Merge pull request #232 from effector/fix-and-or-simple-store

src/and/and.fork.test.ts

@@ -35,3 +35,13 @@ test('When at least one store has falsy value result must be false', async () =>
   `);
   expect(scope.getState($result)).toBe(false);
 });
+
+test('Returns boolean value for single store', async () => {
+  const $storeOne = createStore('hello');
+
+  const $andIncorrect = and($storeOne);
+
+  const scope = fork();
+
+  expect(scope.getState($andIncorrect)).toBe(true);
+});

src/and/index.ts

@@ -2,6 +2,9 @@ import { combine, Store } from 'effector';
 
 export function and(...stores: Array<Store<any>>): Store<boolean> {
   return combine(stores, (values) =>
-    values.reduce((all, current) => Boolean(all) && Boolean(current)),
+    values.reduce(
+      (all, current) => Boolean(all) && Boolean(current),
+      Boolean(values[0]),
+    ),
   ) as Store<boolean>;
 }

src/or/index.ts

@@ -2,6 +2,9 @@ import { combine, Store } from 'effector';
 
 export function or(...stores: Array<Store<any>>): Store<boolean> {
   return combine(stores, (values) =>
-    values.reduce((all, current) => Boolean(all) || Boolean(current)),
+    values.reduce(
+      (all, current) => Boolean(all) || Boolean(current),
+      Boolean(values[0]),
+    ),
   ) as Store<boolean>;
 }

src/or/or.fork.test.ts

@@ -35,3 +35,13 @@ it('should be true when at least one store has truthy value', async () => {
   `);
   expect(scope.getState($result)).toBe(true);
 });
+
+test('Returns boolean value for single store', async () => {
+  const $storeOne = createStore('hello');
+
+  const $andIncorrect = or($storeOne);
+
+  const scope = fork();
+
+  expect(scope.getState($andIncorrect)).toBe(true);
+});