[Exp PyROOT] Add test for len of a TVectorT

bindings/pyroot_experimental/PyROOT/test/CMakeLists.txt

@@ -46,6 +46,9 @@ ROOT_ADD_PYUNITTEST(pyroot_pyz_tclonesarray_itemaccess tclonesarray_itemaccess.p
 # TArray and subclasses pythonizations
 ROOT_ADD_PYUNITTEST(pyroot_pyz_tarray_len tarray_len.py)
 
+# TVectorT pythonisations
+ROOT_ADD_PYUNITTEST(pyroot_pyz_tvectort_len tvectort_len.py)
+
 # TString pythonisations
 ROOT_ADD_PYUNITTEST(pyroot_pyz_tstring_len tstring_len.py)
 ROOT_ADD_PYUNITTEST(pyroot_pyz_tstring_str_repr tstring_str_repr.py)

bindings/pyroot_experimental/PyROOT/test/tvectort_len.py

+import unittest
+
+import ROOT
+
+
+class TVectorTLen(unittest.TestCase):
+    """
+    Test for the pythonization that allows to get the size of a
+    TVectorT by calling `len` on it.
+    """
+
+    num_elems = 3
+
+    # Tests
+    def test_len(self):
+        v = ROOT.TVectorT[float](self.num_elems)
+        self.assertEqual(len(v), self.num_elems)
+
+
+if __name__ == '__main__':
+    unittest.main()