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Diffstat (limited to 'layout/style/test/test_invalidation_basic.html')
| -rw-r--r-- | layout/style/test/test_invalidation_basic.html | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/layout/style/test/test_invalidation_basic.html b/layout/style/test/test_invalidation_basic.html new file mode 100644 index 0000000000..b5a6928405 --- /dev/null +++ b/layout/style/test/test_invalidation_basic.html @@ -0,0 +1,45 @@ +<!doctype html> +<meta charset="utf-8"> +<title> + Test for bug 1368240: We only invalidate style as little as needed +</title> +<link rel="author" href="mailto:emilio@crisal.io" title="Emilio Cobos Álvarez"> +<script src="/tests/SimpleTest/SimpleTest.js"></script> +<style> +.foo .bar { + color: red; +} +#container ~ .bar { + color: green; +} +</style> +<div id="container"> + <div></div> + <div></div> + <div></div> +</div> +<div></div> +<div></div> +<script> +SimpleTest.waitForExplicitFinish(); +const utils = SpecialPowers.getDOMWindowUtils(window); + +// TODO(emilio): Add an API to get the ComputedStyles we've recreated, to make +// more elaborated tests. +document.documentElement.offsetTop; +const initialRestyleGeneration = utils.restyleGeneration; + +// Normally we'd restyle the whole subtree in this case, but we should go down +// the tree invalidating as little as needed (nothing in this case). +container.classList.add("foo"); +document.documentElement.offsetTop; +is(utils.restyleGeneration, initialRestyleGeneration, + "Shouldn't have restyled any descendant"); + +container.setAttribute("id", ""); +document.documentElement.offsetTop; +is(utils.restyleGeneration, initialRestyleGeneration, + "Shouldn't have restyled any sibling"); + +SimpleTest.finish(); +</script> |