Files
30-seconds-of-code/test/deepFreeze.test.js
2018-10-19 20:18:00 +03:00

36 lines
748 B
JavaScript

const expect = require('expect');
const {deepFreeze} = require('./_30s.js');
test('deepFreeze is a Function', () => {
expect(deepFreeze).toBeInstanceOf(Function);
});
test('modifying deeply freezed object prop throws an error in strict mode', () => {
let freezedObj = deepFreeze({ a: 42 });
expect(() => {
'use strict';
freezedObj.a = 24;
}).toThrow();
});
test('should not modify deeply freezed object inside another object', () => {
let freezedObj = deepFreeze({
a: {
b: 42
}
});
freezedObj.a.b = 16;
expect(freezedObj.a.b).toBe(42);
});
test('should not add prop to deeply freezed empty object', () => {
let freezedObj = deepFreeze({});
freezedObj.a = 42;
expect(freezedObj).toEqual({});
});