amazon-cognito-identity-js/__tests__/cryptoSecureRandomInt.test.js

Amazon Cognito Identity Provider JavaScript SDK

const crypto = require('crypto');

jest.mock('crypto', () => ({
	getRandomValues: jest.fn(),
	randomBytes: jest.fn(() => ({
		readInt32LE: jest.fn().mockReturnValueOnce(54321),
	})),
}));

describe('cryptoSecureRandomInt test', () => {
	let windowSpy;

	beforeEach(() => {
		jest.resetModules();
		windowSpy = jest.spyOn(window, 'window', 'get');
	});

	afterEach(() => {
		windowSpy.mockRestore();
	});

	test('crypto is set for window (browser)', () => {
		windowSpy.mockImplementation(() => ({
			crypto: {
				getRandomValues: () => [12345],
			},
		}));

		const cryptoSecureRandomInt =
			require('../src/utils/cryptoSecureRandomInt').default;
		expect(window.crypto).toBeTruthy();
		expect(cryptoSecureRandomInt()).toBe(12345);
	});

	test('crypto is set for window (IE 11)', () => {
		windowSpy.mockImplementation(() => ({
			crypto: undefined,
			msCrypto: {
				getRandomValues: () => [67890],
			},
		}));

		const cryptoSecureRandomInt =
			require('../src/utils/cryptoSecureRandomInt').default;
		expect(window.msCrypto).toBeTruthy();
		expect(cryptoSecureRandomInt()).toBe(67890);
	});

	test('crypto is set for Node (< 18)', () => {
		windowSpy.mockImplementationOnce(() => ({
			crypto: null,
		}));

		const savedGlobalCrypto = globalThis.crypto;
		Object.defineProperty(globalThis, 'crypto', {
			value: undefined,
			configurable: true,
			writable: true,
		});
		try {
			const currentMockCrypto = require('crypto');
			currentMockCrypto.getRandomValues = undefined;

			const cryptoSecureRandomInt =
				require('../src/utils/cryptoSecureRandomInt').default;
			expect(cryptoSecureRandomInt()).toBe(54321);
		} finally {
			Object.defineProperty(globalThis, 'crypto', {
				value: savedGlobalCrypto,
				configurable: true,
				writable: true,
			});
		}
	});

	test('crypto is set for Node (>= 18)', () => {
		windowSpy.mockImplementationOnce(() => ({
			crypto: null,
		}));

		const savedGlobalCrypto = globalThis.crypto;
		Object.defineProperty(globalThis, 'crypto', {
			value: undefined,
			configurable: true,
			writable: true,
		});
		try {
			const currentMockCrypto = require('crypto');
			currentMockCrypto.getRandomValues.mockReturnValueOnce([54321]);

			const cryptoSecureRandomInt =
				require('../src/utils/cryptoSecureRandomInt').default;
			expect(cryptoSecureRandomInt()).toBe(54321);
		} finally {
			Object.defineProperty(globalThis, 'crypto', {
				value: savedGlobalCrypto,
				configurable: true,
				writable: true,
			});
		}
	});
});