LibJS: Add spec comments and check for edge cases in Math.log10

This commit is contained in:
davidot 2022-11-28 12:06:50 +01:00 committed by Andreas Kling
parent eda90b54d4
commit 4306462a95
Notes: sideshowbarker 2024-07-17 03:59:11 +09:00
2 changed files with 23 additions and 3 deletions

View file

@ -574,10 +574,27 @@ JS_DEFINE_NATIVE_FUNCTION(MathObject::log2)
// 21.3.2.22 Math.log10 ( x ), https://tc39.es/ecma262/#sec-math.log10
JS_DEFINE_NATIVE_FUNCTION(MathObject::log10)
{
auto value = TRY(vm.argument(0).to_number(vm)).as_double();
if (value < 0)
// 1. Let n be ? ToNumber(x).
auto number = TRY(vm.argument(0).to_number(vm));
// 2. If n is NaN or n is +∞𝔽, return n.
if (number.is_nan() || number.is_positive_infinity())
return number;
// 3. If n is 1𝔽, return +0𝔽.
if (number.as_double() == 1.)
return Value(0);
// 4. If n is +0𝔽 or n is -0𝔽, return -∞𝔽.
if (number.is_positive_zero() || number.is_negative_zero())
return js_negative_infinity();
// 5. If n < -0𝔽, return NaN.
if (number.as_double() < -0.)
return js_nan();
return Value(::log10(value));
// 6. Return an implementation-approximated Number value representing the result of the base 10 logarithm of (n).
return Value(::log10(number.as_double()));
}
// 21.3.2.31 Math.sinh ( x ), https://tc39.es/ecma262/#sec-math.sinh

View file

@ -6,4 +6,7 @@ test("basic functionality", () => {
expect(Math.log10(0)).toBe(-Infinity);
expect(Math.log10(-2)).toBe(NaN);
expect(Math.log10(100000)).toBe(5);
expect(Math.log10(NaN)).toBe(NaN);
expect(Math.log10(Number.POSITIVE_INFINITY)).toBe(Number.POSITIVE_INFINITY);
expect(Math.log10(-0.0)).toBe(Number.NEGATIVE_INFINITY);
});