1.4.5 $http transformResponse property isn't fired when status code is 204 (No Content)

[kvernon]

I keep wanting to use the transform response property of the config object with an http service wrapper. The docs claim that the transformResponse is fired when there is a successful status message. Instead, I get no transformResponse firing.

I have tests that show OK, 200, works, but 204 with null or undefined data does not.

The reason why is I'd like to set up default data, but I cannot with this current behavior (I took out a few things, but this should get the gist:

describe("When using the SubNavServiceUri", function() {
    var serviceUri;
    var requestUri = "/api/aliens";
    var collection = null;
    var httpBackend;

    beforeEach(function () {
        module("superSiteApp");

        inject(function (_$httpBackend_, _SubNavServiceUri_) {
            httpBackend = _$httpBackend_;

            serviceUri = _SubNavServiceUri_;
        });
    });

    afterEach(function () {
        httpBackend.verifyNoOutstandingExpectation();
        httpBackend.verifyNoOutstandingRequest();
    });

it("and NoContent it should return empty collection", function () {
        // set up correct end point
        httpBackend
            .expectGET(requestUri)
            .respond(HttpStatusCode.NoContent);

        var actual;

        serviceUri.get(requestUri).then(function (result) {
            actual = result.data;
        });

        httpBackend.flush();

        expect([]).toEqual(actual);
        expect(0).toEqual(actual.length);
    });


...
service("SubNavServiceUri", ["$http", function ($http) {
        var isNullOrUndefined = function(item) {
            return item === null || item === undefined;
        };

        var transformData = function(data) {
            var result = [];
            return result;
        };

        var get = function(uri) {
            var object = {
                cache: false,
                transformResponse: function (data, headersGetter, status) {
                    console.log("howdy ");
                    console.log("headersGetter " + headersGetter);
                    console.log("status " + status);
                    if (isNullOrUndefined(data)) {
                        return [];
                    } else {
                        return transformData(data);
                    }
                }
            };

            return $http.get(uri, object);
        };

        return {
            "get": get
        };
...

[gkalpak]

This isn't (directly) related to the status code, but to the response data. Namely, transformResponse is skipped if response.data is falsy (see http.js#L1002-L1006).

A little background

This wasn't always the case. The distinction was first introduced in 6e4955a and only affected HEAD requests, which makes sense, since HEAD requests have no body.

Then, in 9ba24c5 it was changed to apply to all requests with an empty response body, in order to "allow empty json response" (when the the content-type is application/json).

I believe this is a bug. Furthermore, with the changes introduced in 6f19a6f and b9bdbe6, defaultHttpResponseTranform() is now able to ignore empty JSON responses.
So, I believe that the changes in 9ba24c5 can (and should) be reverted.