mirror of
https://github.com/RGBCube/serenity
synced 2025-10-31 15:12:45 +00:00
36 lines
1.2 KiB
JavaScript
36 lines
1.2 KiB
JavaScript
function isPositiveZero(value) {
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return value === 0 && 1 / value === Infinity;
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}
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function isNegativeZero(value) {
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return value === 0 && 1 / value === -Infinity;
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}
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test("basic functionality", () => {
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expect(Math.sign).toHaveLength(1);
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expect(Math.sign(0.0001)).toBe(1);
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expect(Math.sign(1)).toBe(1);
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expect(Math.sign(42)).toBe(1);
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expect(Math.sign(Infinity)).toBe(1);
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expect(isPositiveZero(Math.sign(0))).toBeTrue();
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expect(isPositiveZero(Math.sign(null))).toBeTrue();
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expect(isPositiveZero(Math.sign(""))).toBeTrue();
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expect(isPositiveZero(Math.sign([]))).toBeTrue();
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expect(Math.sign(-0.0001)).toBe(-1);
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expect(Math.sign(-1)).toBe(-1);
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expect(Math.sign(-42)).toBe(-1);
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expect(Math.sign(-Infinity)).toBe(-1);
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expect(isNegativeZero(Math.sign(-0))).toBeTrue();
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expect(isNegativeZero(Math.sign(-null))).toBeTrue();
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expect(isNegativeZero(Math.sign(-""))).toBeTrue();
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expect(isNegativeZero(Math.sign(-[]))).toBeTrue();
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expect(Math.sign()).toBeNaN();
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expect(Math.sign(undefined)).toBeNaN();
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expect(Math.sign([1, 2, 3])).toBeNaN();
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expect(Math.sign({})).toBeNaN();
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expect(Math.sign(NaN)).toBeNaN();
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expect(Math.sign("foo")).toBeNaN();
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});
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