Support "relative" URLs in component decorators.

We get resolved absolute paths from Angular prefixed by a "//"

Author: hdeshev

src/nativescript-angular/xhr.ts

@@ -2,14 +2,24 @@ import {path, knownFolders, File} from "file-system";
 import {XHR} from "@angular/compiler/src/xhr";
 
 export class FileSystemXHR extends XHR {
-  get(url: string): Promise<string> {
-      let appDir = knownFolders.currentApp().path;
-      let templatePath = path.join(appDir, url);
+    resolve(url: string, baseUrl: string): string {
+        //Angular assembles absolute URL's and prefixes them with //
+        if (url.indexOf("//") !== 0) {
+            //Resolve relative URL's based on the app root.
+            return path.join(baseUrl, url);
+        } else {
+            return url;
+        }
+    }
 
-      if (!File.exists(templatePath)) {
-          throw new Error(`File ${url} does not exist.`);
-      }
-      let templateFile = File.fromPath(templatePath);
-      return templateFile.readText();
-  }
+    get(url: string): Promise<string> {
+        const appDir = knownFolders.currentApp().path;
+        const templatePath = this.resolve(url, appDir);
+
+        if (!File.exists(templatePath)) {
+            throw new Error(`File ${templatePath} does not exist. Resolved from: ${url}.`);
+        }
+        let templateFile = File.fromPath(templatePath);
+        return templateFile.readText();
+    }
 }

tests/app/tests/xhr-paths.ts

@@ -0,0 +1,15 @@
+//make sure you import mocha-config before @angular/core
+import {assert} from "./test-config";
+import {FileSystemXHR} from "nativescript-angular/xhr";
+
+describe("XHR name resolution", () => {
+    it("resolves relative paths from app root", () => {
+        const xhr = new FileSystemXHR();
+        assert.strictEqual("/app/dir/mydir/mycomponent.html", xhr.resolve("mydir/mycomponent.html", "/app/dir"))
+    });
+
+    it("resolves absolute paths as is", () => {
+        const xhr = new FileSystemXHR();
+        assert.strictEqual("//app/mydir/mycomponent.html", xhr.resolve("//app/mydir/mycomponent.html", "/app/dir"))
+    });
+})