create-new-app
Version:
Easily generate a new React application, optionally with Express & MongoDB.
41 lines (35 loc) • 1.21 kB
JavaScript
/*
http://bit.ly/2Whx6xi - extending `expect` for Jest.
In the end-to-end tests we want to ensure that the correct versions
of packages were installed. Since we know what major version we're
trying to install, we need a way to compare the beginning of the packages
with each other.
http://bit.ly/2WgsNCy - using the `jest` key in our `package.json` file,
we point to this file in the `setupFilesAfterEnv` property. Anything added
to this file will be executed after the test environment has been set up
but before any of the tests have run.
*/
expect.extend({
toStartWith(received, expected, meta) {
const pass = typeof received === 'string' && received.startsWith(expected)
const extra = meta ? ` (${meta})` : ''
if (pass) {
return {
message: () => {
return `expected ${received} not to start with ${expected}${extra}`
},
pass: true,
}
}
return {
message: () => {
if (typeof received !== 'string') {
return `expected a string but received ${received}`
} else {
return `expected ${received} to start with ${expected}${extra}`
}
},
pass: false,
}
},
})