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Test Info:
"use strict";
const { Color } = ChromeUtils.importESModule(
"resource://gre/modules/Color.sys.mjs"
);
function run_test() {
testRelativeLuminance();
testUseBrightText();
testContrastRatio();
testIsContrastRatioAcceptable();
}
function testRelativeLuminance() {
let c = new Color(0, 0, 0);
Assert.equal(c.relativeLuminance, 0, "Black is not illuminating");
c = new Color(255, 255, 255);
Assert.equal(c.relativeLuminance, 1, "White is quite the luminant one");
c = new Color(142, 42, 142);
Assert.equal(
c.relativeLuminance,
0.09359705837110571,
"This purple is not that luminant"
);
}
function testUseBrightText() {
let c = new Color(0, 0, 0);
Assert.ok(
c.useBrightText,
"Black is bright, so bright text should be used here"
);
c = new Color(255, 255, 255);
Assert.ok(
!c.useBrightText,
"White is bright, so better not use bright colored text on it"
);
}
function testContrastRatio() {
let c = new Color(0, 0, 0);
let c2 = new Color(255, 255, 255);
Assert.equal(
c.contrastRatio(c2),
21,
"Contrast between black and white is max"
);
Assert.equal(c.contrastRatio(c), 1, "Contrast between equals is min");
let c3 = new Color(142, 42, 142);
Assert.equal(
c.contrastRatio(c3),
2.871941167422114,
"Contrast between black and purple shouldn't be very high"
);
Assert.equal(
c2.contrastRatio(c3),
7.312127503938331,
"Contrast between white and purple should be high"
);
}
function testIsContrastRatioAcceptable() {
// Let's assert what browser.js is doing for window frames.
let c = new Color(...[55, 156, 152]);
let c2 = new Color(0, 0, 0);
Assert.equal(c.r, 55, "Reds should match");
Assert.equal(c.g, 156, "Greens should match");
Assert.equal(c.b, 152, "Blues should match");
Assert.ok(
c.isContrastRatioAcceptable(c2),
"The blue is high contrast enough"
);
c2 = new Color(...[35, 65, 100]);
Assert.ok(
!c.isContrastRatioAcceptable(c2),
"The blue is not high contrast enough"
);
// But would it be high contrast enough at a lower conformance level?
Assert.ok(
c.isContrastRatioAcceptable(c2, "A"),
"The blue is high contrast enough when used as large text"
);
}