Remove template, add a test

src/ivoc/ivocvect.cpp

@@ -3876,8 +3876,7 @@ void Vector_reg() {
 #endif
 }
 
-template <typename F>
-int nrn_mlh_gsort(double* vec, int* base_ptr, int total_elems, F cmp) {
+int nrn_mlh_gsort(double* vec, int* base_ptr, int total_elems, int (*cmp)(double, double)) {
     std::sort(base_ptr, base_ptr + total_elems, [&](const int& a, const int& b) {
         return cmp(vec[a], vec[b]) < 0;
     });

src/oc/oc_ansi.h

@@ -104,8 +104,7 @@ std::FILE* hoc_obj_file_arg(int i);
 void hoc_reg_nmodl_text(int type, const char* txt);
 void hoc_reg_nmodl_filename(int type, const char* filename);
 std::size_t nrn_mallinfo(int item);
-template <typename F>
-int nrn_mlh_gsort(double* vec, int* base_ptr, int total_elems, F cmp);
+int nrn_mlh_gsort(double* vec, int* base_ptr, int total_elems, int (*cmp)(double, double));
 void state_discontinuity(int i, double* pd, double d);
 
 IvocVect* vector_arg(int);

test/unit_tests/iovec.cpp

@@ -5,23 +5,41 @@
 
 #include <catch2/catch.hpp>
 
+// This function is the one that is used in all nrn-modeldb-ci
+// Keep as is
+int cmpdfn(double a, double b) {
+    return ((a) <= (b)) ? (((a) == (b)) ? 0 : -1) : 1;
+}
+
 TEST_CASE("Test nrn_mlh_gsort output", "[nrn_gsort]") {
     std::vector<double> input{1.2, -2.5, 5.1};
 
-    std::vector<int> indices(input.size());
-    // all values from 0 to size - 1
-    std::iota(indices.begin(), indices.end(), 0);
+    {
+        std::vector<int> indices(input.size());
+        // all values from 0 to size - 1
+        std::iota(indices.begin(), indices.end(), 0);
+
+        // for comparison
+        auto sorted_input = input;
+        std::sort(sorted_input.begin(), sorted_input.end());
+
+        SECTION("Test sorting") {
+            nrn_mlh_gsort(input.data(), indices.data(), input.size(), cmpdfn);
+            for (auto i = 0; i < input.size(); ++i) {
+                REQUIRE(sorted_input[i] == input[indices[i]]);
+            }
+        }
+    }
 
-    // for comparison
-    auto sorted_input = input;
-    std::sort(sorted_input.begin(), sorted_input.end());
+    {
+        std::vector<int> indices{2, 1, 1};
+        std::vector<int> expected_result{1, 1, 2};  // as -2,5 < 5.1
 
-    SECTION("Test sorting") {
-        nrn_mlh_gsort(input.data(), indices.data(), input.size(), [](double a, double b) {
-            return a < b;
-        });
-        for (auto i = 0; i < input.size(); ++i) {
-            REQUIRE(sorted_input[i] == input[indices[i]]);
+        SECTION("Test sorting with repeted indices") {
+            nrn_mlh_gsort(input.data(), indices.data(), input.size(), cmpdfn);
+            for (auto i = 0; i < input.size(); ++i) {
+                REQUIRE(indices[i] == expected_result[i]);
+            }
         }
     }
 }