2 files changed, 31 insertions, 0 deletions
diff --git a/src/test-helper.cpp b/src/test-helper.cpp
index d441895..d591916 100644
--- a/src/test-helper.cpp
+++ b/src/test-helper.cpp
@@ -5,6 +5,8 @@
 #include <codecvt>
 #include <deque>
 #include <exception>
+#include <iostream>
+#include <iomanip>
 #include <limits>
 #include <list>
 #include <locale>
@@ -50,6 +52,29 @@ namespace std {
   return os;
  }
 
+#ifdef __cpp_char8_t
+ std::ostream& operator<<(std::ostream& os, utf8_t const& c)
+ {
+  os << "\\x" << std::setfill('0') << std::setw(2) << std::right << std::hex << static_cast<uint8_t>(c);
+
+  return os;
+ }
+#endif
+
+ std::ostream& operator<<(std::ostream& os, char16_t const& c)
+ {
+  os << "\\u" << std::setfill('0') << std::setw(4) << std::right << std::hex << static_cast<uint16_t>(c);
+
+  return os;
+ }
+
+ std::ostream& operator<<(std::ostream& os, char32_t const& c)
+ {
+  os << "\\U" << std::setfill('0') << std::setw(8) << std::right << std::hex << static_cast<uint32_t>(c);
+
+  return os;
+ }
+
 } // namespace std
 
 namespace {
diff --git a/src/test-helper.h b/src/test-helper.h
index c3e2900..676af73 100644
--- a/src/test-helper.h
+++ b/src/test-helper.h
@@ -14,6 +14,12 @@ namespace std {
  std::ostream& operator<<(std::ostream& os, std::basic_string<char16_t> const& s);
  std::ostream& operator<<(std::ostream& os, std::basic_string<char32_t> const& s);
 
+#ifdef __cpp_char8_t
+ std::ostream& operator<<(std::ostream& os, utf8_t const& c);
+#endif
+ std::ostream& operator<<(std::ostream& os, char16_t const& c);
+ std::ostream& operator<<(std::ostream& os, char32_t const& c);
+
 } // namespace std
 
 template<typename From, typename To>