From a9d45a3f423f60fa5d1f977acb5c8df50198f27e Mon Sep 17 00:00:00 2001
From: Argyrios Kyrtzidis <akyrtzi@gmail.com>
Date: Mon, 16 Apr 2012 22:42:01 +0000
Subject: [PATCH] [libclang] Make sure that when we have multiple @class
 references in the same line, that later ones do not override the previous
 ones.

If we have:
   @class Foo, Bar;
source ranges for both start at '@', so 'Bar' will end up overriding
'Foo' even though the cursor location was at 'Foo'.

rdar://11257578

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154873 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/Index/get-cursor.m   |  7 +++++++
 tools/libclang/CIndex.cpp | 22 +++++++++++++++++++++-
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/test/Index/get-cursor.m b/test/Index/get-cursor.m
index b8d82ac70b..5ac3375988 100644
--- a/test/Index/get-cursor.m
+++ b/test/Index/get-cursor.m
@@ -67,6 +67,8 @@ void foo3(Test3 *test3) {
 @implementation Test4(Dido)
 @end
 
+@class Forw1, Forw2, Forw3;
+
 // RUN: c-index-test -cursor-at=%s:4:28 -cursor-at=%s:5:28 %s | FileCheck -check-prefix=CHECK-PROP %s
 // CHECK-PROP: ObjCPropertyDecl=foo1:4:26
 // CHECK-PROP: ObjCPropertyDecl=foo2:5:27
@@ -90,8 +92,13 @@ void foo3(Test3 *test3) {
 
 // RUN: c-index-test -cursor-at=%s:56:24 -cursor-at=%s:60:14 \
 // RUN:   -cursor-at=%s:65:20 -cursor-at=%s:67:25 \
+// RUN:   -cursor-at=%s:70:10 -cursor-at=%s:70:16 -cursor-at=%s:70:25 \
 // RUN:   %s | FileCheck -check-prefix=CHECK-SPELLRANGE %s
 // CHECK-SPELLRANGE: 56:8 ObjCInstanceMethodDecl=setFoo:withBar::56:8 Extent=[56:1 - 56:37] Spelling=setFoo:withBar: ([56:8 - 56:14][56:22 - 56:29]) Selector index=1
 // CHECK-SPELLRANGE: 60:3 ObjCMessageExpr=setFoo:withBar::56:8 Extent=[60:3 - 60:29] Spelling=setFoo:withBar: ([60:10 - 60:16][60:19 - 60:26]) Selector index=0
 // CHECK-SPELLRANGE: 65:12 ObjCCategoryDecl=Dido:65:12 Extent=[65:1 - 66:5] Spelling=Dido ([65:18 - 65:22])
 // CHECK-SPELLRANGE: 67:17 ObjCCategoryImplDecl=Dido:67:17 (Definition) Extent=[67:1 - 68:2] Spelling=Dido ([67:23 - 67:27])
+
+// CHECK-SPELLRANGE: 70:8 ObjCClassRef=Forw1:70:8 Extent=[70:8 - 70:13] Spelling=Forw1 ([70:8 - 70:13])
+// CHECK-SPELLRANGE: 70:15 ObjCClassRef=Forw2:70:15 Extent=[70:15 - 70:20] Spelling=Forw2 ([70:15 - 70:20])
+// CHECK-SPELLRANGE: 70:22 ObjCClassRef=Forw3:70:22 Extent=[70:22 - 70:27] Spelling=Forw3 ([70:22 - 70:27])
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index ec8fc01dd2..605cc8bdee 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -3632,9 +3632,29 @@ static enum CXChildVisitResult GetCursorVisitor(CXCursor cursor,
   
   if (clang_isDeclaration(cursor.kind)) {
     // Avoid having the implicit methods override the property decls.
-    if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(getCursorDecl(cursor)))
+    if (ObjCMethodDecl *MD
+          = dyn_cast_or_null<ObjCMethodDecl>(getCursorDecl(cursor))) {
       if (MD->isImplicit())
         return CXChildVisit_Break;
+
+    } else if (ObjCInterfaceDecl *ID
+                 = dyn_cast_or_null<ObjCInterfaceDecl>(getCursorDecl(cursor))) {
+      // Check that when we have multiple @class references in the same line,
+      // that later ones do not override the previous ones.
+      // If we have:
+      // @class Foo, Bar;
+      // source ranges for both start at '@', so 'Bar' will end up overriding
+      // 'Foo' even though the cursor location was at 'Foo'.
+      if (BestCursor->kind == CXCursor_ObjCInterfaceDecl ||
+          BestCursor->kind == CXCursor_ObjCClassRef)
+        if (ObjCInterfaceDecl *PrevID
+             = dyn_cast_or_null<ObjCInterfaceDecl>(getCursorDecl(*BestCursor))){
+         if (PrevID != ID &&
+             !PrevID->isThisDeclarationADefinition() &&
+             !ID->isThisDeclarationADefinition())
+           return CXChildVisit_Break;
+        }
+    }
   }
 
   if (clang_isExpression(cursor.kind) &&
-- 
2.40.0