diff --git a/src/testUtils/noDigestPromises.js b/src/testUtils/noDigestPromises.js
index a86d7333adc2..4b57a52f0ace 100644
--- a/src/testUtils/noDigestPromises.js
+++ b/src/testUtils/noDigestPromises.js
@@ -1,6 +1,8 @@
 var Bluebird = require('bluebird');
 require('ui/promises');
 
+Bluebird.longStackTraces();
+
 /**
  * replace the Promise service with Bluebird so that tests
  * can use promises without having to call $rootScope.apply()
diff --git a/src/ui/public/courier/fetch/__tests__/fetch.js b/src/ui/public/courier/fetch/__tests__/fetch.js
new file mode 100644
index 000000000000..82ba398805c9
--- /dev/null
+++ b/src/ui/public/courier/fetch/__tests__/fetch.js
@@ -0,0 +1,73 @@
+import ngMock from 'ngMock';
+import expect from 'expect.js';
+import sinon from 'auto-release-sinon';
+
+import FetchProvider from 'ui/courier/fetch';
+import IndexPatternProvider from 'fixtures/stubbed_logstash_index_pattern';
+import searchResp from 'fixtures/search_response';
+
+describe('Fetch service', function () {
+  require('testUtils/noDigestPromises').activateForSuite();
+
+  let es;
+  let fetch;
+  let Promise;
+  let DocSource;
+  let SearchSource;
+  let indexPattern;
+
+  beforeEach(ngMock.module('kibana'));
+  beforeEach(ngMock.inject(function ($injector, Private) {
+    es = $injector.get('es');
+    Promise = $injector.get('Promise');
+    fetch = Private(FetchProvider);
+    indexPattern = Private(IndexPatternProvider);
+    DocSource = Private(require('ui/courier/data_source/doc_source'));
+    SearchSource = Private(require('ui/courier/data_source/search_source'));
+  }));
+
+  describe('#doc(docSource)', function () {
+    it('fetches a single doc source', function () {
+      const doc = {
+        _index: 'test-index',
+        _type: 'test-type',
+        _id: 'test-id',
+      };
+
+      const source = new DocSource({
+        index: doc._index,
+        type: doc._type,
+        id: doc._id
+      });
+
+      sinon.stub(es, 'mget').returns(Promise.resolve({
+        docs: [doc]
+      }));
+
+      return fetch.doc(source).then(function (resp) {
+        expect(resp).to.be(doc);
+      });
+    });
+  });
+
+  describe('#search(searchSource)', function () {
+    it('fetches a single search source', function () {
+      const resp = searchResp;
+      const mresp = {
+        responses: [resp]
+      };
+
+      const source = new SearchSource({
+        index: indexPattern
+      });
+
+      sinon.stub(es, 'msearch').returns(Promise.resolve(mresp));
+
+      return fetch
+      .search(source)
+      .then(function (courierResp) {
+        expect(courierResp).to.be(resp);
+      });
+    });
+  });
+});
diff --git a/src/ui/public/courier/fetch/_call_client.js b/src/ui/public/courier/fetch/_call_client.js
index d30893cbb47e..1cec794512c3 100644
--- a/src/ui/public/courier/fetch/_call_client.js
+++ b/src/ui/public/courier/fetch/_call_client.js
@@ -33,7 +33,10 @@ define(function (require) {
               return responses[_.findIndex(executable, req)];
           }
         })
-        .then(defer.resolve, defer.reject);
+        .then(
+          (res) => defer.resolve(res),
+          (err) => defer.reject(err)
+        );
       };
 
 
diff --git a/src/ui/public/courier/fetch/fetch.js b/src/ui/public/courier/fetch/fetch.js
index dc67bcd6691c..03ce8199aa43 100644
--- a/src/ui/public/courier/fetch/fetch.js
+++ b/src/ui/public/courier/fetch/fetch.js
@@ -20,7 +20,7 @@ define(function (require) {
       var defer = Promise.defer();
 
       fetchThese([
-        source._createRequest(defer.resolve)
+        source._createRequest(defer)
       ]);
 
       return defer.promise;