Wrote a failing test case for leading zero error in cast from float

I think this was not being picked up in CI due to differences in random number generator state between CTest and running the executable directly

Author: saxbophone

tests/casting.cpp

@@ -56,6 +56,17 @@ TEST_CASE("arby::Nat::from_float() with non-finite value throws std::domain_erro
     }
 }
 
+TEST_CASE("arby::Nat::from_float() with value between 0 and 1") {
+    // NOTE: top range is the last float value > 1
+    long double zero_ish = GENERATE(0.0L, std::nextafter(1.0L, 0.0L));
+    CAPTURE(zero_ish);
+
+    arby::Nat object = arby::Nat::from_float(zero_ish);
+
+    // value should be correct
+    CHECK((long double)object == Approx(std::trunc(zero_ish)));
+}
+
 TEST_CASE("arby::Nat::from_float() with positive value") {
     auto power = GENERATE(0.125, 0.25, 0.5, 1, 2, 4, 8);
     auto value = GENERATE_COPY(