refactor: hex ascii view

Refactor hex ascii view.

sources/swarm/library/sources/json/placeholder_function.cpp

@@ -7,13 +7,15 @@
 #include <array>
 #include <cstdint>
 #include <cstring>
-#include <span>
 
 namespace swarm {
 
 class StringAppend {
  public:
-  explicit StringAppend(std::string& string) : string_{string}, pos_{0} {}
+  explicit StringAppend(size_t length, std::string& string)
+      : string_{string}, pos_{0} {
+    string_.resize(length, '\0');
+  }
 
   inline constexpr void Append(const char value) noexcept {
     string_[pos_++] = value;
@@ -29,6 +31,16 @@ class StringAppend {
     }
   }
 
+  using HexArray = const std::array<char, 16>;
+  static constexpr HexArray kHex = {'0', '1', '2', '3', '4', '5', '6', '7',
+                                    '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
+
+  inline void AppendAsHex(std::byte value) noexcept {
+    Append(kHex[static_cast<size_t>(value >> 4)]);
+    Append(kHex[static_cast<size_t>(value & std::byte{0x0f})]);
+    Append(' ');
+  }
+
   inline void FinalizeSize() noexcept { string_.resize(pos_, '\0'); }
 
  private:
@@ -37,18 +49,16 @@ class StringAppend {
 };
 
 inline void WriteLineNumber(size_t line_number,
-                            StringAppend& hex_vew) noexcept {
-  hex_vew.AppendDigit(line_number >> 12);
-  hex_vew.AppendDigit(line_number >> 8);
-  hex_vew.AppendDigit(line_number >> 4);
-  hex_vew.AppendDigit(line_number);
-  hex_vew.Append(':');
-  hex_vew.Append(' ');
+                            StringAppend& hex_view) noexcept {
+  hex_view.AppendDigit(line_number >> 12);
+  hex_view.AppendDigit(line_number >> 8);
+  hex_view.AppendDigit(line_number >> 4);
+  hex_view.AppendDigit(line_number);
+  hex_view.Append(':');
+  hex_view.Append(' ');
 }
 
-template <typename T>
-[[nodiscard]] inline constexpr std::span<const char> SpanFrom(
-    T& text) noexcept {
+[[nodiscard]] inline std::span<const char> SpanFrom(const char* text) noexcept {
   return std::span(text, strlen(text));
 }
 
@@ -64,25 +74,17 @@ inline void WriteSizeOfData(size_t size, StringAppend& hex_view) noexcept {
 
 void HexAsciiViewFrom(std::span<const std::byte> data,
                       std::string& hex_view) noexcept {
-  using HexArray = const std::array<char, 16>;
-  constexpr HexArray kHex = {'0', '1', '2', '3', '4', '5', '6', '7',
-                             '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
   const auto length = data.size();
-  hex_view.reserve(length * 5 + 20);
-  hex_view.resize(length * 5 + 20, '\0');
   const auto bytes_per_row = size_t{16};
   const auto rows = length / bytes_per_row;
-  StringAppend str{hex_view};
+  StringAppend str{length * 5 + 20, hex_view};
 
   for (size_t i = 0; i < rows; ++i) {
     const auto total_bytes = i * bytes_per_row;
     WriteLineNumber(total_bytes, str);
 
     for (size_t j = 0; j < bytes_per_row; ++j) {
-      const auto byte = data[total_bytes + j];
-      str.Append(kHex[static_cast<size_t>(byte >> 4)]);
-      str.Append(kHex[static_cast<size_t>(byte & std::byte{0x0f})]);
-      str.Append(' ');
+      str.AppendAsHex(data[total_bytes + j]);
     }
     str.Append(' ');
     for (size_t j = 0; j < bytes_per_row; ++j) {
@@ -101,21 +103,14 @@ void HexAsciiViewFrom(std::span<const std::byte> data,
 
   // Fill hex for last row values.
   for (size_t j = 0; j < rest_of_bytes; ++j) {
-    const auto byte = data[rows * bytes_per_row + j];
-    str.Append(kHex[static_cast<size_t>(byte >> 4)]);
-    str.Append(kHex[static_cast<size_t>(byte & std::byte{0x0f})]);
-    str.Append(' ');
+    str.AppendAsHex(data[rows * bytes_per_row + j]);
   }
 
   // Fill hex with spaces at last row if it is not full.
   for (size_t j = 0; j < bytes_per_row - rest_of_bytes; ++j) {
-    for (const char c : SpanFrom("   ")) {
-      str.Append(c);
-    }
+    str.Append(SpanFrom("   "));
   }
 
-  str.Append(' ');
-
   // Fill ascii last row values.
   for (size_t j = 0; j < rest_of_bytes; ++j) {
     const auto byte = data[rows * bytes_per_row + j];

sources/swarm/library/sources/json/placeholder_function.h

@@ -7,14 +7,10 @@
 
 #include <span>
 #include <string>
+#include <string_view>
 
 namespace swarm {
 
-template <typename T>
-[[nodiscard]] auto PlaceholderSumm(T a, T b) -> T {
-  return a + b;
-}
-
 void HexAsciiViewFrom(std::span<const std::byte> data,
                       std::string& hex_view) noexcept;
 

sources/swarm/library/sources/json/placeholder_function.h.autosave

@@ -0,0 +1,20 @@
+// SPDX-FileCopyrightText: © 2024 Melg Eight <[email protected]>
+//
+// SPDX-License-Identifier: MIT
+
+#ifndef PLACEHOLDER_FUNCTION_H
+#define PLACEHOLDER_FUNCTION_H
+
+#include <span>
+#include <string>
+
+namespace swarm {
+
+void HexAsciiViewFrom(std::span<const std::byte> data,
+                      std::string& hex_view) noexcept;
+
+auto HexAsciiViewFrom(std::span<const std::byte> data) noexcept -> std::string;
+
+}  // namespace swarm
+
+#endif  // PLACEHOLDER_FUNCTION_H

sources/swarm/tests/unit_tests/sources/placeholder.cpp

@@ -24,16 +24,13 @@ namespace swarm::test {
 }
 
 [[nodiscard]] inline std::string ExpectedOuput() noexcept {
-  std::string e{};
-  e.reserve(231);
-  e += "0000: 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f  "
-       "................\n";
-  e += "0010: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f  "
-       "................\n";
-  e += "0020: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e     "
-       " !\"#$%&'()*+,-. \n";
-  e += "Size: 47 bytes\n";
-  return e;
+  // clang-format off
+  return
+  "0000: 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f  ................\n"
+  "0010: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f  ................\n"
+  "0020: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e     !\"#$%&'()*+,-. \n"
+  "Size: 47 bytes\n";
+  // clang-format on
 }
 
 SCENARIO("placeholder") {