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function mod(a, b) {
return a % b;
}
var cases = [
// Zero remainder takes the sign of the dividend.
[6, 3, 0],
[-6, 3, -0],
[6, -3, 0],
[-6, -3, -0],
[0, 5, 0],
[-0, 5, -0],
// x % -1 is always zero, with the sign of x.
[2147483647, -1, 0],
[-2147483648, -1, -0],
[5, -1, 0],
[-5, -1, -0],
// Non-zero remainders carry the sign of the dividend.
[7, 3, 1],
[-7, 3, -1],
[7, -3, 1],
[-7, -3, -1],
[-2147483648, 3, -2],
[-2147483648, 2147483647, -1],
// Int32 -> NUMBER_MAX
[2147483648, -1, 0],
[-2147483648, -2147483648, -0],
[2 ** 53 - 1, 3, 1],
[2147483648, 3, 2],
[-2147483649, 3, -0],
[-2147483650, 3, -1],
[4294967296, 2147483647, 2],
[2 ** 53, 3, 2],
[-(2 ** 53), 3, -2],
[2 ** 53 - 1, 2 ** 53 - 2, 1],
// INT64_MIN and its neighbourhood.
[-(2 ** 63), -1, -0],
[-(2 ** 63), 3, -2],
[-(2 ** 63), 2 ** 62, -0],
[-(2 ** 63), -(2 ** 63), -0],
[2 ** 62, -(2 ** 63), 2 ** 62],
// Out of the fast path
[2 ** 63, -1, 0],
[2 ** 63, 3, 2],
[2 ** 63, 2 ** 62, 0],
[-(2 ** 64), 3, -1],
[2 ** 64, -(2 ** 63), 0],
[1e300, 3, 0],
[1e300, 7, 1],
// Only one operand out of range still leaves the fast path.
[2 ** 63, 7, 1],
[7, 2 ** 63, 7],
[-7, 2 ** 63, -7],
// Non-integer operands fall back to fmod.
[9.5, -5, 4.5],
[-9.5, 5, -4.5],
// Non-finite operands.
[Infinity, 3, NaN],
[5, Infinity, 5],
[NaN, 3, NaN],
[5, NaN, NaN],
];
function test() {
for (var i = 0; i < cases.length; i++) {
var a = cases[i][0];
var b = cases[i][1];
var expected = cases[i][2];
assertEq(mod(a, b), expected, `mod(${a}, ${b}) != ${expected}`);
}
// b == 0 always yields NaN regardless of the dividend.
assertEq(mod(5, 0), NaN);
assertEq(mod(-5, 0), NaN);
assertEq(mod(0, 0), NaN);
assertEq(mod(5, -0), NaN);
}
for (var iter = 0; iter < 200; iter++) {
test();
}