Angularjs How uri components are encoded

I was expecting AngularJS to encode query string parameters using the standard javascript function encodeURIComponent. According to the following test it is not the case:

describe('$http', function () {
 it('encodes uri components correctly', inject(function($http, $httpBackend) {
   var data = 'Hello from http://example.com';
   $httpBackend.expectGET('/api/process?data=' + encodeURIComponent(data));
   $http({ method: 'GET', url: '/api/process', params: { data: data } });
   $httpBackend.flush();
 }));
});

The test fails with the following error:

$http encodes uri components correctly
Error: Unexpected request: GET /api/process?data=Hello+from+http:%2F%2Fexample.com
Expected GET /api/process?data=Hello%20from%20http%3A%2F%2Fexample.com

To sum up:

Expected encoding: Hello%20from%20http%3A%2F%2Fexample.com
Actual encoding: Hello+from+http:%2F%2Fexample.com

What uri component (aka query string parameters) encoding method should I expect with AngularJS?

Solution

Angular (at least 1.3) doesn't only use encodeURIComponent and changes some replacements (like " " to "+").

this is the commit explaining why : https://github.com/angular/angular.js/commit/9e30baad3feafc82fb2f2011fd3f21909f4ba29e

And here's what you can see in 1.3 sources :

/**
 * This method is intended for encoding *key* or *value* parts of query component. We need a custom
 * method because encodeURIComponent is too aggressive and encodes stuff that doesn't have to be
 * encoded per http://tools.ietf.org/html/rfc3986:
 *    query       = *( pchar / "/" / "?" )
 *    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
 *    unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
 *    pct-encoded   = "%" HEXDIG HEXDIG
 *    sub-delims    = "!" / "$" / "&" / "'" / "(" / ")"
 *                     / "*" / "+" / "," / ";" / "="
 */
function encodeUriQuery(val, pctEncodeSpaces) {
  return encodeURIComponent(val).
             replace(/%40/gi, '@').
             replace(/%3A/gi, ':').
             replace(/%24/g, '$').
             replace(/%2C/gi, ',').
             replace(/%3B/gi, ';').
             replace(/%20/g, (pctEncodeSpaces ? '%20' : '+'));
}

note that pctEncodeSpaces is hardcoded to true;

Here's what you can do to decode URI parameters

decodeURIComponent(val.
             replace('@', '%40').
             replace(':', '%3A').
             replace('$', '%24').
             replace(',', '%2C').
             replace(';', '%3B').
             replace('+', '%20'));