function expectRejection()

in spec/helpers.js [48:63]

• 16 lines of code
• 4 McCabe index (conditional complexity)

function expectRejection (promise, expectedReason) {
    return promise.then(
        () => fail('Expected promise to be rejected'),
        reason => {
            if (expectedReason instanceof Error) {
                expect(reason instanceof expectedReason.constructor).toBeTruthy();
                expect(reason.message).toContain(expectedReason.message);
            } else if (typeof expectedReason === 'function') {
                expect(expectedReason(reason)).toBeTruthy();
            } else if (expectedReason !== undefined) {
                expect(reason).toBe(expectedReason);
            } else {
                expect().nothing();
            }
        });
}