优化key的自定义映射规则

Author: Mccc

Example/Podfile.lock

@@ -8,7 +8,7 @@ PODS:
   - FBSnapshotTestCase/SwiftSupport (2.1.4):
     - FBSnapshotTestCase/Core
   - HandyJSON (5.0.0-beta.1)
-  - SmartCodable (4.2.3)
+  - SmartCodable (4.2.5)
   - SnapKit (5.6.0)
 
 DEPENDENCIES:
@@ -39,7 +39,7 @@ SPEC CHECKSUMS:
   CleanJSON: 910a36465ce4829e264a902ccf6d1455fdd9f980
   FBSnapshotTestCase: 094f9f314decbabe373b87cc339bea235a63e07a
   HandyJSON: 582477127ab3ab65bd2e471815f1a7b846856978
-  SmartCodable: f01c43e62a8867828fb9f51f4b354b657dafc37d
+  SmartCodable: b39182ec8f12298f277a1c0ec7a7c1031bbfce1b
   SnapKit: e01d52ebb8ddbc333eefe2132acf85c8227d9c25
 
 PODFILE CHECKSUM: 7f3af03f81934df0c035518074a7abbec8fa9d3f

Example/Pods/Local Podspecs/SmartCodable.podspec.json

@@ -16,39 +16,29 @@ class Test2ViewController: BaseViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
 
+        SmartConfig.debugMode = .none
+        
         let dict: [String: Any] = [
-//            "name": "mccc",
             "age": 30,
+            "name": "Mccc",
+            "newName": "newMccc",
             "info": [
                 "name": "mccc111"
             ],
-            "sub": [
-                "subname": "qilin",
-                "subage": 3,
-                "info": [
-                    "name": "qilin111"
-                ],
-            ]
-
         ]
         let model = Model.deserialize(from: dict)
         BTPrint.print(model)
-
-        print("\n")
-        
-        let tranDict = model?.toDictionary() ?? [:]
-        BTPrint.print(tranDict)
     }
 }
 
 struct Model: SmartCodable {
     var name: String = ""
     var age: Int = 0
-    var sub: SubModel = SubModel()
+    
 
     static func mappingForKey() -> [SmartKeyTransformer]? {
         [
-            CodingKeys.name <--- "info.name"
+            CodingKeys.name <--- ["info.name", "newName", "name", ]
         ]
     }
 }

Example/Pods/Manifest.lock

@@ -12,7 +12,7 @@
 
 Pod::Spec.new do |s|
   s.name             = 'SmartCodable'
-  s.version          = '4.2.4'
+  s.version          = '4.2.5'
   s.summary          = '数据解析库'
 
   s.homepage         = 'https://github.com/intsig171'

Example/Pods/Target Support Files/SmartCodable/SmartCodable-Info.plist

@@ -28,7 +28,7 @@ struct KeysMapper {
         }
         return nil
     }
-
+    
 
     private static func parseJSON(from string: String, as type: SmartDecodable.Type) -> Any {
         guard let jsonObject = string.toJSONObject() else { return string }
@@ -42,19 +42,24 @@ struct KeysMapper {
     private static func mapDictionary(dict: [String: Any], using type: SmartDecodable.Type) -> [String: Any] {
         var newDict = dict
         type.mappingForKey()?.forEach { mapping in
-            for oldKey in mapping.from {
-                let newKey = mapping.to.stringValue
-
-                // 先移除数据中原本的字段
+            let newKey = mapping.to.stringValue
+            
+            /** 判断原字段是否为干扰字段（映射关系中是否存在该字段）。
+             * 干扰字段场景：注意这种情况 CodingKeys.name <--- ["newName"]
+             * 有效字段场景：注意这种情况 CodingKeys.name <--- ["name", "newName"]
+             */
+            if !(mapping.from.contains(newKey)) {
                 newDict.removeValue(forKey: newKey)
-                
-                if let value = newDict[oldKey] as? JSONValue, value != .null {
+            }
+            
+            // break的作用： 优先使用第一个不为null的字段。
+            for oldKey in mapping.from {
+                if let value = newDict[oldKey] as? JSONValue, value != .null { // 映射关系在当前层
                     newDict[newKey] = newDict[oldKey]
                     break
-                } else { // Handles the case of a custom parsing path.
-                    if let pathValue = newDict.getValue(forKeyPath: oldKey) {
-                        newDict.updateValue(pathValue, forKey: newKey)
-                    }
+                } else if let pathValue = newDict.getValue(forKeyPath: oldKey) { // 映射关系需要根据路径跨层处理
+                    newDict.updateValue(pathValue, forKey: newKey)
+                    break
                 }
             }
         }

Example/SmartCodable/Test2ViewController.swift

@@ -12,7 +12,8 @@ public protocol SmartDecodable: Decodable {
     /// The callback for when mapping is complete
     mutating func didFinishMapping()
 
-    /// The mapping relationship of decoding keys
+    /// The mapping relationship of decoding keys.
+    /// The first mapping relationship that is not null is preferred
     static func mappingForKey() -> [SmartKeyTransformer]?
 
     /// The strategy for decoding values