css/css-cascade/scope-nesting.html

<!DOCTYPE html>
<title>@scope - nesting (&)</title>
<link rel="help" href="https://drafts.csswg.org/css-cascade-6/#scope-atrule">
<link rel="help" href="https://drafts.csswg.org/css-nesting-1/#nest-selector">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<main id=main></main>

<template id=test_nest_scope_end>
  <div>
    <style>
      @scope (.a) to (& > &) {
        * { z-index:1; }
      }
    </style>
    <div class=a> <!-- This scope is limited by the element below. -->
      <div class=a> <!-- This scope is limited by its own root. -->
        <div id=below></div>
      </div>
    </div>
  </div>
  <div id=outside></div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_nest_scope_end.content.cloneNode(true));

  assert_equals(getComputedStyle(below).zIndex, 'auto');
  assert_equals(getComputedStyle(outside).zIndex, 'auto');
}, 'Nesting-selector in <scope-end>');
</script>

<template id=test_nest_scope_end_implicit_scope>
  <div>
    <style>
      /* (.b) behaves like (:scope .b), due :scope being prepended
          implicitly. */
      @scope (.a) to (.b) {
        :scope { z-index:1; }
      }

      /* Should not match, since <scope-end> refers to the scope itself. */
      @scope (.a) to (.b:scope) {
        :scope { z-index:42; }
      }
    </style>
    <div class="a b">
      <div class=b>
        <div id=below></div>
      </div>
    </div>
  </div>
  <div id=outside></div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_nest_scope_end_implicit_scope.content.cloneNode(true));
  let a = document.querySelector('.a');
  let b = document.querySelector('.a > .b');
  assert_equals(getComputedStyle(a).zIndex, '1');
  assert_equals(getComputedStyle(b).zIndex, 'auto');
  assert_equals(getComputedStyle(below).zIndex, 'auto');
  assert_equals(getComputedStyle(outside).zIndex, 'auto');
}, 'Implicit :scope in <scope-end>');
</script>

<template id=test_relative_selector_scope_end>
  <div>
    <style>
      @scope (.a) to (> .b) {
        *, :scope { z-index:1; }
      }
    </style>
    <div class="a b">
      <div class=b>
        <div id=below></div>
      </div>
    </div>
  </div>
  <div id=outside></div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_relative_selector_scope_end.content.cloneNode(true));
  let a = document.querySelector('.a');
  let b = document.querySelector('.a > .b');
  assert_equals(getComputedStyle(a).zIndex, '1');
  assert_equals(getComputedStyle(b).zIndex, 'auto');
  assert_equals(getComputedStyle(below).zIndex, 'auto');
  assert_equals(getComputedStyle(outside).zIndex, 'auto');
}, 'Relative selectors in <scope-end>');
</script>

<template id=test_inner_nest>
  <div>
    <style>
      @scope (.a) {
        & + & {
          z-index:1;
        }
      }
    </style>
    <div class=a>
      <div id=inner1 class=a></div>
      <div id=inner2 class=a></div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_inner_nest.content.cloneNode(true));

  assert_equals(getComputedStyle(inner1).zIndex, 'auto');
  assert_equals(getComputedStyle(inner2).zIndex, '1');
}, 'Nesting-selector in the scope\'s <stylesheet>');
</script>

<template id=test_parent_in_pseudo_scope>
  <div>
    <style>
      @scope (#div) {
        :scope {
          z-index: 1;
          & {
            z-index: 2;
          }
        }
      }
    </style>
    <div id=div></div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_parent_in_pseudo_scope.content.cloneNode(true));

  assert_equals(getComputedStyle(div).zIndex, '2');
}, 'Nesting-selector within :scope rule');
</script>

<template id=test_parent_in_pseudo_scope_double>
  <div>
    <style>
      @scope (#div) {
        :scope {
          z-index: 1;
          & {
            & {
              z-index: 2;
            }
          }
        }
      }
    </style>
    <div id=div></div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_parent_in_pseudo_scope_double.content.cloneNode(true));

  assert_equals(getComputedStyle(div).zIndex, '2');
}, 'Nesting-selector within :scope rule (double nested)');
</script>

<template id=test_scope_within_style_rule>
  <div>
    <style>
      .a {
        @scope (.b) {
          .c { z-index: 1; }
        }
      }
    </style>
    <div class=a>
      <div class=b>
        <div class=c>
        </div>
      </div>
      <div id=out_of_scope class=c>
      </div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_scope_within_style_rule.content.cloneNode(true));

  let c = document.querySelector('.c');
  assert_equals(getComputedStyle(c).zIndex, '1');
  assert_equals(getComputedStyle(out_of_scope).zIndex, 'auto');
}, '@scope nested within style rule');
</script>

<template id=test_parent_pseudo_in_nested_scope_start>
  <div>
    <style>
      .a {
        @scope (&.b) {
          :scope { z-index: 1; }
        }
      }
    </style>
    <div class=a></div>
    <div class=b></div>
    <div class="a b"></div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_parent_pseudo_in_nested_scope_start.content.cloneNode(true));

  let a = document.querySelector('.a:not(.b)');
  let b = document.querySelector('.b:not(.a)');
  let ab = document.querySelector('.a.b');
  assert_equals(getComputedStyle(a).zIndex, 'auto');
  assert_equals(getComputedStyle(b).zIndex, 'auto');
  assert_equals(getComputedStyle(ab).zIndex, '1');
}, 'Parent pseudo class within scope-start');
</script>

<template id=test_parent_pseudo_in_nested_scope_end>
  <div>
    <style>
      .a {
        /* Note that & in <scope-end> refers to <scope-start>,
           not the outer style rule. */
        @scope (&.b) to (&.c) {
           :scope, * { z-index: 1; }
        }
      }
    </style>
    <div class="a b">
      <div class="a c">
        <div class="a b c">
        </div>
      </div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_parent_pseudo_in_nested_scope_end.content.cloneNode(true));

  let ab = document.querySelector('.a.b:not(.c)');
  let ac = document.querySelector('.a.c:not(.b)');
  let abc = document.querySelector('.a.b.c');
  assert_equals(getComputedStyle(ab).zIndex, '1');
  assert_equals(getComputedStyle(ac).zIndex, '1');
  assert_equals(getComputedStyle(abc).zIndex, 'auto', 'limit element is not in scope');
}, 'Parent pseudo class within scope-end');
</script>

<template id=test_parent_pseudo_in_nested_scope_body>
  <div>
    <style>
      .a {
        @scope (.b) {
           /* The & points to <scope-start>, which contains an implicit &
              which points to .a. */
           &.c { z-index: 1; }
        }
      }
    </style>
    <div class=a>
      <div class=b>
        <div class="c"></div>
        <div class="a c"></div>
        <div class="a b c" matching></div>
      </div>
    </div>
    <div>
      <div class=a></div>
      <div class=b></div>
      <div class=c></div>
      <div class="a b"></div>
      <div class="a c"></div>
      <div class="b c"></div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_parent_pseudo_in_nested_scope_body.content.cloneNode(true));

  let matching = main.querySelectorAll("div[matching]");
  let non_matching = main.querySelectorAll("div:not([matching])");

  for (let m of matching) {
    assert_equals(getComputedStyle(m).zIndex, '1', `matching: ${m.nodeName}${m.className}`);
  }
  for (let m of non_matching) {
    assert_equals(getComputedStyle(m).zIndex, 'auto', `non-matching: ${m.nodeName}${m.className}`);
  }
}, 'Parent pseudo class within body of nested @scope');
</script>

<template id=test_direct_declarations_in_nested_scope>
  <div>
    <style>
      .a {
        @scope (.b) {
          z-index: 1;
        }
      }
    </style>
    <div class=a>
      <div class=b>
        <div class="c"></div>
      </div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_direct_declarations_in_nested_scope.content.cloneNode(true));

  let a = document.querySelector('.a');
  let b = document.querySelector('.b');
  let c = document.querySelector('.c');
  assert_equals(getComputedStyle(a).zIndex, 'auto');
  assert_equals(getComputedStyle(b).zIndex, '1');
  assert_equals(getComputedStyle(c).zIndex, 'auto');
}, 'Implicit rule within nested @scope ');
</script>

<template id=test_direct_declarations_in_nested_scope_proximity>
  <div>
    <style>
      .a {
        /* We're supposed to prepend :scope to this declaration. If we do that,
           then :where() does not matter, since :scope does not gain any
           specificity from the enclosing @scope rule. However, if an
           implementation incorrectly prepends & instead, then :where() is
           needed to avoid the test incorrectly passing due to specificity. */
        @scope (:where(&) .b) {
          z-index: 1; /* Should win due to proximity */
        }
      }
      .b { z-index: 2; }
    </style>
    <div class=a>
      <div class="b x">
        <div class=c>
        </div>
      </div>
    </div>
  </div>
</template>
<script>
test((t) => {
  t.add_cleanup(() => main.replaceChildren());
  main.append(test_direct_declarations_in_nested_scope_proximity.content.cloneNode(true));

  let a = document.querySelector('.a');
  let b = document.querySelector('.b');
  let c = document.querySelector('.c');
  assert_equals(getComputedStyle(a).zIndex, 'auto');
  assert_equals(getComputedStyle(b).zIndex, '1');
  assert_equals(getComputedStyle(c).zIndex, 'auto');
}, 'Implicit rule within nested @scope (proximity)');
</script>