_

Author: Zind

CMakeLists.txt

@@ -1,8 +1,33 @@
-cmake_minimum_required(VERSION 3.16)
-project(hello_cpp_codespace VERSION 0.1.0 LANGUAGES CXX)
+cmake_minimum_required(VERSION 3.22)
+project(hello_cpp_codespace LANGUAGES CXX)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
 
-add_executable(hello src/main.cpp)
+# Warnings for GCC/Clang
+if (CMAKE_CXX_COMPILER_ID MATCHES "Clang|GNU")
+  add_compile_options(-Wall -Wextra -Wpedantic -Wconversion -Wsign-conversion)
+endif()
+
+# Library (example)
+add_library(mylib src/lib.cpp)
+target_include_directories(mylib PUBLIC include)
+
+# Tests with Catch2 (via FetchContent)
+include(FetchContent)
+FetchContent_Declare(
+  Catch2
+  GIT_REPOSITORY https://github.com/catchorg/Catch2.git
+  GIT_TAG v3.5.4
+)
+FetchContent_MakeAvailable(Catch2)
+
+add_executable(tests
+  tests/test_sum.cpp
+  tests/test_ring_buffer.cpp
+)
+target_link_libraries(tests PRIVATE mylib Catch2::Catch2WithMain)
+include(CTest)
+include(Catch)
+catch_discover_tests(tests)

CMakePresets_Version2.json

@@ -0,0 +1,24 @@
+{
+  "version": 5,
+  "cmakeMinimumRequired": { "major": 3, "minor": 22 },
+  "configurePresets": [
+    {
+      "name": "dev-debug",
+      "displayName": "Dev Debug",
+      "generator": "Ninja",
+      "binaryDir": "build",
+      "cacheVariables": {
+        "CMAKE_BUILD_TYPE": "Debug",
+        "CMAKE_CXX_STANDARD": "17",
+        "CMAKE_CXX_STANDARD_REQUIRED": "ON",
+        "CMAKE_EXPORT_COMPILE_COMMANDS": "ON"
+      }
+    }
+  ],
+  "buildPresets": [
+    { "name": "dev", "configurePreset": "dev-debug" }
+  ],
+  "testPresets": [
+    { "name": "dev", "configurePreset": "dev-debug", "output": { "outputOnFailure": true } }
+  ]
+}

include/lib.hpp

@@ -0,0 +1,4 @@
+#pragma once
+#include <vector>
+
+int sum(const std::vector<int>& v);

include/ring_buffer.hpp

@@ -0,0 +1,49 @@
+#pragma once
+#include <array>
+#include <cstddef>
+#include <optional>
+#include <utility>
+
+template <typename T, std::size_t N>
+class RingBuffer {
+    static_assert(N > 0, "N must be > 0");
+public:
+    RingBuffer() = default;
+
+    bool push(const T& v) {
+        if (full()) return false;
+        buf_[head_] = v;
+        head_ = (head_ + 1) % N;
+        ++count_;
+        return true;
+    }
+    bool push(T&& v) {
+        if (full()) return false;
+        buf_[head_] = std::move(v);
+        head_ = (head_ + 1) % N;
+        ++count_;
+        return true;
+    }
+    std::optional<T> pop() {
+        if (empty()) return std::nullopt;
+        T out = std::move(buf_[tail_]);
+        tail_ = (tail_ + 1) % N;
+        --count_;
+        return out;
+    }
+    const T* peek() const {
+        if (empty()) return nullptr;
+        return &buf_[tail_];
+    }
+
+    bool empty() const noexcept { return count_ == 0; }
+    bool full()  const noexcept { return count_ == N; }
+    std::size_t size() const noexcept { return count_; }
+    std::size_t capacity() const noexcept { return N; }
+
+private:
+    std::array<T, N> buf_{};
+    std::size_t head_ = 0;  // next write
+    std::size_t tail_ = 0;  // next read
+    std::size_t count_ = 0; // items in buffer
+};

src/libb.cpp

@@ -0,0 +1,7 @@
+#include "lib.hpp"
+
+int sum(const std::vector<int>& v) {
+    int s = 0;
+    for (int x : v) s += x;
+    return s;
+}

tests/test_ring_buffer.cpp

@@ -0,0 +1,33 @@
+#include <catch2/catch_test_macros.hpp>
+#include "ring_buffer.hpp"
+#include <string>
+
+TEST_CASE("RingBuffer basic push/pop") {
+    RingBuffer<int, 3> rb;
+    REQUIRE(rb.empty());
+    REQUIRE(rb.push(1));
+    REQUIRE(rb.push(2));
+    REQUIRE(rb.push(3));
+    REQUIRE(rb.full());
+    REQUIRE_FALSE(rb.push(4));
+
+    auto a = rb.pop(); REQUIRE(a && *a == 1);
+    auto b = rb.pop(); REQUIRE(b && *b == 2);
+    auto c = rb.pop(); REQUIRE(c && *c == 3);
+    REQUIRE(rb.empty());
+    REQUIRE_FALSE(rb.pop().has_value());
+}
+
+TEST_CASE("RingBuffer wraparound and peek") {
+    RingBuffer<std::string, 2> rb;
+    REQUIRE(rb.push("A"));
+    REQUIRE(rb.push("B"));
+    REQUIRE(rb.full());
+    REQUIRE(std::string(*rb.peek()) == "A");
+    REQUIRE(rb.pop().value() == "A");
+    REQUIRE(rb.push("C"));
+    REQUIRE(rb.full());
+    REQUIRE(rb.pop().value() == "B");
+    REQUIRE(rb.pop().value() == "C");
+    REQUIRE(rb.empty());
+}

tests/test_sum.cpp

@@ -0,0 +1,8 @@
+#include <catch2/catch_test_macros.hpp>
+#include "lib.hpp"
+
+TEST_CASE("sum works") {
+    REQUIRE(sum({}) == 0);
+    REQUIRE(sum({1}) == 1);
+    REQUIRE(sum({1,2,3}) == 6);
+}