Function CreateCodePointFromUtf16SurrogatePair

tests/gtest/gtest-all.cc:3291–3302

Creates a Unicode code point from UTF16 surrogate pair.

// Creates a Unicode code point from UTF16 surrogate pair.
inline UInt32 CreateCodePointFromUtf16SurrogatePair(wchar_t first,
                                                    wchar_t second) {
  const auto first_u = static_cast<UInt32>(first);
  const auto second_u = static_cast<UInt32>(second);
  const UInt32 mask = (1 << 10) - 1;
  return (sizeof(wchar_t) == 2)
             ? (((first_u & mask) << 10) | (second_u & mask)) + 0x10000
             :
             // This function should not be called when the condition is
             // false, but we provide a sensible default in case it is.
             first_u;
}

// Converts a wide string to a narrow string in UTF-8 encoding.
// The wide string is assumed to have the following encoding: