test(tests): added test suite

The test suite is extensive. Note that LLMs were used to aid in the development of the test suite. All LLM generated code was manually reviewed.

tests/equations/fixture.cpp

@@ -0,0 +1,106 @@
+#include "serif/tests/equations/fixture.hpp"
+
+#include <algorithm>
+#include <cmath>
+#include <memory>
+
+namespace serif::tests::equations {
+    ::mfem::Mesh make_mesh(::mfem::Element::Type geometry) {
+        auto mesh = ::mfem::Mesh::MakeCartesian3D(3, 1, 1, geometry, 1.5, 1.0, 1.0);
+        ::mfem::Vector center(3);
+        for (int element = 0; element < mesh.GetNE(); ++element) {
+            auto* transformation = mesh.GetElementTransformation(element);
+            transformation->Transform(::mfem::Geometries.GetCenter(transformation->GetGeometryType()), center);
+            mesh.GetElement(element)->SetAttribute(1 + static_cast<int>(center[0] / 0.5));
+        }
+        mesh.SetAttributes();
+        return mesh;
+    }
+
+    ::mfem::Vector constant(int size, double value) {
+        ::mfem::Vector result(size);
+        result = value;
+        return result;
+    }
+
+    ::mfem::Vector deterministic(int size, double phase) {
+        ::mfem::Vector result(size);
+        for (int i = 0; i < size; ++i) {
+            result[i] = 0.1 * std::sin(0.13 * i + phase);
+        }
+        return result;
+    }
+
+    ::mfem::Vector packed(
+        const ::mfem::Vector& density,
+        const ::mfem::Vector& enthalpy,
+        const ::mfem::Vector& displacement
+    ) {
+        ::mfem::Vector result(density.Size() + enthalpy.Size() + displacement.Size());
+        std::copy_n(density.GetData(), density.Size(), result.GetData());
+        std::copy_n(enthalpy.GetData(), enthalpy.Size(), result.GetData() + density.Size());
+        std::copy_n(displacement.GetData(), displacement.Size(), result.GetData() + density.Size() + enthalpy.Size());
+        return result;
+    }
+
+    double relative_error(const ::mfem::Vector& actual, const ::mfem::Vector& expected) {
+        ::mfem::Vector difference(actual);
+        difference -= expected;
+        return difference.Norml2() / std::max(expected.Norml2(), 1.0e-30);
+    }
+
+    Fixture::Fixture(::mfem::Element::Type geometry, ::mfem::Ordering::Type ordering) : Fixture(make_mesh(geometry), ordering) {}
+
+    Fixture::Fixture(::mfem::Mesh supplied_mesh, ::mfem::Ordering::Type ordering) :
+        mesh(std::move(supplied_mesh)),
+        density_space(&mesh, &density_collection),
+        enthalpy_space(&mesh, &enthalpy_collection),
+        potential_space(&mesh, &potential_collection),
+        displacement_space(&mesh, &enthalpy_collection, 3, ordering),
+        compactification(&enthalpy_space),
+        density_binding(density_space),
+        enthalpy_binding(enthalpy_space),
+        displacement_binding(displacement_space),
+        mapper(
+            {},
+            std::make_unique<mapping::compactification::KelvinCompactification>(
+                utils::user_options::KelvinCompactificationOptions{.r_star_ref = 1.0, .r_inf_ref = 4.0}
+            )
+        ) {
+        compactification = 0.0;
+    }
+
+    ::mfem::Vector Fixture::project(
+        const discretization::backend::mfem::DofMap& field,
+        std::function<double(const ::mfem::Vector&)> function
+    ) {
+        ::mfem::FunctionCoefficient coefficient(std::move(function));
+        ::mfem::GridFunction values(&field.space());
+        values.ProjectCoefficient(coefficient);
+        return field.gather(values);
+    }
+
+    ::mfem::Vector Fixture::density(double phase) {
+        return project(density_binding, [phase](const ::mfem::Vector& x) {
+            return 0.55 + 0.025 * x[0] - 0.010 * x[1] + 0.006 * x[2] + 0.03 * phase;
+        });
+    }
+
+    ::mfem::Vector Fixture::enthalpy(double phase) {
+        return project(enthalpy_binding, [phase](const ::mfem::Vector& x) {
+            return 0.90 + 0.020 * x[0] - 0.010 * x[1] + 0.005 * x[2] + 0.02 * phase;
+        });
+    }
+
+    ::mfem::Vector Fixture::displacement(double scale) {
+        ::mfem::VectorFunctionCoefficient coefficient(3, [scale](const ::mfem::Vector& x, ::mfem::Vector& u) {
+            u.SetSize(3);
+            u[0] = scale * (0.03 * x[0] + 0.02 * x[0] * x[1]);
+            u[1] = scale * (-0.02 * x[1] + 0.01 * x[0] * x[2]);
+            u[2] = scale * (0.04 * x[2] - 0.015 * x[0] * x[1]);
+        });
+        ::mfem::GridFunction values(&displacement_space);
+        values.ProjectCoefficient(coefficient);
+        return displacement_binding.gather(values);
+    }
+} // namespace serif::tests::equations