enhance: Move NetworkManager not found detection to applyManager()

Author: ntucker

.changeset/spotty-pumpkins-explain.md

@@ -0,0 +1,6 @@
+---
+'@data-client/core': patch
+'@data-client/react': patch
+---
+
+Move NetworkManager missing detection to initialization (applyManager())

packages/core/src/manager/__tests__/applyManager.ts

@@ -0,0 +1,38 @@
+import Controller from '../../controller/Controller';
+import applyManager from '../applyManager';
+import NetworkManager from '../NetworkManager';
+
+function onError(e: any) {
+  e.preventDefault();
+}
+beforeEach(() => {
+  if (typeof addEventListener === 'function')
+    addEventListener('error', onError);
+});
+afterEach(() => {
+  if (typeof removeEventListener === 'function')
+    removeEventListener('error', onError);
+});
+
+it('applyManagers should console.warn() when no NetworkManager is provided', () => {
+  const warnspy = jest
+    .spyOn(global.console, 'warn')
+    .mockImplementation(() => {});
+  try {
+    applyManager([], new Controller());
+    expect(warnspy.mock.calls.length).toBe(2);
+  } finally {
+    warnspy.mockRestore();
+  }
+});
+it('applyManagers should not console.warn() when NetworkManager is provided', () => {
+  const warnspy = jest
+    .spyOn(global.console, 'warn')
+    .mockImplementation(() => {});
+  try {
+    applyManager([new NetworkManager()], new Controller());
+    expect(warnspy.mock.calls.length).toBe(0);
+  } finally {
+    warnspy.mockRestore();
+  }
+});

packages/core/src/manager/applyManager.ts

@@ -1,3 +1,4 @@
+import NetworkManager from './NetworkManager.js';
 import type Controller from '../controller/Controller.js';
 import type { Reducer, Dispatch, ReducerState } from '../middlewareTypes.js';
 import { Manager } from '../types.js';
@@ -6,6 +7,16 @@ export default function applyManager(
   managers: Manager[],
   controller: Controller,
 ): Middleware[] {
+  /* istanbul ignore next */
+  if (
+    process.env.NODE_ENV !== 'production' &&
+    !managers.find(mgr => mgr instanceof NetworkManager)
+  ) {
+    console.warn('NetworkManager not found; this is a required manager.');
+    console.warn(
+      'See https://dataclient.io/docs/guides/redux for hooking up redux',
+    );
+  }
   return managers.map((manager, i) => {
     const middleware = manager.getMiddleware();
     return ({ dispatch, getState }) => {

packages/core/src/state/__tests__/reducer.ts

@@ -595,7 +595,7 @@ describe('reducer', () => {
     const newState = reducer(iniState, action);
     expect(newState.entities).toBe(iniState.entities);
   });
-  it('rdc/fetch should console.warn()', () => {
+  it('rdc/fetch should not console.warn()', () => {
     const warnspy = jest
       .spyOn(global.console, 'warn')
       .mockImplementation(() => {});
@@ -618,7 +618,8 @@ describe('reducer', () => {
       };
       const newState = reducer(iniState, action);
       expect(newState).toBe(iniState);
-      expect(warnspy.mock.calls.length).toBe(2);
+      // moved warns to applyManager() vv
+      expect(warnspy.mock.calls.length).toBe(0);
     } finally {
       warnspy.mockRestore();
     }

packages/core/src/state/reducer/fetchReducer.ts

@@ -12,18 +12,6 @@ export function fetchReducer(state: State<unknown>, action: FetchAction) {
       ...state,
       optimistic: [...state.optimistic, setAction],
     };
-  } else {
-    // If 'fetch' action reaches the reducer there are no middlewares installed to handle it
-    /* istanbul ignore next */
-    if (process.env.NODE_ENV !== 'production') {
-      console.warn(
-        'Fetch appears unhandled - you are likely missing the NetworkManager middleware',
-      );
-      console.warn(
-        'See https://dataclient.io/docs/guides/redux for hooking up redux',
-      );
-    }
-
-    return state;
   }
+  return state;
 }