Fix a bug where the codingPath isn't correctly updated throughout nes…

…ted generic decoding steps
orlandos-nl · Jan 6, 2023 · 07e5de4 · 07e5de4
1 parent 5fb64b7
commit 07e5de4
Show file tree

Hide file tree

Showing 3 changed files with 18 additions and 8 deletions.
diff --git a/README.md b/README.md
@@ -33,7 +33,7 @@ struct User: Codable {
     let name: String
 }
 
-let data = Data()
+let data: Data = ...
 var decoder = IkigaJSONDecoder()
 let user = try decoder.decode(User.self, from: data)
 ```

diff --git a/Sources/IkigaJSON/Codable/JSONDecoder.swift b/Sources/IkigaJSON/Codable/JSONDecoder.swift
@@ -82,7 +82,7 @@ public final class IkigaJSONDecoder {
         var parser = JSONParser(pointer: pointer, count: buffer.count)
         try parser.scanValue()
 
-        let decoder = _JSONDecoder(description: parser.description, pointer: pointer, settings: settings)
+        let decoder = _JSONDecoder(description: parser.description, codingPath: [], pointer: pointer, settings: settings)
         let type = try D(from: decoder)
         return type
     }
@@ -99,6 +99,7 @@ public final class IkigaJSONDecoder {
         return try object.jsonBuffer.withUnsafeReadableBytes { buffer in
             let decoder = _JSONDecoder(
                 description: object.description,
+                codingPath: [],
                 pointer: buffer.baseAddress!.bindMemory(to: UInt8.self, capacity: buffer.count),
                 settings: settings
             )
@@ -112,6 +113,7 @@ public final class IkigaJSONDecoder {
         return try array.jsonBuffer.withUnsafeReadableBytes { buffer in
             let decoder = _JSONDecoder(
                 description: array.description,
+                codingPath: [],
                 pointer: buffer.baseAddress!.bindMemory(to: UInt8.self, capacity: buffer.count),
                 settings: settings
             )
@@ -158,7 +160,7 @@ public final class IkigaJSONDecoder {
             var parser = JSONParser(pointer: pointer, count: buffer.count)
             try parser.scanValue()
 
-            let decoder = _JSONDecoder(description: parser.description, pointer: pointer, settings: settings)
+            let decoder = _JSONDecoder(description: parser.description, codingPath: [], pointer: pointer, settings: settings)
             let type = try D(from: decoder)
             return (parser.currentOffset, type)
         }
@@ -170,7 +172,7 @@ public final class IkigaJSONDecoder {
         parser: JSONParser,
         settings: JSONDecoderSettings = JSONDecoderSettings()
     ) throws -> D {
-        let decoder = _JSONDecoder(description: parser.description, pointer: buffer.baseAddress!, settings: settings)
+        let decoder = _JSONDecoder(description: parser.description, codingPath: [], pointer: buffer.baseAddress!, settings: settings)
         return try D(from: decoder)
     }
 }
@@ -181,7 +183,7 @@ fileprivate struct _JSONDecoder: Decoder {
     let settings: JSONDecoderSettings
     var snakeCasing: Bool
 
-    var codingPath = [CodingKey]()
+    var codingPath: [CodingKey]
     var userInfo: [CodingUserInfoKey : Any] {
         return settings.userInfo
     }
@@ -215,9 +217,10 @@ fileprivate struct _JSONDecoder: Decoder {
         return SingleValueJSONDecodingContainer(decoder: self)
     }
 
-    init(description: JSONDescription, pointer: UnsafePointer<UInt8>, settings: JSONDecoderSettings) {
+    init(description: JSONDescription, codingPath: [CodingKey], pointer: UnsafePointer<UInt8>, settings: JSONDecoderSettings) {
         self.description = description
         self.pointer = pointer
+        self.codingPath = codingPath
         self.settings = settings
 
         if case .convertFromSnakeCase = settings.keyDecodingStrategy {
@@ -229,7 +232,7 @@ fileprivate struct _JSONDecoder: Decoder {
 
     func subDecoder(offsetBy offset: Int) -> _JSONDecoder {
         let subDescription = self.description.subDescription(offset: offset)
-        return _JSONDecoder(description: subDescription, pointer: pointer, settings: settings)
+        return _JSONDecoder(description: subDescription, codingPath: codingPath, pointer: pointer, settings: settings)
     }
 
     func decode<D: Decodable>(_ type: D.Type) throws -> D {
@@ -441,7 +444,9 @@ fileprivate struct KeyedJSONDecodingContainer<Key: CodingKey>: KeyedDecodingCont
         ) else {
             throw failureError
         }
-        return self.decoder.subDecoder(offsetBy: offset)
+        var subDecoder = self.decoder.subDecoder(offsetBy: offset)
+        subDecoder.codingPath.append(key)
+        return subDecoder
     }
 
     func decode<T>(_: T.Type, forKey key: Key) throws -> T where T : Decodable {

diff --git a/Sources/IkigaJSON/Codable/JSONEncoder.swift b/Sources/IkigaJSON/Codable/JSONEncoder.swift
@@ -220,6 +220,7 @@ public struct IkigaJSONEncoder {
         return data
     }
 
+    /// Encodes the provided value as JSON into the given buffer.
     public func encodeAndWrite<E: Encodable>(_ value: E, into buffer: inout ByteBuffer) throws {
         let encoder = _JSONEncoder(userInfo: userInfo, settings: settings)
         try value.encode(to: encoder)
@@ -229,6 +230,8 @@ public struct IkigaJSONEncoder {
         encoder.cleanUp()
     }
 
+    /// Encodes the provided value as JSON and returns a JSON Object.
+    /// If the value is not a JSON Object, an error is thrown.
     public func encodeJSONObject<E: Encodable>(from value: E) throws -> JSONObject {
         let encoder = _JSONEncoder(userInfo: userInfo, settings: settings)
         try value.encode(to: encoder)
@@ -239,6 +242,8 @@ public struct IkigaJSONEncoder {
         return object
     }
 
+    /// Encodes the provided value as JSON and returns a JSON Array.
+    /// If the value is not a JSON Array, an error is thrown.
     public func encodeJSONArray<E: Encodable>(from value: E) throws -> JSONArray {
         let encoder = _JSONEncoder(userInfo: userInfo, settings: settings)
         try value.encode(to: encoder)