Move DebugChar into its own file

Change-Id: Ia40549e5d0b78ece8dd0722c3a5a032b9915f24b

tests/unit/libutil-support/tests/cli-literate-parser.cc

@@ -1,6 +1,6 @@
 #include "cli-literate-parser.hh"
 #include "libexpr/print.hh"
-#include "debug-char.hh"
+#include "escape-char.hh"
 #include "types.hh"
 #include "util.hh"
 #include <ranges>
@@ -77,7 +77,7 @@ CLILiterateParser::CLILiterateParser(std::string prompt, size_t indent)
 void CLILiterateParser::feed(char c)
 {
     if constexpr (DEBUG_PARSER) {
-        std::cout << stateDebug(state_) << " " << DebugChar{c} << "\n";
+        std::cout << stateDebug(state_) << " " << MaybeHexEscapedChar{c} << "\n";
     }
 
     if (c == '\n') {

tests/unit/libutil-support/tests/debug-char.hh

@@ -1,24 +0,0 @@
-///@file
-#include <ostream>
-#include <boost/io/ios_state.hpp>
-
-namespace nix {
-
-struct DebugChar
-{
-    char c;
-};
-
-inline std::ostream & operator<<(std::ostream & s, DebugChar c)
-{
-    boost::io::ios_flags_saver _ifs(s);
-
-    if (isprint(c.c)) {
-        s << static_cast<char>(c.c);
-    } else {
-        s << std::hex << "0x" << (static_cast<unsigned int>(c.c) & 0xff);
-    }
-    return s;
-}
-
-}

tests/unit/libutil-support/tests/terminal-code-eater.cc

@@ -1,5 +1,5 @@
 #include "terminal-code-eater.hh"
-#include "debug-char.hh"
+#include "escape-char.hh"
 #include <assert.h>
 #include <cstdint>
 #include <iostream>
@@ -14,7 +14,7 @@ void TerminalCodeEater::feed(char c, std::function<void(char)> on_char)
     auto isIntermediateChar = [](char v) -> bool { return v >= 0x20 && v <= 0x2f; };
     auto isFinalChar = [](char v) -> bool { return v >= 0x40 && v <= 0x7e; };
     if constexpr (DEBUG_EATER) {
-        std::cerr << "eater" << DebugChar{c} << "\n";
+        std::cerr << "eater" << MaybeHexEscapedChar{c} << "\n";
     }
 
     switch (state) {
@@ -28,7 +28,7 @@ void TerminalCodeEater::feed(char c, std::function<void(char)> on_char)
             return;
         }
         if constexpr (DEBUG_EATER) {
-            std::cerr << "eater uneat" << DebugChar{c} << "\n";
+            std::cerr << "eater uneat" << MaybeHexEscapedChar{c} << "\n";
         }
         on_char(c);
         break;