jextract: add support for arrays

Samples/SwiftJavaExtractJNISampleApp/Sources/MySwiftLibrary/Arrays.swift

@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import SwiftJava
+
+public func booleanArray(array: [Bool]) -> [Bool] {
+  return array
+}
+
+public func byteArray(array: [UInt8]) -> [UInt8] {
+  return array
+}
+
+public func byteArrayExplicit(array: Array<UInt8>) -> Array<UInt8> {
+  return array
+}
+
+public func charArray(array: [UInt16]) -> [UInt16] {
+  return array
+}
+
+public func shortArray(array: [Int16]) -> [Int16] {
+  return array
+}
+
+public func intArray(array: [Int32]) -> [Int32] {
+  return array
+}
+
+public func longArray(array: [Int64]) -> [Int64] {
+  return array
+}
+
+public func floatArray(array: [Float]) -> [Float] {
+  return array
+}
+
+public func doubleArray(array: [Double]) -> [Double] {
+  return array
+}
+
+public func stringArray(array: [String]) -> [String] {
+  return array
+}
+
+public func objectArray(array: [MySwiftClass]) -> [MySwiftClass] {
+  return array
+}
+

Samples/SwiftJavaExtractJNISampleApp/src/test/java/com/example/swift/ArraysTest.java

@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift.org project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of Swift.org project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+package com.example.swift;
+
+import org.junit.jupiter.api.Test;
+import org.swift.swiftkit.core.SwiftArena;
+
+import java.util.OptionalLong;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class ArraysTest {
+    @Test
+    void booleanArray() {
+        boolean[] input = new boolean[] { true, false, false, true };
+        assertArrayEquals(input, MySwiftLibrary.booleanArray(input));
+    }
+
+    @Test
+    void byteArray() {
+        byte[] input = new byte[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.byteArray(input));
+    }
+
+    @Test
+    void byteArray_empty() {
+        byte[] input = new byte[] {};
+        assertArrayEquals(input, MySwiftLibrary.byteArray(input));
+    }
+
+    @Test
+    void byteArray_null() {
+        assertThrows(NullPointerException.class, () -> MySwiftLibrary.byteArray(null));
+    }
+
+    @Test
+    void byteArrayExplicit() {
+        byte[] input = new byte[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.byteArrayExplicit(input));
+    }
+
+    @Test
+    void charArray() {
+        char[] input = new char[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.charArray(input));
+    }
+
+    @Test
+    void shortArray() {
+        short[] input = new short[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.shortArray(input));
+    }
+
+    @Test
+    void intArray() {
+        int[] input = new int[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.intArray(input));
+    }
+
+    @Test
+    void longArray() {
+        long[] input = new long[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.longArray(input));
+    }
+
+    @Test
+    void stringArray() {
+        String[] input = new String[] { "hey", "there", "my", "friend" };
+        assertArrayEquals(input, MySwiftLibrary.stringArray(input));
+    }
+
+    @Test
+    void floatArray() {
+        float[] input = new float[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.floatArray(input));
+    }
+
+    @Test
+    void doubleArray() {
+        double[] input = new double[] { 10, 20, 30, 40 };
+        assertArrayEquals(input, MySwiftLibrary.doubleArray(input));
+    }
+
+    @Test
+    void objectArray() {
+        try (var arena = SwiftArena.ofConfined()) {
+            MySwiftClass[] input = new MySwiftClass[]{MySwiftClass.init(arena), MySwiftClass.init(arena), MySwiftClass.init(arena) };
+            assertEquals(3, MySwiftLibrary.objectArray(input, arena).length);
+        }
+    }
+}

Sources/JExtractSwiftLib/CodePrinter.swift

@@ -86,12 +86,17 @@ public struct CodePrinter {
 
   public mutating func printBraceBlock(
     _ header: Any,
+    parameters: [String]? = nil,
     function: String = #function,
     file: String = #fileID,
     line: UInt = #line,
     body: (inout CodePrinter) throws -> ()
   ) rethrows {
-    print("\(header) {")
+    print("\(header) {", .continue)
+    if let parameters {
+      print(" (\(parameters.joined(separator: ", "))) in", .continue)
+    }
+    println()
     indent()
     try body(&self)
     outdent()

Sources/JExtractSwiftLib/FFM/CDeclLowering/CRepresentation.swift

@@ -68,7 +68,7 @@ extension CType {
     case .optional(let wrapped) where wrapped.isPointer:
       try self.init(cdeclType: wrapped)
 
-    case .genericParameter, .metatype, .optional, .tuple, .opaque, .existential, .composite:
+    case .genericParameter, .metatype, .optional, .tuple, .opaque, .existential, .composite, .array:
       throw CDeclToCLoweringError.invalidCDeclType(cdeclType)
     }
   }
@@ -127,7 +127,7 @@ extension SwiftKnownTypeDeclKind {
     case .void: .void
     case .unsafePointer, .unsafeMutablePointer, .unsafeRawBufferPointer, .unsafeMutableRawBufferPointer, 
       .unsafeBufferPointer, .unsafeMutableBufferPointer, .string, .foundationData, .foundationDataProtocol, 
-      .essentialsData, .essentialsDataProtocol, .optional:
+      .essentialsData, .essentialsDataProtocol, .optional, .array:
        nil
     }
   }

Sources/JExtractSwiftLib/FFM/CDeclLowering/FFMSwift2JavaGenerator+FunctionLowering.swift

@@ -347,6 +347,9 @@ struct CdeclLowering {
 
     case .composite:
       throw LoweringError.unhandledType(type)
+
+    case .array:
+      throw LoweringError.unhandledType(type)
     }
   }
 
@@ -415,7 +418,7 @@ struct CdeclLowering {
       }
       throw LoweringError.unhandledType(.optional(wrappedType))
 
-    case .function, .metatype, .optional, .composite:
+    case .function, .metatype, .optional, .composite, .array:
       throw LoweringError.unhandledType(.optional(wrappedType))
     }
   }
@@ -516,7 +519,7 @@ struct CdeclLowering {
       // Custom types are not supported yet.
       throw LoweringError.unhandledType(type)
 
-    case .genericParameter, .function, .metatype, .optional, .tuple, .existential, .opaque, .composite:
+    case .genericParameter, .function, .metatype, .optional, .tuple, .existential, .opaque, .composite, .array:
       // TODO: Implement
       throw LoweringError.unhandledType(type)
     }
@@ -670,7 +673,7 @@ struct CdeclLowering {
         conversion: .tupleExplode(conversions, name: outParameterName)
       )
 
-    case .genericParameter, .function, .optional, .existential, .opaque, .composite:
+    case .genericParameter, .function, .optional, .existential, .opaque, .composite, .array:
       throw LoweringError.unhandledType(type)
     }
   }

Sources/JExtractSwiftLib/FFM/FFMSwift2JavaGenerator+JavaTranslation.swift

@@ -475,6 +475,9 @@ extension FFMSwift2JavaGenerator {
 
       case .composite:
         throw JavaTranslationError.unhandledType(swiftType)
+
+      case .array(let elementType):
+        throw JavaTranslationError.unhandledType(swiftType)
       }
     }
 
@@ -694,7 +697,7 @@ extension FFMSwift2JavaGenerator {
         // TODO: Implement.
         throw JavaTranslationError.unhandledType(swiftType)
 
-      case .genericParameter, .optional, .function, .existential, .opaque, .composite:
+      case .genericParameter, .optional, .function, .existential, .opaque, .composite, .array:
         throw JavaTranslationError.unhandledType(swiftType)
       }
 

Sources/JExtractSwiftLib/JNI/JNIJavaTypeTranslator.swift

@@ -45,13 +45,14 @@ enum JNIJavaTypeTranslator {
     case .void: return .void
 
     case .string: return .javaLangString
+
     case .int, .uint, // FIXME: why not supported int/uint?
         .unsafeRawPointer, .unsafeMutableRawPointer,
         .unsafePointer, .unsafeMutablePointer,
         .unsafeRawBufferPointer, .unsafeMutableRawBufferPointer,
         .unsafeBufferPointer, .unsafeMutableBufferPointer,
-        .optional, .foundationData, .foundationDataProtocol, .essentialsData, .essentialsDataProtocol:
+        .optional, .foundationData, .foundationDataProtocol, .essentialsData, .essentialsDataProtocol, .array:
       return nil
     }
   }
-}
+}

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+JavaBindingsPrinting.swift

@@ -25,7 +25,7 @@ extension JNISwift2JavaGenerator {
     "java.util.concurrent.atomic.AtomicBoolean",
 
     // NonNull, Unsigned and friends
-    "org.swift.swiftkit.core.annotations.*",
+    "org.swift.swiftkit.core.annotations.*"
   ]
 }