Unexpected Request Error with $HttpBackend (AngularJS)

I am using HttpBackend to mock some Http responses for some calls that my Angular app is making.

However, I am getting the error "Unexpected Request: [object Object] undefined".

I know that usually this error means you're missing or mistyped one of the $http requests that the app makes so it can't find a response. But my error is not specific like the other ones which usually say like "Unexpected Request: GET api/call" so I don't know what is wrong.

Has anyone ever encountered this specific error before?

Sample Code

angular controller:

app.controller( 'ctrl', 
   [ '$scope' , '$http' , '$location', function( $scope, $http, $location ) {
        $http.get(
            "/api/1.0/id/" + id, 
            {
                headers: getAuthHeaders()
            }
        ).success(function( data ){ //... })]
);

jasmine test:

it('should ...', function(){
  httpBackend.whenGET('/api/1.0/id/*').respond(200,{"test":"Test"});
  //...
});