1 files changed, 61 insertions, 0 deletions
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp
new file mode 100644
index 00000000000..768de568e22
--- /dev/null
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <regex>
+
+// template <class charT, class traits = regex_traits<charT>> class basic_regex;
+
+// template <class ST, class SA>
+//    basic_regex(const basic_string<charT, ST, SA>& s,
+//                flag_type f = regex_constants::ECMAScript);
+
+#include <regex>
+#include <cassert>
+
+template <class String>
+void
+test(const String& p, std::regex_constants::syntax_option_type f, unsigned mc)
+{
+    std::basic_regex<typename String::value_type> r(p, f);
+    assert(r.flags() == f);
+    assert(r.mark_count() == mc);
+}
+
+int main()
+{
+    test(std::string("\\(a\\)"), std::regex_constants::basic, 1);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::basic, 1);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::basic, 2);
+    test(std::string("(a([bc]))"), std::regex_constants::basic, 0);
+
+    test(std::string("\\(a\\)"), std::regex_constants::extended, 0);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::extended, 0);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::extended, 0);
+    test(std::string("(a([bc]))"), std::regex_constants::extended, 2);
+
+    test(std::string("\\(a\\)"), std::regex_constants::ECMAScript, 0);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::ECMAScript, 0);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::ECMAScript, 0);
+    test(std::string("(a([bc]))"), std::regex_constants::ECMAScript, 2);
+
+    test(std::string("\\(a\\)"), std::regex_constants::awk, 0);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::awk, 0);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::awk, 0);
+    test(std::string("(a([bc]))"), std::regex_constants::awk, 2);
+
+    test(std::string("\\(a\\)"), std::regex_constants::grep, 1);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::grep, 1);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::grep, 2);
+    test(std::string("(a([bc]))"), std::regex_constants::grep, 0);
+
+    test(std::string("\\(a\\)"), std::regex_constants::egrep, 0);
+    test(std::string("\\(a[bc]\\)"), std::regex_constants::egrep, 0);
+    test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::egrep, 0);
+    test(std::string("(a([bc]))"), std::regex_constants::egrep, 2);
+}