fix: Protection against v == 0 in template_switch (#1707)

Add a check in `template_switch` methods in case `v == 0` (i.e. no measurements) and add corresponding error message
acts-project · Dec 9, 2022 · ce28f69 · ce28f69
1 parent 6045480
commit ce28f69
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/Core/include/Acts/Utilities/Helpers.hpp b/Core/include/Acts/Utilities/Helpers.hpp
@@ -395,6 +395,11 @@ auto template_switch(size_t v, Args&&... args) {
   if (v == N) {
     return Callable<N>::invoke(std::forward<Args>(args)...);
   }
+  if (v == 0) {
+    std::cerr << "template_switch<Fn, " << N << ", " << NMAX << ">(v=" << v
+              << ") is not valid (v == 0 and N != 0)" << std::endl;
+    std::abort();
+  }
   if constexpr (N < NMAX) {
     return template_switch<Callable, N + 1, NMAX>(v,
                                                   std::forward<Args>(args)...);
@@ -417,6 +422,11 @@ auto template_switch_lambda(size_t v, Lambda&& func, Args&&... args) {
     return func(std::integral_constant<size_t, N>{},
                 std::forward<Args>(args)...);
   }
+  if (v == 0) {
+    std::cerr << "template_switch<Fn, " << N << ", " << NMAX << ">(v=" << v
+              << ") is not valid (v == 0 and N != 0)" << std::endl;
+    std::abort();
+  }
   if constexpr (N < NMAX) {
     return template_switch_lambda<N + 1, NMAX>(v, func,
                                                std::forward<Args>(args)...);