Format (un)signed char as integer by default (#217)

format.h

@@ -1045,8 +1045,8 @@ class MakeValue : public Arg {
   FMT_MAKE_VALUE(float, double_value, DOUBLE)
   FMT_MAKE_VALUE(double, double_value, DOUBLE)
   FMT_MAKE_VALUE(long double, long_double_value, LONG_DOUBLE)
-  FMT_MAKE_VALUE(signed char, int_value, CHAR)
-  FMT_MAKE_VALUE(unsigned char, int_value, CHAR)
+  FMT_MAKE_VALUE(signed char, int_value, INT)
+  FMT_MAKE_VALUE(unsigned char, int_value, UINT)
   FMT_MAKE_VALUE(char, int_value, CHAR)
 
 #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)

test/format-test.cc

@@ -1324,6 +1324,11 @@ TEST(FormatterTest, FormatChar) {
   EXPECT_EQ(fmt::format("{:02X}", n), fmt::format("{:02X}", 'x'));
 }
 
+TEST(FormatterTest, FormatUnsignedChar) {
+  EXPECT_EQ("42", format("{}", static_cast<unsigned char>(42)));
+  EXPECT_EQ("42", format("{}", static_cast<uint8_t>(42)));
+}
+
 TEST(FormatterTest, FormatWChar) {
   EXPECT_EQ(L"a", format(L"{0}", L'a'));
   // This shouldn't compile:

test/util-test.cc

@@ -471,11 +471,6 @@ TEST(ArgTest, MakeArg) {
   EXPECT_ARG_(wchar_t, BOOL, bool, int, true);
 
   // Test char.
-  EXPECT_ARG(CHAR, signed char, 'a');
-  EXPECT_ARG(CHAR, signed char, SCHAR_MIN);
-  EXPECT_ARG(CHAR, signed char, SCHAR_MAX);
-  EXPECT_ARG(CHAR, unsigned char, 'a');
-  EXPECT_ARG(CHAR, unsigned char, UCHAR_MAX );
   EXPECT_ARG(CHAR, char, 'a');
   EXPECT_ARG(CHAR, char, CHAR_MIN);
   EXPECT_ARG(CHAR, char, CHAR_MAX);
@@ -485,6 +480,13 @@ TEST(ArgTest, MakeArg) {
   EXPECT_ARGW(CHAR, wchar_t, WCHAR_MIN);
   EXPECT_ARGW(CHAR, wchar_t, WCHAR_MAX);
 
+  // Test signed/unsigned char.
+  EXPECT_ARG(INT, signed char, 42);
+  EXPECT_ARG(INT, signed char, SCHAR_MIN);
+  EXPECT_ARG(INT, signed char, SCHAR_MAX);
+  EXPECT_ARG(UINT, unsigned char, 42);
+  EXPECT_ARG(UINT, unsigned char, UCHAR_MAX );
+
   // Test short.
   EXPECT_ARG(INT, short, 42);
   EXPECT_ARG(INT, short, SHRT_MIN);