jextract/jni: Always return (U)Int as long (#564)

* add 32-bit CI

* fix ABI name

* map `Int`through `(U)Int64` initializer

Author: madsodgaard

.github/workflows/pull_request.yml

@@ -192,7 +192,7 @@ jobs:
         swift_version: ['nightly-main']
         os_version: ['jammy']
         jdk_vendor: ['corretto']
-        sdk_triple: ['x86_64-unknown-linux-android28']
+        sdk_triple: ['x86_64-unknown-linux-android28', 'armv7-unknown-linux-android28']
         ndk_version: ['r27d']
     container:
       image: ${{ (contains(matrix.swift_version, 'nightly') && 'swiftlang/swift') || 'swift' }}:${{ matrix.swift_version }}-${{ matrix.os_version }}

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+NativeTranslation.swift

@@ -619,11 +619,22 @@ extension JNISwift2JavaGenerator {
               throw JavaTranslationError.unsupportedSwiftType(swiftResult.type)
             }
 
-            return NativeResult(
-              javaType: javaType,
-              conversion: .getJNIValue(.placeholder),
-              outParameters: []
-            )
+            if let indirectReturnType = JNIJavaTypeTranslator.indirectConversionStepSwiftType(
+              for: knownType,
+              from: knownTypes
+            ) {
+              return NativeResult(
+                javaType: javaType,
+                conversion: .getJNIValue(.labelessInitializer(.placeholder, swiftType: indirectReturnType)),
+                outParameters: []
+              )
+            } else {
+              return NativeResult(
+                javaType: javaType,
+                conversion: .getJNIValue(.placeholder),
+                outParameters: []
+              )
+            }
           }
         }
 
@@ -902,6 +913,9 @@ extension JNISwift2JavaGenerator {
 
     indirect case replacingPlaceholder(NativeSwiftConversionStep, placeholder: NativeSwiftConversionStep)
 
+    /// `SwiftType(inner)`
+    indirect case labelessInitializer(NativeSwiftConversionStep, swiftType: SwiftType)
+
     /// Returns the conversion string applied to the placeholder.
     func render(_ printer: inout CodePrinter, _ placeholder: String) -> String {
       // NOTE: 'printer' is used if the conversion wants to cause side-effects.
@@ -1396,6 +1410,10 @@ extension JNISwift2JavaGenerator {
       case .replacingPlaceholder(let inner, let newPlaceholder):
         let newPlaceholder = newPlaceholder.render(&printer, placeholder)
         return inner.render(&printer, newPlaceholder)
+
+      case .labelessInitializer(let inner, let swiftType):
+        let inner = inner.render(&printer, placeholder)
+        return "\(swiftType)(\(inner))"
       }
     }
   }

Tests/JExtractSwiftTests/JNI/JNIIntConversionChecksTests.swift

@@ -152,7 +152,7 @@ struct JNIIntConversionChecksTests {
           guard let self$ else {
             fatalError("self memory address was null in call to \\(#function)!")
           }
-          return self$.pointee.unsignedInt.getJNIValue(in: environment)
+          return UInt64(self$.pointee.unsignedInt).getJNIValue(in: environment)
         """
       ]
     )
@@ -210,7 +210,7 @@ struct JNIIntConversionChecksTests {
         guard let self$ else {
           fatalError("self memory address was null in call to \\(#function)!")
         }
-        return self$.pointee.dummyFunc(arg: Int(arg$indirect)).getJNIValue(in: environment)
+        return Int64(self$.pointee.dummyFunc(arg: Int(arg$indirect))).getJNIValue(in: environment)
         """,
       ]
     )
@@ -238,7 +238,7 @@ struct JNIIntConversionChecksTests {
         guard let self$ else {
           fatalError("self memory address was null in call to \\(#function)!")
         }
-        return self$.pointee.dummyFunc(arg: UInt(arg$indirect)).getJNIValue(in: environment)
+        return UInt64(self$.pointee.dummyFunc(arg: UInt(arg$indirect))).getJNIValue(in: environment)
         """,
       ]
     )