lepu-test-platform-web/node_modules/postcss-discard-overridden/index.js

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import postcss from 'postcss';
const OVERRIDABLE_RULES = ['keyframes', 'counter-style'];
const SCOPE_RULES = ['media', 'supports'];
function isOverridable(name) {
return OVERRIDABLE_RULES.indexOf(postcss.vendor.unprefixed(name)) !== -1;
}
function isScope(name) {
return SCOPE_RULES.indexOf(postcss.vendor.unprefixed(name)) !== -1;
}
function getScope(node) {
let current = node.parent;
let chain = [node.name, node.params];
do {
if (current.type === 'atrule' && isScope(current.name)) {
chain.unshift(current.name + ' ' + current.params);
}
current = current.parent;
} while (current);
return chain.join('|');
}
export default postcss.plugin('postcss-discard-overridden', () => {
return css => {
let cache = {};
let rules = [];
css.walkAtRules(rule => {
if (rule.type === 'atrule' && isOverridable(rule.name)) {
let scope = getScope(rule);
cache[scope] = rule;
rules.push({
node: rule,
scope
});
}
});
rules.forEach(rule => {
if (cache[rule.scope] !== rule.node) {
rule.node.remove();
}
});
};
});