[windows][master] Use .pyd as the output suffix for Python module on Windows.

[seanyen]

The .pyd is the file extension for Python extension modules on Windows. This change is to fix the file extension on Windows.

[v4hn]

The problem of handling the separate suffixes looks like cmake should provide an abstraction for it already, given that this is required for all python modules on windows everywhere.

However, it looks like the patch you provide is still the standard way to handle this.

[rhaschke]

Generally, I approve this PR.
What about introducing a cmake macro that marks a library target as a python lib, which allows to hide the complexity / boringness of these three lines behind a single line:
mark_target_as_python_extension(TARGET)

The macro should be defined by ros_core and thus would be automatically included by all packages that depend on ros_core.
On the other hand, this hiding might be not desired. And we might have name clashes if other packages will define such a macro as well.

[v4hn]

The macro should be defined by ros_core and thus would be automatically included by all packages that depend on ros_core.

Sounds like a good idea, I'm not sure you will find someone to review such an addition for ros_comm for ROS1, but at least for ROS2 this seems like a great idea.

I would propose to merge this request nonetheless until such a feature becomes available somewhere.

[rhaschke]

Sorry, I meant moveit_core instead of ros_core. I think, for us, it will be sufficient to have such a macro in MoveIt. I agree with you, @v4hn, that probably nobody will agree to augment ros_comm or even catkin with such a cmake macro.

[v4hn]

Merging with two approvals.

@rhaschke I do not really like the idea of adding this macro only within MoveIt.
Custom project macros always make it much harder to understand the build structure of big code bases.
Until now, MoveIt did a great job at sticking to "standard" cmake/catkin.