<!DOCTYPE html>
<link rel="help" href="https://drafts.css-houdini.org/css-properties-values-api-1/#at-property-rule">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="./resources/utils.js"></script>
<div id="outer">
<div id="target"></div>
</div>
<script>
// Parsing:
let uppercase_first = (x) => x.charAt(0).toUpperCase() + x.slice(1);
let to_camel_case = (x) => x.split('-')[0] + x.split('-').slice(1).map(uppercase_first).join('');
function get_cssom_descriptor_value(rule, descriptor) {
switch (descriptor) {
case 'syntax':
return rule.syntax;
case 'inherits':
return rule.inherits;
case 'initial-value':
return rule.initialValue;
default:
assert_true(false, 'Should not reach here');
return null;
}
}
// Test that for the given descriptor (e.g. 'syntax'), the specified value
// will yield the expected_value when observed using CSSOM. If the expected_value
// is omitted, it is the same as the specified value.
function test_descriptor(descriptor, specified_value, expected_value, other_descriptors) {
// Try and build a valid @property form the specified descriptor.
let at_property = { [to_camel_case(descriptor)]: specified_value };
// If extra values are specified in other_descriptors, just use them.
if (typeof(other_descriptors) !== 'unspecified') {
for (let name in other_descriptors) {
if (other_descriptors.hasOwnProperty(name)) {
if (name == descriptor) {
throw `Unexpected ${name} in other_descriptors`;
}
at_property[to_camel_case(name)] = other_descriptors[name];
}
}
}
if (!('syntax' in at_property)) {
// The syntax descriptor is required. Use the universal one as a fallback.
// https://drafts.css-houdini.org/css-properties-values-api-1/#the-syntax-descriptor
at_property.syntax = '"*"';
}
if (!('inherits' in at_property)) {
// The inherits descriptor is required. Make it true as a fallback.
// https://drafts.css-houdini.org/css-properties-values-api-1/#inherits-descriptor
at_property.inherits = true;
}
if (!at_property.syntax.match(/^"\s*\*\s*"$/) &&
!('initialValue' in at_property)) {
// The initial-value is required for non-universal syntax.
// Pick a computationally independent value that follows specified syntax.
// https://drafts.css-houdini.org/css-properties-values-api-1/#the-syntax-descriptor
at_property.initialValue = (() => {
let first_syntax_component = specified_value
.replace(/^"(.*)"$/, '$1') // unquote
.replace(/[\s\uFEFF\xA0]+/g, ' ') // collapse whitespaces
.match(/^[^|\#\+]*/)[0] // pick first component
.trim();
switch (first_syntax_component) {
case '<color>': return 'blue';
case '<length>': return '42px';
default:
if (first_syntax_component.startsWith('<')) {
throw `Unsupported data type name '${first_syntax_component}'`;
}
return first_syntax_component; // <custom-ident>
}
})();
}
if (expected_value === null) {
test_with_at_property(at_property, (name, rule) => {
assert_true(!rule);
}, `Attribute '${descriptor}' makes the @property rule invalid for [${specified_value}]`);
} else {
if (typeof(expected_value) === 'undefined')
expected_value = specified_value;
test_with_at_property(at_property, (name, rule) => {
assert_equals(get_cssom_descriptor_value(rule, descriptor), expected_value);
}, `Attribute '${descriptor}' returns expected value for [${specified_value}]`);
}
}
// syntax
test_descriptor('syntax', '"<color>"', '<color>');
test_descriptor('syntax', '"<color> | none"', '<color> | none');
test_descriptor('syntax', '"<color># | <image> | none"', '<color># | <image> | none');
test_descriptor('syntax', '"foo | <length>#"', 'foo | <length>#');
test_descriptor('syntax', '"foo | bar | baz"', 'foo | bar | baz');
test_descriptor('syntax', '"notasyntax"', 'notasyntax');
// syntax: universal
for (const syntax of ["*", " * ", "* ", "\t*\t"]) {
test_descriptor('syntax', `"${syntax}"`, syntax);
}
// syntax: <color> value
test_descriptor('syntax', '"red"', "red"); // treated as <custom-ident>.
test_descriptor('syntax', '"rgb(255, 0, 0)"', null);
// syntax: missing quotes
test_descriptor('syntax', '<color>', null);
test_descriptor('syntax', 'foo | bar', null);
// syntax: invalid <custom-ident>
// https://drafts.csswg.org/css-values-4/#custom-idents
for (const syntax of
["default",
"initial",
"inherit",
"unset",
"revert",
"revert-layer",
]) {
test_descriptor('syntax', `"${syntax}"`, null);
test_descriptor('syntax', `"${uppercase_first(syntax)}"`, null);
}
// syntax: pipe between components
test_descriptor('syntax', '"foo bar"', null, {'initial-value': 'foo bar'});
test_descriptor('syntax', '"Foo <length>"', null, {'initial-value': 'Foo 42px'});
test_descriptor('syntax', '"foo, bar"', null, {'initial-value': 'foo, bar'});
test_descriptor('syntax', '"<length> <percentage>"', null, {'initial-value': '42px 100%'});
// syntax: leading bar
test_descriptor('syntax', '"|<length>"', null, {'initial-value': '42px'});
// initial-value
test_descriptor('initial-value', '10px');
test_descriptor('initial-value', 'rgb(1, 2, 3)');
test_descriptor('initial-value', 'red');
test_descriptor('initial-value', 'foo');
test_descriptor('initial-value', 'if(){}');
// initial-value: not computationally independent
test_descriptor('initial-value', '3em', null, {'syntax': '"<length>"'});
test_descriptor('initial-value', 'var(--x)', null);
// inherits
test_descriptor('inherits', 'true', true);
test_descriptor('inherits', 'false', false);
test_descriptor('inherits', 'none', null);
test_descriptor('inherits', '0', null);
test_descriptor('inherits', '1', null);
test_descriptor('inherits', '"true"', null);
test_descriptor('inherits', '"false"', null);
test_descriptor('inherits', 'calc(0)', null);
test_with_style_node('@property foo { }', (node) => {
assert_equals(node.sheet.rules.length, 0);
}, 'Invalid property name does not parse [foo]');
test_with_style_node('@property -foo { }', (node) => {
assert_equals(node.sheet.rules.length, 0);
}, 'Invalid property name does not parse [-foo]');
// Applying @property rules
function test_applied(syntax, initial, inherits, expected) {
test_with_at_property({
syntax: `"${syntax}"`,
initialValue: initial,
inherits: inherits
}, (name, rule) => {
let actual = getComputedStyle(target).getPropertyValue(name);
assert_equals(actual, expected);
}, `Rule applied [${syntax}, ${initial}, ${inherits}]`);
}
function test_not_applied(syntax, initial, inherits) {
test_with_at_property({
syntax: `"${syntax}"`,
initialValue: initial,
inherits: inherits
}, (name, rule) => {
let actual = getComputedStyle(target).getPropertyValue(name);
assert_equals(actual, '');
}, `Rule not applied [${syntax}, ${initial}, ${inherits}]`);
}
// syntax, initialValue, inherits, expected
test_applied('*', 'if(){}', false, 'if(){}');
test_applied('<angle>', '42deg', false, '42deg');
test_applied('<angle>', '1turn', false, '360deg');
test_applied('<color>', 'green', false, 'rgb(0, 128, 0)');
test_applied('<color>', 'rgb(1, 2, 3)', false, 'rgb(1, 2, 3)');
test_applied('<image>', 'url("http://a/")', false, 'url("http://a/")');
test_applied('<integer>', '5', false, '5');
test_applied('<length-percentage>', '10px', false, '10px');
test_applied('<length-percentage>', '10%', false, '10%');
test_applied('<length-percentage>', 'calc(10% + 10px)', false, 'calc(10% + 10px)');
test_applied('<length>', '10px', false, '10px');
test_applied('<number>', '2.5', false, '2.5');
test_applied('<percentage>', '10%', false, '10%');
test_applied('<resolution>', '50dppx', false, '50dppx');
test_applied('<resolution>', '96dpi', false, '1dppx');
test_applied('<time>', '10s', false, '10s');
test_applied('<time>', '1000ms', false, '1s');
test_applied('<transform-function>', 'rotateX(0deg)', false, 'rotateX(0deg)');
test_applied('<transform-list>', 'rotateX(0deg)', false, 'rotateX(0deg)');
test_applied('<transform-list>', 'rotateX(0deg) translateX(10px)', false, 'rotateX(0deg) translateX(10px)');
test_applied('<url>', 'url("http://a/")', false, 'url("http://a/")');
test_applied("<string>", "'foo bar'", false, '"foo bar"');
test_applied("<string>", " 'foo bar' ", false, '"foo bar"');
test_applied("<string>", `'"foo" bar'`, false, '"\\"foo\\" bar"');
test_applied("<string>", '"bar baz"', false, '"bar baz"');
test_applied("<string>", `"bar 'baz'"`, false, `"bar 'baz'"`);
test_applied("<string>+", "'foo' 'bar'", false, '"foo" "bar"');
test_applied("<string>#", "'foo', 'bar'", false, '"foo", "bar"');
test_applied("<string>+ | <string>#", "'foo' 'bar'", false, '"foo" "bar"');
test_applied("<string>+ | <string>#", " 'foo' 'bar'", false, '"foo" "bar"');
test_applied("<string>+ | <string>#", `'foo' "bar"`, false, '"foo" "bar"');
test_applied("<string># | <string>+", "'foo', 'bar'", false, '"foo", "bar"');
test_applied("<string># | <string>+", "'foo', 'bar' ", false, '"foo", "bar"');
test_applied("<string># | <string>+", `"foo", 'bar'`, false, '"foo", "bar"');
test_not_applied("<string>", "1px", false);
test_not_applied("<string>", "foo", false);
test_not_applied("<string>", "calc(1 + 2)", false);
test_not_applied("<string>", "rgb(255, 99, 71)", false);
test_not_applied("<string>", "'foo' 2px", false);
// inherits: true/false
test_applied('<color>', 'tomato', false, 'rgb(255, 99, 71)');
test_applied('<color>', 'tomato', true, 'rgb(255, 99, 71)');
test_with_at_property({ syntax: '"*"', inherits: true }, (name, rule) => {
try {
outer.style.setProperty(name, 'foo');
let actual = getComputedStyle(target).getPropertyValue(name);
assert_equals(actual, 'foo');
} finally {
outer.style = '';
}
}, 'Rule applied for "*", even with no initial value');
test_not_applied(undefined, 'green', false);
test_not_applied('<color>', undefined, false);
test_not_applied('<color>', 'green', undefined);
test_not_applied('<gandalf>', 'grey', false);
test_not_applied('gandalf', 'grey', false);
test_not_applied('<color>', 'notacolor', false);
test_not_applied('<length>', '10em', false);
test_not_applied('<transform-function>', 'translateX(1em)', false);
test_not_applied('<transform-function>', 'translateY(1lh)', false);
test_not_applied('<transform-list>', 'rotate(10deg) translateX(1em)', false);
test_not_applied('<transform-list>', 'rotate(10deg) translateY(1lh)', false);
// Inheritance
test_with_at_property({
syntax: '"<length>"',
inherits: false,
initialValue: '0px'
}, (name, rule) => {
try {
outer.style = `${name}: 40px`;
assert_equals(getComputedStyle(outer).getPropertyValue(name), '40px');
assert_equals(getComputedStyle(target).getPropertyValue(name), '0px');
} finally {
outer.style = '';
}
}, 'Non-inherited properties do not inherit');
test_with_at_property({
syntax: '"<length>"',
inherits: true,
initialValue: '0px'
}, (name, rule) => {
try {
outer.style = `${name}: 40px`;
assert_equals(getComputedStyle(outer).getPropertyValue(name), '40px');
assert_equals(getComputedStyle(target).getPropertyValue(name), '40px');
} finally {
outer.style = '';
}
}, 'Inherited properties inherit');
// Initial values
test_with_at_property({
syntax: '"<color>"',
inherits: true,
initialValue: 'green'
}, (name, rule) => {
try {
target.style = `--x:var(${name})`;
assert_equals(getComputedStyle(target).getPropertyValue(name), 'rgb(0, 128, 0)');
} finally {
target.style = '';
}
}, 'Initial values substituted as computed value');
test_with_at_property({
syntax: '"<length>"',
inherits: false,
initialValue: undefined
}, (name, rule) => {
try {
target.style = `${name}: calc(1px + 1px);`;
assert_equals(getComputedStyle(target).getPropertyValue(name), 'calc(1px + 1px)');
} finally {
target.style = '';
}
}, 'Non-universal registration are invalid without an initial value');
test_with_at_property({
syntax: '"*"',
inherits: false,
initialValue: undefined
}, (name, rule) => {
try {
// If the registration suceeded, ${name} does *not* inherit, and hence
// the computed value on 'target' should be empty.
outer.style = `${name}: calc(1px + 1px);`;
assert_equals(getComputedStyle(target).getPropertyValue(name), '');
} finally {
outer.style = '';
}
}, 'Initial value may be omitted for universal registration');
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