feat(StyleUrlResolver): rewrite url in styles

modules/angular2/src/core/compiler/style_url_resolver.js

@@ -0,0 +1,35 @@
+// Some of the code comes from WebComponents.JS
+// https://github.com/webcomponents/webcomponentsjs/blob/master/src/HTMLImports/path.js
+
+import {RegExp, RegExpWrapper, StringWrapper} from 'angular2/src/facade/lang';
+import {UrlResolver} from './url_resolver';
+
+export class StyleUrlResolver {
+  _resolver: UrlResolver;
+
+  constructor(resolver: UrlResolver) {
+    this._resolver = resolver;
+  }
+
+  resolveUrls(cssText: string, baseUrl: string) {
+    cssText = this._replaceUrls(cssText, _cssUrlRe, baseUrl);
+    cssText = this._replaceUrls(cssText, _cssImportRe, baseUrl);
+    return cssText;
+  }
+
+  _replaceUrls(cssText: string, re: RegExp, baseUrl: string) {
+    return StringWrapper.replaceAllMapped(cssText, re, (m) => {
+      var pre = m[1];
+      var url = StringWrapper.replaceAll(m[2], _quoteRe, '');
+      var post = m[3];
+
+      var resolvedUrl = this._resolver.resolve(baseUrl, url);
+
+      return pre + "'" + resolvedUrl + "'" + post;
+    });
+  }
+}
+
+var _cssUrlRe = RegExpWrapper.create('(url\\()([^)]*)(\\))');
+var _cssImportRe = RegExpWrapper.create('(@import[\\s]+(?!url\\())([^;]*)(;)');
+var _quoteRe = RegExpWrapper.create('[\'"]');

modules/angular2/test/core/compiler/style_url_resolver_spec.js

@@ -0,0 +1,41 @@
+import {describe, it, expect, beforeEach, ddescribe, iit, xit, el} from 'angular2/test_lib';
+import {StyleUrlResolver} from 'angular2/src/core/compiler/style_url_resolver';
+
+import {UrlResolver} from 'angular2/src/core/compiler/url_resolver';
+
+export function main() {
+  describe('StyleUrlResolver', () => {
+    it('should resolve urls', () => {
+      var styleUrlResolver = new StyleUrlResolver(new FakeUrlResolver());
+      var css = `
+      @import '1.css';
+      @import "2.css";
+      @import url('3.css');
+      @import url("4.css");
+
+      .foo {
+        background-image: url("double.jpg");
+        background-image: url('simple.jpg');
+      }`;
+      var expectedCss = `
+      @import 'base/1.css';
+      @import 'base/2.css';
+      @import url('base/3.css');
+      @import url('base/4.css');
+
+      .foo {
+        background-image: url('base/double.jpg');
+        background-image: url('base/simple.jpg');
+      }`;
+
+      var resolvedCss = styleUrlResolver.resolveUrls(css, 'base');
+      expect(resolvedCss).toEqual(expectedCss);
+    });
+  });
+}
+
+class FakeUrlResolver extends UrlResolver {
+  resolve(baseUrl: string, url: string): string {
+    return baseUrl + '/' + url;
+  }
+}