diff --git a/web/src/js/__tests__/ducks/utils/storeSpec.js b/web/src/js/__tests__/ducks/utils/storeSpec.js
new file mode 100644
index 000000000..6bfea2c79
--- /dev/null
+++ b/web/src/js/__tests__/ducks/utils/storeSpec.js
@@ -0,0 +1,86 @@
+jest.unmock('../../../ducks/utils/store')
+
+import reduceStore, * as storeActions from '../../../ducks/utils/store'
+
+describe('store reducer', () => {
+    it('should return initial state', () => {
+        expect(reduceStore(undefined, {})).toEqual({
+            byId: {},
+            list: [],
+            listIndex: {},
+            view: [],
+            viewIndex: {},
+        })
+    })
+
+    it('should handle add action', () => {
+        let a = {id: 1},
+            b = {id: 9},
+            state = reduceStore(undefined, {})
+        expect(state = reduceStore(state, storeActions.add(a))).toEqual({
+                byId: { 1: a },
+                listIndex: { 1: 0 },
+                list: [ a ],
+                view: [ a ],
+                viewIndex: { 1: 0 },
+        })
+
+        expect(reduceStore(state, storeActions.add(b))).toEqual({
+            byId: { 1: a, 9: b },
+            listIndex: { 1: 0, 9: 1 },
+            list: [ a, b ],
+            view: [ a, b ],
+            viewIndex: { 1: 0, 9: 1 },
+        })
+    })
+
+    it('should not add the item with duplicated id', () => {
+        let a = {id: 1},
+            state = reduceStore(undefined, storeActions.add(a))
+        expect(reduceStore(state, storeActions.add(a))).toEqual(state)
+    })
+
+    it('should handle update action', () => {
+        let a = {id: 1, foo: "foo"},
+            updated = {...a, foo: "bar"},
+            state = reduceStore(undefined, storeActions.add(a))
+        expect(reduceStore(state, storeActions.update(updated))).toEqual({
+            byId: { 1: updated },
+            list: [ updated ],
+            listIndex: { 1: 0 },
+            view: [ updated ],
+            viewIndex: { 1: 0 },
+        })
+    })
+
+    it('should handle update action with filter', () => {
+        let a = {id: 0},
+            b = {id: 1},
+            state = reduceStore(undefined, storeActions.add(a))
+        state = reduceStore(state, storeActions.add(b))
+        expect(reduceStore(state, storeActions.update(b,
+            item => {return item.id < 1}))).toEqual({
+                byId: { 0: a, 1: b },
+                list: [ a, b ],
+                listIndex: { 0: 0, 1: 1 },
+                view: [ a ],
+                viewIndex: { 0: 0 }
+        })
+    })
+
+    it('should handle update action with sort', () => {
+        let a = {id: 2},
+            b = {id: 3},
+            state = reduceStore(undefined, storeActions.add(a))
+        state = reduceStore(state, storeActions.add(b))
+        expect(reduceStore(state, storeActions.update(a, undefined,
+            (a, b) => {return b.id - a.id}))).toEqual({
+                // sort by id in descending order
+                byId: { 2: a, 3: b },
+                list: [ a, b ],
+                listIndex: {2: 0, 3: 1},
+                view: [ b, a ],
+                viewIndex: { 2: 1, 3: 0 },
+        })
+    })
+})