2a09d1a4
 liuqimichale
添加宜春 天水 宣化
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/* global describe, it, expect */
describe('Number', function () {
'use strict';
describe('#toFixed()', function () {
it('should convert numbers correctly', function () {
expect((0.00008).toFixed(3)).toBe('0.000');
expect((0.9).toFixed(0)).toBe('1');
expect((1.255).toFixed(2)).toBe('1.25');
expect((1843654265.0774949).toFixed(5)).toBe('1843654265.07749');
expect((1000000000000000128).toFixed(0)).toBe('1000000000000000128');
});
});
describe('#toPrecision()', function () {
// the spec allows for this test to fail.
it('throws a RangeError when < 1 or > 21', function () {
expect(function () { return (0.9).toPrecision(0); }).toThrow();
// Firefox allows values up to 100
expect(function () { return (0.9).toPrecision(101); }).toThrow();
});
it('works as expected', function () {
expect((0.00008).toPrecision(3)).toBe('0.0000800');
expect((1.255).toPrecision(2)).toBe('1.3');
expect((1843654265.0774949).toPrecision(13)).toBe('1843654265.077');
expect(NaN.toPrecision(1)).toBe('NaN');
});
it('works with an undefined precision', function () {
var num = 123.456;
expect(num.toPrecision()).toBe(String(num));
expect(num.toPrecision(undefined)).toBe(String(num));
});
});
describe('constants', function () {
it('should have MAX_VALUE', function () {
expect(Number.MAX_VALUE).toBe(1.7976931348623157e308);
});
it('should have MIN_VALUE', function () {
expect(Number.MIN_VALUE).toBe(5e-324);
});
it('should have NaN', function () {
expect(Number.NaN).not.toBe(Number.NaN);
});
it('should have POSITIVE_INFINITY', function () {
expect(Number.POSITIVE_INFINITY).toBe(Infinity);
});
it('should have NEGATIVE_INFINITY', function () {
expect(Number.NEGATIVE_INFINITY).toBe(-Infinity);
});
});
});
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