feat: auto flexible type with trait (#35)

* feat: auto flexible type by trait

* Update documents

Author: vnixx

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version: 6.0
+// swift-tools-version: 6.1
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
@@ -15,31 +15,29 @@ let package = Package(
         .visionOS(.v1)
     ],
     products: [
-        // Products define the executables and libraries a package produces, making them visible to other packages.
         .library(
             name: "ReerCodable",
             targets: ["ReerCodable"]
         )
     ],
+    traits: [
+        .trait(
+            name: "AutoFlexibleType",
+            description: "Enable automatic type conversion for all @Codable/@Decodable types"
+        ),
+    ],
     dependencies: [
         .package(url: "https://github.com/swiftlang/swift-syntax", from: "600.0.0"),
     ],
     targets: [
-        // Targets are the basic building blocks of a package, defining a module or a test suite.
-        // Targets can depend on other targets in this package and products from dependencies.
-        // Macro implementation that performs the source transformation of a macro.
         .macro(
             name: "ReerCodableMacros",
             dependencies: [
                 .product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
                 .product(name: "SwiftCompilerPlugin", package: "swift-syntax")
             ]
         ),
-
-        // Library that exposes a macro as part of its API, which is used in client programs.
         .target(name: "ReerCodable", dependencies: ["ReerCodableMacros"]),
-
-        // A test target used to develop the macro implementation.
         .testTarget(
             name: "ReerCodableTests",
             dependencies: [

README.md

@@ -729,6 +729,25 @@ struct Settings {
 }
 ```
 
+#### AutoFlexibleType Trait (Swift 6.1+)
+
+If you prefer all types automatically support flexible type conversion without explicit `@FlexibleType` annotation, you can enable the `AutoFlexibleType` trait when adding the package dependency:
+
+```swift
+// In your Package.swift
+.package(
+    url: "https://github.com/reers/ReerCodable.git",
+    from: "1.6.0",
+    traits: ["AutoFlexibleType"]
+)
+```
+
+When this trait is enabled, all `@Codable` and `@Decodable` types will automatically support flexible type conversion, just like having `@FlexibleType` applied to every type. This is useful for projects that rely on backend APIs with inconsistent data types.
+
+> **Note:** This feature requires Swift 6.1+ and swift-tools-version: 6.1 in your Package.swift.
+
+> **Important:** After changing traits, you must **delete DerivedData/YourProject** and **restart Xcode** for the changes to take effect.
+
 ### 18. AnyCodable Support
 
 Implement encoding/decoding of `Any` type through `AnyCodable`:

README_CN.md

@@ -724,6 +724,25 @@ struct Settings {
 }
 ```
 
+#### AutoFlexibleType Trait (Swift 6.1+)
+
+如果你希望所有类型自动支持灵活类型转换而无需显式标注 `@FlexibleType`，可以在添加包依赖时启用 `AutoFlexibleType` trait：
+
+```swift
+// 在你的 Package.swift 中
+.package(
+    url: "https://github.com/reers/ReerCodable.git",
+    from: "1.6.0",
+    traits: ["AutoFlexibleType"]
+)
+```
+
+启用此 trait 后，所有 `@Codable` 和 `@Decodable` 类型将自动支持灵活类型转换，就像每个类型都应用了 `@FlexibleType` 一样。这对于依赖后端 API 数据类型不一致的项目非常有用。
+
+> **注意：** 此功能需要 Swift 6.1+ 并且你的 Package.swift 中需要设置 swift-tools-version: 6.1。
+
+> **重要：** 修改 traits 后，必须**删除 DerivedData/YourProject** 并**重启 Xcode** 才能使更改生效。
+
 ### 18. AnyCodable 支持
 
 通过 `AnyCodable` 实现对 `Any` 类型的编解码：

Sources/ReerCodable/MacroDeclarations/FlexibleType.swift

@@ -48,5 +48,20 @@
 /// ```
 ///
 /// The supported type conversions are defined in the `TypeConvertible` protocol implementations.
+///
+/// ## AutoFlexibleType Trait (Swift 6.1+)
+///
+/// If you prefer automatic type conversion for all types without explicit annotation,
+/// you can enable the `AutoFlexibleType` trait when adding the package dependency:
+///
+/// ```swift
+/// .package(
+///     url: "https://github.com/reers/ReerCodable.git",
+///     from: "1.6.0",
+///     traits: ["AutoFlexibleType"]
+/// )
+/// ```
+///
+/// - Important: After changing traits, you must delete DerivedData/YourProject and restart Xcode for the changes to take effect.
 @attached(peer)
 public macro FlexibleType() = #externalMacro(module: "ReerCodableMacros", type: "FlexibleType")

Sources/ReerCodableMacros/TypeInfo.swift

@@ -246,6 +246,10 @@ struct TypeInfo {
         if decl.attributes.containsAttribute(named: "FlexibleType") {
             isFlexibleType = true
         }
+        #if AutoFlexibleType
+        // When AutoFlexibleType trait is enabled, all types default to flexible type conversion
+        isFlexibleType = true
+        #endif
         // Check if the class inherits from NSObject
         if let classDecl = decl.as(ClassDeclSyntax.self),
            let inheritedTypes = classDecl.inheritanceClause?.inheritedTypes {