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- This WPT test may be referenced by the following Test IDs:
- /css/css-values/getComputedStyle-calc-mixed-units-001.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<meta charset="UTF-8">
<title>CSS Values Test: computed value of 3 calc() values</title>
<!--
"
Where percentages are not resolved at computed-value time,
they are not resolved in math functions, e.g.
'calc(100% - 100% + 1px)' resolves to 'calc(0% + 1px)', not to
'1px'. If there are special rules for computing percentages
in a value (e.g. the 'height' property), they apply whenever
a math function contains percentages.
"
§ 10.11 Computed Value
-->
<link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
<meta name="flags" content="">
<meta content="This test verifies that terms with a percentage unit that can not be resolved at computed-value time will require a calc() wrapper. A term with an em value, on the other hand, must be resolved at computed-value time and therefore must be absolutized to 'px'." name="assert">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
html, body
{
font-size: 16px;
height: 570px;
}
div#target
{
background-color: yellow;
background-image: url("support/cat.png");
background-position: top center;
background-repeat: no-repeat;
background-size: 14% 50%; /* entirely arbitrary and random background-size values */
height: 200px;
}
</style>
<div id="target"></div>
<script>
function startTesting()
{
var targetElement = document.getElementById("target");
function verifyComputedStyle(property_name, specified_value, expected_value)
{
test(function()
{
targetElement.style.setProperty(property_name, specified_value);
assert_equals(getComputedStyle(targetElement)[property_name], expected_value);
}, `testing ${property_name}: ${specified_value}`);
}
verifyComputedStyle("background-size", "calc(67% - 54% + 4em) 50%", "calc(13% + 64px) 50%");
/*
"Where percentages are not resolved at computed-value time,
they are not resolved in math functions (...)"
Therefore here, the percentage is preserved and
a calc() wrapper must be used. The 4em term
must be resolved though.
*/
verifyComputedStyle("background-position", "calc(100% - 100% + 20em)", "calc(0% + 320px) 50%");
/*
Here too, the percentage is preserved and
a calc() wrapper must be used. The 20em term
must be resolved though.
*/
verifyComputedStyle("height", "calc(60% - 50% + 3em)", "105px");
/*
The height of the containing block of div#target is not auto.
So, such percentage can and must be resolved at
computed-value time.
570px mult 10% == 57px
+ 48px
============
105px
*/
}
startTesting();
</script>