From 6fd9006291c98d911ca946bdc5e87633d200797a Mon Sep 17 00:00:00 2001
From: Johan Larsson <johanlarsson@outlook.com>
Date: Thu, 30 Nov 2023 20:48:14 +0100
Subject: [PATCH] tests: add custom test helper

---
 tests/helpers.hpp | 55 +++++++++++++++++++++++++++++++++++++++++++++++
 tests/test.cpp    | 20 ++++++++---------
 2 files changed, 65 insertions(+), 10 deletions(-)
 create mode 100644 tests/helpers.hpp

diff --git a/tests/helpers.hpp b/tests/helpers.hpp
new file mode 100644
index 0000000..9909b5f
--- /dev/null
+++ b/tests/helpers.hpp
@@ -0,0 +1,55 @@
+#include <catch2/catch_test_macros.hpp>
+#include <catch2/matchers/catch_matchers_templated.hpp>
+
+template<typename T>
+std::vector<double>
+asStdVec(const T& x)
+{
+  std::vector<double> vec(x.data(), x.data() + x.size());
+
+  return vec;
+}
+
+template<typename Range>
+struct VectorApproxEqualMatcher : Catch::Matchers::MatcherGenericBase
+{
+  VectorApproxEqualMatcher(const Range& range, const double eps)
+    : range{ range }
+    , eps{ eps }
+  {
+  }
+
+  template<typename OtherRange>
+  bool match(OtherRange const& other) const
+  {
+
+    if (range.size() != other.size()) {
+      return false;
+    }
+
+    for (int i = 0; i < range.size(); ++i) {
+      if (std::abs(range[i] - other[i]) > eps) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  std::string describe() const override
+  {
+    return "Approximately equal to: " + Catch::rangeToString(asStdVec(range));
+  }
+
+private:
+  const Range& range;
+  const double eps;
+};
+
+template<typename Range>
+auto
+VectorApproxEqual(const Range& range, const double eps = 1e-6)
+  -> VectorApproxEqualMatcher<Range>
+{
+  return VectorApproxEqualMatcher<Range>{ range, eps };
+}
diff --git a/tests/test.cpp b/tests/test.cpp
index b5d8786..faa2a77 100644
--- a/tests/test.cpp
+++ b/tests/test.cpp
@@ -1,10 +1,12 @@
+#include "helpers.hpp"
 #include <Eigen/Core>
 #include <catch2/catch_test_macros.hpp>
+#include <catch2/matchers/catch_matchers.hpp>
 #include <catch2/matchers/catch_matchers_floating_point.hpp>
-#include <catch2/matchers/catch_matchers_range_equals.hpp>
+#include <catch2/matchers/catch_matchers_templated.hpp>
 #include <slope/slope.h>
 
-TEST_CASE("Simple low-dimensional design", "[gaussian, dense]")
+TEST_CASE("Simple low-dimensional design", "[gaussian, dense, ols]")
 {
   using namespace Catch::Matchers;
 
@@ -27,10 +29,9 @@ TEST_CASE("Simple low-dimensional design", "[gaussian, dense]")
   auto no_intercept_no_std =
     slope::slope(x, y, alpha, lambda, "gaussian", false, false);
 
-  REQUIRE_THAT(no_intercept_no_std.betas.coeff(0, 0),
-               WithinAbsMatcher(1, 0.001));
-  REQUIRE_THAT(no_intercept_no_std.betas.coeff(1, 0),
-               WithinAbsMatcher(1, 0.001));
+  Eigen::VectorXd coef = no_intercept_no_std.betas.col(0);
+
+  REQUIRE_THAT(coef, VectorApproxEqual(beta, 1e-4));
 }
 
 TEST_CASE("X is identity", "[gaussian, dense]")
@@ -49,8 +50,7 @@ TEST_CASE("X is identity", "[gaussian, dense]")
 
   Eigen::VectorXd betas = res.betas.col(0);
 
-  REQUIRE_THAT(betas(0), WithinAbsMatcher(4.0, 0.001));
-  REQUIRE_THAT(betas(1), WithinAbsMatcher(3.0, 0.001));
-  REQUIRE_THAT(betas(2), WithinAbsMatcher(2.0, 0.001));
-  REQUIRE_THAT(betas(3), WithinAbsMatcher(1.0, 0.001));
+  std::array<double, 4> expected = { 4.0, 3.0, 2.0, 1.0 };
+
+  REQUIRE_THAT(betas, VectorApproxEqual(expected));
 }