Start adding integration tests

Author: monkeyman192

.github/workflows/pipeline.yml

@@ -13,7 +13,7 @@ on:
 jobs:
   lint_testing:
     name: Lint and test code
-    runs-on: Windows-latest
+    runs-on: Windows-2025
     strategy:
       matrix:
         py_ver: [
@@ -39,11 +39,23 @@ jobs:
         run: |
           uv run ruff check ./pymhf ./tests
           uv run ruff format --check ./pymhf ./tests
+      - name: Install compiler
+        id: install_gpp
+        uses: rlalik/setup-cpp-compiler@master
+        with:
+          compiler: g++-14.2.0
+      - name: Build test binaries
+        run: g++ ./tests/cpp/app.cpp -Wall -o ./tests/app.exe
+      - name: Upload exe
+        uses: actions/upload-artifact@v4
+        with:
+          name: test_app
+          path: ./tests/app.exe
       - name: Run unit tests
         run: uv run pytest ./tests
   build:
     name: Build wheel and docs
-    runs-on: Windows-latest
+    runs-on: Windows-2025
     needs:
       - lint_testing
     steps:

tests/cpp/app.cpp

@@ -0,0 +1,19 @@
+#include <iostream>
+#include <cstdint>
+
+using namespace std;
+
+extern "C" __declspec( dllexport ) int64_t multiply(long a, int64_t b) {
+    return a * b;
+}
+
+int main() {
+    int64_t a;
+    int64_t b;
+    cout << "Enter a number: ";
+    cin >> a;
+    cout << "Enter another number: ";
+    cin >> b;
+    cout << "The product is " << multiply(a, b) << endl;
+    return 0;
+}