Add pure C++ unit tests using Google Test

[Copilot]

Existing tests are C#-only and test C++ functionality indirectly through interop. This adds direct C++ unit tests for OSPSuite.SimModelNative.

Changes

Test Infrastructure

• New project: tests/OSPSuite.SimModelNative.Tests using Google Test v1.14.0
• CMakeLists.txt: Unix build with FetchContent for gtest, links against SimModelNative sources
• vcxproj: Windows build with NuGet gtest package, explicit source file listings
• Solution integration: Added to Tests folder in OSPSuite.SimModel.sln

Build Integration

• buildWindows.bat: Builds test executable, runs with XML output
• buildNix.sh: CMake build for Linux/macOS, executes tests post-build

Test Coverage (200+ assertions)

• MathHelper: NaN/Inf/finite checks, IsNumeric, Pi, distributions
• ConstantFormula: Construction, value ops, IsZero, Clone, DE_Jacobian
• ValuePoint: Constructors, copy semantics, field validation
• TObjectVector: push_back, clear, indexing, memory management
• Formula classes: MinFormula, MaxFormula, DivFormula, DiffFormula constructors

Example

TEST_F(MathHelperTest, NormalDistribution) {
    // Test normal distribution at mean
    double result = MathHelper::NormalDistribution(0.0, 1.0, 0.0);
    EXPECT_NEAR(result, 1.0 / std::sqrt(2.0 * MathHelper::Pi()), 1e-10);
    
    // Verify symmetry
    EXPECT_NEAR(
        MathHelper::NormalDistribution(0.0, 1.0, 1.0),
        MathHelper::NormalDistribution(0.0, 1.0, -1.0),
        1e-10
    );
}

Tests run on Windows (x64), Ubuntu (x64/ARM64), and macOS (x64/ARM64) in CI pipeline with XML output artifacts.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Add pure C++ tests</issue_title>
<issue_description>The tests in the project https://github.com/Yuri05/OSPSuite.SimModel/tree/master/tests/OSPSuite.SimModel.Tests are all written in C# and test the C++ functionality (encapsulated in the project https://github.com/Yuri05/OSPSuite.SimModel/tree/master/src/OSPSuite.SimModelNative ) only indirectly.

Add the second test project which tests the C++ functionality directly (without relying on C#).

• Select appropriate testing framework which will run under Windows, Ubuntu, and MacOS
• Add new project (tests/OSPSuite.SimModelNative.Tests)
  • This project should be added to the Visual Studio solution https://github.com/Yuri05/OSPSuite.SimModel/blob/master/OSPSuite.SimModel.sln (and located within the solution under the existing Folder "Tests")
• Make sure the new test project is properly handled
  • Under Windows:

    OSPSuite.SimModel/buildWindows.bat

    Line 4 in 97b52a1

    dotnet test tests/OSPSuite.SimModel.Tests/OSPSuite.SimModel.Tests.csproj --no-build --no-restore --configuration:Release --verbosity normal --logger:"html;LogFileName=../../../testLog_Windows.html"

  • Under Linux (Ubuntu)/MacOS:

    OSPSuite.SimModel/buildNix.sh

    Line 52 in 97b52a1

    dotnet test tests/OSPSuite.SimModel.Tests/OSPSuite.SimModel.Tests.csproj --no-build --no-restore --configuration:Release --verbosity normal --logger:"html;LogFileName=../../../testLog_$1.html"

• Add unit tests to the newly created project to cover the source code in https://github.com/Yuri05/OSPSuite.SimModel/tree/master/src/OSPSuite.SimModelNative as much as possible)</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add pure C++ tests #3

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[Copilot]

Pull Request Overview

This PR adds direct C++ unit testing infrastructure to the OSPSuite.SimModel project using Google Test framework v1.14.0. It introduces a new test project (OSPSuite.SimModelNative.Tests) that tests C++ functionality directly without C# interop, complementing the existing C# tests.

Key changes:

• New cross-platform test project with Google Test integration (NuGet for Windows, FetchContent for Unix)
• Build script integration for automated test execution with XML output generation
• Initial test coverage for core utilities (MathHelper, ConstantFormula), data structures (ValuePoint, TObjectVector), and formula classes

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/OSPSuite.SimModelNative.Tests/CMakeLists.txt	CMake configuration for Unix builds with Google Test integration via FetchContent
tests/OSPSuite.SimModelNative.Tests/OSPSuite.SimModelNative.Tests.vcxproj	Visual Studio project file for Windows builds with NuGet-based Google Test dependency
tests/OSPSuite.SimModelNative.Tests/OSPSuite.SimModelNative.Tests.vcxproj.filters	Project filters organizing test and source files
tests/OSPSuite.SimModelNative.Tests/packages.config	NuGet package configuration specifying googletest 1.14.0
tests/OSPSuite.SimModelNative.Tests/README.md	Comprehensive documentation for building, running, and extending tests
tests/OSPSuite.SimModelNative.Tests/src/MathHelperTests.cpp	Unit tests for MathHelper utilities and ConstantFormula with main() entry point
tests/OSPSuite.SimModelNative.Tests/src/FormulaTests.cpp	Basic constructor tests for MinFormula, MaxFormula, DivFormula, DiffFormula
tests/OSPSuite.SimModelNative.Tests/src/ValuePointTests.cpp	Tests for ValuePoint constructors, copy semantics, and field validation
tests/OSPSuite.SimModelNative.Tests/src/TObjectVectorTests.cpp	Tests for TObjectVector operations including memory management
buildWindows.bat	Added C++ test execution with XML output
buildNix.sh	Integrated C++ test building and execution in Unix build pipeline
OSPSuite.SimModel.sln	Added new test project to Tests solution folder with dependencies
_codeql_detected_source_root	CodeQL configuration file

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[Copilot]

The main() function should be removed from this test file. Google Test automatically provides a main() function when linking with gtest_main (as configured in CMakeLists.txt line 54). Having a custom main() here creates duplicate symbol conflicts during linking and is redundant.

Suggested change

	int main(int argc, char **argv) {
	::testing::InitGoogleTest(&argc, argv);
	return RUN_ALL_TESTS();
	}