missed hex .hpp + test .cpp in prev commit

compression/include/compression/hex.hpp

@@ -0,0 +1,60 @@
+// hex.hpp
+
+#pragma once
+
+#include <iostream>
+
+struct hex {
+    hex(std::uint8_t x, bool w_char = false) : x_{x}, with_char_{w_char} {}
+
+    std::uint8_t x_;
+    bool with_char_;
+};
+
+struct hex_view {
+    hex_view(std::uint8_t const * lo, std::uint8_t const * hi, bool as_text) : lo_{lo}, hi_{hi}, as_text_{as_text} {}
+    hex_view(char const * lo, char const * hi, bool as_text)
+        : lo_{reinterpret_cast<std::uint8_t const *>(lo)},
+          hi_{reinterpret_cast<std::uint8_t const *>(hi)},
+          as_text_{as_text} {}
+
+    std::uint8_t const * lo_;
+    std::uint8_t const * hi_;
+    bool as_text_;
+};
+
+inline std::ostream &
+operator<< (std::ostream & os, hex const & ins) {
+    std::uint8_t lo = ins.x_ & 0xf;
+    std::uint8_t hi = ins.x_ >> 4;
+
+    char lo_ch = (lo < 10) ? '0' + lo : 'a' + lo - 10;
+    char hi_ch = (hi < 10) ? '0' + hi : 'a' + hi - 10;
+
+    os << hi_ch << lo_ch;
+
+    if (ins.with_char_) {
+        os << "(";
+        if (std::isprint(ins.x_))
+            os << static_cast<char>(ins.x_);
+        else
+            os << "?";
+        os << ")";
+    }
+
+    return os;
+}
+
+inline std::ostream &
+operator<< (std::ostream & os, hex_view const & ins) {
+    os << "[";
+    std::size_t i = 0;
+    for (std::uint8_t const * p = ins.lo_; p < ins.hi_; ++p) {
+        if (i > 0)
+            os << " ";
+        os << hex(*p, ins.as_text_);
+        ++i;
+    }
+    os << "]";
+    return os;
+}

compression/utest/hex.test.cpp

@@ -0,0 +1,35 @@
+#define CATCH_CONFIG_ENABLE_BENCHMARKING
+
+#include "compression/hex.hpp"
+#include <catch2/catch.hpp>
+#include <sstream>
+
+using namespace std;
+
+TEST_CASE("hex", "[hex]") {
+    stringstream ss;
+
+    ss << ::hex(15, false);
+
+    REQUIRE(ss.str() == "0f");
+}
+
+TEST_CASE("hex_view", "[hex]") {
+    stringstream ss;
+
+    array<uint8_t, 3> v = {{ 10, 20, 30 }};
+
+    ss << ::hex_view(&v[0], &v[v.size()], false);
+
+    REQUIRE(ss.str() == "[0a 14 1e]");
+}
+
+TEST_CASE("hex_view_2", "[hex]") {
+    stringstream ss;
+
+    array<uint8_t, 3> v = {{ 'a', 'm', 'z' }};
+
+    ss << ::hex_view(&v[0], &v[v.size()], true);
+
+    REQUIRE(ss.str() == "[61(a) 6d(m) 7a(z)]");
+}