[Trilinos-Users] PyTrilinos' Init_Argv doesn't account for unicode

[Jonathan Guyer]

I've encountered a problem when importing PyTrilinos from within an ipython session, more specifically when I %run a script in ipython that results in PyTrilinos being imported. E.g., given a file `importerr.py` containing

{{{
import PyTrilinos
}}}

if I `%run importerr.py` from within ipython 0.11, I get 

{{{
TypeError: Init_Argv argument list contains non-string
}}}

(see traceback below [*])



The problem arises because ipython passes `importerr.py` as a unicode string and the `PyString_Check(item)` in TeuchosPYTHON_wrap.cpp fails because a unicode object is not a subclass of a string object. 

Without this check `PyString_AsString(item)` would succeed because it accounts for casting from unicode.
 
The following patches resolve the issue for me in Trilinos 10.6.4 (I see the issue is still present in 10.8.1, although I haven't built it yet)

--- packages/PyTrilinos/src/Epetra_Comm.i.bu	2011-10-05 10:43:53.000000000 -0400
+++ packages/PyTrilinos/src/Epetra_Comm.i	2011-10-05 10:44:30.000000000 -0400
@@ -339,7 +339,7 @@
   for (int i=0; i<argc; ++i)
   {
     PyObject * item = PySequence_GetItem(args, i);
-    if (!PyString_Check(item))
+    if (!PyUnicode_Check(item) && !PyString_Check(item))
     {
       PyErr_SetString(PyExc_TypeError, "Init_Argv argument list contains non-string");
       goto fail;


--- packages/PyTrilinos/src/Teuchos_Comm.i.bu	2011-10-05 10:44:09.000000000 -0400
+++ packages/PyTrilinos/src/Teuchos_Comm.i	2011-10-05 10:44:39.000000000 -0400
@@ -445,7 +445,7 @@
   for (int i=0; i<argc; ++i)
   {
     PyObject * item = PySequence_GetItem(args, i);
-    if (!PyString_Check(item))
+    if (!PyUnicode_Check(item) && !PyString_Check(item))
     {
       PyErr_SetString(PyExc_TypeError, "Init_Argv argument list contains non-string");
       goto fail;




[*] Traceback:

{{{
In [1]: %run importerr.py
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
/Users/guyer/.virtualenvs/virtualbrew/build/importerr.py in <module>()
----> 1 import PyTrilinos

/Users/guyer/.virtualenvs/virtualbrew/lib/python2.7/site-packages/PyTrilinos/__init__.py in <module>()
    116 # PyTrilinos.NOX namespace completely before we need to use it.

    117 if ('NOX' in __all__):
--> 118     import NOX
    119     if (NOX.Have_Epetra):
    120         import NOX.Epetra

/Users/guyer/.virtualenvs/virtualbrew/lib/python2.7/site-packages/PyTrilinos/NOX/__init__.py in <module>()
    190 SwigPyIterator_swigregister(SwigPyIterator)
    191 
--> 192 import PyTrilinos.Teuchos
    193 Have_Epetra = ___init__.Have_Epetra
    194 

/Users/guyer/.virtualenvs/virtualbrew/lib/python2.7/site-packages/PyTrilinos/Teuchos.py in <module>()
   4569 # Call MPI_Init if appropriate

   4570 import sys
-> 4571 Init_Argv(sys.argv)
   4572 del sys
   4573 

/Users/guyer/.virtualenvs/virtualbrew/lib/python2.7/site-packages/PyTrilinos/Teuchos.py in Init_Argv(*args)
   4200 def Init_Argv(*args):
   4201   """Init_Argv(PyObject args) -> PyObject"""
-> 4202   return _Teuchos.Init_Argv(*args)
   4203 
   4204 def Finalize(*args):

TypeError: Init_Argv argument list contains non-string
}}}