Add test for cached exps

Author: ProExpertProg

cpp/test/CMakeLists.txt

@@ -19,6 +19,7 @@ function(add_viriato_test FILE)
 endfunction()
 
 add_viriato_test(exporter.cpp)
+add_viriato_test(exps.cpp)
 add_viriato_test(filter.cpp)
 add_viriato_test(grid.cpp)
 add_viriato_test(transformer.cpp)

cpp/test/exps.cpp

@@ -0,0 +1,83 @@
+#include "grid.hpp"
+
+#include "debug.hpp"
+#include "util.hpp"
+
+#include "CachedExponentials.hpp"
+#include "Exponentials.hpp"
+
+#include <gtest/gtest.h>
+
+namespace ahr::exp {
+
+template <typename Exp, typename ExpT> class TestExps : public ::testing::Test {
+protected:
+  Grid grid{5, 32, 64};
+  Exp exp{grid};
+  ExpT exp_t{grid};
+
+  void check()
+    requires exp::space_like<Exp>
+  {
+    grid.for_each_kxky([&](Dim kx, Dim ky) {
+      EXPECT_THAT(exp(kx, ky), AllClose(exp_t(kx, ky), 1e-16, 1e-15)); // prevent oneline
+    });
+  }
+
+  void check()
+    requires exp::moment_like<Exp>
+  {
+    for (int m = 0; m < grid.M; ++m) {
+      EXPECT_THAT(exp(m), AllClose(exp_t(m), 1e-16, 1e-15));
+    }
+  }
+
+  void test() {
+    Real dt = 1.0;
+    HyperCoefficients hyper = HyperCoefficients::calculate(dt, grid);
+
+    exp.update(hyper, dt);
+    exp_t.update(hyper, dt);
+
+    this->check();
+    this->check(); // Run again
+
+    dt *= 1.2;
+    hyper = HyperCoefficients::calculate(dt, grid);
+    exp.update(hyper, dt);
+    exp_t.update(hyper, dt);
+
+    this->check();
+
+    // Update with the same dt
+    exp.update(hyper, dt);
+    exp_t.update(hyper, dt);
+    this->check();
+
+    // Old dt again
+    exp.update(hyper, 1.0);
+    exp_t.update(hyper, 1.0);
+    this->check();
+  }
+};
+
+/// This struct contains a type definition for the appropriate Cached* class for exp.
+/// It's specialized for space-like/moment-like so they can all use the same test suite.
+template <typename Exp> struct cached;
+
+template <space_like Exp> struct cached<Exp> {
+  using type = CachedKXKY<Exp>;
+};
+
+template <moment_like Exp> struct cached<Exp> {
+  using type = CachedM<Exp>;
+};
+
+template <typename Exp> using TestCachedExps = TestExps<Exp, typename cached<Exp>::type>;
+
+using Types = ::testing::Types<Eta, Nu, NuG, GM>;
+TYPED_TEST_SUITE(TestCachedExps, Types);
+
+TYPED_TEST(TestCachedExps, Exps) { this->test(); }
+
+} // namespace ahr::exp