@smidswater/postcss-conditionals/dist/lib/process.js

PostCSS plugin that enables @if statements in your CSS

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = process;

var _evaluate = _interopRequireDefault(require("./evaluate"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function processIfRule(rule) {
  processExpression(rule, rule.params);
}

function processExpression(node, expr) {
  process(node);
  if (!expr) throw node.error('Missing condition', {
    plugin: 'postcss-conditionals'
  });
  var passed = (0, _evaluate.default)(expr);
  if (passed) node.before(node.nodes);
  processNextNode(node, !passed);
  node.remove();
}

function processNextNode(rule, evaluateNext) {
  var node = rule.next();
  if (typeof node === 'undefined') return;
  if (node.type !== 'atrule') return;
  if (node.name !== 'else') return;

  if (evaluateNext) {
    if (node.params.substr(0, 2) === 'if') processElseIfRule(node);else processElseRule(node);
  } else processNextNode(node, false);

  node.remove();
}

function processElseIfRule(rule) {
  processExpression(rule, rule.params.substr(3));
}

function processElseRule(rule) {
  process(rule);
  rule.before(rule.nodes);
}

function process(node) {
  node.walkAtRules('if', processIfRule);
}

module.exports = exports.default;