Add delMany (#130)

Author: peterpeterparker

README.md

@@ -166,6 +166,26 @@ import { del } from 'idb-keyval';
 del('hello');
 ```
 
+### delMany:
+
+Delete many keys at once. This is faster than calling `del` multiple times.
+
+```js
+import { del, delMany } from 'idb-keyval';
+
+// Instead of:
+Promise.all([del(123), del('hello')])
+  .then(() => console.log('It worked!'))
+  .catch((err) => console.log('It failed!', err));
+
+// It's faster to do:
+delMany([
+  123, 'hello'
+])
+  .then(() => console.log('It worked!'))
+  .catch((err) => console.log('It failed!', err));
+```
+
 ### clear:
 
 Clear all values in the store.

src/index.ts

@@ -148,6 +148,22 @@ export function del(
   });
 }
 
+/**
+ * Delete multiple keys at once.
+ *
+ * @param keys List of keys to delete.
+ * @param customStore Method to get a custom store. Use with caution (see the docs).
+ */
+export function delMany(
+  keys: IDBValidKey[],
+  customStore = defaultGetStore(),
+): Promise<void> {
+  return customStore('readwrite', (store: IDBObjectStore) => {
+    keys.forEach((key: IDBValidKey) => store.delete(key));
+    return promisifyRequest(store.transaction);
+  });
+}
+
 /**
  * Clear all values in the store.
  *

test/index.ts

@@ -13,6 +13,7 @@ import {
   setMany,
   update,
   getMany,
+  delMany
 } from '../src';
 import { assert as typeAssert, IsExact } from 'conditional-type-checks';
 
@@ -481,5 +482,74 @@ mocha.setup('tdd');
     });
   });
 
+  suite('delMany', () => {
+    setup(() => Promise.all([clear(), clear(customStore)]));
+
+    test('basics', async () => {
+      await setMany([
+        ['foo', 'bar'],
+        [123, '456'],
+        ['hello', 'world'],
+      ]);
+
+      await delMany(['foo', 123, 'hello']);
+
+      assert.deepEqual(
+        await getMany(['foo', 123, 'hello']),
+        [undefined, undefined, undefined],
+        `Keys have been deleted`,
+      );
+    });
+
+    test('delete selected keys', async () => {
+      await setMany([
+        ['foo', 'bar'],
+        [123, '456'],
+        ['hello', 'world'],
+      ]);
+
+      await delMany(['foo', 123, 'does-not-exist']);
+
+      assert.deepEqual(
+        await getMany(['foo', 123, 'hello']),
+        [undefined, undefined, 'world'],
+        `Selected keys appear to have been deleted`,
+      );
+    });
+
+    test('custom store', async () => {
+      await setMany([
+        ['foo', 'bar'],
+        [123, '456'],
+      ]);
+      await setMany(
+        [
+          ['hello', 'world'],
+          [456, '789'],
+          [1122, '3344']
+        ],
+        customStore,
+      );
+
+      await delMany(['hello', 456], customStore)
+
+      assert.deepEqual(
+        await entries(),
+        [
+          [123, '456'],
+          ['foo', 'bar'],
+        ],
+        `Still got entries`,
+      );
+      assert.deepEqual(
+        await entries(customStore),
+        [
+          [1122, '3344']
+        ],
+        `Selected custom store keys have been deleted`,
+      );
+    });
+  });
+
   mocha.run();
 })();