Enum CharFormat

tests/gtest/gtest-all.cc:11231–11235

Depending on the value of a char (or wchar_t), we print it in one of three formats: - as is if it's a printable ASCII (e.g. 'a', '2', ' '), - as a hexadecimal escape sequence (e.g. '\x7F'), or - as a special escape sequence (e.g. '\r', '\n').

//   - as a hexadecimal escape sequence (e.g. '\x7F'), or
//   - as a special escape sequence (e.g. '\r', '\n').
enum CharFormat {
  kAsIs,
  kHexEscape,
  kSpecialEscape
};

// Returns true if c is a printable ASCII character.  We test the
// value of c directly instead of calling isprint(), which is buggy on