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diff --git a/spec/frontend/lib/apollo/indexed_db_persistent_storage_spec.js b/spec/frontend/lib/apollo/indexed_db_persistent_storage_spec.js
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+import { IndexedDBPersistentStorage } from '~/lib/apollo/indexed_db_persistent_storage';
+import { db } from '~/lib/apollo/local_db';
+import CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS from './mock_data/cache_with_persist_directive_and_field.json';
+
+describe('IndexedDBPersistentStorage', () => {
+  let subject;
+
+  const seedData = async (cacheKey, data = CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS) => {
+    const { ROOT_QUERY, ...rest } = data;
+
+    await db.table('queries').put(ROOT_QUERY, cacheKey);
+
+    const asyncPuts = Object.entries(rest).map(async ([key, value]) => {
+      const {
+        groups: { type, gid },
+      } = /^(?<type>.+?):(?<gid>.+)$/.exec(key);
+      const tableName = type.toLowerCase();
+
+      if (tableName !== 'projectmember' && tableName !== 'groupmember') {
+        await db.table(tableName).put(value, gid);
+      }
+    });
+
+    await Promise.all(asyncPuts);
+  };
+
+  beforeEach(async () => {
+    subject = await IndexedDBPersistentStorage.create();
+  });
+
+  afterEach(() => {
+    db.close();
+  });
+
+  it('returns empty response if there is nothing stored in the DB', async () => {
+    const result = await subject.getItem('some-query');
+
+    expect(result).toEqual({});
+  });
+
+  it('returns stored cache if cache was persisted in IndexedDB', async () => {
+    await seedData('issues_list', CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS);
+
+    const result = await subject.getItem('issues_list');
+    expect(result).toEqual(CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS);
+  });
+
+  it('puts the results in database on `setItem` call', async () => {
+    await subject.setItem(
+      'issues_list',
+      JSON.stringify({
+        ROOT_QUERY: 'ROOT_QUERY_KEY',
+        'Project:gid://gitlab/Project/6': {
+          __typename: 'Project',
+          id: 'gid://gitlab/Project/6',
+        },
+      }),
+    );
+
+    await expect(db.table('queries').get('issues_list')).resolves.toEqual('ROOT_QUERY_KEY');
+    await expect(db.table('project').get('gid://gitlab/Project/6')).resolves.toEqual({
+      __typename: 'Project',
+      id: 'gid://gitlab/Project/6',
+    });
+  });
+
+  it('does not put results into non-existent table', async () => {
+    const queryId = 'issues_list';
+
+    await subject.setItem(
+      queryId,
+      JSON.stringify({
+        ROOT_QUERY: 'ROOT_QUERY_KEY',
+        'DNE:gid://gitlab/DNE/1': {},
+      }),
+    );
+
+    expect(db.tables.map((x) => x.name)).not.toContain('dne');
+  });
+
+  it('when removeItem is called, clears all data', async () => {
+    await seedData('issues_list', CACHE_WITH_PERSIST_DIRECTIVE_AND_FIELDS);
+
+    await subject.removeItem();
+
+    const actual = await Promise.all(db.tables.map((x) => x.toArray()));
+
+    expect(actual).toEqual(db.tables.map(() => []));
+  });
+});