code review: ctor shall raise a TypeError when constructed from something else than a SimplexTree

2 files changed, 11 insertions, 3 deletions

diff --git a/src/python/gudhi/simplex_tree.pyx b/src/python/gudhi/simplex_tree.pyx
index 8f760422..e1685ded 100644
--- a/src/python/gudhi/simplex_tree.pyx
+++ b/src/python/gudhi/simplex_tree.pyx
@@ -47,6 +47,7 @@ cdef class SimplexTree:
         :returns: An empty or a copy simplex tree.
         :rtype: SimplexTree
 
+        :raises TypeError: In case `other` is neither `None`, nor a `SimplexTree`.
         :note: If the `SimplexTree` is a copy, it requires :func:`compute_persistence` to be launched again as the
             persistence result is not copied.
         """
@@ -54,9 +55,12 @@ cdef class SimplexTree:
     # The real cython constructor
     def __cinit__(self, other = None):
         cdef SimplexTree ostr
-        if other and type(other) is SimplexTree:
-            ostr = <SimplexTree> other
-            self.thisptr = <intptr_t>(new Simplex_tree_interface_full_featured(dereference(ostr.get_ptr())))
+        if other:
+            if type(other) is SimplexTree:
+                ostr = <SimplexTree> other
+                self.thisptr = <intptr_t>(new Simplex_tree_interface_full_featured(dereference(ostr.get_ptr())))
+            else:
+                raise TypeError("`other` argument requires to be of type `SimplexTree`, or `None`.")
         else:
             self.thisptr = <intptr_t>(new Simplex_tree_interface_full_featured())
 
diff --git a/src/python/test/test_simplex_tree.py b/src/python/test/test_simplex_tree.py
index 2c2e09a2..a8180ce8 100755
--- a/src/python/test/test_simplex_tree.py
+++ b/src/python/test/test_simplex_tree.py
@@ -511,3 +511,7 @@ def test_simplex_tree_deep_copy_constructor():
     # test double free
     del st
     del st_copy
+
+def test_simplex_tree_constructor_exception():
+    with pytest.raises(TypeError):
+        st = SimplexTree(other = "Construction from a string shall raise an exception")