fix: improve signature of spop (#31)

* fix: improve signature of spop

* fix: add tests for spop

redis.ts

@@ -232,7 +232,8 @@ export type Redis = {
   sismember(key: string, member: string): Promise<number>;
   smembers(key: string): Promise<string[]>;
   smove(source: string, destination: string, member: string): Promise<number>;
-  spop(key: string, count?: number): Promise<string>;
+  spop(key: string): Promise<string>;
+  spop(key: string, count: number): Promise<string[]>;
   srandmember(key: string, count?: number): Promise<string>;
   srem(key: string, ...members: string[]): Promise<number>;
   sunion(...keys: string[]): Promise<string[]>;
@@ -1266,7 +1267,9 @@ class RedisImpl implements Redis {
     }
   }
 
-  spop(...args) {
+  spop(key: string): Promise<string>;
+  spop(key: string, count: number): Promise<string[]>;
+  spop(...args): Promise<string | string[]> {
     return this.execStatusReply("SPOP", ...args);
   }
 

redis_test.ts

@@ -6,7 +6,8 @@ import {
 } from "./vendor/https/deno.land/std/testing/mod.ts";
 import {
   assertEquals,
-  assertThrowsAsync
+  assertThrowsAsync,
+  assertArrayContains
 } from "./vendor/https/deno.land/std/testing/asserts.ts";
 // can be substituted with env variable
 const addr = {
@@ -25,7 +26,9 @@ test(async function beforeAll() {
     "get",
     "getset",
     "del1",
-    "del2"
+    "del2",
+    "spop",
+    "spopWithCount"
   );
 });
 
@@ -97,6 +100,18 @@ test(async function testDecrby() {
   assertEquals(await redis.get("decryby"), "-101");
 });
 
+test(async function testSpop() {
+  await redis.sadd("spop", "a");
+  const v = await redis.spop("spop");
+  assertEquals(v, "a");
+});
+
+test(async function testSpopWithCount() {
+  await redis.sadd("spopWithCount", "a", "b");
+  const v = await redis.spop("spopWithCount", 2);
+  assertArrayContains(v, ["a", "b"]);
+});
+
 test(async function testConcurrent() {
   let promises: Promise<any>[] = [];
   for (const key of ["a", "b", "c"]) {