No Python class registered for C++ class mapnik::enumeration<mapnik::text_transform, 4>

[springmeyer]

Not sure why this is happening or if this ever worked post text_placement refactoring by @herm.

>>> sym = mapnik.TextSymbolizer()
>>> sym.text_transform
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Library/Python/2.7/site-packages/mapnik/__init__.py", line 815, in text_transform
    return self.format.text_transform
TypeError: No Python class registered for C++ class mapnik::enumeration<mapnik::text_transform, 4>

[springmeyer]

looks like it works if set, just not when unset, so this is likely also the boost::optional bug we hit in #1367 and it will impact all text format options as they are optional. ugh....

[lightmare]

I don't see any optionals here, it's more like this issue.

This fixes the above for me:

diff --git a/bindings/python/mapnik_text_placement.cpp b/bindings/python/mapnik_text_placement.cpp
index d149406..0c1c95e 100644
--- a/bindings/python/mapnik_text_placement.cpp
+++ b/bindings/python/mapnik_text_placement.cpp
@@ -390,8 +390,9 @@ void export_text_placement()
        set_old_style expression is just a compatibility wrapper and doesn't need to be exposed in python. */
     ;

-    class_<char_properties>
+    class_with_converter<char_properties>
         ("CharProperties")
+        .def_readwrite_convert("text_transform", &char_properties::text_transform)
         .def(init<char_properties const&>()) //Copy constructor
         .def_readwrite("face_name", &char_properties::face_name)
         .def_readwrite("fontset", &char_properties::fontset)
@@ -401,7 +402,6 @@ void export_text_placement()
         .def_readwrite("text_opacity", &char_properties::text_opacity)
         .def_readwrite("wrap_char", &char_properties::wrap_char)
         .def_readwrite("wrap_before", &char_properties::wrap_before)
-        .def_readwrite("text_transform", &char_properties::text_transform)
         .def_readwrite("fill", &char_properties::fill)
         .def_readwrite("halo_fill", &char_properties::halo_fill)
         .def_readwrite("halo_radius", &char_properties::halo_radius)

[springmeyer]

ah, interesting. I saw optionals here, which is why I assumed #1367.

regarding your patch - I'll try it now...

[springmeyer]

great, patch works, but I have to comment out the .def(init<char_properties const&>()) //Copy constructor otherwise I get this compile error:

bindings/python/mapnik_text_placement.cpp:397:10: error: no member named 'def_readwrite_convert' in
      'boost::python::class_<mapnik::char_properties, boost::python::detail::not_specified,
      boost::python::detail::not_specified, boost::python::detail::not_specified>'; did you mean 'def_readwrite_impl'?
        .def_readwrite_convert("text_transform", &char_properties::text_transform)
         ^~~~~~~~~~~~~~~~~~~~~
         def_readwrite_impl
/opt/boost-50/include/boost/python/class.hpp:474:11: note: 'def_readwrite_impl' declared here
    self& def_readwrite_impl(
          ^
bindings/python/mapnik_text_placement.cpp:397:10: error: cannot refer to member 'def_readwrite_impl' in 'self' (aka
      'class_<mapnik::char_properties, boost::python::detail::not_specified, boost::python::detail::not_specified,
      boost::python::detail::not_specified>') with '.'
        .def_readwrite_convert("text_transform", &char_properties::text_transform)
         ^
/opt/boost-50/include/boost/python/class.hpp:474:11: note: member 'def_readwrite_impl' declared here
    self& def_readwrite_impl(
          ^
2 errors generated.

[herm]

You have to use exactly the same order as in the patch provided by @lightmare.
def_readwrite_convert() returns an object of type class_with_converter again, but
def() returns an object of type class_.

class_ doesn't have the def_readwrite_convert() function. It's not the nicest solution, but at least it works.