feat(Composition): Composition now inherits from abstract base class

The composition object is now a specialization of the abstract base CompositionAbstract. This interface enforces getters but not setters (those are left up to children). The intention here is that other code can specialize particular getters for cases where special handling (like unrestricted amounts of one species) are required.

src/composition/lib/composition.cpp

@@ -223,7 +223,12 @@ namespace fourdst::composition {
                 setNumberFraction(symbols[i], fractions[i]);
             }
         }
-        finalize();
+        if (const bool didFinalize = finalize(); !didFinalize) {
+            std::string msg = "Failed to finalize composition on construction. ";
+            msg += "Construction of a composition object requires that the sum of the fractions vector be 1.\n";
+            LOG_CRITICAL(m_logger, "{}", msg);
+            throw exceptions::InvalidCompositionError(msg);
+        }
     }
 
     Composition::Composition(const Composition &composition) {
@@ -327,7 +332,7 @@ namespace fourdst::composition {
     }
 
     bool Composition::isValidComposition(const std::vector<double>& fractions) const {
-        double sum = std::accumulate(fractions.begin(), fractions.end(), 0.0);
+        const double sum = std::accumulate(fractions.begin(), fractions.end(), 0.0);
         if (sum < 0.999999 || sum > 1.000001) {
             LOG_ERROR(m_logger, "The sum of fractions must be equal to 1 (expected 1, got {}).", sum);
             return false;
@@ -416,7 +421,7 @@ namespace fourdst::composition {
     ) {
         std::vector<std::string> symbols;
         symbols.reserve(species.size());
-        for(const auto& s : species) symbols.push_back(std::string(s.name()));
+        for(const auto& s : species) symbols.emplace_back(s.name());
         return setMassFraction(symbols, mass_fractions);
     }
 
@@ -551,7 +556,12 @@ namespace fourdst::composition {
             double massFraction = fraction * thisMassFrac + otherMassFrac * (1-fraction);
             mixedComposition.setMassFraction(symbol, massFraction);
         }
-        mixedComposition.finalize();
+        if (const bool didFinalize = mixedComposition.finalize(); !didFinalize) {
+            std::string msg = "Failed to finalize mixed composition. ";
+            msg += "This likely indicates an issue with the input compositions not summing to 1.\n";
+            LOG_CRITICAL(m_logger, "{}", msg);
+            throw exceptions::InvalidCompositionError(msg);
+        }
         return mixedComposition;
     }
 
@@ -1016,6 +1026,15 @@ namespace fourdst::composition {
         return m_compositions.contains(symbol);
     }
 
+    bool Composition::hasSpecies(const fourdst::atomic::Species &species) const {
+        for (const auto &entry: m_compositions | std::views::values) {
+            if (entry.isotope() == species) {
+                return true;
+            }
+        }
+        return false;
+    }
+
     bool Composition::contains(
         const atomic::Species &isotope
     ) const {