[ObjCExport] Support objcExportBlockExplicitParameterNames in K2 version

^KT-77488 Fixed

Author: sbogolepov

native/analysis-api-based-export-common/src/org/jetbrains/kotlin/analysis/api/export/utilities/parameterNameAnnotation.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2010-2025 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.analysis.api.export.utilities
+
+import org.jetbrains.kotlin.analysis.api.annotations.KaAnnotation
+import org.jetbrains.kotlin.analysis.api.annotations.KaAnnotationValue
+import org.jetbrains.kotlin.analysis.api.types.KaType
+import org.jetbrains.kotlin.builtins.StandardNames
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.name.StandardClassIds
+
+public fun KaType.getValueFromParameterNameAnnotation(): Name? {
+    val resultingAnnotation = findParameterNameAnnotation() ?: return null
+    val parameterNameArgument = resultingAnnotation.arguments
+        .singleOrNull { it.name == StandardClassIds.Annotations.ParameterNames.parameterNameName }
+
+    val constantArgumentValue = parameterNameArgument?.expression as? KaAnnotationValue.ConstantValue ?: return null
+
+    return (constantArgumentValue.value.value as? String)?.let(Name::identifier)
+}
+
+private fun KaType.findParameterNameAnnotation(): KaAnnotation? {
+    val allParameterNameAnnotations = annotations[StandardNames.FqNames.parameterNameClassId]
+    val (explicitAnnotations, implicitAnnotations) = allParameterNameAnnotations.partition { it.psi != null }
+
+    return explicitAnnotations.firstOrNull() ?: implicitAnnotations.singleOrNull()
+}

native/objcexport-header-generator/impl/analysis-api/src/org/jetbrains/kotlin/objcexport/KtObjCExportConfiguration.kt

@@ -22,5 +22,7 @@ data class KtObjCExportConfiguration(
      * - [org.jetbrains.kotlin.backend.konan.objcexport.ObjCExportNamingHelper.canBeSwiftInner]
      */
     val objcGenerics: Boolean = true,
+
+    val objcExportBlockExplicitParameterNames: Boolean = true,
 )
 

native/objcexport-header-generator/impl/analysis-api/src/org/jetbrains/kotlin/objcexport/mangling/mangleUtils.kt

@@ -1,6 +1,17 @@
 package org.jetbrains.kotlin.objcexport.mangling
 
+import org.jetbrains.kotlin.backend.konan.cKeywords
+import org.jetbrains.kotlin.objcexport.toValidObjCSwiftIdentifier
+
 internal fun String.mangleSelector(postfix: String): String {
     return if (this.contains(":")) this.replace(":", "$postfix:")
     else this + postfix
+}
+
+internal fun unifyName(initialName: String, usedNames: Set<String>): String {
+    var unique = initialName.toValidObjCSwiftIdentifier()
+    while (unique in usedNames || unique in cKeywords) {
+        unique += "_"
+    }
+    return unique
 }

native/objcexport-header-generator/impl/analysis-api/src/org/jetbrains/kotlin/objcexport/translateToObjCFunctionType.kt

@@ -1,12 +1,15 @@
 package org.jetbrains.kotlin.objcexport
 
+import org.jetbrains.kotlin.analysis.api.export.utilities.getValueFromParameterNameAnnotation
 import org.jetbrains.kotlin.analysis.api.types.KaFunctionType
 import org.jetbrains.kotlin.analysis.api.types.KaType
 import org.jetbrains.kotlin.backend.konan.objcexport.*
 import org.jetbrains.kotlin.objcexport.analysisApiUtils.isObjCVoid
+import org.jetbrains.kotlin.objcexport.mangling.unifyName
 
 internal fun ObjCExportContext.translateToObjCFunctionType(type: KaType, returnsVoid: Boolean): ObjCReferenceType {
     if (type !is KaFunctionType) return ObjCIdType
+    val usedNames = mutableSetOf<String>()
     val objCBlockPointerType = ObjCBlockPointerType(
         returnType = if (returnsVoid) {
             ObjCVoidType
@@ -16,8 +19,16 @@ internal fun ObjCExportContext.translateToObjCFunctionType(type: KaType, returns
             else translateToObjCReferenceType(returnType)
         },
         parameters = listOfNotNull(type.receiverType).plus(type.parameterTypes).map { parameterType ->
+            val name = if (this@translateToObjCFunctionType.exportSession.configuration.objcExportBlockExplicitParameterNames) {
+                val parameterName = parameterType.getValueFromParameterNameAnnotation()?.asString() ?: ""
+                val mangledName = unifyName(parameterName, usedNames)
+                usedNames += mangledName
+                mangledName
+            } else {
+                ""
+            }
             ObjCParameter(
-                "",
+                name,
                 null,
                 type = translateToObjCReferenceType(parameterType),
                 todo = null,

native/objcexport-header-generator/impl/analysis-api/src/org/jetbrains/kotlin/objcexport/translateToObjCParameters.kt

@@ -7,22 +7,14 @@ package org.jetbrains.kotlin.objcexport
 
 import org.jetbrains.kotlin.analysis.api.symbols.KaFunctionSymbol
 import org.jetbrains.kotlin.analysis.api.symbols.KaPropertySetterSymbol
-import org.jetbrains.kotlin.backend.konan.cKeywords
 import org.jetbrains.kotlin.backend.konan.objcexport.*
 import org.jetbrains.kotlin.name.StandardClassIds
 import org.jetbrains.kotlin.objcexport.analysisApiUtils.errorParameterName
 import org.jetbrains.kotlin.objcexport.extras.objCTypeExtras
 import org.jetbrains.kotlin.objcexport.extras.*
+import org.jetbrains.kotlin.objcexport.mangling.unifyName
 
 internal fun ObjCExportContext.translateToObjCParameters(symbol: KaFunctionSymbol, baseMethodBridge: MethodBridge): List<ObjCParameter> {
-    fun unifyName(initialName: String, usedNames: Set<String>): String {
-        var unique = initialName.toValidObjCSwiftIdentifier()
-        while (unique in usedNames || unique in cKeywords) {
-            unique += "_"
-        }
-        return unique
-    }
-
     val valueParametersAssociated = valueParametersAssociated(baseMethodBridge, symbol)
     val parameters = mutableListOf<ObjCParameter>()
     val usedNames = mutableSetOf<String>()

native/objcexport-header-generator/impl/analysis-api/test/org/jetbrains/kotlin/objcexport/testUtils/AnalysisApiHeaderGenerator.kt

@@ -53,6 +53,7 @@ object AnalysisApiHeaderGenerator : HeaderGenerator {
             withKtObjCExportSession(
                 KtObjCExportConfiguration(
                     frameworkName = configuration.frameworkName,
+                    objcExportBlockExplicitParameterNames = configuration.objcExportBlockExplicitParameterNames,
                 ),
                 moduleClassifier = { module ->
                     module == useSiteModule || module is KaLibraryModule && module in exportedLibraries

native/objcexport-header-generator/test/org/jetbrains/kotlin/backend/konan/tests/ObjCExportHeaderGeneratorTest.kt

@@ -650,11 +650,15 @@ class ObjCExportHeaderGeneratorTest(private val generator: HeaderGenerator) {
     }
 
     @Test
-    @TodoAnalysisApi
     fun `test - block with explicit parameter names`() {
         doTest(headersTestDataDir.resolve("blockWithExplicitParameterNames"))
     }
 
+    @Test
+    fun `test - block with no parameter names`() {
+        doTest(headersTestDataDir.resolve("blockWithNoParameterNames"), Configuration(objcExportBlockExplicitParameterNames = false))
+    }
+
     @Test
     fun `test - release keyword as method name`() {
         doTest(headersTestDataDir.resolve("releaseKeywordAsMethodName"))

native/objcexport-header-generator/testData/headers/blockWithNoParameterNames/!blockWithNoParameterNames.h

@@ -0,0 +1,39 @@
+#import <Foundation/NSArray.h>
+#import <Foundation/NSDictionary.h>
+#import <Foundation/NSError.h>
+#import <Foundation/NSObject.h>
+#import <Foundation/NSSet.h>
+#import <Foundation/NSString.h>
+#import <Foundation/NSValue.h>
+
+@class Foo;
+
+NS_ASSUME_NONNULL_BEGIN
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunknown-warning-option"
+#pragma clang diagnostic ignored "-Wincompatible-property-type"
+#pragma clang diagnostic ignored "-Wnullability"
+
+#pragma push_macro("_Nullable_result")
+#if !__has_feature(nullability_nullable_result)
+#undef _Nullable_result
+#define _Nullable_result _Nullable
+#endif
+
+__attribute__((objc_subclassing_restricted))
+@interface Foo : Base
+- (instancetype)init __attribute__((swift_name("init()"))) __attribute__((objc_designated_initializer));
++ (instancetype)new __attribute__((availability(swift, unavailable, message="use object initializers instead")));
+- (void)bar0Cb:(void (^)(Int *))cb __attribute__((swift_name("bar0(cb:)")));
+- (void)bar1Cb:(void (^)(Int *))cb __attribute__((swift_name("bar1(cb:)")));
+- (void)bar2Cb:(void (^)(Int *, Int *, NSString *))cb __attribute__((swift_name("bar2(cb:)")));
+- (void)bar3Cb:(void (^)(Int *, Int *, Double *))cb __attribute__((swift_name("bar3(cb:)")));
+@end
+
+@interface Foo (Extensions)
+- (void)bar4Cb:(void (^)(Int *, NSString *))cb __attribute__((swift_name("bar4(cb:)")));
+@end
+
+#pragma pop_macro("_Nullable_result")
+#pragma clang diagnostic pop
+NS_ASSUME_NONNULL_END

native/objcexport-header-generator/testData/headers/blockWithNoParameterNames/Foo.kt

@@ -0,0 +1,8 @@
+class Foo {
+    fun bar0(cb: (result: Int) -> Unit) = Unit
+    fun bar1(cb: (result: @ParameterName("a") Int) -> Unit) = Unit
+    fun bar2(cb: (a: Int, b: Int, c: String) -> Unit) = Unit
+    fun bar3(cb: (int: Int, int_: Int, double: Double) -> Unit) = Unit
+}
+
+fun Foo.bar4(cb: (int: Int, message: String) -> Unit) = Unit