refactor resolve function

Author: bbtfr

lib/createResolver.js

@@ -0,0 +1,51 @@
+function startsWith(string, searchString) {
+	var stringLength = string.length;
+	var searchLength = searchString.length;
+
+	// early out if the search length is greater than the search string
+	if(searchLength > stringLength) {
+		return false;
+	}
+	var index = -1;
+	while(++index < searchLength) {
+		if(string.charCodeAt(index) !== searchString.charCodeAt(index)) {
+			return false;
+		}
+	}
+	return true;
+}
+
+module.exports = function createResolver(alias) {
+	if(typeof alias !== "object" || Array.isArray(alias)) {
+		return function(url) { return url };
+	}
+
+	alias = Object.keys(alias).map(function(key) {
+		var onlyModule = false;
+		var obj = alias[key];
+		if(/\$$/.test(key)) {
+			onlyModule = true;
+			key = key.substr(0, key.length - 1);
+		}
+		if(typeof obj === "string") {
+			obj = {
+				alias: obj
+			};
+		}
+		obj = Object.assign({
+			name: key,
+			onlyModule: onlyModule
+		}, obj);
+		return obj;
+	});
+
+	return function(url) {
+		alias.forEach(function(obj) {
+			var name = obj.name;
+			if(url === name || (!obj.onlyModule && startsWith(url, name + "/"))) {
+				url = obj.alias + url.substr(name.length);
+			}
+		});
+		return url;
+	}
+}

lib/loader.js

@@ -6,6 +6,7 @@ var loaderUtils = require("loader-utils");
 var processCss = require("./processCss");
 var getImportPrefix = require("./getImportPrefix");
 var compileExports = require("./compile-exports");
+var createResolver = require("./createResolver");
 
 
 module.exports = function(content, map) {
@@ -15,6 +16,7 @@ module.exports = function(content, map) {
 	var root = query.root;
 	var moduleMode = query.modules || query.module;
 	var camelCaseKeys = query.camelCase || query.camelcase;
+	var resolve = createResolver(query.alias);
 
 	if(map !== null && typeof map !== "string") {
 		map = JSON.stringify(map);
@@ -69,19 +71,7 @@ module.exports = function(content, map) {
 				var match = result.urlItemRegExp.exec(item);
 				var idx = +match[1];
 				var urlItem = result.urlItems[idx];
-				var url = urlItem.url;
-				var loaderOptions = this.options.cssLoader;
-				if (loaderOptions && loaderOptions.alias) {
-					var alias = loaderOptions.alias;
-					Object.keys(alias).forEach(function(aliasName) {
-						var aliasValue = alias[aliasName];
-						var onlyModule = /\$$/.test(aliasName);
-						if (onlyModule) aliasName = aliasName.substr(0, aliasName.length - 1);
-						if ((!onlyModule && url.indexOf(aliasName + "/") === 0) || url === aliasName) {
-							url = aliasValue + url.substr(aliasName.length);
-						}
-					});
-				}
+				var url = resolve(urlItem.url);
 				idx = url.indexOf("?#");
 				if(idx < 0) idx = url.indexOf("#");
 				var urlRequest;

test/aliasTest.js

@@ -3,28 +3,28 @@
 var test = require("./helpers").test;
 
 describe("alias", function() {
-  var css = ".className { background: url(./path/to/file.png); }";
-  var exports = {
-    without: [
-      [1, ".className { background: url({./path/to/file.png}); }", ""]
-    ],
-    onlyModule: [
-      [1, ".className { background: url({module/file.png}); }", ""]
-    ],
-    exactMatch: [
-      [1, ".className { background: url({module/file.png}); }", ""]
-    ],
-    notExactMatch: [
-      [1, ".className { background: url({./path/to/file.png}); }", ""]
-    ]
-  };
+	var css = ".className { background: url(./path/to/file.png); }";
+	var exports = {
+		without: [
+			[1, ".className { background: url({./path/to/file.png}); }", ""]
+		],
+		onlyModule: [
+			[1, ".className { background: url({module/file.png}); }", ""]
+		],
+		exactMatch: [
+			[1, ".className { background: url({module/file.png}); }", ""]
+		],
+		notExactMatch: [
+			[1, ".className { background: url({./path/to/file.png}); }", ""]
+		]
+	};
 
-  function aliasOptions(alias) {
-    return { options: { context: "", cssLoader: { alias: alias }}}
-  }
+	function aliasOptions(alias) {
+		return { query: { alias: alias }}
+	}
 
-  test("without", css, exports.without);
-  test("onlyModule", css, exports.onlyModule, aliasOptions({ "./path/to": "module" }));
-  test("exactMatch", css, exports.exactMatch, aliasOptions({ "./path/to/file.png$": "module/file.png" }));
-  test("notExactMatch", css, exports.notExactMatch, aliasOptions({ "./path/to/file.jpg$": "module/file.jpg" }));
+	test("without", css, exports.without);
+	test("onlyModule", css, exports.onlyModule, aliasOptions({ "./path/to": "module" }));
+	test("exactMatch", css, exports.exactMatch, aliasOptions({ "./path/to/file.png$": "module/file.png" }));
+	test("notExactMatch", css, exports.notExactMatch, aliasOptions({ "./path/to/file.jpg$": "module/file.jpg" }));
 });