Support open accesslevel

Author: ThomasDutartre

Sources/Spyable/Spyable.swift

@@ -137,7 +137,7 @@
 public macro Spyable(
   behindPreprocessorFlag: String? = nil,
   accessLevel: SpyAccessLevel? = nil,
-  inheritedTypes: String? = nil
+  inheritedType: String? = nil
 ) =
   #externalMacro(
     module: "SpyableMacro",

Sources/SpyableMacro/Extractors/Extractor.swift

@@ -106,6 +106,9 @@ struct Extractor {
     let accessLevelText = memberAccess.declName.baseName.text
 
     switch accessLevelText {
+    case "open":
+      return DeclModifierSyntax(name: .keyword(.open))
+
     case "public":
       return DeclModifierSyntax(name: .keyword(.public))
 
@@ -146,7 +149,7 @@ struct Extractor {
     protocolDeclSyntax.modifiers.first(where: \.name.isAccessLevelSupportedInProtocol)
   }
 
-  func extractInheritedTypes(
+  func extractInheritedType(
     from attribute: AttributeSyntax,
     in context: some MacroExpansionContext
   ) -> String? {
@@ -155,29 +158,30 @@ struct Extractor {
       return nil
     }
 
-    let inheritedTypesArgument = argumentList.first { argument in
-      argument.label?.text == "inheritedTypes"
+    let inheritedTypeArgument = argumentList.first { argument in
+      argument.label?.text == "inheritedType"
     }
 
-    guard let inheritedTypesArgument else {
-      // The `inheritedTypes` argument is missing.
+    guard let inheritedTypeArgument else {
+      // The `inheritedType` argument is missing.
       return nil
     }
 
-    let segments = inheritedTypesArgument.expression
+    // Check if it's a string literal expression
+    let segments = inheritedTypeArgument.expression
        .as(StringLiteralExprSyntax.self)?
        .segments
 
      guard let segments,
        segments.count == 1,
        case let .stringSegment(literalSegment)? = segments.first
      else {
-       // The `inheritedTypes` argument's value is not a static string literal.
+       // The `inheritedType` argument's value is not a valid string literal.
        context.diagnose(
          Diagnostic(
            node: attribute,
            message: SpyableDiagnostic.behindPreprocessorFlagArgumentRequiresStaticStringLiteral,
-           highlights: [Syntax(inheritedTypesArgument.expression)]
+           highlights: [Syntax(inheritedTypeArgument.expression)]
          )
        )
        return nil

Sources/SpyableMacro/Factories/SpyFactory.swift

@@ -92,7 +92,10 @@ struct SpyFactory {
   private let closureFactory = ClosureFactory()
   private let functionImplementationFactory = FunctionImplementationFactory()
 
-  func classDeclaration(for protocolDeclaration: ProtocolDeclSyntax) throws -> ClassDeclSyntax {
+  func classDeclaration(
+    for protocolDeclaration: ProtocolDeclSyntax,
+    inheritedType: String? = nil
+  ) throws -> ClassDeclSyntax {
     let identifier = TokenSyntax.identifier(protocolDeclaration.name.text + "Spy")
 
     let assosciatedtypeDeclarations = protocolDeclaration.memberBlock.members.compactMap {
@@ -117,6 +120,14 @@ struct SpyFactory {
       name: identifier,
       genericParameterClause: genericParameterClause,
       inheritanceClause: InheritanceClauseSyntax {
+        // Add inherited type first if present
+        if let inheritedType {
+          InheritedTypeSyntax(
+            type: TypeSyntax(stringLiteral: inheritedType)
+          )
+        }
+
+        // Add the main protocol
         InheritedTypeSyntax(
           type: TypeSyntax(stringLiteral: protocolDeclaration.name.text)
         )
@@ -125,7 +136,10 @@ struct SpyFactory {
         )
       },
       memberBlockBuilder: {
+        let initOverrideKeyword: DeclModifierListSyntax = inheritedType != nil ? [DeclModifierSyntax(name: .keyword(.override))] : []
+
         InitializerDeclSyntax(
+          modifiers: initOverrideKeyword,
           signature: FunctionSignatureSyntax(
             parameterClause: FunctionParameterClauseSyntax(parameters: [])
           ),

Sources/SpyableMacro/Macro/AccessLevelModifierRewriter.swift

@@ -17,8 +17,19 @@ final class AccessLevelModifierRewriter: SyntaxRewriter {
       return node
     }
 
-    return DeclModifierListSyntax {
-      newAccessLevel
+    // Always preserve existing modifiers (like override, convenience, etc.)
+    var modifiers = Array(node)
+    
+    // Special case: if accessLevel is open and this is an initializer, use public instead
+    if newAccessLevel.name.text == TokenSyntax.keyword(.open).text,
+       let parent = node.parent,
+       parent.is(InitializerDeclSyntax.self) {
+      modifiers.append(DeclModifierSyntax(name: .keyword(.public)))
+    } else {
+      // Add the access level modifier for all other cases
+      modifiers.append(newAccessLevel)
     }
+    
+    return DeclModifierListSyntax(modifiers)
   }
 }

Sources/SpyableMacro/Macro/SpyableMacro.swift

@@ -13,8 +13,14 @@ public enum SpyableMacro: PeerMacro {
     // Extract the protocol declaration
     let protocolDeclaration = try extractor.extractProtocolDeclaration(from: declaration)
 
-    // Generate the initial spy class declaration
-    var spyClassDeclaration = try spyFactory.classDeclaration(for: protocolDeclaration)
+    // Extract inherited type from the attribute
+    let inheritedType = extractor.extractInheritedType(from: node, in: context)
+
+    // Generate the initial spy class declaration with inherited type
+    var spyClassDeclaration = try spyFactory.classDeclaration(
+      for: protocolDeclaration,
+      inheritedType: inheritedType
+    )
 
     // Apply access level modifiers if needed
     if let accessLevel = determineAccessLevel(