minor

doc/tutorial.md

@@ -217,6 +217,9 @@ $> echo "2008:32" | build/ydoy2mjd  | build/mjd2ymd
 ## ToDo:
 
 * [] Add documentation
+* [] Verify that tests (especially unit tests) run as supposed do in the Release 
+  build. It seems for example, that `from_mjdepoch` does not run as suppposed to 
+  (even erronuous asserts that should fail, don't!).
 
 ## For Developers
 

include/tpdate.hpp

@@ -773,10 +773,10 @@ template <gconcepts::is_sec_dt T>
 template <typename T, typename = std::enable_if_t<T::is_of_sec_type>>
 #endif
 inline datetime<T> from_mjdepoch(const TwoPartDate &t) noexcept {
-  dso::picoseconds nsec(static_cast<picoseconds::underlying_type>(
+  dso::picoseconds psec(static_cast<picoseconds::underlying_type>(
       t.seconds().seconds() * picoseconds::sec_factor<double>()));
   return datetime<T>(modified_julian_day(t.imjd()),
-                     cast_to<picoseconds, T>(nsec));
+                     cast_to<picoseconds, T>(psec));
 }
 
 } /* namespace dso */

include/tpdate2.hpp

@@ -57,7 +57,7 @@ class TwoPartDate2 {
       : _mjd(b), _fday(s.seconds() / SEC_PER_DAY) {
     this->normalize();
   }
-  
+
   explicit TwoPartDate2(int b = 0,
                         FractionalDays d = FractionalDays{0}) noexcept
       : _mjd(b), _fday(d.days()) {

src/core/fundamental_types_generic_utilities.hpp

@@ -456,9 +456,23 @@ constexpr Strg cast_to(Ssrc s) noexcept {
      * this is: (1/1000)*2000 which is 0 because 1/1000 is 0, but
      * (2000*1)/1000 = 2 which is correct.
      */
-    const auto numerator =
-        s.__member_ref__() * Strg::template sec_factor<long>();
-    return Strg(numerator / Ssrc::template sec_factor<long>());
+
+    /* there is a high chance that this may cause overflow; if we are dealing
+     * with anything higher than microseconds, resort to floating point
+     * compuation.
+     */
+    // const auto numerator =
+    //     s.__member_ref__() * Strg::template sec_factor<long>();
+    if constexpr (Ssrc::template sec_factor<long>() > 1'000'000) {
+      const auto scale = Strg::template sec_factor<double>() /
+                         Ssrc::template sec_factor<double>();
+      const auto fsec = scale * s.__member_ref__();
+      return Strg(static_cast<typename Strg::underlying_type>(fsec));
+    } else {
+      const auto numerator =
+          s.__member_ref__() * Strg::template sec_factor<long>();
+      return Strg(numerator / Ssrc::template sec_factor<long>());
+    }
   }
 }
 

test/unit_tests/CMakeLists.txt

@@ -192,3 +192,7 @@ add_internal_includes(leap_insertion_dates_mjd)
 target_link_libraries(leap_insertion_dates_mjd PRIVATE datetime)
 add_test(NAME leap_insertion_dates_mjd COMMAND leap_insertion_dates_mjd)
 
+add_executable(from_mjdepoch from_mjdepoch.cpp)
+add_internal_includes(from_mjdepoch)
+target_link_libraries(from_mjdepoch PRIVATE datetime)
+add_test(NAME from_mjdepoch COMMAND from_mjdepoch)