react/scripts/jest/matchers/reactTestMatchers.js

48 lines
1.3 KiB
JavaScript

'use strict';
const JestReact = require('jest-react');
// TODO: Move to ReactInternalTestUtils
function captureAssertion(fn) {
// Trick to use a Jest matcher inside another Jest matcher. `fn` contains an
// assertion; if it throws, we capture the error and return it, so the stack
// trace presented to the user points to the original assertion in the
// test file.
try {
fn();
} catch (error) {
return {
pass: false,
message: () => error.message,
};
}
return {pass: true};
}
function assertYieldsWereCleared(Scheduler, caller) {
const actualYields = Scheduler.unstable_clearLog();
if (actualYields.length !== 0) {
const error = Error(
'The event log is not empty. Call assertLog(...) first.'
);
Error.captureStackTrace(error, caller);
throw error;
}
}
function toMatchRenderedOutput(ReactNoop, expectedJSX) {
if (typeof ReactNoop.getChildrenAsJSX === 'function') {
const Scheduler = ReactNoop._Scheduler;
assertYieldsWereCleared(Scheduler, toMatchRenderedOutput);
return captureAssertion(() => {
expect(ReactNoop.getChildrenAsJSX()).toEqual(expectedJSX);
});
}
return JestReact.unstable_toMatchRenderedOutput(ReactNoop, expectedJSX);
}
module.exports = {
toMatchRenderedOutput,
};