Helper decode functions

Signed-off-by: Adam Fowler <adamfowler71@gmail.com>

Author: adam-fowler

Sources/Valkey/RESP/RESPToken.swift

@@ -37,6 +37,7 @@ public struct RESPToken: Hashable, Sendable {
             }
         }
 
+        @usableFromInline
         internal func asMap() throws -> Map {
             guard (self.count & 1) == 0 else { throw RESPParsingError(code: .invalidElementCount, buffer: self.buffer) }
             return Map(count: self.count / 2, buffer: self.buffer)

Sources/Valkey/RESP/RESPTokenDecodable.swift

@@ -298,13 +298,7 @@ extension Dictionary: RESPTokenDecodable where Value: RESPTokenDecodable, Key: R
     public init(fromRESP token: RESPToken) throws {
         switch token.value {
         case .map(let respMap), .attribute(let respMap):
-            var array: [(Key, Value)] = []
-            for respElement in respMap {
-                let key = try Key(fromRESP: respElement.key)
-                let value = try Value(fromRESP: respElement.value)
-                array.append((key, value))
-            }
-            self = .init(array) { first, _ in first }
+            self = try respMap.decode(as: Self.self)
         default:
             throw RESPDecodeError.tokenMismatch(expected: [.map], token: token)
         }
@@ -358,7 +352,7 @@ extension RESPToken.Array: RESPTokenDecodable {
         return try (repeat decodeOptionalRESPToken(iterator.next(), as: (each Value).self))
     }
 
-    /// Convert RESP3Token Array to a tuple of values
+    /// Convert RESPToken Array to a tuple of values
     /// - Parameter type: Tuple of types to convert to
     /// - Throws: RESPDecodeError
     /// - Returns: Tuple of decoded values
@@ -378,6 +372,16 @@ extension RESPToken.Array: RESPTokenDecodable {
         return (repeat decodeOptionalRESPToken(iterator.next(), as: (each Value).self))
     }
 
+    /// Decode RESPToken Array consisting of alternating key, value entries
+    /// - Parameter as: Array of key value pairs type
+    /// - Returns: Array of key value pairs
+    @inlinable
+    public func decodeKeyValuePairs<Key: RESPTokenDecodable, Value: RESPTokenDecodable>(
+        as: [(Key, Value)].Type = [(Key, Value)].self
+    ) throws -> [(Key, Value)] {
+        try self.asMap().decode()
+    }
+
     @inlinable
     func _parameterPackTypeSize<each Value>(
         _ type: (repeat (each Value)).Type
@@ -402,18 +406,28 @@ extension RESPToken.Map: RESPTokenDecodable {
         }
     }
 
-    /// Convert RESPToken Map to a Dictionary with String keys
+    /// Convert RESPToken Map to a Dictionary
     /// - Parameter type: Type to convert to
     /// - Throws: ValkeyClientError.unexpectedType
     /// - Returns: String value dictionary
     @inlinable
-    public func decode<Value: RESPTokenDecodable>(as type: [String: Value].Type = [String: Value].self) throws -> [String: Value] {
-        var array: [(String, Value)] = []
-        for respElement in self {
-            let key = try String(fromRESP: respElement.key)
-            let value = try Value(fromRESP: respElement.value)
-            array.append((key, value))
-        }
+    public func decode<Key: RESPTokenDecodable & Hashable, Value: RESPTokenDecodable>(
+        as type: [Key: Value].Type = [Key: Value].self
+    ) throws -> [Key: Value] {
+        let array = try self.decode(as: [(Key, Value)].self)
         return .init(array) { first, _ in first }
     }
+
+    /// Convert RESPToken Map to a Array of Key Value pairs
+    /// - Parameter type: Type to convert to
+    /// - Throws: ValkeyClientError.unexpectedType
+    /// - Returns: String value dictionary
+    @inlinable
+    public func decode<Key: RESPTokenDecodable, Value: RESPTokenDecodable>(
+        as type: [(Key, Value)].Type = [(Key, Value)].self
+    ) throws -> [(Key, Value)] {
+        try self.map {
+            try (Key(fromRESP: $0.key), Value(fromRESP: $0.value))
+        }
+    }
 }

Tests/ValkeyTests/RESPTokenRepresentableTests.swift renamed to Tests/ValkeyTests/RESPTokenDecodableTests.swift

@@ -9,7 +9,7 @@ import NIOCore
 import Testing
 import Valkey
 
-struct RESPTokenRepresentableTests {
+struct RESPTokenDecodableTests {
     @Test(arguments: [
         ("+SimpleString\r\n", "SimpleString"),
         ("$10\r\nBulkString\r\n", "BulkString"),
@@ -124,10 +124,29 @@ struct RESPTokenRepresentableTests {
         ("*2\r\n:1\r\n:45\r\n", [1...45]),
         ("*2\r\n*2\r\n:1\r\n:6\r\n*2\r\n:8\r\n:34\r\n", [1...6, 8...34]),
     ])
-    func arrayOfArrays(testValues: (String, [ClosedRange<Int>])) throws {
+    func arrayOfRanges(testValues: (String, [ClosedRange<Int>])) throws {
         var buffer = ByteBuffer(string: testValues.0)
         let token = try #require(try RESPToken(consuming: &buffer))
         let value = try [ClosedRange<Int>](fromRESP: token)
         #expect(value == testValues.1)
     }
+
+    @Test(arguments: [
+        ("*2\r\n$3\r\none\r\n$1\r\n1\r\n", [("one", "1")]),
+        ("*4\r\n$3\r\none\r\n$1\r\n1\r\n$3\r\ntwo\r\n$1\r\n2\r\n", [("one", "1"), ("two", "2")]),
+    ])
+    func arrayOfKeyValuePairs(testValues: (String, [(String, String)])) throws {
+        var buffer = ByteBuffer(string: testValues.0)
+        let token = try #require(try RESPToken(consuming: &buffer))
+        switch token.value {
+        case .array(let array):
+            let values = try array.decodeKeyValuePairs(as: [(String, String)].self)
+            #expect(values.count == testValues.1.count)
+            for i in 0..<values.count {
+                #expect(values[i] == testValues.1[i])
+            }
+        default:
+            Issue.record("Token is not an array")
+        }
+    }
 }