diff --git a/src/tags.test.ts b/src/tags.test.ts
deleted file mode 100644
index e49d31a..0000000
--- a/src/tags.test.ts
+++ /dev/null
@@ -1,25 +0,0 @@
-import { assertEquals } from '@std/assert';
-
-import { addTag, deleteTag, getTagSet } from './tags.ts';
-
-Deno.test('getTagSet', () => {
-  assertEquals(getTagSet([], 'p'), new Set());
-  assertEquals(getTagSet([['p', '123']], 'p'), new Set(['123']));
-  assertEquals(getTagSet([['p', '123'], ['p', '456']], 'p'), new Set(['123', '456']));
-  assertEquals(getTagSet([['p', '123'], ['p', '456'], ['q', '789']], 'p'), new Set(['123', '456']));
-});
-
-Deno.test('addTag', () => {
-  assertEquals(addTag([], ['p', '123']), [['p', '123']]);
-  assertEquals(addTag([['p', '123']], ['p', '123']), [['p', '123']]);
-  assertEquals(addTag([['p', '123'], ['p', '456']], ['p', '123']), [['p', '123'], ['p', '456']]);
-  assertEquals(addTag([['p', '123'], ['p', '456']], ['p', '789']), [['p', '123'], ['p', '456'], ['p', '789']]);
-});
-
-Deno.test('deleteTag', () => {
-  assertEquals(deleteTag([], ['p', '123']), []);
-  assertEquals(deleteTag([['p', '123']], ['p', '123']), []);
-  assertEquals(deleteTag([['p', '123']], ['p', '456']), [['p', '123']]);
-  assertEquals(deleteTag([['p', '123'], ['p', '123']], ['p', '123']), []);
-  assertEquals(deleteTag([['p', '123'], ['p', '456']], ['p', '456']), [['p', '123']]);
-});