feat: add termcolor in carton.

- add termcolor and its testbench
- add integer() in flag_enum and update its testbench according to the requirements in termcolor.

testbench/yycc/carton/termcolor.cpp

@@ -0,0 +1,44 @@
+#include <gtest/gtest.h>
+#include <yycc.hpp>
+#include <yycc/carton/termcolor.hpp>
+#include <yycc/flag_enum.hpp>
+
+#define TERMCOLOR ::yycc::carton::termcolor
+#define FLAG_ENUM ::yycc::flag_enum
+
+using namespace std::literals::string_view_literals;
+using Color = TERMCOLOR::Color;
+using Attribute = TERMCOLOR::Attribute;
+
+namespace yycctest::carton::termcolor {
+
+    TEST(CartonTermcolor, Lowlevel) {
+        EXPECT_EQ(TERMCOLOR::foreground(Color::Default), u8"");
+        EXPECT_EQ(TERMCOLOR::foreground(Color::Red), u8"\033[31m");
+        EXPECT_EQ(TERMCOLOR::foreground(Color::LightRed), u8"\033[91m");
+
+        EXPECT_EQ(TERMCOLOR::background(Color::Default), u8"");
+        EXPECT_EQ(TERMCOLOR::background(Color::Red), u8"\033[41m");
+        EXPECT_EQ(TERMCOLOR::background(Color::LightRed), u8"\033[101m");
+
+        EXPECT_EQ(TERMCOLOR::style(Attribute::Default), u8"");
+        EXPECT_EQ(TERMCOLOR::style(Attribute::Italic), u8"\033[3m");
+        EXPECT_EQ(TERMCOLOR::styles(FLAG_ENUM::merge(Attribute::Italic, Attribute::Bold)),
+                  u8"\033[1m"
+                  "\033[3m");
+
+        EXPECT_EQ(TERMCOLOR::reset(), u8"\033[0m"sv);
+    }
+
+    TEST(CartonTermcolor, Highlevel) {
+        EXPECT_EQ(TERMCOLOR::colored(u8"hello"sv), u8"hello\033[0m");
+        EXPECT_EQ(TERMCOLOR::colored(u8"hello"sv, Color::LightWhite, Color::Red, FLAG_ENUM::merge(Attribute::Italic, Attribute::Bold)),
+                  u8"\033[97m"
+                  "\033[41m"
+                  "\033[1m"
+                  "\033[3m"
+                  "hello"
+                  "\033[0m");
+    }
+
+} // namespace yycctest::carton::termcolor

testbench/yycc/flag_enum.cpp

@@ -1,6 +1,7 @@
 #include <gtest/gtest.h>
 #include <yycc.hpp>
 #include <yycc/flag_enum.hpp>
+#include <cinttypes>
 
 #include <yycc/rust/prelude.hpp>
 
@@ -74,4 +75,9 @@ namespace yycctest::flag_enum {
         EXPECT_TRUE(FLAG_ENUM::boolean(TestEnum::MergedBit247));
     }
 
+    TEST(FlagEnum, Integer) {
+        EXPECT_EQ(FLAG_ENUM::integer(TestEnum::Empty), UINT8_C(0));
+        EXPECT_EQ(FLAG_ENUM::integer(TestEnum::Bit1), UINT8_C(1));
+    }
+
 }