This is the damned code I copied without much thinking:
$httpProvider.interceptors.push(function($q, dependency1, dependency2) {
return {
'request': function(config) {
// same as above
},
'response': function(response) {
// same as above
}
};
});
The problem (obviously) was that the function inside the push had 2 example parameters - "dependency1, dependency2", after removing them everything was working again.
Hope this could help someone as tired as me trying to search for that error message instead of reading it.