add some missing commands

lib/commands/GETBIT.spec.ts

@@ -0,0 +1,26 @@
+import { strict as assert } from 'assert';
+import { TestRedisServers, itWithClient, TestRedisClusters, itWithCluster } from '../test-utils';
+import { transformArguments } from './GETBIT';
+
+describe('GETBIT', () => {
+    it('transformArguments', () => {
+        assert.deepEqual(
+            transformArguments('key', 0),
+            ['GETBIT', 'key', '0']
+        );
+    });
+
+    itWithClient(TestRedisServers.OPEN, 'client.getBit', async client => {
+        assert.equal(
+            await client.getBit('key', 0),
+            0
+        );
+    });
+
+    itWithCluster(TestRedisClusters.OPEN, 'cluster.getBit', async cluster => {
+        assert.equal(
+            await cluster.getBit('key', 0),
+            0
+        );
+    });
+});