diff --git a/src/selectors/shared.test.js b/src/selectors/shared.test.js
new file mode 100644
index 00000000..172761cd
--- /dev/null
+++ b/src/selectors/shared.test.js
@@ -0,0 +1,118 @@
+import { List, Map } from 'immutable'
+
+import {
+  createImmutableSelector,
+  createImmutableSelectorCreator,
+  getKeysFromImmutableObject,
+  immutableMemoize,
+  objectKeysMemoized,
+} from './shared'
+
+const obj = Map({
+  a: 10,
+  b: 20,
+  c: 30,
+})
+
+test('getKeysFromImmutableObject', () => {
+  expect(getKeysFromImmutableObject(obj)).toEqual(List(['a', 'b', 'c']))
+})
+
+test('objectKeysMemoized', () => {
+  const result1 = objectKeysMemoized(obj)
+  const result2 = objectKeysMemoized(obj)
+
+  expect(result1).toEqual(List(['a', 'b', 'c']))
+  expect(result1).toBe(result2)
+})
+
+test('immutableMemoize -- memoize all arguments', () => {
+  const fn = immutableMemoize((a, b, c) => Map({ aa: a, bb: b, cc: c }))
+
+  const result1 = fn(10, 20, 30)
+  const result2 = fn(10, 20, 30)
+  const result3 = fn(10, 20, 33)
+
+  expect(result1).toEqual(Map({ aa: 10, bb: 20, cc: 30 }))
+  expect(result1).toBe(result2)
+  expect(result1).not.toBe(result3)
+})
+
+test('immutableMemoize -- only check first two arguments', () => {
+  const fn = immutableMemoize(
+    (a, b, c) => Map({ aa: a, bb: b, cc: c }),
+    undefined,
+    2,
+  )
+
+  const result1 = fn(10, 20, 30)
+  const result2 = fn(10, 20, 30)
+  const result3 = fn(10, 20, 33)
+  const result4 = fn(10, 22, 30)
+
+  expect(result1).toEqual(Map({ aa: 10, bb: 20, cc: 30 }))
+  expect(result1).toBe(result2)
+  expect(result1).toBe(result3)
+  expect(result1).not.toBe(result4)
+})
+
+test('createImmutableSelector', () => {
+  const immutableSelector = createImmutableSelector(
+    (state, params) => params.get('a') + 1,
+    (state, params) => params.get('b') + 2,
+    (state, params) => params.get('c') + 3,
+    (a, b, c) => Map({ a, b, c }),
+  )
+
+  const result1 = immutableSelector(null, obj)
+  const result2 = immutableSelector(null, obj)
+
+  expect(result1).toEqual(Map({ a: 11, b: 22, c: 33 }))
+  expect(result1).toBe(result2)
+})
+
+test('createImmutableSelectorCreator -- memoize all arguments', () => {
+  const _createImmutableSelector1 = createImmutableSelectorCreator()
+  const _createImmutableSelector2 = createImmutableSelectorCreator()
+
+  const immutableSelector1 = _createImmutableSelector1(
+    (state, params) => params.get('a') + 1,
+    (state, params) => params.get('b') + 2,
+    (state, params) => params.get('c') + 3,
+    (a, b, c) => Map({ a, b, c }),
+  )
+
+  const immutableSelector2 = _createImmutableSelector2(
+    (state, params) => params.get('a') + 1,
+    (state, params) => params.get('b') + 2,
+    (state, params) => params.get('c') + 3,
+    (a, b, c) => Map({ a, b, c }),
+  )
+
+  const result1 = immutableSelector1(null, obj)
+  const result2 = immutableSelector1(null, obj)
+  const result3 = immutableSelector2(null, obj)
+
+  expect(result1).toEqual(Map({ a: 11, b: 22, c: 33 }))
+  expect(result1).toBe(result2)
+  expect(result1).not.toBe(result3)
+})
+
+test('createImmutableSelectorCreator -- only check two arguments', () => {
+  const _createImmutableSelector = createImmutableSelectorCreator(2)
+
+  const immutableSelector = _createImmutableSelector(
+    (state, params) => params.get('a') + 1,
+    (state, params) => params.get('b') + 2,
+    (state, params) => params.get('c') + 3,
+    (a, b, c) => Map({ a, b, c }),
+  )
+
+  const result1 = immutableSelector(null, Map({ a: 10, b: 20, c: 30 }))
+  const result2 = immutableSelector(null, Map({ a: 10, b: 20, c: 33 }))
+  const result3 = immutableSelector(null, Map({ a: 10, b: 22, c: 30 }))
+
+  expect(result1).toEqual(Map({ a: 11, b: 22, c: 33 }))
+  expect(result1).toBe(result2)
+  expect(result1).not.toBe(result3)
+})