fix($resource): prevent URL template from collapsing into an empty st…

…ring

if url template would result in an empty string, we should make a request
to '/' instead.

Closes angular#5455
Closes angular#5493

src/ngResource/resource.js

@@ -401,7 +401,7 @@ angular.module('ngResource', ['ng']).
  });
 
  // strip trailing slashes and set the url
- url = url.replace(/\/+$/, '');
+ url = url.replace(/\/+$/, '') || '/';
  // then replace collapse `/.` if found in the last URL path segment before the query
  // E.g. `http://url.com/id./format?q=x` becomes `http://url.com/id.format?q=x`
  url = url.replace(/\/\.(?=\w+($|\?))/, '.');

test/ngResource/resourceSpec.js

@@ -150,6 +150,13 @@ describe("resource", function() {
  R.get({a:6, b:7, c:8});
  });
 
+ it('should not collapsed the url into an empty string', function() {
+ var R = $resource('/:foo/:bar/');
+
+ $httpBackend.when('GET', '/').respond('{}');
+
+ R.get({});
+ });
 
  it('should support escaping colons in url template', function() {
  var R = $resource('http://localhost\\:8080/Path/:a/\\:stillPath/:b');