Added debug tests for indexing, pop_back and both forms of erase. Added an improved error message for erasing a single element with end().

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@177929 91177308-0d34-0410-b5e6-96231b3b80d8

test/containers/sequences/vector/db_index.pass.cpp

@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <vector>
+
+// Index vector out of bounds.
+
+#if _LIBCPP_DEBUG2 >= 1
+
+#define _LIBCPP_ASSERT(x, m) ((x) ? (void)0 : std::terminate())
+
+#include <vector>
+#include <cassert>
+#include <iterator>
+#include <exception>
+#include <cstdlib>
+
+void f1()
+{
+    std::exit(0);
+}
+
+int main()
+{
+    std::set_terminate(f1);
+    typedef int T;
+    typedef std::vector<T> C;
+    C c(1);
+    assert(c[0] == 0);
+    c.clear();
+    assert(c[0] == 0);
+    assert(false);
+}
+
+#else
+
+int main()
+{
+}
+
+#endif