css/cssom/getComputedStyle-pseudo.html

<!doctype html>
<meta charset="utf-8">
<title>CSSOM: Correct resolution of resolved value for display-affected pseudo-elements</title>
<link rel="help" href="https://drafts.csswg.org/cssom/#dom-window-getcomputedstyle">
<link rel="help" href="https://drafts.csswg.org/cssom/#resolved-values">
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<style>
#test { width: 100px; }

#contents {
  display: contents;
  border: 10px solid red;
}

#test::before,
#test::after,
#contents::before,
#contents::after,
#flex::before,
#flex::after {
  content: " ";
  width: 50%;
  height: 10px;
  display: block;
}
#none {
  display: none;
}
#none::before,
#none::after {
  content: "Foo";
}
#flex {
  display: flex;
}
#flex-no-pseudo {
  display: flex;
}
#contents-pseudos::before,
#contents-pseudos::after {
  display: contents;
  content: "foo";
  position: absolute;
}
#contents-pseudos-dynamic::before,
#contents-pseudos-dynamic::after {
  display: block;
  content: "foo";
  position: absolute;
}
#contents-pseudos-dynamic.contents::before,
#contents-pseudos-dynamic.contents::after {
  display: contents;
}
</style>
<div id="test">
  <div id="contents"></div>
  <div id="none"></div>
  <div id="flex"></div>
  <div id="flex-no-pseudo"></div>
  <div id="contents-pseudos"></div>
  <div id="contents-pseudos-dynamic"></div>
</div>
<script>
test(function() {
  var div = document.getElementById('test');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(div, pseudo).width, "50px");
  });
}, "Resolution of width is correct for ::before and ::after pseudo-elements");
test(function() {
  var contents = document.getElementById('contents');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(contents, pseudo).width, "50px");
  });
}, "Resolution of width is correct for ::before and ::after pseudo-elements of display: contents elements");
test(function() {
  var has_no_pseudos = document.body;
  has_no_pseudos.style.position = "relative";
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(has_no_pseudos, pseudo).position, "static",
                  "Nonexistent " + pseudo + " pseudo-element shouldn't claim to have " +
                  "the same style as the originating element");
    assert_equals(getComputedStyle(has_no_pseudos, pseudo).width, "auto",
                  "Nonexistent " + pseudo + " pseudo-element shouldn't claim to have " +
                  "definite size");
  });
}, "Resolution of nonexistent pseudo-element styles");
test(function() {
  var none = document.getElementById('none');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(none, pseudo).content, "\"Foo\"",
                  "Pseudo-styles of display: none elements should be correct");
  });
}, "Resolution of pseudo-element styles in display: none elements");
test(function() {
  var flex = document.getElementById('flex');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(flex, pseudo).display, "block",
                  "Pseudo-styles of display: flex elements should get blockified");
  });
}, "Item-based blockification of pseudo-elements");
test(function() {
  var flexNoPseudo = document.getElementById('flex-no-pseudo');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(flexNoPseudo, pseudo).display, "block",
                  "Pseudo-styles of display: flex elements should get blockified");
  });
}, "Item-based blockification of nonexistent pseudo-elements");
test(function() {
  var contentsPseudos = document.getElementById('contents-pseudos');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(contentsPseudos, pseudo).display, "contents",
                  "display: contents in " + pseudo + " should get reflected on CSSOM");
    assert_equals(getComputedStyle(contentsPseudos, pseudo).width, "auto",
                  pseudo + " with display: contents should have no box");
    assert_equals(getComputedStyle(contentsPseudos, pseudo).position, "absolute",
                  "display: contents in " + pseudo + " should reflect other non-inherited properties in CSSOM");
  });
}, "display: contents on pseudo-elements");
test(function() {
  var contentsPseudosDynamic = document.getElementById('contents-pseudos-dynamic');
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(contentsPseudosDynamic, pseudo).display, "block",
                  "Check that display for " + pseudo + " is block before change");
  });
  contentsPseudosDynamic.className = "contents";
  [":before", ":after"].forEach(function(pseudo) {
    assert_equals(getComputedStyle(contentsPseudosDynamic, pseudo).display, "contents",
                  "display: contents in " + pseudo + " should get reflected on CSSOM");
    assert_equals(getComputedStyle(contentsPseudosDynamic, pseudo).width, "auto",
                  pseudo + " with display: contents should have no box");
    assert_equals(getComputedStyle(contentsPseudosDynamic, pseudo).position, "absolute",
                  "display: contents in " + pseudo + " should reflect other non-inherited properties in CSSOM");
  });
}, "Dynamically change to display: contents on pseudo-elements");
test(function() {
  var div = document.getElementById('test');
  assert_not_equals(
    getComputedStyle(div, "totallynotapseudo").length, 0,
    "Should return the element's style for unknown pseudo-elements that don't start with a colon");
  assert_equals(
    getComputedStyle(div, "::totallynotapseudo").length, 0,
    "Should return an empty style for unknown pseudo-elements starting with double-colon");
  assert_equals(
    getComputedStyle(div, ":totallynotapseudo").length, 0,
    "Should return an empty style for unknown pseudo-elements starting with colon");
}, "Unknown pseudo-elements");
</script>