@japa/errors-printer

> Error printer to pretty print Japa errors

[![github-actions-image]][github-actions-url] [![npm-image]][npm-url] [![license-image]][license-url] [![typescript-image]][typescript-url]

Installation

Install the package from the npm registry as follows:

``sh
npm i @japa/errors-printer
`

`sh
yarn add @japa/errors-printer
`

`sh
pnpm add @japa/errors-printer
`

Usage

You can print errors produced by japa test runner as follows.

`ts
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()
const error = new Error('boom')

await printer.printError(error)
`

Most of the times, you will find yourself printing errors using the Japa test summary. Here is how you can go about doing it.

`ts
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()

// assuming you have the runner instance
const summary = runner.getSummary()
const errorsList = []

summary.failureTree.forEach((suite) => {
suite.errors.forEach((error) => {
errorsList.push({ title: suite.name, ...error })
})

suite.children.forEach((groupOrTest) => {
if (groupOrTest.type === 'test') {
groupOrTest.errors.forEach((error) => {
errorsList.push({ title: groupOrTest.title, ...error })
})
return
}

groupOrTest.errors.forEach((error) => {
errorsList.push({ title: groupOrTest.name, ...error })
})
groupOrTest.children.forEach((test) => {
test.errors.forEach((error) => {
errorsList.push({ title: test.title, ...error })
})
})
})
})

await printer.printErrors(errorsList)
`

API

Following are the available methods.

$3

Accepts error as the only argument. If the error is an assertion error, then the diff will be displayed. Otherwise, the error stack is printed.

Assertion diff

`ts
import { Assert } from '@japa/assert'
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()

try {
assert.equal(2 + 2, 5)
} catch (error) {
await printer.printError(error)
}
`

![](assets/assert-error.png)

Jest error

`ts
import expect from 'expect'
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()

try {
expect(2 + 2).toEqual(5)
} catch (error) {
await printer.printError(error)
}
`

![](assets/expect-error.png)

Error stack

`ts
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()
await printer.printError(new Error('boom'))
`

![](assets/fatal-error.png)

$3

Print an array of errors produced by the Japa test runner summary. The method accepts an array of errors in the following format.

`ts
type Error = {
title: string,
phase: string,
error: Error
}
`

`ts
await printer.printErrors([
{
phase: 'test',
title: '2 + 2 = 4'
error: new Error('test failed')
},
{
phase: 'teardown',
title: '2 + 2 = 4'
error: new Error('teardown failed')
}
])
`

$3

Parses the error to JSON using Youch

`ts
import expect from 'expect'
import { ErrorsPrinter } from '@japa/errors-printer'

const printer = new ErrorsPrinter()

try {
expect(2 + 2).toEqual(5)
} catch (error) {
console.log(await printer.parseError(error))
}
`

Output

`ts
{
message: '\x1B[2mexpect(\x1B[22m\x1B[31mreceived\x1B[39m\x1B[2m).\x1B[22mtoEqual\x1B[2m(\x1B[22m\x1B[32mexpected\x1B[39m\x1B[2m) // deep equality\x1B[22m\n' +
'\n' +
'Expected: \x1B[32m5\x1B[39m\n' +
'Received: \x1B[31m4\x1B[39m',
name: 'Error',
frames: [
{
functionName: '',
args: undefined,
fileName: '/Users/virk/code/japa/errors-printer/examples/expect.ts',
lineNumber: 14,
columnNumber: 17,
raw: ' at (/Users/virk/code/japa/errors-printer/examples/expect.ts:14:17)',
type: 'app',
fileType: 'fs',
source: [Array]
},
{
functionName: 'ModuleJob.run',
args: undefined,
fileName: 'node:internal/modules/esm/module_job',
lineNumber: 268,
columnNumber: 25,
raw: ' at ModuleJob.run (node:internal/modules/esm/module_job:268:25)',
type: 'native',
fileType: 'fs',
source: undefined
},
{
functionName: 'async onImport.tracePromise.__proto__',
args: undefined,
fileName: 'node:internal/modules/esm/loader',
lineNumber: 543,
columnNumber: 26,
raw: ' at async onImport.tracePromise.__proto__ (node:internal/modules/esm/loader:543:26)',
type: 'native',
fileType: 'fs',
source: undefined
},
{
functionName: 'async asyncRunEntryPointWithESMLoader',
args: undefined,
fileName: 'node:internal/modules/run_main',
lineNumber: 116,
columnNumber: 5,
raw: ' at async asyncRunEntryPointWithESMLoader (node:internal/modules/run_main:116:5)',
type: 'native',
fileType: 'fs',
source: undefined
}
],
hint: undefined,
code: undefined,
cause: undefined,
stack: 'Error: \x1B[2mexpect(\x1B[22m\x1B[31mreceived\x1B[39m\x1B[2m).\x1B[22mtoEqual\x1B[2m(\x1B[22m\x1B[32mexpected\x1B[39m\x1B[2m) // deep equality\x1B[22m\n' +
'\n' +
'Expected: \x1B[32m5\x1B[39m\n' +
'Received: \x1B[31m4\x1B[39m\n' +
' at (/Users/virk/code/japa/errors-printer/examples/expect.ts:14:17)\n' +
' at ModuleJob.run (node:internal/modules/esm/module_job:268:25)\n' +
' at async onImport.tracePromise.__proto__ (node:internal/modules/esm/loader:543:26)\n' +
' at async asyncRunEntryPointWithESMLoader (node:internal/modules/run_main:116:5)'
}
``

[github-actions-image]: https://img.shields.io/github/actions/workflow/status/japa/errors-printer/checks.yml?style=for-the-badge

[github-actions-url]: https://github.com/japa/errors-printer/actions/workflows/checks.yml "github-actions"

[npm-image]: https://img.shields.io/npm/v/@japa/errors-printer.svg?style=for-the-badge&logo=npm
[npm-url]: https://npmjs.org/package/@japa/errors-printer "npm"

[license-image]: https://img.shields.io/npm/l/@japa/errors-printer?color=blueviolet&style=for-the-badge
[license-url]: LICENSE.md "license"

[typescript-image]: https://img.shields.io/badge/Typescript-294E80.svg?style=for-the-badge&logo=typescript
[typescript-url]: "typescript"