handle lpop and rpop with a count higher than 1

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## 4.0.0 - 2025-08-15
+
+- Update `lpop` and `rpop` to return string arrays. Previously they would error if a
+  count higher than 1 was provided.
+
 ## 3.0.0 - 2025-06-29
 
 - Update `mug` and add support for IPv6 connections.

gleam.toml

@@ -1,5 +1,5 @@
 name = "valkyrie"
-version = "3.0.0"
+version = "4.0.0"
 
 description = "A Gleam client for Valkey, KeyDB, Redis, Dragonfly and other Redis-compatible databases."
 gleam = ">= 1.11.0"

src/valkyrie.gleam

@@ -711,6 +711,7 @@ fn expect_bulk_string_array(
             )
         }
       })
+    [resp.Null] -> Error(NotFound)
     _ -> Error(RespError(resp.error_string(expected: "array", got: value)))
   }
 }
@@ -1593,21 +1594,10 @@ pub fn lpop(
   key: String,
   count: Int,
   timeout: Int,
-) -> Result(String, Error) {
+) -> Result(List(String), Error) {
   ["LPOP", key, int.to_string(count)]
   |> execute(conn, _, timeout)
-  |> result.try(fn(value) {
-    case value {
-      // When count is provided, Redis returns an array
-      [resp.Array([resp.BulkString(str)])] -> Ok(str)
-      [resp.Array([])] -> Error(NotFound)
-      [resp.Null] -> Error(NotFound)
-      _ ->
-        Error(
-          RespError(resp.error_string(expected: "string or array", got: value)),
-        )
-    }
-  })
+  |> result.try(expect_bulk_string_array)
 }
 
 /// Remove and return elements from the right (tail) of a list.
@@ -1620,21 +1610,10 @@ pub fn rpop(
   key: String,
   count: Int,
   timeout: Int,
-) -> Result(String, Error) {
+) -> Result(List(String), Error) {
   ["RPOP", key, int.to_string(count)]
   |> execute(conn, _, timeout)
-  |> result.try(fn(value) {
-    case value {
-      // When count is provided, Redis returns an array
-      [resp.Array([resp.BulkString(str)])] -> Ok(str)
-      [resp.Array([])] -> Error(NotFound)
-      [resp.Null] -> Error(NotFound)
-      _ ->
-        Error(
-          RespError(resp.error_string(expected: "string or array", got: value)),
-        )
-    }
-  })
+  |> result.try(expect_bulk_string_array)
 }
 
 /// Get an element from a list by its index.

test/valkyrie_test.gleam

@@ -822,11 +822,38 @@ pub fn lpop_rpop_test() {
 
   let assert Ok(_) = valkyrie.rpush(conn, "test:pop", ["a", "b", "c"], 1000)
 
-  let assert Ok("a") = valkyrie.lpop(conn, "test:pop", 1, 1000)
-  let assert Ok("c") = valkyrie.rpop(conn, "test:pop", 1, 1000)
+  let assert Ok(["a"]) = valkyrie.lpop(conn, "test:pop", 1, 1000)
+  let assert Ok(["c"]) = valkyrie.rpop(conn, "test:pop", 1, 1000)
   let assert Ok(1) = valkyrie.llen(conn, "test:pop", 1000)
 }
 
+pub fn lpop_rpop_multiple_test() {
+  use conn <- get_test_conn()
+
+  let assert Ok(_) =
+    valkyrie.rpush(conn, "test:pop_multiple", ["a", "b", "c", "d", "e"], 1000)
+
+  // Pop multiple from left
+  let assert Ok(["a", "b"]) = valkyrie.lpop(conn, "test:pop_multiple", 2, 1000)
+  let assert Ok(3) = valkyrie.llen(conn, "test:pop_multiple", 1000)
+
+  // Pop multiple from right
+  let assert Ok(["e", "d"]) = valkyrie.rpop(conn, "test:pop_multiple", 2, 1000)
+  let assert Ok(1) = valkyrie.llen(conn, "test:pop_multiple", 1000)
+
+  let assert Ok(["c"]) = valkyrie.lpop(conn, "test:pop_multiple", 3, 1000)
+  let assert Ok(0) = valkyrie.llen(conn, "test:pop_multiple", 1000)
+
+  let assert Error(valkyrie.NotFound) =
+    valkyrie.lpop(conn, "test:pop_multiple", 1, 1000)
+  let assert Error(valkyrie.NotFound) =
+    valkyrie.lpop(conn, "test:pop_multiple", 2, 1000)
+  let assert Error(valkyrie.NotFound) =
+    valkyrie.rpop(conn, "test:pop_multiple", 1, 1000)
+  let assert Error(valkyrie.NotFound) =
+    valkyrie.rpop(conn, "test:pop_multiple", 2, 1000)
+}
+
 pub fn lindex_test() {
   use conn <- get_test_conn()