lepu-test-platform-web/node_modules/postcss-minify-params/dist/index.js

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var postcss = require('postcss');
var valueParser = require('postcss-value-parser');
var stringify = valueParser.stringify;
var sort = require('alphanum-sort');
var uniqs = require('uniqs');
/**
* Return the greatest common divisor
* of two numbers.
*/
function gcd(a, b) {
return b ? gcd(b, a % b) : a;
}
function aspectRatio(a, b) {
var divisor = gcd(a, b);
return [a / divisor, b / divisor];
}
function split(nodes, div) {
var result = [];
var i, max, node;
var last = '';
for (i = 0, max = nodes.length; i < max; i += 1) {
node = nodes[i];
if (node.type === 'div' && node.value === div) {
result.push(last);
last = '';
} else {
last += stringify(node);
}
}
result.push(last);
return result;
}
function removeNode(node) {
node.value = '';
node.type = 'word';
}
module.exports = postcss.plugin('postcss-minify-params', function () {
return function (css) {
css.walkAtRules(function (rule) {
if (!rule.params) {
return;
}
var params = valueParser(rule.params);
params.walk(function (node, index) {
if (node.type === 'div' || node.type === 'function') {
node.before = node.after = '';
if (
node.type === 'function' &&
node.nodes[4] &&
node.nodes[0].value.indexOf('-aspect-ratio') === 3
) {
var ref = aspectRatio(
node.nodes[2].value,
node.nodes[4].value
);
var a = ref[0];
var b = ref[1];
node.nodes[2].value = a;
node.nodes[4].value = b;
}
} else if (node.type === 'space') {
node.value = ' ';
} else if (node.type === 'word') {
var prevWord = params.nodes[index - 2];
if (
node.value === 'all' &&
rule.name === 'media' &&
!prevWord
) {
var nextSpace = params.nodes[index + 1];
var nextWord = params.nodes[index + 2];
var secondSpace = params.nodes[index + 3];
if (nextWord && nextWord.value === 'and') {
removeNode(nextWord);
removeNode(nextSpace);
if (secondSpace) {
removeNode(secondSpace);
}
}
removeNode(node);
}
}
}, true);
rule.params = sort(uniqs(split(params.nodes, ',')), {
insensitive: true
}).join();
if (!rule.params.length) {
rule.raws.afterName = '';
}
});
};
});