From 60e3d6305d1e618d84661a39a1285cecaf847304 Mon Sep 17 00:00:00 2001
From: Alfi Maulana <alfi.maulana.f@gmail.com>
Date: Wed, 21 Jun 2023 14:46:30 +0700
Subject: [PATCH] feat(error): add `Error` struct

---
 error/CMakeLists.txt              |  5 +++--
 error/include/error/error.hpp     | 18 ++++++++++++++++++
 error/include/example/example.hpp |  7 -------
 error/src/error.cpp               |  7 +++++++
 error/src/example.cpp             |  7 -------
 error/test/error_test.cpp         |  8 ++++++++
 error/test/example_test.cpp       |  7 -------
 7 files changed, 36 insertions(+), 23 deletions(-)
 create mode 100644 error/include/error/error.hpp
 delete mode 100644 error/include/example/example.hpp
 create mode 100644 error/src/error.cpp
 delete mode 100644 error/src/example.cpp
 create mode 100644 error/test/error_test.cpp
 delete mode 100644 error/test/example_test.cpp

diff --git a/error/CMakeLists.txt b/error/CMakeLists.txt
index 0cf8e9d..2d604e1 100644
--- a/error/CMakeLists.txt
+++ b/error/CMakeLists.txt
@@ -3,8 +3,9 @@ cmake_minimum_required(VERSION 3.0)
 project(error)
 
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -Wshadow -Wnon-virtual-dtor -Wpedantic")
+set(CMAKE_CXX_STANDARD 11)
 
-add_library(error src/example.cpp)
+add_library(error src/error.cpp)
 target_include_directories(error PUBLIC include)
 
 if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
@@ -19,7 +20,7 @@ if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
 
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fprofile-arcs -ftest-coverage -fPIC -O0")
 
-    add_executable(error_test test/example_test.cpp)
+    add_executable(error_test test/error_test.cpp)
     target_link_libraries(error_test PRIVATE error Catch2::Catch2WithMain)
     catch_discover_tests(error_test)
   endif()
diff --git a/error/include/error/error.hpp b/error/include/error/error.hpp
new file mode 100644
index 0000000..0391eab
--- /dev/null
+++ b/error/include/error/error.hpp
@@ -0,0 +1,18 @@
+#pragma once
+
+#include <exception>
+
+namespace error {
+
+/**
+ * @brief A struct that represents error information.
+ */
+struct Error : public std::exception {
+  /**
+   * @brief Returns the explanatory string.
+   * @return Pointer to a null-terminated string with explanatory information.
+   */
+  const char* what() const noexcept override;
+};
+
+}  // namespace error
diff --git a/error/include/example/example.hpp b/error/include/example/example.hpp
deleted file mode 100644
index 1d53053..0000000
--- a/error/include/example/example.hpp
+++ /dev/null
@@ -1,7 +0,0 @@
-#pragma once
-
-namespace example {
-
-bool is_odd(int val);
-
-}  // namespace example
diff --git a/error/src/error.cpp b/error/src/error.cpp
new file mode 100644
index 0000000..9020e7a
--- /dev/null
+++ b/error/src/error.cpp
@@ -0,0 +1,7 @@
+#include <error/error.hpp>
+
+namespace error {
+
+const char* Error::what() const noexcept { return "unknown error"; }
+
+}  // namespace error
diff --git a/error/src/example.cpp b/error/src/example.cpp
deleted file mode 100644
index bed773d..0000000
--- a/error/src/example.cpp
+++ /dev/null
@@ -1,7 +0,0 @@
-#include <example/example.hpp>
-
-namespace example {
-
-bool is_odd(int val) { return val % 2 == 1; }
-
-}  // namespace example
diff --git a/error/test/error_test.cpp b/error/test/error_test.cpp
new file mode 100644
index 0000000..f96f4e8
--- /dev/null
+++ b/error/test/error_test.cpp
@@ -0,0 +1,8 @@
+#include <catch2/catch_test_macros.hpp>
+#include <error/error.hpp>
+
+TEST_CASE("test Error::what") {
+  const error::Error err;
+  const std::string expected("unknown error");
+  REQUIRE(expected.compare(err.what()) == 0);
+}
diff --git a/error/test/example_test.cpp b/error/test/example_test.cpp
deleted file mode 100644
index f8a5f4a..0000000
--- a/error/test/example_test.cpp
+++ /dev/null
@@ -1,7 +0,0 @@
-#include <catch2/catch_test_macros.hpp>
-#include <example/example.hpp>
-
-TEST_CASE("test is odd") {
-  CHECK(example::is_odd(3));
-  CHECK_FALSE(example::is_odd(4));
-}