Make SwiftNominalType.genericArguments non-optional

Sources/JExtractSwiftLib/FFM/FFMSwift2JavaGenerator+JavaTranslation.swift

@@ -476,7 +476,7 @@ extension FFMSwift2JavaGenerator {
         }
 
         // Generic types are not supported yet.
-        guard swiftNominalType.genericArguments == nil else {
+        guard swiftNominalType.genericArguments.isEmpty else {
           throw JavaTranslationError.unhandledType(swiftType)
         }
 
@@ -821,7 +821,7 @@ extension FFMSwift2JavaGenerator {
         }
 
         // Generic types are not supported yet.
-        guard swiftNominalType.genericArguments == nil else {
+        guard swiftNominalType.genericArguments.isEmpty else {
           throw JavaTranslationError.unhandledType(swiftType)
         }
 

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+JavaTranslation.swift

@@ -481,13 +481,13 @@ extension JNISwift2JavaGenerator {
         let javaType = JavaType.class(
           package: moduleJavaPackages[nominalType.nominalTypeDecl.moduleName],
           name: nominalTypeName,
-          typeParameters: try nominalType.genericArguments?.map { swiftType in
+          typeParameters: try nominalType.genericArguments.map { swiftType in
             try translateGenericTypeParameter(
               swiftType,
               genericParameters: genericParameters,
               genericRequirements: genericRequirements,
             )
-          } ?? [],
+          },
         )
 
         // We assume this is a JExtract class.
@@ -918,13 +918,13 @@ extension JNISwift2JavaGenerator {
         let javaType = JavaType.class(
           package: moduleJavaPackages[nominalType.nominalTypeDecl.moduleName],
           name: nominalType.nominalTypeDecl.qualifiedName,
-          typeParameters: try nominalType.genericArguments?.map { swiftType in
+          typeParameters: try nominalType.genericArguments.map { swiftType in
             try translateGenericTypeParameter(
               swiftType,
               genericParameters: genericParameters,
               genericRequirements: genericRequirements,
             )
-          } ?? [],
+          },
         )
 
         // We assume this is a JExtract class.
@@ -1062,13 +1062,13 @@ extension JNISwift2JavaGenerator {
 
         // We assume this is a JExtract class.
         let typeParameters =
-          try nominalType.genericArguments?.map { swiftType in
+          try nominalType.genericArguments.map { swiftType in
             try translateGenericTypeParameter(
               swiftType,
               genericParameters: genericParameters,
               genericRequirements: genericRequirements,
             )
-          } ?? []
+          }
 
         return .class(
           package: moduleJavaPackages[nominalType.nominalTypeDecl.moduleName],

Sources/JExtractSwiftLib/Swift2JavaTranslator.swift

@@ -181,10 +181,8 @@ extension Swift2JavaTranslator {
     func check(_ type: SwiftType) -> Bool {
       switch type {
       case .nominal(let nominal):
-        if let genericArguments = nominal.genericArguments {
-          if genericArguments.contains(where: check) {
-            return true
-          }
+        if nominal.genericArguments.contains(where: check) {
+          return true
         }
         return predicate(nominal.nominalTypeDecl)
       case .tuple(let tuple):

Sources/JExtractSwiftLib/SwiftTypes/SwiftType.swift

@@ -200,13 +200,13 @@ struct SwiftNominalType: Equatable {
   private var storedParent: Parent?
   var sugarName: SugarName?
   var nominalTypeDecl: SwiftNominalTypeDeclaration
-  var genericArguments: [SwiftType]?
+  var genericArguments: [SwiftType]
 
   init(
     parent: SwiftNominalType? = nil,
     sugarName: SugarName? = nil,
     nominalTypeDecl: SwiftNominalTypeDeclaration,
-    genericArguments: [SwiftType]? = nil
+    genericArguments: [SwiftType] = []
   ) {
     self.storedParent =
       parent.map { .nominal($0) } ?? nominalTypeDecl.parent.map { .nominal(SwiftNominalType(nominalTypeDecl: $0)) }
@@ -242,15 +242,15 @@ extension SwiftNominalType: CustomStringConvertible {
     switch sugarName {
     case .none:
       resultString += nominalTypeDecl.name
-      if let genericArguments {
+      if !genericArguments.isEmpty {
         resultString += "<\(genericArguments.map(\.description).joined(separator: ", "))>"
       }
     case .some(.optional):
-      resultString += "\(genericArguments![0])?"
+      resultString += "\(genericArguments[0])?"
     case .some(.array):
-      resultString += "[\(genericArguments![0])]"
+      resultString += "[\(genericArguments[0])]"
     case .some(.dictionary):
-      resultString += "[\(genericArguments![0]): \(genericArguments![1])]"
+      resultString += "[\(genericArguments[0]): \(genericArguments[1])]"
     }
 
     return resultString
@@ -345,7 +345,7 @@ extension SwiftType {
         originalType: type,
         parent: nil,
         name: identifierType.name,
-        genericArguments: genericArgs,
+        genericArguments: genericArgs ?? [],
         lookupContext: lookupContext
       )
 
@@ -383,7 +383,7 @@ extension SwiftType {
         originalType: type,
         parent: parentType,
         name: memberType.name,
-        genericArguments: genericArgs,
+        genericArguments: genericArgs ?? [],
         lookupContext: lookupContext,
         module: moduleName
       )
@@ -433,7 +433,7 @@ extension SwiftType {
     originalType: TypeSyntax,
     parent: SwiftType?,
     name: TokenSyntax,
-    genericArguments: [SwiftType]?,
+    genericArguments: [SwiftType],
     lookupContext: SwiftTypeLookupContext,
     module: String? = nil
   ) throws {
@@ -471,7 +471,7 @@ extension SwiftType {
     } else if let aliasDecl = typeDecl as? SwiftTypeAliasDeclaration {
       let aliasGenericParams =
         aliasDecl.syntax.genericParameterClause?.parameters.map { $0.name.text } ?? []
-      let useSiteArgs = genericArguments ?? []
+      let useSiteArgs = genericArguments
 
       // The alias's generic parameter count must match the use-site argument
       // count. Treat any mismatch (including use-site args on a non-generic
@@ -514,7 +514,7 @@ extension SwiftType {
       SwiftNominalType(
         parent: parent?.asNominalType,
         nominalTypeDecl: nominalTypeDecl,
-        genericArguments: nil
+        genericArguments: []
       )
     )
   }
@@ -533,7 +533,7 @@ extension SwiftType {
           parent: nominal.parent,
           sugarName: nominal.sugarName,
           nominalTypeDecl: nominal.nominalTypeDecl,
-          genericArguments: nominal.genericArguments?.map {
+          genericArguments: nominal.genericArguments.map {
             $0.substituting(genericParameters: substitutions)
           }
         )
@@ -596,7 +596,7 @@ extension SwiftNominalTypeDeclaration {
     return SwiftNominalType(
       parent: parent?.asSwiftNominalType,
       nominalTypeDecl: self,
-      genericArguments: genericArguments.isEmpty ? nil : genericArguments
+      genericArguments: genericArguments
     )
   }
 

Tests/JExtractSwiftTests/TypealiasResolutionTests.swift

@@ -126,7 +126,7 @@ struct TypealiasResolutionTests {
       return
     }
     #expect(nominal.nominalTypeDecl.name == "Optional")
-    let arg0 = try #require(nominal.genericArguments?.first)
+    let arg0 = try #require(nominal.genericArguments.first)
     #expect(arg0.description == "Int64", "Expected substituted T to be Int64, got \(arg0)")
   }
 
@@ -154,7 +154,7 @@ struct TypealiasResolutionTests {
       return
     }
     #expect(nominal.nominalTypeDecl.name == "Dictionary")
-    let args = try #require(nominal.genericArguments)
+    let args = nominal.genericArguments
     #expect(args.count == 2)
     #expect(args[0].description == "String")
     #expect(args[1].description == "Int64")
@@ -295,7 +295,7 @@ struct TypealiasResolutionTests {
       return
     }
     #expect(nominal.nominalTypeDecl.name == "Optional")
-    #expect(nominal.genericArguments?.first?.description == "Int64")
+    #expect(nominal.genericArguments.first?.description == "Int64")
   }
 
   @Test("Typealias to array sugar resolves to an array")
@@ -320,7 +320,7 @@ struct TypealiasResolutionTests {
       return
     }
     #expect(nominal.nominalTypeDecl.name == "Array")
-    #expect(nominal.genericArguments?.first?.description == "Int8")
+    #expect(nominal.genericArguments.first?.description == "Int8")
   }
 
   // ==== -----------------------------------------------------------------------
@@ -410,7 +410,7 @@ struct TypealiasResolutionTests {
       return
     }
     #expect(nominal.nominalTypeDecl.name == "Optional")
-    #expect(nominal.genericArguments?.first?.description == "Int64")
+    #expect(nominal.genericArguments.first?.description == "Int64")
   }
 
   // ==== -----------------------------------------------------------------------