Fix Solver copyctor issues with swig4.2

Closes AMICI-dev#2275

scripts/downloadAndBuildSwig.sh

@@ -18,13 +18,13 @@ cd "${AMICI_PATH}/ThirdParty/"
 
 if [[ ! -d ${SWIG_DIR} ]]; then
     if [[ ! -f ${SWIG_ARCHIVE} ]]
-        then wget ${SWIG_URL}
+        then wget "${SWIG_URL}"
     fi
 
-    tar -xzf ${SWIG_ARCHIVE}
+    tar -xzf "${SWIG_ARCHIVE}"
 fi
 
-cd ${SWIG_DIR}
+cd "${SWIG_DIR}"
 ./configure \
   --prefix="${PREFIX}" \
   --without-alllang \
@@ -38,6 +38,6 @@ echo "================"
 echo "SWIG installation successful"
 echo
 echo "To use this version of SWIG, add directory ${SWIG_BIN_DIR} to your PATH,"
-echo "e.g. adding the following line to your .bashrc:"
+echo "e.g., adding the following line to your ~/.bashrc:"
 echo "    export PATH=${SWIG_BIN_DIR}:\$PATH"
 echo "================"

swig/solver_cvodes.i

@@ -9,5 +9,12 @@ using namespace amici;
 %newobject amici::CVodeSolver::clone;
 %feature("notabstract") amici::CVodeSolver;
 
+// Required with SWIG 4.2.0 https://github.com/AMICI-dev/AMICI/issues/2275
+%extend amici::CVodeSolver {
+    CVodeSolver(Solver const& solver) {
+        return new CVodeSolver(dynamic_cast<CVodeSolver const&>(solver));
+    }
+}
+
 // Process symbols in header
 %include "amici/solver_cvodes.h"

swig/solver_idas.i

@@ -9,5 +9,12 @@ using namespace amici;
 %newobject amici::IDASolver::clone;
 %feature("notabstract") amici::IDASolver;
 
+// Required for SWIG 4.2.0 https://github.com/AMICI-dev/AMICI/issues/2275
+%extend amici::IDASolver {
+    IDASolver(Solver const& solver) {
+        return new IDASolver(dynamic_cast<IDASolver const&>(solver));
+    }
+}
+
 // Process symbols in header
 %include "amici/solver_idas.h"

tests/cpp/unittests/testMisc.cpp

@@ -261,6 +261,13 @@ TEST(SolverIdasTest, DefaultConstructableAndNotLeaky)
     IDASolver solver;
 }
 
+TEST(SolverIdasTest, CopyCtor)
+{
+    IDASolver solver1;
+    IDASolver solver2(solver1);
+}
+
+
 
 class SolverTest : public ::testing::Test {
   protected: