'use strict';
function trimValue(value) {
return value ? value.trim() : value;
}
function empty(node) {
return !node.nodes.filter((child) => child.type !== 'comment').length;
}
function equals(nodeA, nodeB) {
const a = (nodeA);
const b = (nodeB);
if (a.type !== b.type) {
return false;
}
if (a.important !== b.important) {
return false;
}
if ((a.raws && !b.raws) || (!a.raws && b.raws)) {
return false;
}
switch (a.type) {
case 'rule':
if (a.selector !== b.selector) {
return false;
}
break;
case 'atrule':
if (a.name !== b.name || a.params !== b.params) {
return false;
}
if (a.raws && trimValue(a.raws.before) !== trimValue(b.raws.before)) {
return false;
}
if (
a.raws &&
trimValue(a.raws.afterName) !== trimValue(b.raws.afterName)
) {
return false;
}
break;
case 'decl':
if (a.prop !== b.prop || a.value !== b.value) {
return false;
}
if (a.raws && trimValue(a.raws.before) !== trimValue(b.raws.before)) {
return false;
}
break;
}
if (a.nodes) {
if (a.nodes.length !== b.nodes.length) {
return false;
}
for (let i = 0; i < a.nodes.length; i++) {
if (!equals(a.nodes[i], b.nodes[i])) {
return false;
}
}
}
return true;
}
function dedupeRule(last, nodes) {
let index = nodes.indexOf(last) - 1;
while (index >= 0) {
const node = nodes[index--];
if (node && node.type === 'rule' && node.selector === last.selector) {
last.each((child) => {
if (child.type === 'decl') {
dedupeNode(child, node.nodes);
}
});
if (empty(node)) {
node.remove();
}
}
}
}
function dedupeNode(last, nodes) {
let index = nodes.includes(last) ? nodes.indexOf(last) - 1 : nodes.length - 1;
while (index >= 0) {
const node = nodes[index--];
if (node && equals(node, last)) {
node.remove();
}
}
}
function dedupe(root) {
const { nodes } =
(
root
);
if (!nodes) {
return;
}
let index = nodes.length - 1;
while (index >= 0) {
let last = nodes[index--];
if (!last || !last.parent) {
continue;
}
dedupe(last);
if (last.type === 'rule') {
dedupeRule(last, nodes);
} else if (last.type === 'atrule' || last.type === 'decl') {
dedupeNode(last, nodes);
}
}
}
function pluginCreator() {
return {
postcssPlugin: 'postcss-discard-duplicates',
OnceExit(css) {
dedupe(css);
},
};
}
pluginCreator.postcss = true;
module.exports = pluginCreator;