Add type tests

effector · Dec 14, 2023 · 5d34745 · 5d34745
1 parent a8abce3
commit 5d34745
Showing 1 changed file with 34 additions and 0 deletions.
diff --git a/test-typings/previous-value.ts b/test-typings/previous-value.ts
@@ -0,0 +1,34 @@
+import { expectType } from 'tsd';
+import { Store, createStore, createEvent } from 'effector';
+import { previousValue } from '../dist/previous-value';
+
+{
+  const $foo = createStore('a');
+  const $fooPrev = previousValue($foo);
+
+  expectType<Store<string | null>>($fooPrev);
+}
+{
+  const $foo = createStore('a');
+  const $fooPrev = previousValue($foo, 'b');
+
+  expectType<Store<string>>($fooPrev);
+}
+{
+  const $foo = createStore('a');
+  const $fooPrev = previousValue($foo, 0);
+
+  expectType<Store<string | number>>($fooPrev);
+}
+{
+  const $foo = createStore('a');
+  const $fooPrev = previousValue($foo, undefined);
+
+  expectType<Store<string | void>>($fooPrev);
+}
+{
+  const foo = createEvent();
+
+  // @ts-expect-error
+  previousValue(foo, 0);
+}