<!DOCTYPE html>
<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
<title>Canvas test: 2d.text.drawing.style.letterSpacing.measure</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/html/canvas/resources/canvas-tests.js"></script>
<link rel="stylesheet" href="/html/canvas/resources/canvas-tests.css">
<body class="show_output">

<h1>2d.text.drawing.style.letterSpacing.measure</h1>
<p class="desc">Testing letter spacing and word spacing</p>


<p class="output">Actual output:</p>
<canvas id="c" class="output" width="100" height="50"><p class="fallback">FAIL (fallback content)</p></canvas>

<ul id="d"></ul>
<script>
var t = async_test("Testing letter spacing and word spacing");
_addTest(function(canvas, ctx) {

_assertSame(ctx.letterSpacing, '0px', "ctx.letterSpacing", "'0px'");
_assertSame(ctx.wordSpacing, '0px', "ctx.wordSpacing", "'0px'");
var width_normal = ctx.measureText('Hello World').width;

function test_letter_spacing(value, difference_spacing, epsilon) {
  ctx.letterSpacing = value;
  _assertSame(ctx.letterSpacing, value, "ctx.letterSpacing", "value");
  _assertSame(ctx.wordSpacing, '0px', "ctx.wordSpacing", "'0px'");
  width_with_letter_spacing = ctx.measureText('Hello World').width;
  assert_approx_equals(width_with_letter_spacing, width_normal + difference_spacing, epsilon, "letter spacing doesn't work.");
}

// The first value is the letter Spacing to be set, the second value the
// change in length of string 'Hello World', note that there are 11 letters
// in 'hello world', so the length difference is always letterSpacing * 11.
// and the third value is the acceptable differencee for the length change,
// note that unit such as 1cm/1mm doesn't map to an exact pixel value.
test_cases = [['3px', 33, 0],
              ['5px', 55, 0],
              ['-2px', -22, 0],
              ['1em', 110, 0],
              ['1in', 1056, 0],
              ['-0.1cm', -41.65, 0.2],
              ['-0.6mm', -24,95, 0.2]]

for (const test_case of test_cases) {
  test_letter_spacing(test_case[0], test_case[1], test_case[2]);
}


});
</script>

