How to use assertionErrorMessage method in Jest
Best JavaScript code snippet using jest
assertions.test.js
Source:assertions.test.js 
1const { expect, AssertionError } = require('./test-helper')2const { Success, Failure } = require('kekka')3describe('assertions', () => {4 describe('result', () => {5 const isAResultAssertion = function (value) {6 return () => expect(value).to.be.a.result7 }8 it('should succeed if value is a Result instance', () => {9 const someSuccessResult = Success('Some String')10 const someFailureResult = Failure(new Error('Failure...'))11 expect(isAResultAssertion(someSuccessResult)).not.to.throw()12 expect(isAResultAssertion(someFailureResult)).not.to.throw()13 })14 it('should fail if value is a not a Result instance', () => {15 const notAResult = 'Some String'16 const assertionErrorMessage = '\'Some String\' to be an instance of Result'17 expect(isAResultAssertion(notAResult)).to.throw(AssertionError, assertionErrorMessage)18 })19 })20 describe('success', () => {21 const isASuccessAssertion = function (value) {22 return () => expect(value).to.be.a.success23 }24 it('should succeed if value is a Success', () => {25 const someSuccessResult = Success('Some String')26 expect(isASuccessAssertion(someSuccessResult)).not.to.throw()27 })28 it('should fail if value is a Failure', () => {29 const someFailureResult = Failure(new Error('Failure...'))30 const assertionErrorMessage = 'expected [Result-Failure (Error: Failure...)] to be a success'31 expect(isASuccessAssertion(someFailureResult)).to.throw(AssertionError, assertionErrorMessage)32 })33 it('should fail if value is a not a Result instance', () => {34 const notAResult = 'Some String'35 const assertionErrorMessage = '\'Some String\' to be an instance of Result'36 expect(isASuccessAssertion(notAResult)).to.throw(AssertionError, assertionErrorMessage)37 })38 it('should negate only the success vs failure part', () => {39 const notAResult = 'Some String'40 const someSuccessResult = Success('Some String')41 const someFailureResult = Failure(new Error('Failure...'))42 const isNotASuccessAssertion = function (value) {43 return () => expect(value).to.not.be.a.success44 }45 const assertionErrorMessage1 = 'expected [Result-Success (Some String)] not to be a success'46 expect(isNotASuccessAssertion(someSuccessResult)).to.throw(AssertionError, assertionErrorMessage1)47 expect(isNotASuccessAssertion(someFailureResult)).not.to.throw()48 const assertionErrorMessage2 = 'expected \'Some String\' to be an instance of Result'49 expect(isNotASuccessAssertion(notAResult)).to.throw(AssertionError, assertionErrorMessage2)50 })51 })52 describe('successWrapping', () => {53 const isSuccessWrappingAssertion = function (value, expectedValue) {54 return () => expect(value).to.be.a.successWrapping(expectedValue)55 }56 const isDeepSuccessWrappingAssertion = function (value, expectedValue) {57 return () => expect(value).to.be.a.deep.successWrapping(expectedValue)58 }59 it('should succeed if value is a Success wrapping the right value', () => {60 const associatedValue = 'string'61 const someSuccessResult = Success('string')62 expect(isSuccessWrappingAssertion(someSuccessResult, associatedValue)).not.to.throw()63 })64 it('should succeed with a deep equality', () => {65 const associatedObject = { a: '423' }66 const someSuccessResult = Success({ a: '423' })67 const assertionErrorMessage = 'expected { a: \'423\' } to equal { a: \'423\' }'68 expect(isSuccessWrappingAssertion(someSuccessResult, associatedObject)).to.throw(AssertionError, assertionErrorMessage)69 expect(isDeepSuccessWrappingAssertion(someSuccessResult, associatedObject)).not.to.throw()70 })71 it('should fail if value is a Failure', () => {72 const someFailureResult = Failure(new Error('Failure...'))73 const assertionErrorMessage = 'expected [Result-Failure (Error: Failure...)] to be a success'74 expect(isSuccessWrappingAssertion(someFailureResult, 'not useful')).to.throw(AssertionError, assertionErrorMessage)75 })76 it('should fail if value is not a result', () => {77 const notAResult = 'not a result'78 const assertionErrorMessage = '\'not a result\' to be an instance of Result'79 expect(isSuccessWrappingAssertion(notAResult, 'not useful')).to.throw(AssertionError, assertionErrorMessage)80 })81 })82 describe('failure', () => {83 const isAFailureAssertion = function (value) {84 return () => expect(value).to.be.a.failure85 }86 it('should succeed if value is a Failure', () => {87 const someFailureResult = Failure(new Error('Failure...'))88 expect(isAFailureAssertion(someFailureResult)).not.to.throw()89 })90 it('should fail if value is a Success', () => {91 const someSuccessResult = Success('Some String')92 const assertionErrorMessage = 'expected [Result-Success (Some String)] to be a failure'93 expect(isAFailureAssertion(someSuccessResult)).to.throw(AssertionError, assertionErrorMessage)94 })95 it('should fail if value is a not a Result instance', () => {96 const notAResult = 'Some String'97 const assertionErrorMessage = '\'Some String\' to be an instance of Result'98 expect(isAFailureAssertion(notAResult)).to.throw(AssertionError, assertionErrorMessage)99 })100 it('should negate only the success vs failure part', () => {101 const notAResult = 'Some String'102 const someSuccessResult = Success('Some String')103 const someFailureResult = Failure(new Error('Failure...'))104 const isNotAFailureAssertion = function (value) {105 return () => expect(value).to.not.be.a.failure106 }107 expect(isNotAFailureAssertion(someSuccessResult)).not.to.throw()108 const assertionErrorMessage1 = 'expected [Result-Failure (Error: Failure...)] not to be a failure'109 expect(isNotAFailureAssertion(someFailureResult)).to.throw(AssertionError, assertionErrorMessage1)110 const assertionErrorMessage2 = 'expected \'Some String\' to be an instance of Result'111 expect(isNotAFailureAssertion(notAResult)).to.throw(AssertionError, assertionErrorMessage2)112 })113 })114 describe('failureWrapping', () => {115 const isFailureWrappingAssertion = function (value, expectedValue) {116 return () => expect(value).to.be.a.failureWrapping(expectedValue)117 }118 it('should succeed if value is a Failure wrapping the right value', () => {119 const associatedError = new Error('Failure...')120 const someFailureResult = Failure(associatedError)121 expect(isFailureWrappingAssertion(someFailureResult, associatedError)).not.to.throw()122 })123 it('should fail if value is a Success', () => {124 const someSuccessResult = Success('Some String')125 const assertionErrorMessage = 'expected [Result-Success (Some String)] to be a failure'126 expect(isFailureWrappingAssertion(someSuccessResult, 'not useful')).to.throw(AssertionError, assertionErrorMessage)127 })128 it('should fail if value is not a result', () => {129 const notAResult = 'not a result'130 const assertionErrorMessage = '\'not a result\' to be an instance of Result'131 expect(isFailureWrappingAssertion(notAResult, 'not useful')).to.throw(AssertionError, assertionErrorMessage)132 })133 })134 describe('associatedValue', () => {135 it('should succeed if associated value equals expected', () => {136 const expectedValue = 'Some String'137 const someSuccessResult = Success('Some String')138 const isASuccessAssociatedValueAssertion = function (value, expected) {139 return () => expect(value).to.be.a.success.with.associatedValue.that.equals(expected)140 }141 expect(isASuccessAssociatedValueAssertion(someSuccessResult, expectedValue)).not.to.throw()142 })143 it('should work also with failure result type', () => {144 const expectedValue = new Error('Some Failure')145 const someFailureResult = Failure(expectedValue)146 const isAFailureAssociatedValueAssertion = function (value, expected) {147 return () => expect(value).to.be.a.failure.with.associatedValue.that.equals(expected)148 }149 expect(isAFailureAssociatedValueAssertion(someFailureResult, expectedValue)).not.to.throw()150 })151 it('should work also with result property', () => {152 const expectedValue = 'Some String'153 const someSuccessResult = Success('Some String')154 const isAResultAssociatedValueAssertion = function (value, expected) {155 return () => expect(value).to.be.a.result.with.associatedValue.that.equals(expected)156 }157 expect(isAResultAssociatedValueAssertion(someSuccessResult, expectedValue)).not.to.throw()158 })159 it('should work also with deep equality assertion', () => {160 const expectedObject = { a: 'property' }161 const someSuccessResult = Success({ a: 'property' })162 const isASuccessAssociatedValueAssertion = function (value, expected) {163 return () => expect(value).to.be.a.success.with.associatedValue.that.deep.equals(expected)164 }165 expect(isASuccessAssociatedValueAssertion(someSuccessResult, expectedObject)).not.to.throw()166 })167 it('should not work if no test of result was done before hand', () => {168 const expectedValue = 'Some String'169 const someSuccessResult = Success('Some String')170 const noResultCheckAssertion = function (value, expected) {171 return () => expect(value).to.have.an.associatedValue.that.equals(expected)172 }173 const assertionErrorMessage = 'No Result check done,' +174 ' use \'result\', \'success\', or \'failure\' assertion before \'associatedValue\''175 expect(noResultCheckAssertion(someSuccessResult, expectedValue)).to.throw(AssertionError, assertionErrorMessage)176 })177 })...
Spec.js
Source:Spec.js
...126 if (error instanceof ExpectationFailed) {127 return;128 }129 if (error instanceof AssertionError) {130 error = assertionErrorMessage(error, {expand: this.expand});131 }132 this.addExpectationResult(133 false,134 {135 matcherName: '',136 passed: false,137 expected: '',138 actual: '',139 error,140 },141 true,142 );143};144Spec.prototype.disable = function() {...
assert-support.js
Source:assert-support.js
...60 chalk.dim(') ');61 }62 return message;63};64function assertionErrorMessage(error, options) {const65 expected = error.expected,actual = error.actual,message = error.message,operator = error.operator,stack = error.stack;66 const diffString = diff(expected, actual, options);67 const negator =68 typeof operator === 'string' && (69 operator.startsWith('!') || operator.startsWith('not'));70 const hasCustomMessage = !error.generatedMessage;71 const operatorName = getOperatorName(operator, stack);72 if (operatorName === 'doesNotThrow') {73 return (74 assertThrowingMatcherHint(operatorName) +75 '\n\n' +76 chalk.reset(`Expected the function not to throw an error.\n`) +77 chalk.reset(`Instead, it threw:\n`) +78 ` ${printReceived(actual)}` +...
assert_support.js
Source:assert_support.js
...76 _chalk2.default.dim(') ');77 }78 return message;79};80function assertionErrorMessage(error, options) {81 const expected = error.expected,82 actual = error.actual,83 generatedMessage = error.generatedMessage,84 message = error.message,85 operator = error.operator,86 stack = error.stack;87 const diffString = (0, _jestDiff2.default)(expected, actual, options);88 const hasCustomMessage = !generatedMessage;89 const operatorName = getOperatorName(operator, stack);90 const trimmedStack = stack91 .replace(message, '')92 .replace(/AssertionError(.*)/g, '');93 if (operatorName === 'doesNotThrow') {94 return (...
format_node_assert_errors.js
Source:format_node_assert_errors.js
...38 case 'test_failure':39 case 'test_success': {40 event.test.errors = event.test.errors.map(error => {41 return error instanceof require('assert').AssertionError42 ? assertionErrorMessage(error, {expand: state.expand})43 : error;44 });45 break;46 }47 }48};49const getOperatorName = (operator: ?string, stack: string) => {50 if (typeof operator === 'string') {51 return assertOperatorsMap[operator] || operator;52 }53 if (stack.match('.doesNotThrow')) {54 return 'doesNotThrow';55 }56 if (stack.match('.throws')) {57 return 'throws';58 }59 return '';60};61const operatorMessage = (operator: ?string, negator: boolean) =>62 typeof operator === 'string'63 ? operator.startsWith('!') || operator.startsWith('=')64 ? `${negator ? 'not ' : ''}to be (operator: ${operator}):\n`65 : `${humanReadableOperators[operator] || operator} to:\n`66 : '';67const assertThrowingMatcherHint = (operatorName: string) => {68 return (69 chalk.dim('assert') +70 chalk.dim('.' + operatorName + '(') +71 chalk.red('function') +72 chalk.dim(')')73 );74};75const assertMatcherHint = (operator: ?string, operatorName: string) => {76 let message =77 chalk.dim('assert') +78 chalk.dim('.' + operatorName + '(') +79 chalk.red('received') +80 chalk.dim(', ') +81 chalk.green('expected') +82 chalk.dim(')');83 if (operator === '==') {84 message +=85 ' or ' +86 chalk.dim('assert') +87 chalk.dim('(') +88 chalk.red('received') +89 chalk.dim(') ');90 }91 return message;92};93function assertionErrorMessage(error: AssertionError, options: DiffOptions) {94 const {expected, actual, message, operator, stack} = error;95 const diffString = diff(expected, actual, options);96 const negator =97 typeof operator === 'string' &&98 (operator.startsWith('!') || operator.startsWith('not'));99 const hasCustomMessage = !error.generatedMessage;100 const operatorName = getOperatorName(operator, stack);101 if (operatorName === 'doesNotThrow') {102 return (103 assertThrowingMatcherHint(operatorName) +104 '\n\n' +105 chalk.reset(`Expected the function not to throw an error.\n`) +106 chalk.reset(`Instead, it threw:\n`) +107 ` ${printReceived(actual)}` +...
assertionErrorMessage.js
Source:assertionErrorMessage.js
...77 chalk.dim(') ');78 }79 return message;80};81function assertionErrorMessage(error: AssertionError, options: DiffOptions) {82 const {expected, actual, generatedMessage, message, operator, stack} = error;83 const diffString = diff(expected, actual, options);84 const hasCustomMessage = !generatedMessage;85 const operatorName = getOperatorName(operator, stack);86 const trimmedStack = stack87 .replace(message, '')88 .replace(/AssertionError(.*)/g, '');89 if (operatorName === 'doesNotThrow') {90 return (91 assertThrowingMatcherHint(operatorName) +92 '\n\n' +93 chalk.reset(`Expected the function not to throw an error.\n`) +94 chalk.reset(`Instead, it threw:\n`) +95 ` ${printReceived(actual)}` +...
greeter_test.js
Source:greeter_test.js
1const GreeterContract = artifacts.require("Greeter");2contract("Greeter", (accounts) => {3 it("Has been deployed", async () => {4 const greeter = await GreeterContract.deployed();5 assert(greeter, "Contract was not deployed");6 });7 describe("greet()", () => {8 it("Returns 'Hello, World!'", async () => {9 const greeter = await GreeterContract.deployed();10 const expected = "Hello, World!";11 const actual = await greeter.greet();12 13 assert.equal(actual, expected, "Not greeted with 'Hello, World!'");14 });15 });16 describe("owner()", () => {17 it("Returns the owner's address", async () => {18 const greeter = await GreeterContract.deployed();19 const owner = await greeter.owner();20 assert(owner, "It's not the current owner");21 });22 it("Matches the address that deployed the contract", async () => {23 const greeter = await GreeterContract.deployed();24 const owner = await greeter.owner();25 const expected = accounts[0];26 assert.equal(owner, expected, "Greeter setter account does not match with original");27 });28 });29});30contract("Greeter: update greeting", (accounts) => {31 describe("setGreeting(string)", () => {32 describe("When message is set by the owner", () => {33 it("Sets greeting based on parameter", async () => {34 const greeter = await GreeterContract.deployed();35 const expected = "Hey, I can modify the message!";36 37 await greeter.setGreeting(expected);38 const actual = await greeter.greet();39 40 assert.equal(actual, expected, "Greeting was not updated correctly");41 });42 });43 describe("When message is set by another account", () => {44 it("Does not set the greeting", async () => {45 const assertionErrorMessage = "Greeting shold not be updated by other account than the original";46 const greeter = await GreeterContract.deployed();47 try {48 await greeter.setGreeting("Mmm... I shouldn't be enabled to set this...", {49 from: accounts[1]50 });51 } catch(err) {52 const errMessage = "Ownable: caller is not the owner";53 assert.equal(err.reason, errMessage, assertionErrorMessage);54 return;55 }56 assert(false, assertionErrorMessage);57 });58 });59 });...
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