feat: add digest command and tests

Author: PavelPashov

packages/client/lib/commands/DIGEST.spec.ts

@@ -0,0 +1,35 @@
+import { strict as assert } from "node:assert";
+import DIGEST from "./DIGEST";
+import { parseArgs } from "./generic-transformers";
+import testUtils, { GLOBAL } from "../test-utils";
+
+describe("DIGEST", () => {
+  describe("transformArguments", () => {
+    it("digest", () => {
+      assert.deepEqual(parseArgs(DIGEST, "key"), ["DIGEST", "key"]);
+    });
+  });
+
+  testUtils.testAll(
+    "existing key",
+    async (client) => {
+      await client.set("key{tag}", "value");
+      assert.equal(typeof await client.digest("key{tag}"), "string");
+    },
+    {
+      client: { ...GLOBAL.SERVERS.OPEN, minimumDockerVersion: [8, 4] },
+      cluster: { ...GLOBAL.CLUSTERS.OPEN, minimumDockerVersion: [8, 4] },
+    }
+  );
+
+  testUtils.testAll(
+    "non-existing key",
+    async (client) => {
+      assert.equal(await client.digest("key{tag}"), null);
+    },
+    {
+      client: { ...GLOBAL.SERVERS.OPEN, minimumDockerVersion: [8, 4] },
+      cluster: { ...GLOBAL.CLUSTERS.OPEN, minimumDockerVersion: [8, 4] },
+    }
+  );
+});

packages/client/lib/commands/DIGEST.ts

@@ -0,0 +1,17 @@
+import { CommandParser } from "../client/parser";
+import { Command, RedisArgument, SimpleStringReply } from "../RESP/types";
+
+export default {
+  IS_READ_ONLY: true,
+  /**
+   * Returns the XXH3 hash of a string value.
+   *
+   * @param parser - The Redis command parser
+   * @param key - Key to get the digest of
+   */
+  parseCommand(parser: CommandParser, key: RedisArgument) {
+    parser.push("DIGEST");
+    parser.pushKey(key);
+  },
+  transformReply: undefined as unknown as () => SimpleStringReply,
+} as const satisfies Command;

packages/client/lib/commands/index.ts

@@ -84,6 +84,7 @@ import DBSIZE from './DBSIZE';
 import DECR from './DECR';
 import DECRBY from './DECRBY';
 import DEL from './DEL';
+import DIGEST from './DIGEST';
 import DUMP from './DUMP';
 import ECHO from './ECHO';
 import EVAL_RO from './EVAL_RO';
@@ -543,6 +544,8 @@ export default {
   decrBy: DECRBY,
   DEL,
   del: DEL,
+  DIGEST,
+  digest: DIGEST,
   DUMP,
   dump: DUMP,
   ECHO,