[lldb] Test direct ivar access in objc++ (NFC)

Add an Objective-C++ specific test for direct ivar access. This adds to the existing C++ and ObjC tests, and tests against regression for future refactoring.

Differential Revision: https://reviews.llvm.org/D146320

lldb/test/API/commands/frame/var/direct-ivar/objcpp/Makefile

@@ -0,0 +1,4 @@
+OBJCXX_SOURCES := main.mm
+CFLAGS_EXTRAS := -fblocks -fobjc-arc
+LD_EXTRAS := -lobjc
+include Makefile.rules

lldb/test/API/commands/frame/var/direct-ivar/objcpp/TestFrameVarDirectIvarObjCPlusPlus.py

@@ -0,0 +1,24 @@
+import lldb
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test.decorators import *
+from lldbsuite.test import lldbutil
+
+
+class TestCase(TestBase):
+    @skipUnlessDarwin
+    def test_objc_self(self):
+        self.build()
+        lldbutil.run_to_source_breakpoint(self, "check self", lldb.SBFileSpec("main.mm"))
+        self.expect("frame variable _ivar", startstr="(int) _ivar = 30")
+
+    @skipUnlessDarwin
+    def test_objc_explicit_self(self):
+        self.build()
+        lldbutil.run_to_source_breakpoint(self, "check explicit self", lldb.SBFileSpec("main.mm"))
+        self.expect("frame variable _ivar", startstr="(int) _ivar = 30")
+
+    @skipUnlessDarwin
+    def test_cpp_this(self):
+        self.build()
+        lldbutil.run_to_source_breakpoint(self, "check this", lldb.SBFileSpec("main.mm"))
+        self.expect("frame variable m_field", startstr="(int) m_field = 41")

lldb/test/API/commands/frame/var/direct-ivar/objcpp/main.mm

@@ -0,0 +1,35 @@
+#import <objc/NSObject.h>
+#include <stdio.h>
+
+struct Structure {
+  int m_field;
+  void fun() {
+    puts("check this\n");
+  }
+};
+
+@interface Classic : NSObject {
+@public
+  int _ivar;
+}
+@end
+
+@implementation Classic
+- (void)fun {
+  puts("check self\n");
+}
+@end
+
+int main() {
+  Structure s;
+  s.m_field = 41;
+  s.fun();
+
+  Classic *c = [Classic new];
+  c->_ivar = 30;
+  [c fun];
+
+  Classic *self = c;
+  puts("check explicit self\n");
+  (void)self;
+}