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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /css/css-text/tab-size/tab-size.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<meta charset="utf-8">
<title>Test: CSS value type of the CSS property 'tab-size'</title>
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style>
body {
font-family: Ahem;
font-size: 13px;
}
.px-tab-size {
tab-size: 60px;
}
.em-tab-size {
tab-size: 7em;
}
.int-tab-size {
tab-size: 9;
}
.fractional-tab-size {
tab-size: 2.5;
}
</style>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<div style="background-repeat: repeat-x;">
<div><pre id="leading-px" class="px-tab-size">	<span>leading text, tab-size in px.</span></pre></div>
<div><pre id="leading-em" class="em-tab-size">	<span>leading text, tab-size in em.</span></pre></div>
<div><pre id="leading-int" class="int-tab-size">	<span>leading text, tab-size in spaces.</span></pre></div>
<div><pre id="leading-fraction" class="fractional-tab-size">	<span>leading text, tab-size in fraction.</span></pre></div>
<div><pre id="trailing-px" class="px-tab-size"><span>leading text</span>	<span>trailing text, tab-size in px.</span></pre></div>
<div><pre id="trailing-em" class="em-tab-size"><span>leading text</span>	<span>trailing text, tab-size in em.</span></pre></div>
<div><pre id="trailing-int" class="int-tab-size"><span>leading text</span>	<span>trailing text, tab-size in spaces.</span></pre></div>
<div><pre id="trailing-fraction" class="fractional-tab-size"><span>leading text</span>	<span>trailing text, tab-size in fraction.</span></pre></div>
<div><pre>Some spaces... '<span id="space-size-reference"> </span>' ... for size reference.</pre></div>
<div><pre>A space... '<span id="one-space-size-reference"> </span>' ... for size reference.</pre></div>
<div><pre>'<span id="leading-text-size-reference">leading text</span>', for size reference.</pre></div>
<script>
test(function() {
// Tests with a tab character at the beginning of the line.
var pxPre = document.getElementById('leading-px');
var emPre = document.getElementById('leading-em');
var intPre = document.getElementById('leading-int');
var fractionPre = document.getElementById("leading-fraction");
var pxLeadingSpan = pxPre.firstElementChild;
var emLeadingSpan = emPre.firstElementChild;
var intLeadingSpan = intPre.firstElementChild;
var fractionLeadingspan = fractionPre.firstElementChild;
var pxExpected = 60; // tab size in px.
var emExpected = 13 * 7; // (font size) * (tab size in em)
var intExpected = document.getElementById('space-size-reference').getBoundingClientRect().width;
var fractionExpected = 2.5 * document.getElementById('one-space-size-reference').getBoundingClientRect().width;
var pxTabLength = pxLeadingSpan.getBoundingClientRect().left - pxPre.getBoundingClientRect().left;
var emTabLength = emLeadingSpan.getBoundingClientRect().left - emPre.getBoundingClientRect().left;
var intTabLength = intLeadingSpan.getBoundingClientRect().left - intPre.getBoundingClientRect().left;
var fractionTabLength = fractionLeadingspan.getBoundingClientRect().left - fractionPre.getBoundingClientRect().left;
assert_approx_equals(pxTabLength, pxExpected, 0.02);
assert_approx_equals(emTabLength, emExpected, 0.02);
assert_approx_equals(intTabLength, intExpected, 0.02);
assert_approx_equals(fractionTabLength, fractionExpected, 0.02);
// Tests with a tab character after leading text.
var leadingTextSize = document.getElementById('leading-text-size-reference').getBoundingClientRect().width;
pxExpected = pxExpected - (leadingTextSize % pxExpected);
emExpected = emExpected - (leadingTextSize % emExpected);
intExpected = intExpected - (leadingTextSize % intExpected);
fractionExpected = fractionExpected - (leadingTextSize % fractionExpected);
pxPre = document.getElementById('trailing-px');
emPre = document.getElementById('trailing-em');
intPre = document.getElementById('trailing-int');
fractionPre = document.getElementById("trailing-fraction");
pxLeadingSpan = pxPre.firstElementChild;
emLeadingSpan = emPre.firstElementChild;
intLeadingSpan = intPre.firstElementChild;
fractionLeadingspan = fractionPre.firstElementChild;
pxTrailingSpan = pxPre.lastElementChild;
emTrailingSpan = emPre.lastElementChild;
intTrailingSpan = intPre.lastElementChild;
fractionTrailingSpan = fractionPre.lastElementChild;
pxTabLength = pxTrailingSpan.getBoundingClientRect().left - pxLeadingSpan.getBoundingClientRect().right;
emTabLength = emTrailingSpan.getBoundingClientRect().left - emLeadingSpan.getBoundingClientRect().right;
intTabLength = intTrailingSpan.getBoundingClientRect().left - intLeadingSpan.getBoundingClientRect().right;
fractionTabLength = fractionTrailingSpan.getBoundingClientRect().left - fractionLeadingspan.getBoundingClientRect().right;
assert_approx_equals(pxTabLength, pxExpected, 0.02);
assert_approx_equals(emTabLength, emExpected, 0.02);
assert_approx_equals(intTabLength, intExpected, 0.02);
assert_approx_equals(fractionTabLength, fractionExpected, 0.02);
}, "Test tab-size measurements");
</script>