<!DOCTYPE html>
<title>CSS Anchor Positioning Test: @position-try - tree scoped names</title>
<link rel="help" href="https://drafts.csswg.org/css-anchor-1/#fallback-rule">
<link rel="help" href="https://drafts.csswg.org/css-scoping/#shadow-names">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
body { margin: 0; }
@position-try --doc {
left: 100px;
}
.abs {
width: 100px;
position: absolute;
left: 999999px; /* force fallback */
}
#doc_pf_doc { position-try-fallbacks: --doc; }
#doc_pf_outer { position-try-fallbacks: --outer; }
#doc_pf_inner { position-try-fallbacks: --inner; }
</style>
<div id="doc_pf_doc" class="abs"></div>
<div id="doc_pf_outer" class="abs"></div>
<div id="doc_pf_inner" class="abs"></div>
<div id="outer_host">
<template shadowrootmode="open">
<style>
@position-try --outer {
left: 200px;
}
.abs {
position: absolute;
left: 999999px; /* force fallback */
}
#outer_pf_doc { position-try-fallbacks: --doc; }
#outer_pf_outer { position-try-fallbacks: --outer; }
#outer_pf_inner { position-try-fallbacks: --inner; }
</style>
<div id="outer_pf_doc" class="abs"></div>
<div id="outer_pf_outer" class="abs"></div>
<div id="outer_pf_inner" class="abs"></div>
<div id="inner_host">
<template shadowrootmode="open">
<style>
@position-try --inner {
left: 300px;
}
.abs {
position: absolute;
left: 999999px; /* force fallback */
}
#inner_pf_doc { position-try-fallbacks: --doc; }
#inner_pf_outer { position-try-fallbacks: --outer; }
#inner_pf_inner { position-try-fallbacks: --inner; }
</style>
<div id="inner_pf_doc" class="abs"></div>
<div id="inner_pf_outer" class="abs"></div>
<div id="inner_pf_inner" class="abs"></div>
</template>
</div>
</template>
</div>
<style>
#host_slotted_part {
width: 100px;
}
@position-try --host-slot-part {
left: 1px;
}
#host_slotted_part::part(part) {
position-try-fallbacks: --host-slot-part;
}
</style>
<div id="host_slotted_part">
<template shadowrootmode="open">
<style>
@position-try --host-slot-part {
left: 2px;
}
::slotted(#slotted), :host {
position: absolute;
left: 999999px; /* force fallback */
position-try-fallbacks: --host-slot-part;
}
#part {
position: absolute;
left: 999999px; /* force fallback */
}
</style>
<div id="part" part="part"></div>
<slot></slot>
</template>
<div id="slotted"></div>
</div>
<script>
test(() => {
assert_equals(doc_pf_doc.offsetLeft, 100);
}, "Document position-try-fallbacks matches @position-try in document scope");
test(() => {
assert_equals(doc_pf_outer.offsetLeft, 999999);
}, "Document position-try-fallbacks does not match @position-try in #outer_host scope");
test(() => {
assert_equals(doc_pf_inner.offsetLeft, 999999);
}, "Document position-try-fallbacks does not match @position-try in #inner_host scope");
const outer_root = outer_host.shadowRoot;
const inner_root = outer_root.querySelector("#inner_host").shadowRoot;
test(() => {
assert_equals(outer_root.querySelector("#outer_pf_doc").offsetLeft, 100);
}, "Outer position-try-fallbacks matches @position-try in document scope");
test(() => {
assert_equals(outer_root.querySelector("#outer_pf_outer").offsetLeft, 200);
}, "Outer position-try-fallbacks matches @position-try in #outer_host scope");
test(() => {
assert_equals(outer_root.querySelector("#outer_pf_inner").offsetLeft, 999999);
}, "Outer position-try-fallbacks does not match @position-try in #inner_host scope");
test(() => {
assert_equals(inner_root.querySelector("#inner_pf_doc").offsetLeft, 100)
}, "Inner position-try-fallbacks matches @position-try in document scope");
test(() => {
assert_equals(inner_root.querySelector("#inner_pf_outer").offsetLeft, 200);
}, "Inner position-try-fallbacks matches @position-try in #outer_host scope");
test(() => {
assert_equals(inner_root.querySelector("#inner_pf_inner").offsetLeft, 300);
}, "Inner position-try-fallbacks matches @position-try in #inner_host scope");
test(() => {
assert_equals(host_slotted_part.offsetLeft, 2);
}, "@position-try from same scope as :host rule");
test(() => {
assert_equals(slotted.offsetLeft, 2);
}, "@position-try from same scope as ::slotted() rule");
test(() => {
assert_equals(host_slotted_part.shadowRoot.querySelector("#part").offsetLeft, 1);
}, "@position-try from same scope as ::part() rule");
</script>