[Interop] Additional simple mangling of special names such as Companion (#3919)

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/CodeUtils.kt

@@ -44,6 +44,22 @@ fun String.asSimpleName(): String = if (this in kotlinKeywords || this.contains(
     this
 }
 
+/**
+ * Yet another mangler, particularly to avoid secondary clash, e.g. when a property
+ * in prototype (interface) is mangled and that will cause another clash in the class
+ * which implements this interface.
+ * Rationale: keep algorithm simple but use the mangling characters which are rare
+ * in normal code, and keep mangling easy readable.
+ */
+internal fun mangleSimple(name: String): String {
+    val reserved = setOf("Companion")
+    val postfix = "\$"
+    return if (name in reserved)
+        "$name$postfix"
+    else
+        name
+}
+
 /**
  * Returns the expression to be parsed by Kotlin as string literal with given contents,
  * i.e. transforms `foo$bar` to `"foo\$bar"`.

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/Mappings.kt

@@ -407,6 +407,7 @@ fun mirror(declarationMapper: DeclarationMapper, type: Type): TypeMirror = when
     is EnumType -> {
         val pkg = declarationMapper.getPackageFor(type.def)
         val kotlinName = declarationMapper.getKotlinNameForValue(type.def)
+                .let { mangleSimple(it) } // enum class requires additional mangling
 
         when {
             declarationMapper.isMappedToStrict(type.def) -> {

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/ObjCStubs.kt

@@ -583,7 +583,7 @@ private class ObjCPropertyStubBuilder(
             is ObjCCategory -> ClassifierStubType(context.getKotlinClassFor(container.clazz, isMeta = property.getter.isClass))
         }
         val origin = StubOrigin.ObjCProperty(property, container)
-        return listOf(PropertyStub(property.name, kotlinType.toStubIrType(), kind, modality, receiver, origin = origin))
+        return listOf(PropertyStub(mangleSimple(property.name), kotlinType.toStubIrType(), kind, modality, receiver, origin = origin))
     }
 }
 

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrElementBuilders.kt

@@ -88,6 +88,7 @@ internal class StructStubBuilder(
                 val fieldRefType = context.mirror(field.type)
                 val unwrappedFieldType = field.type.unwrapTypedefs()
                 val origin = StubOrigin.StructMember(field)
+                val fieldName = mangleSimple(field.name)
                 if (unwrappedFieldType is ArrayType) {
                     val type = (fieldRefType as TypeMirror.ByValue).valueType
                     val annotations = if (platform == KotlinPlatform.JVM) {
@@ -103,7 +104,7 @@ internal class StructStubBuilder(
                     }
                     val kind = PropertyStub.Kind.Val(getter)
                     // TODO: Should receiver be added?
-                    PropertyStub(field.name, type.toStubIrType(), kind, annotations = annotations, origin = origin)
+                    PropertyStub(fieldName, type.toStubIrType(), kind, annotations = annotations, origin = origin)
                 } else {
                     val pointedType = fieldRefType.pointedType.toStubIrType()
                     val pointedTypeArgument = TypeArgumentStub(pointedType)
@@ -121,14 +122,14 @@ internal class StructStubBuilder(
                             }
                         }
                         val kind = PropertyStub.Kind.Var(getter, setter)
-                        PropertyStub(field.name, fieldRefType.argType.toStubIrType(), kind, origin = origin)
+                        PropertyStub(fieldName, fieldRefType.argType.toStubIrType(), kind, origin = origin)
                     } else {
                         val accessor = when (context.generationMode) {
                             GenerationMode.SOURCE_CODE -> PropertyAccessor.Getter.MemberAt(offset, hasValueAccessor = false)
                             GenerationMode.METADATA -> PropertyAccessor.Getter.ExternalGetter(listOf(AnnotationStub.CStruct.MemberAt(offset)))
                         }
                         val kind = PropertyStub.Kind.Val(accessor)
-                        PropertyStub(field.name, pointedType, kind, origin = origin)
+                        PropertyStub(fieldName, pointedType, kind, origin = origin)
                     }
                 }
             } catch (e: Throwable) {
@@ -141,6 +142,7 @@ internal class StructStubBuilder(
             val typeInfo = typeMirror.info
             val kotlinType = typeMirror.argType
             val signed = field.type.isIntegerTypeSigned()
+            val fieldName = mangleSimple(field.name)
             val kind = when (context.generationMode) {
                 GenerationMode.SOURCE_CODE -> {
                     val readBits = PropertyAccessor.Getter.ReadBits(field.offset, field.size, signed)
@@ -155,7 +157,7 @@ internal class StructStubBuilder(
                     PropertyStub.Kind.Var(readBits, writeBits)
                 }
             }
-            PropertyStub(field.name, kotlinType.toStubIrType(), kind, origin = StubOrigin.StructMember(field))
+            PropertyStub(fieldName, kotlinType.toStubIrType(), kind, origin = StubOrigin.StructMember(field))
         }
 
         val superClass = context.platform.getRuntimeType("CStructVar")
@@ -277,7 +279,7 @@ internal class EnumStubBuilder(
                 .mapIndexed { index, constant ->
                     val literal = context.tryCreateIntegralStub(enumDef.baseType, constant.value)
                             ?: error("Cannot create enum value ${constant.value} of type ${enumDef.baseType}")
-                    val entry = EnumEntryStub(constant.name, literal, StubOrigin.EnumEntry(constant), index)
+                    val entry = EnumEntryStub(mangleSimple(constant.name), literal, StubOrigin.EnumEntry(constant), index)
                     val aliases = aliasConstants
                             .filter { it.value == constant.value }
                             .map { constructAliasProperty(it, entry) }

backend.native/tests/build.gradle

@@ -3348,6 +3348,14 @@ createInterop("ccallbacksAndVarargs") {
     it.defFile 'interop/basics/ccallbacksAndVarargs.def'
 }
 
+createInterop("cmangling") {
+    it.defFile 'interop/basics/mangling.def'
+}
+
+createInterop("cmangling2") {
+    it.defFile 'interop/basics/mangling2.def'
+}
+
 if (PlatformInfo.isAppleTarget(project)) {
     createInterop("objcSmoke") {
         it.defFile 'interop/objc/objcSmoke.def'
@@ -3505,6 +3513,18 @@ interopTest("interop_types") {
     interop = 'ctypes'
 }
 
+interopTest("interop_mangling") {
+    disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
+    source = "interop/basics/mangling.kt"
+    interop = 'cmangling'
+}
+
+interopTest("interop_mangling2") {
+    disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
+    source = "interop/basics/mangling2.kt"
+    interop = 'cmangling2'
+}
+
 interopTest("interop_values") {
     disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
     source = "interop/basics/values.kt"

backend.native/tests/interop/basics/mangling.def

@@ -0,0 +1,6 @@
+---
+
+// test mangling of special names
+
+enum _Companion {Companion, Any};
+enum _Companion companion = Companion;

backend.native/tests/interop/basics/mangling.kt

@@ -0,0 +1,9 @@
+import kotlinx.cinterop.*
+import kotlin.test.*
+import mangling.*
+
+fun main() {
+    companion = _Companion.`Companion$`
+    assertEquals(_Companion.`Companion$`, companion)
+}
+

backend.native/tests/interop/basics/mangling2.def

@@ -0,0 +1,6 @@
+---
+
+// test mangling of special names
+
+enum Companion {One, Two};
+

backend.native/tests/interop/basics/mangling2.kt

@@ -0,0 +1,9 @@
+import kotlinx.cinterop.*
+import kotlin.test.*
+import mangling2.*
+
+fun main() {
+    val mangled = `Companion$`.Two
+    assertEquals(`Companion$`.Two, mangled)
+}
+

backend.native/tests/interop/objc/smoke.h

@@ -249,3 +249,27 @@ extern BOOL customStringDeallocated;
 - (int)instanceMethod;
 + (int)classMethod:(int)first :(int)second;
 @end;
+
+// [KT-36067] cinterop tool fails when there is a structure member named Companion
+
+struct EnumFieldMangleStruct {
+	enum {Companion, Any} smth;
+};
+struct EnumFieldMangleStruct enumMangledStruct = { Any };
+
+struct MyStruct {
+	int Companion;      // simple clash
+	int _Companion;
+	int $_Companion;
+	int super;
+};
+
+struct MyStruct myStruct = {11, 12, 13, 14};
+
+@protocol Proto
+@property int Companion;  // clash on implementing
+@end;
+
+@interface FooMangled : NSObject<Proto>
+//- (void) CompanionS;  // mangleSimple does not support this: it may clash after mangling
+@end;

backend.native/tests/interop/objc/smoke.kt

@@ -33,6 +33,7 @@ fun run() {
     testLocalizedStrings()
     testConstructorReturnsNull()
     testCallableReferences()
+    testMangling()
 
     assertEquals(2, ForwardDeclaredEnum.TWO.value)
 
@@ -514,6 +515,21 @@ fun testCallableReferences() {
     assertEquals(42, boundInstanceMethodRef())
 }
 
+fun testMangling() {
+    assertEquals(11, myStruct.`Companion$`)
+    assertEquals(12, myStruct._Companion)
+    assertEquals(13, myStruct.`$_Companion`)
+    assertEquals(14, myStruct.`super`)
+
+    val objc = FooMangled()
+    objc.`Companion$` = 99
+    assertEquals(99, objc.Companion())
+    assertEquals(99, objc.`Companion$`)
+
+    enumMangledStruct.smth = Companion
+    assertEquals(Companion, enumMangledStruct.smth)
+}
+
 private val Any.objCClassName: String
     get() = object_getClassName(this)!!.toKString()
 

backend.native/tests/interop/objc/smoke.m

@@ -336,3 +336,9 @@ BOOL customStringDeallocated = NO;
     return first + second;
 }
 @end;
+
+
+// [KT-36067] mangling
+@implementation FooMangled : NSObject
+@synthesize Companion;
+@end;