fix handling of String in tuples

Author: ktoso

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+JavaTranslation.swift

@@ -1186,13 +1186,16 @@ extension JNISwift2JavaGenerator {
         // FIXME: More accurate determination of whether the result is direct or indirect
         if elementResult.outParameters.isEmpty {
           // Convert direct result to indirect result.
-          // For class types (nominal types), the JNI native representation is 'long'
-          // (a memory address), not the wrapper class type
+          // For most class types (Swift wrapper classes), the JNI native representation
+          // is 'long' (a memory address). However, String is a native JNI reference
+          // type and must keep its original type so the out-parameter array matches
+          // the native method signature (String[] not long[])
           let nativeElementType: JavaType
-          switch elementResult.javaType {
-          case .class:
+          if elementResult.javaType.isString {
+            nativeElementType = elementResult.javaType
+          } else if case .class = elementResult.javaType {
             nativeElementType = .long
-          default:
+          } else {
             nativeElementType = elementResult.javaType
           }
           let arrayType: JavaType = .array(nativeElementType)

Tests/JExtractSwiftTests/JNI/JNIGenericCombinationTests.swift

@@ -234,7 +234,7 @@ struct JNIGenericCombinationTests {
         expectedChunks: [
           """
           public static org.swift.swiftkit.core.tuple.Tuple2<java.lang.String, java.lang.Long> takeValues(org.swift.swiftkit.core.tuple.Tuple2<MyID<java.lang.String>, MyID<java.lang.Long>> tuple) {
-            long[] result_0$ = new long[1];
+            java.lang.String[] result_0$ = new java.lang.String[1];
             long[] result_1$ = new long[1];
             SwiftModule.$takeValues(tuple.$0.$memoryAddress(), tuple.$1.$memoryAddress(), result_0$, result_1$);
             return new org.swift.swiftkit.core.tuple.Tuple2<java.lang.String, java.lang.Long>(result_0$[0], result_1$[0]);

Tests/JExtractSwiftTests/JNI/JNITupleTests.swift

@@ -34,7 +34,7 @@ struct JNITupleTests {
         """
         public static org.swift.swiftkit.core.tuple.Tuple2<java.lang.Long, java.lang.String> returnPair() {
           long[] result_0$ = new long[1];
-          long[] result_1$ = new long[1];
+          java.lang.String[] result_1$ = new java.lang.String[1];
           SwiftModule.$returnPair(result_0$, result_1$);
           return new org.swift.swiftkit.core.tuple.Tuple2<java.lang.Long, java.lang.String>(result_0$[0], result_1$[0]);
         }