add tests to fetchManifest actions

package.json

@@ -32,6 +32,13 @@
     "eslint-plugin-jsx-a11y": "^6.0.3",
     "eslint-plugin-react": "^7.7.0",
     "jest": "^22.4.2",
+    "jest-fetch-mock": "^1.5.0",
+    "redux-mock-store": "^1.5.1",
     "webpack": "3.10.0"
+  },
+  "jest": {
+    "setupFiles": [
+      "./setupJest.js"
+    ]
   }
 }

setupJest.js

+// Setup Jest to mock fetch
+
+import fetch from 'jest-fetch-mock'; // eslint-disable-line import/no-extraneous-dependencies
+
+jest.setMock('node-fetch', fetch);
+global.fetch = require('jest-fetch-mock'); // eslint-disable-line import/no-extraneous-dependencies

tests/actions/index.test.js

+import configureMockStore from 'redux-mock-store';
+import thunk from 'redux-thunk';
+
 import * as actions from '../../actions/index';
 import ActionTypes from '../../action-types';
 
+const middlewares = [thunk];
+const mockStore = configureMockStore(middlewares);
 
 describe('actions', () => {
   describe('addWindow', () => {
@@ -80,4 +85,43 @@ describe('actions', () => {
       expect(actions.receiveManifest(id, json)).toEqual(expectedAction);
     });
   });
+  describe('fetchManifest', () => {
+    let store = null;
+    beforeEach(() => {
+      store = mockStore({});
+    });
+    describe('success response', () => {
+      beforeEach(() => {
+        fetch.mockResponseOnce(JSON.stringify({ data: '12345' })); // eslint-disable-line no-undef
+      });
+      it('dispatches the REQUEST_MANIFEST action', () => {
+        store.dispatch(actions.fetchManifest('https://purl.stanford.edu/sn904cj3429/iiif/manifest'));
+        expect(store.getActions()).toEqual([
+          { manifestId: 'https://purl.stanford.edu/sn904cj3429/iiif/manifest', type: 'REQUEST_MANIFEST' },
+        ]);
+      });
+      it('dispatches the REQUEST_MANIFEST and then RECEIVE_MANIFEST', () => {
+        store.dispatch(actions.fetchManifest('https://purl.stanford.edu/sn904cj3429/iiif/manifest'))
+          .then(() => {
+            const expectedActions = store.getActions();
+            expect(expectedActions).toEqual([
+              { manifestId: 'https://purl.stanford.edu/sn904cj3429/iiif/manifest', type: 'REQUEST_MANIFEST' },
+              { manifestId: 'https://purl.stanford.edu/sn904cj3429/iiif/manifest', manifestJson: { data: '12345' }, type: 'RECEIVE_MANIFEST' },
+            ]);
+          });
+      });
+    });
+    describe('error response', () => {
+      it('dispatches the REQUEST_MANIFEST and then RECEIVE_MANIFEST', () => {
+        store.dispatch(actions.fetchManifest('https://purl.stanford.edu/sn904cj3429/iiif/manifest'))
+          .then(() => {
+            const expectedActions = store.getActions();
+            expect(expectedActions).toEqual([
+              { manifestId: 'https://purl.stanford.edu/sn904cj3429/iiif/manifest', type: 'REQUEST_MANIFEST' },
+              { manifestId: 'https://purl.stanford.edu/sn904cj3429/iiif/manifest', error: new Error('invalid json response body at undefined reason: Unexpected end of JSON input'), type: 'RECEIVE_MANIFEST_FAILURE' },
+            ]);
+          });
+      });
+    });
+  });
 });