Fix encoding top-level TLVCodable values

Author: colemancda

Sources/Decoder.swift

@@ -38,21 +38,27 @@ public struct TLVDecoder {
 
         log?("Will decode \(String(reflecting: T.self))")
 
-        let items = try decode(data)
-        
-        let options = Decoder.Options(
-            numericFormatting: numericFormatting,
-            uuidFormatting: uuidFormatting,
-            dateFormatting: dateFormatting
-        )
-        
-        let decoder = Decoder(referencing: .items(items),
-                              userInfo: userInfo,
-                              log: log,
-                              options: options)
-        
-        // decode from container
-        return try T.init(from: decoder)
+        if let tlvCodable = type as? TLVDecodable.Type {
+            guard let value = tlvCodable.init(tlvData: data) else {
+                throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: [], debugDescription: "Invalid data for \(String(reflecting: type))"))
+            }
+            return value as! T
+        } else {
+            let items = try decode(data)
+            let options = Decoder.Options(
+                numericFormatting: numericFormatting,
+                uuidFormatting: uuidFormatting,
+                dateFormatting: dateFormatting
+            )
+            let decoder = Decoder(
+                referencing: .items(items),
+                userInfo: userInfo,
+                log: log,
+                options: options
+            )
+            // decode from container
+            return try T.init(from: decoder)
+        }
     }
 
     public func decode(_ data: Data) throws -> [TLVItem] {
@@ -311,7 +317,7 @@ internal extension TLVDecoder.Decoder {
             return try unboxUUID(item.value) as! T
         } else if type == Date.self {
             return try unboxDate(item.value) as! T
-        } else if let tlvCodable = type as? TLVCodable.Type {
+        } else if let tlvCodable = type as? TLVDecodable.Type {
             guard let value = tlvCodable.init(tlvData: item.value) else {
                 throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: codingPath, debugDescription: "Invalid data for \(String(reflecting: type))"))
             }

Sources/Encoder.swift

@@ -41,22 +41,23 @@ public struct TLVEncoder {
 
         log?("Will encode \(String(reflecting: T.self))")
 
-        let options = Encoder.Options(
-            outputFormatting: outputFormatting,
-            numericFormatting: numericFormatting,
-            uuidFormatting: uuidFormatting,
-            dateFormatting: dateFormatting
-        )
-        
-        let encoder = Encoder(userInfo: userInfo, log: log, options: options)
-        try value.encode(to: encoder)
-        assert(encoder.stack.containers.count == 1)
-        
-        guard case let .items(container) = encoder.stack.root else {
-            throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) is not encoded as items."))
+        if let encodable = value as? TLVEncodable {
+            return encodable.tlvData
+        } else {
+            let options = Encoder.Options(
+                outputFormatting: outputFormatting,
+                numericFormatting: numericFormatting,
+                uuidFormatting: uuidFormatting,
+                dateFormatting: dateFormatting
+            )
+            let encoder = Encoder(userInfo: userInfo, log: log, options: options)
+            try value.encode(to: encoder)
+            assert(encoder.stack.containers.count == 1)
+            guard case let .items(container) = encoder.stack.root else {
+                throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: [], debugDescription: "Top-level \(T.self) is not encoded as items."))
+            }
+            return container.data
         }
-        
-        return container.data
     }
 
     public func encode(_ items: [TLVItem]) -> Data {

Tests/TLVCodingTests/TLVCodingTests.swift

@@ -74,6 +74,11 @@ final class TLVCodingTests: XCTestCase {
             uint64: 30_000),
              Data([0, 1, 1, 1, 4, 246, 255, 255, 255, 2, 4, 10, 0, 0, 0, 3, 4, 146, 203, 143, 63, 4, 8, 114, 138, 142, 228, 242, 255, 37, 64, 5, 1, 127, 6, 2, 56, 255, 7, 4, 48, 248, 255, 255, 8, 8, 224, 177, 255, 255, 255, 255, 255, 255, 9, 1, 255, 10, 2, 44, 1, 11, 4, 184, 11, 0, 0, 12, 8, 48, 117, 0, 0, 0, 0, 0, 0]))
 
+        compare(
+            Version(major: 1, minor: 2, patch: 3),
+            Data([0x01, 0x02, 0x03])
+        )
+        
         compare(
             CustomEncodable(
                 data: nil,
@@ -371,9 +376,7 @@ final class TLVCodingTests: XCTestCase {
         )
 
         XCTAssertEqual(try encoder.encode(value), try encoder.encode(valueUnordered))
-        
         encoder.outputFormatting.sortedKeys = false
-        
         XCTAssertNotEqual(try encoder.encode(value), try encoder.encode(valueUnordered))
     }
 }