Add tests to the lib

apps/block_scout_web/assets/__tests__/lib/async_listing_load.js

@@ -0,0 +1,80 @@
+import { asyncReducer, asyncInitialState } from '../../js/lib/async_listing_load'
+
+describe('ELEMENTS_LOAD', () => {
+  test('sets only nextPagePath and ignores other keys', () => {
+    const state = Object.assign({}, asyncInitialState)
+    const action = { type: 'ELEMENTS_LOAD', nextPagePath: 'set', foo: 1 }
+    const output = asyncReducer(state, action)
+
+    expect(output.foo).not.toEqual(1)
+    expect(output.nextPagePath).toEqual('set')
+  })
+})
+
+describe('ADD_ITEM_KEY', () => {
+  test('sets itemKey to what was passed in the action', () => {
+    const expectedItemKey = 'expected.Key'
+
+    const state = Object.assign({}, asyncInitialState)
+    const action = { type: 'ADD_ITEM_KEY', itemKey: expectedItemKey } 
+    const output = asyncReducer(state, action)
+
+    expect(output.itemKey).toEqual(expectedItemKey)
+  })
+})
+
+describe('START_REQUEST', () => {
+  test('sets loading status to true', () => {
+    const state = Object.assign({}, asyncInitialState, { loading: false })
+    const action = { type: 'START_REQUEST' } 
+    const output = asyncReducer(state, action)
+
+    expect(output.loading).toEqual(true)
+  })
+})
+
+describe('REQUEST_ERROR', () => {
+  test('sets requestError to true', () => {
+    const state = Object.assign({}, asyncInitialState, { requestError: false })
+    const action = { type: 'REQUEST_ERROR' } 
+    const output = asyncReducer(state, action)
+
+    expect(output.requestError).toEqual(true)
+  })
+})
+
+describe('FINISH_REQUEST', () => {
+  test('sets loading status to false', () => {
+    const state = Object.assign({}, asyncInitialState, {
+      loading: true,
+      loadingFirstPage: true
+    })
+    const action = { type: 'FINISH_REQUEST' } 
+    const output = asyncReducer(state, action)
+
+    expect(output.loading).toEqual(false)
+    expect(output.loadingFirstPage).toEqual(false)
+  })
+})
+
+describe('ITEMS_FETCHED', () => {
+  test('sets the items to what was passed in the action', () => {
+    const expectedItems = [1, 2, 3]
+
+    const state = Object.assign({}, asyncInitialState)
+    const action = { type: 'ITEMS_FETCHED', items: expectedItems } 
+    const output = asyncReducer(state, action)
+
+    expect(output.items).toEqual(expectedItems)
+  })
+})
+
+describe('NAVIGATE_TO_OLDER', () => {
+  test('sets beyondPageOne to true', () => {
+    const state = Object.assign({}, asyncInitialState, { beyondPageOne: false })
+    const action = { type: 'NAVIGATE_TO_OLDER' } 
+    const output = asyncReducer(state, action)
+
+    expect(output.beyondPageOne).toEqual(true)
+  })
+})