can add actions via addEffect

src/Updux.ts

@@ -270,7 +270,9 @@ export default class Updux<D extends DuxConfig> {
     addEffect<AC extends rtk.ActionCreatorWithPreparedPayload<any, any, string, never, never>>(
         actionCreator: AC,
         effect: EffectMiddleware<D, ReturnType<AC>>,
-    ): Updux<D>;
+    ): Updux<D & {
+        actions: Record<AC extends { type: infer T } ? T : never, AC>
+    }>;
     addEffect(
         guardFunc: (action: AnyAction) => boolean,
         effect: EffectMiddleware<D>,
@@ -292,6 +294,9 @@ export default class Updux<D extends DuxConfig> {
                 }
             }
 
+            if (!this.actions[actionCreator.type])
+                this.addAction(actionCreator);
+
             const test = actionCreator.hasOwnProperty('match')
                 ? actionCreator.match
                 : actionCreator;

src/effects.test.ts

@@ -2,7 +2,7 @@ import { test, expect } from 'vitest';
 import Updux from './Updux.js';
 import { buildEffectsMiddleware } from './effects.js';
 import { createAction, withPayload } from './index.js';
-import { AnyAction, Dispatch } from '@reduxjs/toolkit';
+import { ActionCreator, AnyAction, Dispatch } from '@reduxjs/toolkit';
 import { AugmentedMiddlewareAPI } from './types.js';
 
 test('addEffect signatures', () => {
@@ -221,5 +221,19 @@ test('catchall addEffect', () => {
     expect(spy).toHaveBeenCalled();
 });
 
+test('addEffect with unknown actionCreator adds it', () => {
+    const foo = createAction('foo');
+    const dux = new Updux({}).addEffect(
+        foo, () => () => () => { }
+    );
+
+    expectTypeOf(dux.actions.foo).toMatchTypeOf<
+        ActionCreator<any>
+    >();
+
+    expect(dux.actions.foo()).toMatchObject({ type: 'foo' });
+
+});
+
 // TODO subdux effects
 // TODO allow to subscribe / unsubscribe effects?

src/mutations.test.ts

@@ -1,5 +1,6 @@
 import { createAction } from '@reduxjs/toolkit';
 import { test, expect } from 'vitest';
+import { withPayload } from './actions.js';
 import Updux from './Updux.js';
 
 test('set a mutation', () => {
@@ -110,3 +111,14 @@ test('setDefaultMutation return value', () => {
 
     expectTypeOf(withDM.initialState).toBeNumber();
 });
+
+test('addMutation with createAction', () => {
+    const setName = createAction('setName', withPayload<string>());
+
+    const dux = new Updux({
+        initialState: {
+            name: '',
+            round: 1,
+        },
+    }).addMutation(setName, (name) => (state) => ({ ...state, name }));
+});