layout/style/test/test_units_length.html

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<head>
  <title>Test for serialization and equivalence of length units</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
</head>
<body>
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=">Mozilla Bug </a>
<p id="display"></p>
<div id="content" style="display: none">
  
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<pre id="test">
<script type="application/javascript">

/** Test for serialization and equivalence of length units **/

/**
 * We test that for each of the following:
 *  + they reserialize to exactly what is given
 *  + if a mapping is provided, they compute to the same result as the mapping
 */
var tests = {
  "1in": "72pt",
  "20mm": "2cm",
  "2.54cm": "1in",
  "36pt": "0.5in",
  "4pc": "48pt",
  "1em": null,
  "3ex": null,
  "57px": null,
  "5rem": null
};

var p = document.getElementById("display");

for (var test in tests) {
  p.setAttribute("style", "margin-left: " + test);
  is(p.style.getPropertyValue("margin-left"), test,
     test + " serializes to exactly itself");
  var equiv = tests[test];
  if (equiv) {
    var cm1 = getComputedStyle(p, "").marginLeft;
    p.style.marginLeft = equiv;
    var cm2 = getComputedStyle(p, "").marginLeft;

    ok(Math.abs(parseFloat(cm1, 10) - parseFloat(cm2, 10)) <= 0.0001, test + " should compute to the same as " + equiv + ", modulo floating point math error");
  }
}

// Bug 393910
p.setAttribute("style", "margin-left: 0");
is(p.style.getPropertyValue("margin-left"), "0px",
  "0 serializes to 0px");

</script>
</pre>
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