From c4509f0bc5ea8ba46e6f3d1315c79c95438e5f0c Mon Sep 17 00:00:00 2001
From: Brad Dunbar <dunbarb2@gmail.com>
Date: Mon, 31 Aug 2020 11:15:02 -0400
Subject: [PATCH] Add STRALGO command (#141)

---
 command.ts           | 12 ++++++++++++
 redis.ts             | 29 +++++++++++++++++++++++++++++
 tests/string_test.ts | 38 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+)

diff --git a/command.ts b/command.ts
index 18a8fa84..8d095e85 100644
--- a/command.ts
+++ b/command.ts
@@ -184,6 +184,18 @@ export type RedisCommands = {
   setex(key: string, seconds: number, value: string): Promise<Status>;
   setnx(key: string, value: string): Promise<Integer>;
   setrange(key: string, offset: number, value: string): Promise<Integer>;
+  stralgo(
+    algorithm: "LCS",
+    target: "KEYS" | "STRINGS",
+    a: string,
+    b: string,
+    opts?: {
+      idx?: boolean;
+      len?: boolean;
+      minmatchlen?: number;
+      withmatchlen?: boolean;
+    },
+  ): Promise<Bulk>;
   strlen(key: string): Promise<Integer>;
 
   // Geo
diff --git a/redis.ts b/redis.ts
index b98914f1..395a32f4 100644
--- a/redis.ts
+++ b/redis.ts
@@ -1289,6 +1289,35 @@ export class RedisImpl implements Redis {
     return this.execIntegerReply("SREM", key, ...members);
   }
 
+  stralgo(
+    algorithm: "LCS",
+    target: "KEYS" | "STRINGS",
+    a: string,
+    b: string,
+    opts?: {
+      idx?: boolean;
+      len?: boolean;
+      minmatchlen?: number;
+      withmatchlen?: boolean;
+    },
+  ) {
+    const args: (number | string)[] = [];
+    if (opts?.idx) {
+      args.push("IDX");
+    }
+    if (opts?.len) {
+      args.push("LEN");
+    }
+    if (opts?.withmatchlen) {
+      args.push("WITHMATCHLEN");
+    }
+    if (opts?.minmatchlen) {
+      args.push("MINMATCHLEN");
+      args.push(opts.minmatchlen);
+    }
+    return this.execBulkReply("STRALGO", "LCS", target, a, b, ...args);
+  }
+
   strlen(key: string) {
     return this.execIntegerReply("STRLEN", key);
   }
diff --git a/tests/string_test.ts b/tests/string_test.ts
index c76492de..7ed2d643 100644
--- a/tests/string_test.ts
+++ b/tests/string_test.ts
@@ -202,6 +202,44 @@ suite.test("setrange", async () => {
   assertEquals(v, "Hello, Redis!");
 });
 
+suite.test("stralgo", async () => {
+  await client.set("a", "Hello");
+  await client.set("b", "Deno!");
+  const matches = [[[4, 4], [3, 3]], [[1, 1], [1, 1]]];
+  const matchesWithLen = [[[4, 4], [3, 3], 1], [[1, 1], [1, 1], 1]];
+  assertEquals(await client.stralgo("LCS", "KEYS", "a", "b"), "eo");
+  assertEquals(await client.stralgo("LCS", "KEYS", "a", "b", { len: true }), 2);
+  assertEquals(
+    await client.stralgo("LCS", "KEYS", "a", "b", { idx: true }),
+    ["matches", matches, "len", 2],
+  );
+  assertEquals(
+    await client.stralgo(
+      "LCS",
+      "KEYS",
+      "a",
+      "b",
+      { idx: true, withmatchlen: true },
+    ),
+    ["matches", matchesWithLen, "len", 2],
+  );
+  assertEquals(
+    await client.stralgo(
+      "LCS",
+      "KEYS",
+      "a",
+      "b",
+      { idx: true, minmatchlen: 2 },
+    ),
+    ["matches", [], "len", 2],
+  );
+  assertEquals(await client.stralgo("LCS", "STRINGS", "Hello", "Deno!"), "eo");
+  assertEquals(
+    await client.stralgo("LCS", "STRINGS", "Hello", "Deno!", { len: true }),
+    2,
+  );
+});
+
 suite.test("strlen", async () => {
   await client.set("key", "foobar");
   const v = await client.strlen("key");