Fix jextract subdirectory handling in input Sources

Plugins/JExtractSwiftPlugin/JExtractSwiftPlugin.swift

@@ -93,7 +93,7 @@ struct JExtractSwiftBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
       $0.pathExtension == "swift"
     }
 
-    // Output Swift files are just Java filename based converted to Swift files one-to-one
+    // Output files are flattened filenames of the inputs, with the appended +SwiftJava suffix.
     var outputSwiftFiles: [URL] = swiftFiles.compactMap { sourceFileURL in
       guard sourceFileURL.isFileURL else {
         return nil as URL?
@@ -104,7 +104,6 @@ struct JExtractSwiftBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
         fatalError("Could not get relative path for source file \(sourceFilePath)")
       }
       let outputURL = outputSwiftDirectory
-        .appending(path: String(sourceFilePath.dropFirst(sourceDir.count).dropLast(sourceFileURL.lastPathComponent.count + 1)))
 
       let inputFileName = sourceFileURL.deletingPathExtension().lastPathComponent
       return outputURL.appending(path: "\(inputFileName)+SwiftJava.swift")

Plugins/SwiftJavaPlugin/SwiftJavaPlugin.swift

@@ -175,6 +175,10 @@ struct SwiftJavaBuildToolPlugin: SwiftJavaPluginProtocol, BuildToolPlugin {
 
       let displayName = "Wrapping \(classes.count) Java classes in Swift target '\(sourceModule.name)'"
       log("Prepared: \(displayName)")
+
+      for f in outputSwiftFiles {
+        log("Swift output file: \(f)")
+      }
       commands += [
         .buildCommand(
           displayName: displayName,

Samples/SwiftJavaExtractFFMSampleApp/Sources/MySwiftLibrary/LibrarySubDirectory/SwiftTypeInSubDirectory.swift

@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 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
+//
+//===----------------------------------------------------------------------===//
+
+public final class SwiftTypeInSubDirectory {
+  public init() {}
+
+  public func hello() -> Int {
+    12
+  }
+}

Samples/SwiftJavaExtractFFMSampleApp/Sources/MySwiftLibrary/swift-java.config

@@ -1,3 +1,4 @@
 {
-  "javaPackage": "com.example.swift"
+  "javaPackage": "com.example.swift",
+  "logLevel": "trace"
 }

Samples/SwiftJavaExtractFFMSampleApp/src/test/java/com/example/swift/SwiftTypeInSubDirectoryTest.java

@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 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.Disabled;
+import org.junit.jupiter.api.Test;
+import org.swift.swiftkit.core.SwiftLibraries;
+import org.swift.swiftkit.ffm.AllocatingSwiftArena;
+
+import java.io.File;
+import java.util.stream.Stream;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class SwiftTypeInSubDirectoryTest {
+
+    @Test
+    void test_MySwiftClass_voidMethod() {
+        try (var arena = AllocatingSwiftArena.ofConfined()) {
+            SwiftTypeInSubDirectory o = SwiftTypeInSubDirectory.init(arena);
+            var num = o.hello();
+            assertEquals(12, num);
+        }
+    }
+
+}

Samples/SwiftJavaExtractJNISampleApp/Sources/MySwiftLibrary/LibrarySubDirectory/SwiftTypeInSubDirectory.swift

@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 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
+//
+//===----------------------------------------------------------------------===//
+
+public final class SwiftTypeInSubDirectory {
+  public init() {}
+
+  public func hello() -> Int {
+    12
+  }
+}

Samples/SwiftJavaExtractJNISampleApp/Sources/MySwiftLibrary/swift-java.config

@@ -1,5 +1,5 @@
 {
   "javaPackage": "com.example.swift",
   "mode": "jni",
-  "logLevel": ["debug"]
+  "logLevel": "debug"
 }

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

@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 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 static org.junit.jupiter.api.Assertions.*;
+
+public class SwiftTypeInSubDirectoryTest {
+
+    @Test
+    void test_SwiftTypeInSubDirectory_hello() {
+        try (var arena = SwiftArena.ofConfined()) {
+            SwiftTypeInSubDirectory o = SwiftTypeInSubDirectory.init(arena);
+            var num = o.hello();
+            assertEquals(12, num);
+        }
+    }
+
+}

Sources/JExtractSwiftLib/CodePrinter.swift

@@ -14,7 +14,11 @@
 
 import Foundation
 
-let PATH_SEPARATOR = "/"  // TODO: Windows
+#if os(Windows)
+let PATH_SEPARATOR = "\\"
+#else
+let PATH_SEPARATOR = "/"
+#endif
 
 public struct CodePrinter {
   var contents: String = ""

Sources/JExtractSwiftLib/FFM/FFMSwift2JavaGenerator+SwiftThunkPrinting.swift

@@ -22,16 +22,15 @@ extension FFMSwift2JavaGenerator {
   }
 
   package func writeSwiftExpectedEmptySources() throws {
-    let pendingFileCount = self.expectedOutputSwiftFiles.count
+    let pendingFileCount = self.expectedOutputSwiftFileNames.count
     guard pendingFileCount > 0 else {
       return // no need to write any empty files, yay
     }
 
-    print("[swift-java] Write empty [\(self.expectedOutputSwiftFiles.count)] 'expected' files in: \(swiftOutputDirectory)/")
+    log.info("[swift-java] Write empty [\(self.expectedOutputSwiftFileNames.count)] 'expected' files in: \(swiftOutputDirectory)/")
 
-    for expectedFileName in self.expectedOutputSwiftFiles {
-      log.debug("Write SwiftPM-'expected' empty file: \(expectedFileName.bold)")
-
+    for expectedFileName in self.expectedOutputSwiftFileNames {
+      log.info("Write SwiftPM-'expected' empty file: \(expectedFileName.bold)")
 
       var printer = CodePrinter()
       printer.print("// Empty file generated on purpose")
@@ -55,7 +54,7 @@ extension FFMSwift2JavaGenerator {
         javaPackagePath: nil,
         filename: moduleFilename) {
         log.info("Generated: \(moduleFilenameBase.bold).swift (at \(outputFile.absoluteString))")
-        self.expectedOutputSwiftFiles.remove(moduleFilename)
+        self.expectedOutputSwiftFileNames.remove(moduleFilename)
       }
     } catch {
       log.warning("Failed to write to Swift thunks: \(moduleFilename)")
@@ -93,7 +92,9 @@ extension FFMSwift2JavaGenerator {
           javaPackagePath: nil,
           filename: filename) {
           log.info("Done writing Swift thunks to: \(outputFile.absoluteString)")
-          self.expectedOutputSwiftFiles.remove(filename)
+          // log.info("REMOVE FROM: \(expectedOutputSwiftFileNames)")
+          // log.info("REMOVE FROM THE: \(filename)")
+          self.expectedOutputSwiftFileNames.remove(filename)
         }
       } catch {
         log.warning("Failed to write to Swift thunks: \(filename), error: \(error)")

Sources/JExtractSwiftLib/FFM/FFMSwift2JavaGenerator.swift

@@ -39,7 +39,10 @@ package class FFMSwift2JavaGenerator: Swift2JavaGenerator {
 
   /// Because we need to write empty files for SwiftPM, keep track which files we didn't write yet,
   /// and write an empty file for those.
-  var expectedOutputSwiftFiles: Set<String>
+  /// 
+  /// Since Swift files in SwiftPM builds needs to be unique, we use this fact to flatten paths into plain names here.
+  /// For uniqueness checking "did we write this file already", just checking the name should be sufficient.
+  var expectedOutputSwiftFileNames: Set<String>
 
   package init(
     config: Configuration,
@@ -57,19 +60,26 @@ package class FFMSwift2JavaGenerator: Swift2JavaGenerator {
     self.javaOutputDirectory = javaOutputDirectory
     self.lookupContext = translator.lookupContext
 
-    // If we are forced to write empty files, construct the expected outputs
+    // If we are forced to write empty files, construct the expected outputs.
+    // It is sufficient to use file names only, since SwiftPM requires names to be unique within a module anyway.
     if translator.config.writeEmptyFiles ?? false {
-      self.expectedOutputSwiftFiles = Set(translator.inputs.compactMap { (input) -> String? in
-        guard let filePathPart = input.path.split(separator: "/\(translator.swiftModuleName)/").last else {
+      self.expectedOutputSwiftFileNames = Set(translator.inputs.compactMap { (input) -> String? in
+        // guard let filePathPart = input.path.split(separator: "/\(translator.swiftModuleName)/").last else {
+        //   return nil
+        // }
+        // return String(filePathPart.replacing(".swift", with: "+SwiftJava.swift"))
+        guard let fileName = input.path.split(separator: PATH_SEPARATOR).last else {
           return nil
         }
-
-        return String(filePathPart.replacing(".swift", with: "+SwiftJava.swift"))
+        guard fileName.hasSuffix(".swift") else {
+          return nil
+        }
+        return String(fileName.replacing(".swift", with: "+SwiftJava.swift"))
       })
-      self.expectedOutputSwiftFiles.insert("\(translator.swiftModuleName)Module+SwiftJava.swift")
-      self.expectedOutputSwiftFiles.insert("Foundation+SwiftJava.swift")
+      self.expectedOutputSwiftFileNames.insert("\(translator.swiftModuleName)Module+SwiftJava.swift")
+      self.expectedOutputSwiftFileNames.insert("Foundation+SwiftJava.swift")
     } else {
-      self.expectedOutputSwiftFiles = []
+      self.expectedOutputSwiftFileNames = []
     }
   }
 

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+SwiftThunkPrinting.swift

@@ -26,15 +26,15 @@ extension JNISwift2JavaGenerator {
   }
 
   package func writeSwiftExpectedEmptySources() throws {
-    let pendingFileCount = self.expectedOutputSwiftFiles.count
+    let pendingFileCount = self.expectedOutputSwiftFileNames.count
     guard pendingFileCount > 0 else {
       return // no need to write any empty files, yay
     }
-    
-    print("[swift-java] Write empty [\(self.expectedOutputSwiftFiles.count)] 'expected' files in: \(swiftOutputDirectory)/")
-    
-    for expectedFileName in self.expectedOutputSwiftFiles {
-      logger.debug("Write SwiftPM-'expected' empty file: \(expectedFileName.bold)")
+
+    logger.info("[swift-java] Write empty [\(self.expectedOutputSwiftFileNames.count)] 'expected' files in: \(swiftOutputDirectory)/")
+
+    for expectedFileName in self.expectedOutputSwiftFileNames {
+      logger.info("Write SwiftPM-'expected' empty file: \(expectedFileName.bold)")
 
 
       var printer = CodePrinter()
@@ -61,7 +61,7 @@ extension JNISwift2JavaGenerator {
         filename: moduleFilename
       ) {
         logger.info("Generated: \(moduleFilenameBase.bold).swift (at \(outputFile.absoluteString))")
-        self.expectedOutputSwiftFiles.remove(moduleFilename)
+        self.expectedOutputSwiftFileNames.remove(moduleFilename)
       }
 
       // === All types
@@ -96,7 +96,7 @@ extension JNISwift2JavaGenerator {
             javaPackagePath: nil,
             filename: filename) {
             logger.info("Done writing Swift thunks to: \(outputFile.absoluteString)")
-            self.expectedOutputSwiftFiles.remove(filename)
+            self.expectedOutputSwiftFileNames.remove(filename)
           }
         } catch {
           logger.warning("Failed to write to Swift thunks: \(filename), error: \(error)")

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator.swift

@@ -44,7 +44,10 @@ package class JNISwift2JavaGenerator: Swift2JavaGenerator {
 
   /// Because we need to write empty files for SwiftPM, keep track which files we didn't write yet,
   /// and write an empty file for those.
-  var expectedOutputSwiftFiles: Set<String>
+  ///
+  /// Since Swift files in SwiftPM builds needs to be unique, we use this fact to flatten paths into plain names here.
+  /// For uniqueness checking "did we write this file already", just checking the name should be sufficient.
+  var expectedOutputSwiftFileNames: Set<String>
 
   package init(
     config: Configuration,
@@ -64,27 +67,34 @@ package class JNISwift2JavaGenerator: Swift2JavaGenerator {
     self.javaClassLookupTable = javaClassLookupTable
     self.lookupContext = translator.lookupContext
 
-     // If we are forced to write empty files, construct the expected outputs
+    // If we are forced to write empty files, construct the expected outputs.
+    // It is sufficient to use file names only, since SwiftPM requires names to be unique within a module anyway.
     if translator.config.writeEmptyFiles ?? false {
-      self.expectedOutputSwiftFiles = Set(translator.inputs.compactMap { (input) -> String? in
-        guard let filePathPart = input.path.split(separator: "/\(translator.swiftModuleName)/").last else {
+      self.expectedOutputSwiftFileNames = Set(translator.inputs.compactMap { (input) -> String? in
+        // guard let filePathPart = input.path.split(separator: "/\(translator.swiftModuleName)/").last else {
+        //   return nil
+        // }
+        // return String(filePathPart.replacing(".swift", with: "+SwiftJava.swift"))
+        guard let fileName = input.path.split(separator: PATH_SEPARATOR).last else {
           return nil
         }
-
-        return String(filePathPart.replacing(".swift", with: "+SwiftJava.swift"))
+        guard fileName.hasSuffix(".swift") else {
+          return nil
+        }
+        return String(fileName.replacing(".swift", with: "+SwiftJava.swift"))
       })
-      self.expectedOutputSwiftFiles.insert("\(translator.swiftModuleName)Module+SwiftJava.swift")
-      self.expectedOutputSwiftFiles.insert("Foundation+SwiftJava.swift")
+      self.expectedOutputSwiftFileNames.insert("\(translator.swiftModuleName)Module+SwiftJava.swift")
+      self.expectedOutputSwiftFileNames.insert("Foundation+SwiftJava.swift")
     } else {
-      self.expectedOutputSwiftFiles = []
+      self.expectedOutputSwiftFileNames = []
     }
   }
 
   func generate() throws {
     try writeSwiftThunkSources()
     try writeExportedJavaSources()
 
-    let pendingFileCount = self.expectedOutputSwiftFiles.count
+    let pendingFileCount = self.expectedOutputSwiftFileNames.count
     if pendingFileCount > 0 {
       print("[swift-java] Write empty [\(pendingFileCount)] 'expected' files in: \(swiftOutputDirectory)/")
       try writeSwiftExpectedEmptySources()