yanchengPowerSupply/node_modules/es5-shim/tests/spec/s-number.js

104 lines
4.0 KiB
JavaScript

describe('Number', function () {
'use strict';
describe('#toExponential()', function () {
// the spec allows for this test to fail.
it('throws a RangeError when < 0 or > 20 (or > 100 in ES2018+)', function () {
expect(function () { return 1.0.toExponential(-1); }).toThrow();
expect(function () { return 1.0.toExponential(-Infinity); }).toThrow();
expect(function () { return 1.0.toExponential(Infinity); }).toThrow();
expect(function () {
return [
(0.9).toExponential(21), // ES2018 increased the limit from 21 to 100
(0.9).toExponential(101)
];
}).toThrow();
});
it('works for NaN receiver', function () {
expect(NaN.toExponential(NaN)).toBe('NaN');
expect(NaN.toExponential('abc')).toBe('NaN');
});
it('works for non-finite receivers', function () {
expect(Infinity.toExponential()).toBe('Infinity');
expect((-Infinity).toExponential()).toBe('-Infinity');
});
it('should round properly', function () {
expect(1.0.toExponential()).toBe('1e+0');
expect(1.0.toExponential(0)).toBe('1e+0');
expect(1.0.toExponential(1)).toBe('1.0e+0');
expect(1.0.toExponential(2)).toBe('1.00e+0');
expect(1.2345.toExponential()).toBe('1.2345e+0');
expect(1.2345.toExponential(0)).toBe('1e+0');
expect(1.2345.toExponential(1)).toBe('1.2e+0');
expect(1.2345.toExponential(2)).toBe('1.23e+0');
expect(1.2345.toExponential(3)).toMatch(/^1.23[45]e\+0$/);
expect(1.2345.toExponential(4)).toBe('1.2345e+0');
expect(1.2345.toExponential(5)).toBe('1.23450e+0');
expect((-6.9e-11).toExponential(4)).toBe('-6.9000e-11');
});
});
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 (or > 100 in ES2018+)', function () {
expect(function () { return (0.9).toPrecision(0); }).toThrow();
expect(function () {
return [
(0.9).toPrecision(22), // ES2018 increased the limit from 21 to 100
(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);
});
});
});