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/sandbox/surface_sandbox.cpp

@@ -0,0 +1,48 @@
+#include <print>
+#include <utility>
+
+#include "serif/eos/models/polytropic.hpp"
+#include "serif/geometry/surface/surface.hpp"
+#include "serif/utils/dependencies/computation_cache.hpp"
+
+/**
+ * @brief Prescribe one pressure and evaluate its residual over several already sampled boundary points.
+ *
+ * The EOS catalog and available state select the quantity enforcing the condition. This example binds density, as the
+ * stellar model does; other models may bind another state. IsobaricSurface itself only knows the prescribed pressure.
+ *
+ * The ordinary dependency cache owns preparation. The EOS response is computed once for this pressure-only relation,
+ * then reused across all boundary samples and subsequent changes to their density. No EOS evaluation occurs at graph construction.
+ * Sampling a finite-element field on the boundary is deliberately a separate numerical operation.
+ */
+int main() {
+    namespace surface = serif::geometry::surface;
+    namespace dependencies = serif::utils::dependencies;
+    namespace quantities = serif::dimensions;
+    using Density = serif::discretization::blocks::density::mass;
+    using EOS = serif::eos::models::Polytrope;
+    using State = dependencies::Bindings<dependencies::Binding<quantities::MassDensity, Density>>;
+
+    const EOS equation_of_state{3.0, 0.25};
+    const surface::IsobaricSurface boundary{quantities::PressureValue{0.03125}};
+    const auto context = dependencies::make_dependency_context(
+        dependencies::borrow<surface::keys::EquationOfState>(equation_of_state, dependencies::track_by([](const EOS& model) {
+            return std::pair{model.polytropic_index(), model.polytropic_constant()};
+        })),
+        surface::pressure_condition(boundary),
+        surface::boundary_values<Density>({0.05, 0.1, 0.2})
+    );
+
+    auto graph = surface::make_pressure_surface_graph<EOS, State>();
+    auto cache = dependencies::make_computation_cache<surface::SurfaceFailure>(std::move(graph), context);
+    const auto preparation = cache.try_prepare(context);
+    if (!preparation) {
+        std::println(stderr, "Surface preparation failed: {}", preparation.error().error.message);
+        return 1;
+    }
+
+    for (const auto& point : cache.get<surface::keys::Linearization>()) {
+        std::println("Boundary density residual: {}; derivative: {}", point.residual, point.field_derivatives.get<Density>());
+    }
+    return 0;
+}