[cling] Add test for autocomplete functionality

Author: devajithvs

interpreter/cling/test/AutoComplete/AutoComplete.C

@@ -0,0 +1,31 @@
+//------------------------------------------------------------------------------
+// CLING - the C++ LLVM-based InterpreterG :)
+//
+// This file is dual-licensed: you can choose to license it under the University
+// of Illinois Open Source License or the GNU Lesser General Public License. See
+// LICENSE.TXT for details.
+//------------------------------------------------------------------------------
+
+// RUN: cat %s | %cling 2>&1 | FileCheck %s
+
+// Test to check autocomplete functionality (adapted from CppInterOp)
+
+#include "cling/Interpreter/Interpreter.h"
+
+gCling->process("int foo = 12;");
+std::vector<std::string> cc;
+size_t cursor = 1;
+gCling->codeComplete("f", cursor, cc);
+
+// We check only for 'float' and 'foo', because they
+// must be present in the result. Other hints may appear
+// there, depending on the implementation, but these two
+// are required to say that the test is working.
+size_t cnt = 0;
+for (auto& r : cc) {
+  if (r == "float" || r == "[#int#]foo") cnt++;
+}
+
+cnt
+// CHECK: (unsigned long) 2
+.q