<!DOCTYPE html>
<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
<title>OffscreenCanvas test: 2d.text.drawing.style.wordSpacing.measure</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/html/canvas/resources/canvas-tests.js"></script>

<h1>2d.text.drawing.style.wordSpacing.measure</h1>
<p class="desc">Testing if word spacing is working properly</p>


<script>
var t = async_test("Testing if word spacing is working properly");
var t_pass = t.done.bind(t);
var t_fail = t.step_func(function(reason) {
    throw reason;
});
t.step(function() {

var canvas = new OffscreenCanvas(100, 50);
var ctx = canvas.getContext('2d');

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

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

// The first value is the word Spacing to be set, the second value the
// change in length of string 'Hello World', note that there are 2 words
// in 'Hello World, again', so the length difference is always wordSpacing * 2.
// 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', 6, 0],
              ['5px', 10, 0],
              ['-2px', -4, 0],
              ['1em', 20, 0],
              ['1in', 192, 0],
              ['-0.1cm', -7.57, 0.2],
              ['-0.6mm', -4.54, 0.2]]

for (const test_case of test_cases) {
  test_word_spacing(test_case[0], test_case[1], test_case[2]);
}
t.done();

});
</script>
