From fe2b680be8bd6afbeb5ba7dddc67889c3a136dbc Mon Sep 17 00:00:00 2001
From: Svyatoslav Scherbina <svyatoslav.scherbina@jetbrains.com>
Date: Tue, 11 Dec 2018 09:49:56 +0300
Subject: [PATCH] Support C enums with forward declarations

---
 .../jetbrains/kotlin/native/interop/indexer/Indexer.kt |  8 +++++++-
 backend.native/tests/build.gradle                      | 10 +++++-----
 .../tests/interop/basics/{cstructs.def => ctypes.def}  |  7 ++++++-
 .../tests/interop/basics/{structs.kt => types.kt}      |  4 +++-
 backend.native/tests/interop/objc/smoke.h              |  5 +++++
 backend.native/tests/interop/objc/smoke.kt             |  2 ++
 6 files changed, 28 insertions(+), 8 deletions(-)
 rename backend.native/tests/interop/basics/{cstructs.def => ctypes.def} (73%)
 rename backend.native/tests/interop/basics/{structs.kt => types.kt} (71%)

diff --git a/Interop/Indexer/src/main/kotlin/org/jetbrains/kotlin/native/interop/indexer/Indexer.kt b/Interop/Indexer/src/main/kotlin/org/jetbrains/kotlin/native/interop/indexer/Indexer.kt
index f38f95be9a9..98e5ebdece4 100644
--- a/Interop/Indexer/src/main/kotlin/org/jetbrains/kotlin/native/interop/indexer/Indexer.kt
+++ b/Interop/Indexer/src/main/kotlin/org/jetbrains/kotlin/native/interop/indexer/Indexer.kt
@@ -240,7 +240,13 @@ internal class NativeIndexImpl(val library: NativeLibrary, val verbose: Boolean
 
     private fun getEnumDefAt(cursor: CValue<CXCursor>): EnumDefImpl {
         if (clang_isCursorDefinition(cursor) == 0) {
-            TODO("support enum forward declarations")
+            val definitionCursor = clang_getCursorDefinition(cursor)
+            if (clang_isCursorDefinition(definitionCursor) != 0) {
+                return getEnumDefAt(definitionCursor)
+            } else {
+                TODO("support enum forward declarations: " +
+                        clang_getTypeSpelling(clang_getCursorType(cursor)).convertAndDispose())
+            }
         }
 
         return enumRegistry.getOrPut(cursor) {
diff --git a/backend.native/tests/build.gradle b/backend.native/tests/build.gradle
index 373325fb3ad..863b91dfc03 100644
--- a/backend.native/tests/build.gradle
+++ b/backend.native/tests/build.gradle
@@ -2838,8 +2838,8 @@ kotlinNativeInterop {
         defFile 'interop/basics/cunsupported.def'
     }
 
-    cstructs {
-        defFile 'interop/basics/cstructs.def'
+    ctypes {
+        defFile 'interop/basics/ctypes.def'
     }
 
     if (isMac()) {
@@ -2935,10 +2935,10 @@ task interop_unsupported(type: RunInteropKonanTest) {
     interop = 'cunsupported'
 }
 
-task interop_structs(type: RunInteropKonanTest) {
+task interop_types(type: RunInteropKonanTest) {
     disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
-    source = "interop/basics/structs.kt"
-    interop = 'cstructs'
+    source = "interop/basics/types.kt"
+    interop = 'ctypes'
 }
 
 task interop_echo_server(type: RunInteropKonanTest) {
diff --git a/backend.native/tests/interop/basics/cstructs.def b/backend.native/tests/interop/basics/ctypes.def
similarity index 73%
rename from backend.native/tests/interop/basics/cstructs.def
rename to backend.native/tests/interop/basics/ctypes.def
index d085f15d611..181ab2d3be8 100644
--- a/backend.native/tests/interop/basics/cstructs.def
+++ b/backend.native/tests/interop/basics/ctypes.def
@@ -8,4 +8,9 @@ struct StructWithConstFields {
 struct StructWithConstFields getStructWithConstFields() {
     struct StructWithConstFields result = { 111, 222 };
     return result;
-}
\ No newline at end of file
+}
+
+enum ForwardDeclaredEnum;
+enum ForwardDeclaredEnum {
+    ZERO, ONE, TWO
+};
\ No newline at end of file
diff --git a/backend.native/tests/interop/basics/structs.kt b/backend.native/tests/interop/basics/types.kt
similarity index 71%
rename from backend.native/tests/interop/basics/structs.kt
rename to backend.native/tests/interop/basics/types.kt
index b340c34f723..03b8bec2aa5 100644
--- a/backend.native/tests/interop/basics/structs.kt
+++ b/backend.native/tests/interop/basics/types.kt
@@ -1,10 +1,12 @@
 import kotlinx.cinterop.*
 import kotlin.test.*
-import cstructs.*
+import ctypes.*
 
 fun main() {
     getStructWithConstFields().useContents {
         assertEquals(111, x)
         assertEquals(222, y)
     }
+
+    assertEquals(1u, ForwardDeclaredEnum.ONE.value)
 }
\ No newline at end of file
diff --git a/backend.native/tests/interop/objc/smoke.h b/backend.native/tests/interop/objc/smoke.h
index 5458a64cf9b..6a826097866 100644
--- a/backend.native/tests/interop/objc/smoke.h
+++ b/backend.native/tests/interop/objc/smoke.h
@@ -61,3 +61,8 @@ int formatStringLength(NSString* format, ...);
 
 #define STRING_MACRO @"String macro"
 #define CFSTRING_MACRO CFSTR("CFString macro")
+
+typedef NS_ENUM(int32_t, ForwardDeclaredEnum);
+typedef NS_ENUM(int32_t, ForwardDeclaredEnum) {
+    ZERO, ONE, TWO,
+};
\ No newline at end of file
diff --git a/backend.native/tests/interop/objc/smoke.kt b/backend.native/tests/interop/objc/smoke.kt
index 5bddbfa14a7..40a4a65bce9 100644
--- a/backend.native/tests/interop/objc/smoke.kt
+++ b/backend.native/tests/interop/objc/smoke.kt
@@ -19,6 +19,8 @@ fun run() {
     testConversions()
     testWeakRefs()
 
+    assertEquals(2, ForwardDeclaredEnum.TWO.value)
+
     println(
             getSupplier(
                     invoke1(42) { it * 2 }