1 files changed, 81 insertions, 0 deletions

diff --git a/libcxx/test/strings/basic.string/string.capacity/reserve.pass.cpp b/libcxx/test/strings/basic.string/string.capacity/reserve.pass.cpp
new file mode 100644
index 00000000000..92d91237639
--- /dev/null
+++ b/libcxx/test/strings/basic.string/string.capacity/reserve.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// ΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚΚThe LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <string>
+
+// void reserve(size_type res_arg=0);
+
+#include <string>
+#include <stdexcept>
+#include <cassert>
+
+template <class S>
+void
+test(S s)
+{
+    typename S::size_type old_cap = s.capacity();
+    S s0 = s;
+    s.reserve();
+    assert(s.__invariants());
+    assert(s == s0);
+    assert(s.capacity() <= old_cap);
+    assert(s.capacity() >= s.size());
+}
+
+template <class S>
+void
+test(S s, typename S::size_type res_arg)
+{
+    typename S::size_type old_cap = s.capacity();
+    S s0 = s;
+    try
+    {
+        s.reserve(res_arg);
+        assert(res_arg <= s.max_size());
+        assert(s == s0);
+        assert(s.capacity() >= res_arg);
+        assert(s.capacity() >= s.size());
+    }
+    catch (std::length_error&)
+    {
+        assert(res_arg > s.max_size());
+    }
+}
+
+int main()
+{
+    typedef std::string S;
+    {
+    S s;
+    test(s);
+
+    s.assign(10, 'a');
+    s.erase(5);
+    test(s);
+
+    s.assign(100, 'a');
+    s.erase(50);
+    test(s);
+    }
+    {
+    S s;
+    test(s, 5);
+    test(s, 10);
+    test(s, 50);
+    }
+    {
+    S s(100, 'a');
+    s.erase(50);
+    test(s, 5);
+    test(s, 10);
+    test(s, 50);
+    test(s, 100);
+    test(s, S::npos);
+    }
+}