fix(core): CHECKOUT-2450 Create new observable from observable-like a…

…ction

README.md

@@ -20,9 +20,9 @@ npm install --save @bigcommerce/data-store
 
 ## Requirements
 
-This library depends on [rxjs](https://github.com/ReactiveX/rxjs). Please refer to [package.json](package.json) for the version requirement.
+This library requires [Promise polyfill](https://github.com/stefanpenner/es6-promise) if you need to support older browsers, such as IE11.
 
-It also requires [Promise polyfill](https://github.com/stefanpenner/es6-promise) if you need to support older browsers, such as IE11.
+You may need to create Observables when using this library (please refer to the usage section). We recommend you to use [rxjs](https://github.com/ReactiveX/rxjs) until the time comes when you can create them natively.
 
 
 ## Usage

package.json

@@ -35,18 +35,15 @@
     "validate-commits": "validate-commits",
     "validate-dependencies": "yarn install --check-files --frozen-lockfile"
   },
-  "peerDependencies": {
-    "rxjs": "^5.5.5"
-  },
   "dependencies": {
     "@types/lodash": "^4.14.92",
     "lodash": "^4.17.4",
+    "rxjs": "^5.5.5",
     "tslib": "^1.8.0"
   },
   "devDependencies": {
     "@types/jest": "^21.1.10",
     "jest": "^21.2.1",
-    "rxjs": "^5.5.5",
     "standard-version": "^4.2.0",
     "ts-jest": "^21.2.3",
     "tslint": "^5.9.1",

src/data-store.ts

@@ -1,15 +1,17 @@
 import { isEqual, merge } from 'lodash';
 import { BehaviorSubject } from 'rxjs/BehaviorSubject';
-import { Observable } from 'rxjs/Observable';
+import { Observable, SubscribableOrPromise } from 'rxjs/Observable';
 import { Subject } from 'rxjs/Subject';
 import Action from './action';
 import deepFreeze from './deep-freeze';
-import DispatchableDataStore, { DispatchOptions } from './dispatchable-data-store';
+import DispatchableDataStore, { DispatchableAction, DispatchOptions } from './dispatchable-data-store';
+import isObservableActionLike from './is-observable-action-like';
 import noopActionTransformer from './noop-action-transformer';
 import noopStateTransformer from './noop-state-transformer';
 import ReadableDataStore, { Filter, Subscriber, Unsubscriber } from './readable-data-store';
 import Reducer from './reducer';
 import ThunkAction from './thunk-action';
+import 'rxjs/add/observable/from';
 import 'rxjs/add/observable/merge';
 import 'rxjs/add/observable/of';
 import 'rxjs/add/observable/throw';
@@ -65,11 +67,11 @@ export default class DataStore<TState, TAction extends Action = Action, TTransfo
     }
 
     dispatch<TDispatchAction extends TAction>(
-        action: TDispatchAction | Observable<TDispatchAction> | ThunkAction<TDispatchAction, TTransformedState>,
+        action: DispatchableAction<TDispatchAction, TTransformedState>,
         options?: DispatchOptions
     ): Promise<TTransformedState> {
-        if (action instanceof Observable) {
-            return this._dispatchObservableAction(action, options);
+        if (isObservableActionLike(action)) {
+            return this._dispatchObservableAction(Observable.from(action), options);
         }
 
         if (typeof action === 'function') {

src/dispatchable-data-store.ts

@@ -1,14 +1,17 @@
-import { Observable } from 'rxjs/Observable';
+import { SubscribableOrPromise } from 'rxjs/Observable';
 import Action from './action';
+import ThunkAction from './thunk-action';
 import ReadableDataStore from './readable-data-store';
 
 export default interface DispatchableDataStore<TTransformedState, TAction extends Action> extends ReadableDataStore<TTransformedState> {
     dispatch: <TDispatchAction extends TAction>(
-        action: TDispatchAction | Observable<TDispatchAction>,
+        action: DispatchableAction<TDispatchAction, TTransformedState>,
         options?: DispatchOptions
     ) => Promise<TTransformedState>;
 }
 
 export interface DispatchOptions {
     queueId?: string;
 }
+
+export type DispatchableAction<TAction = Action, TState = any> = TAction | SubscribableOrPromise<TAction> | ThunkAction<TAction, TState>;

src/is-observable-action-like.spec.ts

@@ -0,0 +1,20 @@
+import { Observable } from 'rxjs';
+import createAction from './create-action';
+import isObservableActionLike from './is-observable-action-like';
+
+describe('isObservableActionLike()', () => {
+    it('returns true if observable action', () => {
+        expect(isObservableActionLike(Observable.of(createAction('FOOBAR'))))
+            .toEqual(true);
+    });
+
+    it('returns true if promise-like action', () => {
+        expect(isObservableActionLike(Promise.resolve(createAction('FOOBAR'))))
+            .toEqual(true);
+    });
+
+    it('returns false if not observable action or promise-like action', () => {
+        expect(isObservableActionLike(createAction('FOOBAR')))
+            .toEqual(false);
+    });
+});

src/is-observable-action-like.ts

@@ -0,0 +1,12 @@
+import { Subscribable, SubscribableOrPromise } from 'rxjs/Observable';
+import { DispatchableAction } from './dispatchable-data-store';
+import Action from './action';
+
+export default function isObservableActionLike<TAction extends Action = Action>(
+    action: DispatchableAction<TAction>
+): action is SubscribableOrPromise<TAction> {
+    return (
+        typeof (action as Subscribable<TAction>).subscribe === 'function' ||
+        typeof (action as PromiseLike<TAction>).then === 'function'
+    );
+}