Split sort logic from configuration loading process

lib/create-sort.js

@@ -0,0 +1,245 @@
+// ----------------------------------------
+// Private
+// ----------------------------------------
+
+const minMaxWidth = /(!?\(\s*min(-device-)?-width)(.|\n)+\(\s*max(-device)?-width/i;
+const minWidth = /\(\s*min(-device)?-width/i;
+const maxMinWidth = /(!?\(\s*max(-device)?-width)(.|\n)+\(\s*min(-device)?-width/i;
+const maxWidth = /\(\s*max(-device)?-width/i;
+
+const isMinWidth = _testQuery(minMaxWidth, maxMinWidth, minWidth);
+const isMaxWidth = _testQuery(maxMinWidth, minMaxWidth, maxWidth);
+
+const minMaxHeight = /(!?\(\s*min(-device)?-height)(.|\n)+\(\s*max(-device)?-height/i;
+const minHeight = /\(\s*min(-device)?-height/i;
+const maxMinHeight = /(!?\(\s*max(-device)?-height)(.|\n)+\(\s*min(-device)?-height/i;
+const maxHeight = /\(\s*max(-device)?-height/i;
+
+const isMinHeight = _testQuery(minMaxHeight, maxMinHeight, minHeight);
+const isMaxHeight = _testQuery(maxMinHeight, minMaxHeight, maxHeight);
+
+const isPrint = /print/i;
+const isPrintOnly = /^print$/i;
+
+const maxValue = Number.MAX_VALUE;
+
+/**
+ * Obtain the length of the media request in pixels.
+ * Copy from original source `function inspectLength (length)`
+ * {@link https://github.com/hail2u/node-css-mqpacker/blob/master/index.js#L58}
+ * @private
+ * @param {string} length
+ * @return {number}
+ */
+function _getQueryLength(length) {
+	length = /(-?\d*\.?\d+)(ch|em|ex|px|rem)/.exec(length);
+
+	if (length === null) {
+		return maxValue;
+	}
+
+	let number = length[1];
+	const unit = length[2];
+
+	switch (unit) {
+		case 'ch':
+			number = parseFloat(number) * 8.8984375;
+			break;
+
+		case 'em':
+		case 'rem':
+			number = parseFloat(number) * 16;
+			break;
+
+		case 'ex':
+			number = parseFloat(number) * 8.296875;
+			break;
+
+		case 'px':
+			number = parseFloat(number);
+			break;
+	}
+
+	return +number;
+}
+
+/**
+ * Wrapper for creating test functions
+ * @private
+ * @param {RegExp} doubleTestTrue
+ * @param {RegExp} doubleTestFalse
+ * @param {RegExp} singleTest
+ * @return {Function}
+ */
+function _testQuery(doubleTestTrue, doubleTestFalse, singleTest) {
+	/**
+	 * @param {string} query
+	 * @return {boolean}
+	 */
+	return function (query) {
+		if (doubleTestTrue.test(query)) {
+			return true;
+		} else if (doubleTestFalse.test(query)) {
+			return false;
+		}
+		return singleTest.test(query);
+	};
+}
+
+/**
+ * @private
+ * @param {string} a
+ * @param {string} b
+ * @return {number|null}
+ */
+function _testIsPrint(a, b) {
+	const isPrintA = isPrint.test(a);
+	const isPrintOnlyA = isPrintOnly.test(a);
+
+	const isPrintB = isPrint.test(b);
+	const isPrintOnlyB = isPrintOnly.test(b);
+
+	if (isPrintA && isPrintB) {
+		if (!isPrintOnlyA && isPrintOnlyB) {
+			return 1;
+		}
+		if (isPrintOnlyA && !isPrintOnlyB) {
+			return -1;
+		}
+		return a.localeCompare(b);
+	}
+	if (isPrintA) {
+		return 1;
+	}
+	if (isPrintB) {
+		return -1;
+	}
+
+	return null;
+}
+
+// ----------------------------------------
+// Public
+// ----------------------------------------
+
+/**
+ * @param {Object} [configuration]
+ * @param {boolean} [configuration.unitlessMqAlwaysFirst]
+ * @returns {(function(string, string): number)|*}
+ */
+module.exports = function createSort(configuration) {
+	const config = configuration || {};
+
+	// eslint-disable-next-line no-unused-vars
+	const UNITLESS_MQ_ALWAYS_FIRST = config.unitlessMqAlwaysFirst;
+
+	/**
+	 * Sorting an array with media queries
+	 * according to the mobile-first methodology.
+	 * @param {string} a
+	 * @param {string} b
+	 * @return {number} 1 / 0 / -1
+	 */
+	function sortCSSmq(a, b) {
+		const testIsPrint = _testIsPrint(a, b);
+		if (testIsPrint !== null) {
+			return testIsPrint;
+		}
+
+		const minA = isMinWidth(a) || isMinHeight(a);
+		const maxA = isMaxWidth(a) || isMaxHeight(a);
+
+		const minB = isMinWidth(b) || isMinHeight(b);
+		const maxB = isMaxWidth(b) || isMaxHeight(b);
+
+		if (minA && maxB) {
+			return -1;
+		}
+		if (maxA && minB) {
+			return 1;
+		}
+
+		const lengthA = _getQueryLength(a);
+		const lengthB = _getQueryLength(b);
+
+		if (lengthA === maxValue && lengthB === maxValue) {
+			return a.localeCompare(b);
+		} else if (lengthA === maxValue) {
+			return 1;
+		} else if (lengthB === maxValue) {
+			return -1;
+		}
+
+		if (lengthA > lengthB) {
+			if (maxA) {
+				return -1;
+			}
+			return 1;
+		}
+
+		if (lengthA < lengthB) {
+			if (maxA) {
+				return 1;
+			}
+			return -1;
+		}
+
+		return a.localeCompare(b);
+	}
+
+	/**
+	 * Sorting an array with media queries
+	 * according to the desktop-first methodology.
+	 * @param {string} a
+	 * @param {string} b
+	 * @return {number} 1 / 0 / -1
+	 */
+	sortCSSmq.desktopFirst = function (a, b) {
+		const testIsPrint = _testIsPrint(a, b);
+		if (testIsPrint !== null) {
+			return testIsPrint;
+		}
+
+		const minA = isMinWidth(a) || isMinHeight(a);
+		const maxA = isMaxWidth(a) || isMaxHeight(a);
+
+		const minB = isMinWidth(b) || isMinHeight(b);
+		const maxB = isMaxWidth(b) || isMaxHeight(b);
+
+		if (minA && maxB) {
+			return 1;
+		}
+		if (maxA && minB) {
+			return -1;
+		}
+
+		const lengthA = _getQueryLength(a);
+		const lengthB = _getQueryLength(b);
+
+		if (lengthA === maxValue && lengthB === maxValue) {
+			return a.localeCompare(b);
+		} else if (lengthA === maxValue) {
+			return 1;
+		} else if (lengthB === maxValue) {
+			return -1;
+		}
+
+		if (lengthA > lengthB) {
+			if (maxA) {
+				return -1;
+			}
+			return 1;
+		}
+
+		if (lengthA < lengthB) {
+			if (maxA) {
+				return 1;
+			}
+			return -1;
+		}
+
+		return -a.localeCompare(b);
+	};
+
+	return sortCSSmq;
+};