<script>
function waitForColorSchemeToBe(scheme) {
return new Promise(resolve => {
let mq = matchMedia(`(prefers-color-scheme: ${scheme})`);
if (mq.matches) {
resolve();
} else {
mq.addEventListener("change", resolve, { once: true });
}
});
}
add_setup(async function() {
// Set a dark color scheme so that we can properly test the print override.
await SpecialPowers.pushPrefEnv({ set: [["layout.css.prefers-color-scheme.content-override", 0]] });
await waitForColorSchemeToBe("dark");
});
let originalColor = 'rgb(0, 128, 0)';
let body = document.body;
let getColor = function() {
return window.getComputedStyle(body).backgroundColor;
};
for (let test of tests) {
// Emulate the given media
SpecialPowers.emulateMedium(window, test.name);
is(getColor(), test.value, 'emulating ' + test.name + ' produced ' + 'correct rendering');
ok(matchMedia(test.name).matches, "Media matches");
if (test.value == "print") {
ok(matchMedia("(prefers-color-scheme: light)").matches, "color-scheme is overridden when emulating print");
}
// Do the @media screen rules get applied after ending the emulation?
SpecialPowers.stopEmulatingMedium(window);
is(getColor(), originalColor, 'Ending ' + test.name + ' emulation restores style for original medium');
ok(!matchMedia(test.name).matches, "Media no longer matches");
ok(!matchMedia("(prefers-color-scheme: light)").matches, "color-scheme override should be restored");
// CSS media types are case-insensitive; we should be too.
SpecialPowers.emulateMedium(window, test.name.toUpperCase());
is(getColor(), test.value,
test.name + ' emulation is case-insensitive');
SpecialPowers.stopEmulatingMedium(window);
}
is(getColor(), originalColor, 'No emulation');
// Emulating screen should produce the same rendering as when there is
// no emulation in effect
SpecialPowers.emulateMedium(window, 'screen');
is(getColor(), originalColor, 'Emulating screen produces original rendering');
SpecialPowers.stopEmulatingMedium(window);
// Screen should be case-insensitive too
SpecialPowers.emulateMedium(window, 'SCREEN');
is(getColor(), originalColor, 'screen emulation is case-insensitive');
SpecialPowers.stopEmulatingMedium(window);
// An invalid parameter shouldn't fail. Given the CSS rules above,
// an invalid parameter should result in a different rendering from any
// produced thus far
SpecialPowers.emulateMedium(window, 'clay');
let invalid = getColor();
tests.push({name: 'screen', value: 'green'});
tests.forEach(function(test) {
isnot(invalid, test.value, 'Emulating invalid type differs from ' +
test.name);
});
¤ Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.0.4Bemerkung:
¤
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung und die Messung sind noch experimentell.