css/css-values/round-function.html

<!doctype html>
<title>round() function</title>
<meta charset=utf-8>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="../support/numeric-testcommon.js"></script>

<meta name=author content="Tab Atkins-Bittner">
<link rel=help href="https://drafts.csswg.org/css-values-4/#round-func">

<div id=target></div>
<script>
// No-op round should be same as nearest
test_math_used("round(23px, 10px)", "20px");
test_math_used("round(18px, 10px)", "20px");
test_math_used("round(15px, 10px)", "20px");
test_math_used("round(13px, 10px)", "10px");
test_math_used("round(-13px, 10px)", "-10px");
test_math_used("round(-18px, 10px)", "-20px");

test_math_used("round(23, 10)", "20", { type: "integer" });
test_math_used("round(18, 10)", "20", { type: "integer" });
test_math_used("round(15, 10)", "20", { type: "integer" });
test_math_used("round(13, 10)", "10", { type: "integer" });
test_math_used("round(-13, 10)", "-10", { type: "integer" });
test_math_used("round(-18, 10)", "-20", { type: "integer" });

// Test nearest
test_math_used("round(nearest, 23px, 10px)", "20px");
test_math_used("round(nearest, 18px, 10px)", "20px");
test_math_used("round(nearest, 15px, 10px)", "20px");
test_math_used("round(nearest, 13px, 10px)", "10px");
test_math_used("round(nearest, -13px, 10px)", "-10px");
test_math_used("round(nearest, -18px, 10px)", "-20px");

test_math_used("round(nearest, 23, 10)", "20", { type: "integer" });
test_math_used("round(nearest, 18, 10)", "20", { type: "integer" });
test_math_used("round(nearest, 15, 10)", "20", { type: "integer" });
test_math_used("round(nearest, 13, 10)", "10", { type: "integer" });
test_math_used("round(nearest, -13, 10)", "-10", { type: "integer" });
test_math_used("round(nearest, -18, 10)", "-20", { type: "integer" });

// Test down
test_math_used("round(down, 23px, 10px)", "20px");
test_math_used("round(down, 18px, 10px)", "10px");
test_math_used("round(down, 15px, 10px)", "10px");
test_math_used("round(down, 13px, 10px)", "10px");
test_math_used("round(down, -13px, 10px)", "-20px");
test_math_used("round(down, -18px, 10px)", "-20px");

test_math_used("round(down, 23, 10)", "20", { type: "integer" });
test_math_used("round(down, 18, 10)", "10", { type: "integer" });
test_math_used("round(down, 15, 10)", "10", { type: "integer" });
test_math_used("round(down, 13, 10)", "10", { type: "integer" });
test_math_used("round(down, -13, 10)", "-20", { type: "integer" });
test_math_used("round(down, -18, 10)", "-20", { type: "integer" });

// Test up
test_math_used("round(up, 23px, 10px)", "30px");
test_math_used("round(up, 18px, 10px)", "20px");
test_math_used("round(up, 15px, 10px)", "20px");
test_math_used("round(up, 13px, 10px)", "20px");
test_math_used("round(up, -13px, 10px)", "-10px");
test_math_used("round(up, -18px, 10px)", "-10px");

test_math_used("round(up, 23, 10)", "30", { type: "integer" });
test_math_used("round(up, 18, 10)", "20", { type: "integer" });
test_math_used("round(up, 15, 10)", "20", { type: "integer" });
test_math_used("round(up, 13, 10)", "20", { type: "integer" });
test_math_used("round(up, -13, 10)", "-10", { type: "integer" });
test_math_used("round(up, -18, 10)", "-10", { type: "integer" });

// Test to-zero
test_math_used("round(to-zero, 23px, 10px)", "20px");
test_math_used("round(to-zero, 18px, 10px)", "10px");
test_math_used("round(to-zero, 15px, 10px)", "10px");
test_math_used("round(to-zero, 13px, 10px)", "10px");
test_math_used("round(to-zero, -13px, 10px)", "-10px");
test_math_used("round(to-zero, -18px, 10px)", "-10px");

test_math_used("round(to-zero, 23, 10)", "20", { type: "integer" });
test_math_used("round(to-zero, 18, 10)", "10", { type: "integer" });
test_math_used("round(to-zero, 15, 10)", "10", { type: "integer" });
test_math_used("round(to-zero, 13, 10)", "10", { type: "integer" });
test_math_used("round(to-zero, -13, 10)", "-10", { type: "integer" });
test_math_used("round(to-zero, -18, 10)", "-10", { type: "integer" });

// Test a negative step
test_math_used("round(23px, -10px)", "20px");
test_math_used("round(18px, -10px)", "20px");
test_math_used("round(15px, -10px)", "20px");
test_math_used("round(13px, -10px)", "10px");
test_math_used("round(-13px, -10px)", "-10px");
test_math_used("round(-18px, -10px)", "-20px");

test_math_used("round(23, -10)", "20", { type: "integer" });
test_math_used("round(18, -10)", "20", { type: "integer" });
test_math_used("round(15, -10)", "20", { type: "integer" });
test_math_used("round(13, -10)", "10", { type: "integer" });
test_math_used("round(-13, -10)", "-10", { type: "integer" });
test_math_used("round(-18, -10)", "-20", { type: "integer" });

// Test with value that is an exact multiple of step
test_math_used("round(10px, 5px)", "10px");
test_math_used("round(nearest, 10px, 5px)", "10px");
test_math_used("round(down, 10px, 5px)", "10px");
test_math_used("round(up, 10px, 5px)", "10px");
test_math_used("round(to-zero, 10px, 5px)", "10px");

test_math_used("round(10, 5)", "10", { type: "integer" });
test_math_used("round(nearest, 10, 5)", "10", { type: "integer" });
test_math_used("round(down, 10, 5)", "10", { type: "integer" });
test_math_used("round(up, 10, 5)", "10", { type: "integer" });
test_math_used("round(to-zero, 10, 5)", "10", { type: "integer" });

test_math_used("round(-10px, 5px)", "-10px");
test_math_used("round(nearest, -10px, 5px)", "-10px");
test_math_used("round(down, -10px, 5px)", "-10px");
test_math_used("round(up, -10px, 5px)", "-10px");
test_math_used("round(to-zero, -10px, 5px)", "-10px");

test_math_used("round(-10, 5)", "-10", { type: "integer" });
test_math_used("round(nearest, -10, 5)", "-10", { type: "integer" });
test_math_used("round(down, -10, 5)", "-10", { type: "integer" });
test_math_used("round(up, -10, 5)", "-10", { type: "integer" });
test_math_used("round(to-zero, -10, 5)", "-10", { type: "integer" });

// Test negation of the round operation
test_math_used("calc(0px - round(23px, 10px))", "-20px");
test_math_used("calc(0px - round(18px, 10px))", "-20px");
test_math_used("calc(0px - round(15px, 10px))", "-20px");
test_math_used("calc(0px - round(13px, 10px))", "-10px");
test_math_used("calc(0px - round(-13px, 10px))", "10px");
test_math_used("calc(0px - round(-18px, 10px))", "20px");

test_math_used("calc(0 - round(23, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(18, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(15, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(13, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(-13, 10))", "10", { type: "integer" });
test_math_used("calc(0 - round(-18, 10))", "20", { type: "integer" });

// Test negation of nearest
test_math_used("calc(0px - round(nearest, 23px, 10px))", "-20px");
test_math_used("calc(0px - round(nearest, 18px, 10px))", "-20px");
test_math_used("calc(0px - round(nearest, 15px, 10px))", "-20px");
test_math_used("calc(0px - round(nearest, 13px, 10px))", "-10px");
test_math_used("calc(0px - round(nearest, -13px, 10px))", "10px");
test_math_used("calc(0px - round(nearest, -18px, 10px))", "20px");

test_math_used("calc(0 - round(nearest, 23, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(nearest, 18, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(nearest, 15, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(nearest, 13, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(nearest, -13, 10))", "10", { type: "integer" });
test_math_used("calc(0 - round(nearest, -18, 10))", "20", { type: "integer" });

// Test negation of down
test_math_used("calc(0px - round(down, 23px, 10px))", "-20px");
test_math_used("calc(0px - round(down, 18px, 10px))", "-10px");
test_math_used("calc(0px - round(down, 15px, 10px))", "-10px");
test_math_used("calc(0px - round(down, 13px, 10px))", "-10px");
test_math_used("calc(0px - round(down, -13px, 10px))", "20px");
test_math_used("calc(0px - round(down, -18px, 10px))", "20px");

test_math_used("calc(0 - round(down, 23, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(down, 18, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(down, 15, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(down, 13, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(down, -13, 10))", "20", { type: "integer" });
test_math_used("calc(0 - round(down, -18, 10))", "20", { type: "integer" });

// Test negation of up
test_math_used("calc(0px - round(up, 23px, 10px))", "-30px");
test_math_used("calc(0px - round(up, 18px, 10px))", "-20px");
test_math_used("calc(0px - round(up, 15px, 10px))", "-20px");
test_math_used("calc(0px - round(up, 13px, 10px))", "-20px");
test_math_used("calc(0px - round(up, -13px, 10px))", "10px");
test_math_used("calc(0px - round(up, -18px, 10px))", "10px");

test_math_used("calc(0 - round(up, 23, 10))", "-30", { type: "integer" });
test_math_used("calc(0 - round(up, 18, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(up, 15, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(up, 13, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(up, -13, 10))", "10", { type: "integer" });
test_math_used("calc(0 - round(up, -18, 10))", "10", { type: "integer" });

// Test negation of to-zero
test_math_used("calc(0px - round(to-zero, 23px, 10px))", "-20px");
test_math_used("calc(0px - round(to-zero, 18px, 10px))", "-10px");
test_math_used("calc(0px - round(to-zero, 15px, 10px))", "-10px");
test_math_used("calc(0px - round(to-zero, 13px, 10px))", "-10px");
test_math_used("calc(0px - round(to-zero, -13px, 10px))", "10px");
test_math_used("calc(0px - round(to-zero, -18px, 10px))", "10px");

test_math_used("calc(0 - round(to-zero, 23, 10))", "-20", { type: "integer" });
test_math_used("calc(0 - round(to-zero, 18, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(to-zero, 15, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(to-zero, 13, 10))", "-10", { type: "integer" });
test_math_used("calc(0 - round(to-zero, -13, 10))", "10", { type: "integer" });
test_math_used("calc(0 - round(to-zero, -18, 10))", "10", { type: "integer" });

// Test omission of <step> argument
test_math_used("round(1.5)", "2", { type: "integer" });
test_math_used("round(up, 1.5)", "2", { type: "integer" });
test_math_used("round(down, 1.5)", "1", { type: "integer" });
test_math_used("round(to-zero, 1.5)", "1", { type: "integer" });
test_math_used("round(-1.5)", "-1", { type: "integer" });
test_math_used("round(up, -1.5)", "-1", { type: "integer" });
test_math_used("round(down, -1.5)", "-2", { type: "integer" });
test_math_used("round(to-zero, -1.5)", "-1", { type: "integer" });

// Extreme cases:

// 0 step is NaN
test_nan("round(5, 0)");
// both infinite is NaN
test_nan("round(infinity, infinity)");
test_nan("round(infinity, -infinity)");
test_nan("round(-infinity, infinity)");
test_nan("round(-infinity, -infinity)");
// NaN is infectious.
// https://drafts.csswg.org/css-values-4/#calc-ieee
test_nan("round(NaN, 5)");
test_nan("round(NaN, -5)");
test_nan("round(NaN, 0)");
test_nan("round(NaN, infinity)");
test_nan("round(NaN, -infinity)");
test_nan("round(5, NaN)");
test_nan("round(-5, NaN)");
test_nan("round(0, NaN)");
test_nan("round(infinity, NaN)");
test_nan("round(NaN, NaN)");
test_nan("round(nearest, NaN, 5)");
test_nan("round(up, NaN, 5)");
test_nan("round(down, NaN, 5)");
test_nan("round(to-zero, NaN, 5)");

// infinite value with finite step is the same infinity
test_plus_infinity("round(infinity, 5)");
test_plus_infinity("round(infinity, -5)");
test_minus_infinity("round(-infinity, 5)");
test_minus_infinity("round(-infinity, -5)");

// Finite value with infinite step depends on rounding strategy.
// 'nearest' and 'to-zero': pos and +0 go to +0, neg and -0 go to -0
test_plus_zero("round(5, infinity)");
test_plus_zero("round(5, -infinity)");
test_minus_zero("round(-5, infinity)");
test_minus_zero("round(-5, -infinity)");
test_plus_zero("round(to-zero, 5, infinity)");
test_plus_zero("round(to-zero, 5, -infinity)");
test_minus_zero("round(to-zero, -5, infinity)");
test_minus_zero("round(to-zero, -5, -infinity)");
// 'up': pos goes to +inf, 0+ goes to 0+, else 0-
test_plus_infinity("round(up, 1, infinity)");
test_plus_zero("round(up, 0, infinity)");
test_minus_zero("round(up, -1 * 0, infinity)");
test_minus_zero("round(up, -1, infinity)");
// 'down': neg goes to -inf, -0 goes to -0, else 0+
test_minus_infinity("round(down, -1, infinity)");
test_minus_zero("round(down, -1 * 0, infinity)");
test_plus_zero("round(down, 0, infinity)");
test_plus_zero("round(down, 1, infinity)");

// In this test if the multiplication is factored into the sum first, the
// result of the round will be incorrect, because of floating point inprecision.
// round(down, 2.3333333 - 0.33333334, 1) = round(down, 1.99999996, 1) = 1
test_math_used('round(down, (7 - 1) / 3, 1)', '2', {type:'number'});
</script>