instead, it threw:\n`) +94      `  ${(0, _jestMatcherUtils.printReceived)(actual)}` +95      _chalk.default.reset(96        hasCustomMessage ? '\n\nMessage:\n  ' + message : ''97      ) +98      trimmedStack99    );100  }101  if (operatorName === 'throws') {102    return (103      buildHintString(assertThrowingMatcherHint(operatorName)) +104      _chalk.default.reset(`Expected the function to throw an error.\n`) +105      _chalk.default.reset(`But it didn't throw anything.`) +106      _chalk.default.reset(107        hasCustomMessage ? '\n\nMessage:\n  ' + message : ''108      ) +109      trimmedStack110    );111  }112  if (operatorName === 'fail') {113    return (114      buildHintString(assertMatcherHint(operator, operatorName, expected)) +115      _chalk.default.reset(hasCustomMessage ? 'Message:\n  ' + message : '') +116      trimmedStack117    );118  }119  return (120    buildHintString(assertMatcherHint(operator, operatorName, expected)) +121    _chalk.default.reset(`Expected value ${operatorMessage(operator)}`) +122    `  ${(0, _jestMatcherUtils.printExpected)(expected)}\n` +123    _chalk.default.reset(`Received:\n`) +124    `  ${(0, _jestMatcherUtils.printReceived)(actual)}` +125    _chalk.default.reset(hasCustomMessage ? '\n\nMessage:\n  ' + message : '') +126    (diffString ? `\n\nDifference:\n\n${diffString}` : '') +127    trimmedStack128  );129}130function buildHintString(hint) {131  return hint ? hint + '\n\n' : '';132}133var _default = assertionErrorMessage;...

Jest Testing Tutorial

LambdaTest’s Jest Testing Tutorial covers step-by-step guides around Jest with code examples to help you be proficient with the Jest framework. The Jest tutorial has chapters to help you learn right from the basics of Jest framework to code-based tutorials around testing react apps with Jest, perform snapshot testing, import ES modules and more.

Chapters

What is Jest Framework
Advantages of Jest - Jest has 3,898,000 GitHub repositories, as mentioned on its official website. Learn what makes Jest special and why Jest has gained popularity among the testing and developer community.
Jest Installation - All the prerequisites and set up steps needed to help you start Jest automation testing.
Using Jest with NodeJS Project - Learn how to leverage Jest framework to automate testing using a NodeJS Project.
Writing First Test for Jest Framework - Get started with code-based tutorial to help you write and execute your first Jest framework testing script.
Jest Vocabulary - Learn the industry renowned and official jargons of the Jest framework by digging deep into the Jest vocabulary.
Unit Testing with Jest - Step-by-step tutorial to help you execute unit testing with Jest framework.
Jest Basics - Learn about the most pivotal and basic features which makes Jest special.
Jest Parameterized Tests - Avoid code duplication and fasten automation testing with Jest using parameterized tests. Parameterization allows you to trigger the same test scenario over different test configurations by incorporating parameters.
Jest Matchers - Enforce assertions better with the help of matchers. Matchers help you compare the actual output with the expected one. Here is an example to see if the object is acquired from the correct class or not. -

|it('check_object_of_Car', () => { expect(newCar()).toBeInstanceOf(Car); });| | :- |

Jest Hooks: Setup and Teardown - Learn how to set up conditions which needs to be followed by the test execution and incorporate a tear down function to free resources after the execution is complete.
Jest Code Coverage - Unsure there is no code left unchecked in your application. Jest gives a specific flag called --coverage to help you generate code coverage.
HTML Report Generation - Learn how to create a comprehensive HTML report based on your Jest test execution.
Testing React app using Jest Framework - Learn how to test your react web-application with Jest framework in this detailed Jest tutorial.
Test using LambdaTest cloud Selenium Grid - Run your Jest testing script over LambdaTest cloud-based platform and leverage parallel testing to help trim down your test execution time.
Snapshot Testing for React Front Ends - Capture screenshots of your react based web-application and compare them automatically for visual anomalies with the help of Jest tutorial.
Bonus: Import ES modules with Jest - ES modules are also known as ECMAScript modules. Learn how to best use them by importing in your Jest testing scripts.
Jest vs Mocha vs Jasmine - Learn the key differences between the most popular JavaScript-based testing frameworks i.e. Jest, Mocha, and Jasmine.
Jest FAQs(Frequently Asked Questions) - Explore the most commonly asked questions around Jest framework, with their answers.