feat(typings): expose CacheOptions type (#38)

* feat(typings): support for specifying key-value types

* chore: use `CacheOptions` name

README.md

@@ -253,6 +253,8 @@ LRU.forEach((value, key) => {
 You can set types for both keys and values. For example:
 
 ```ts
+import { createLRU } from 'lru.min';
+
 type Key = number;
 
 type Value = {
@@ -265,6 +267,31 @@ LRU.set(1, { name: 'Peter' });
 LRU.set(2, { name: 'Mary' });
 ```
 
+Also:
+
+```ts
+import { createLRU, type CacheOptions } from 'lru.min';
+
+type Key = number;
+
+type Value = {
+  name: string;
+};
+
+const options: CacheOptions<Key, Value> = {
+  max: 10,
+  onEviction(key, value) {
+    console.log(key, value);
+  },
+};
+
+// No need to repeat the type params
+const LRU = createLRU(options);
+
+LRU.set(1, { name: 'Peter' });
+LRU.set(2, { name: 'Mary' });
+```
+
 ---
 
 ### Performance

src/index.ts

@@ -1,9 +1,11 @@
-export const createLRU = <Key, Value>(options: {
+export type CacheOptions<Key = unknown, Value = unknown> = {
   /** Maximum number of items the cache can hold. */
   max: number;
   /** Function called when an item is evicted from the cache. */
   onEviction?: (key: Key, value: Value) => unknown;
-}) => {
+};
+
+export const createLRU = <Key, Value>(options: CacheOptions<Key, Value>) => {
   let { max, onEviction } = options;
 
   if (!(Number.isInteger(max) && max > 0))

test/quickstart.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, assert } from 'poku';
-import { createLRU } from '../src/index.ts';
+import { createLRU, type CacheOptions } from '../src/index.ts';
 
 describe('Quickstart example test', () => {
   it('Default', () => {
@@ -139,4 +139,61 @@ describe('Quickstart example test', () => {
       'Key "C" with value "Another Value" has been evicted.',
     ]);
   });
+
+  it('Type Test', () => {
+    const options: CacheOptions = {
+      max: 10,
+      onEviction(key, value) {
+        console.log(key, value);
+      },
+    };
+
+    createLRU(options);
+  });
+
+  it('Type Test: Params on `CacheOptions`', () => {
+    const options: CacheOptions<number, string> = {
+      max: 10,
+      onEviction(key, value) {
+        console.log(key, value);
+      },
+    };
+
+    createLRU(options).set(1, 'Test');
+    // @ts-expect-error
+    createLRU<number, string>(options).set('2', 'Test');
+  });
+
+  it('Type Test: Params in `createLRU`', () => {
+    const options: CacheOptions = {
+      max: 10,
+      onEviction(key, value) {
+        console.log(key, value);
+      },
+    };
+
+    createLRU<number, string>(options).set(1, 'Test');
+    // @ts-expect-error
+    createLRU<number, string>(options).set('2', 'Test');
+  });
+
+  it('Type Test: README.md', () => {
+    type Key = number;
+
+    type Value = {
+      name: string;
+    };
+
+    const options: CacheOptions<Key, Value> = {
+      max: 10,
+      onEviction(key, value) {
+        console.log(key, value);
+      },
+    };
+
+    const LRU = createLRU(options);
+
+    LRU.set(1, { name: 'Peter' });
+    LRU.set(2, { name: 'Mary' });
+  });
 });