[ros_introspection] Use str instead of unicode in replace_contents

[IamPhytan]

ROS Distro : melodic, noetic

I had the following error when running magical_ros2_conversion_tool :

'ascii' codec can't decode byte 0xe4

Part of it was maybe caused by the fact that the package I am trying to convert has comments with characters that are not part of ASCII. This error is combined with a message from pylint:

NameError: name 'unicode' is not defined

My solution is to replace unicode with str. Once replaced, the package ws then able to run without any problems.

[DLu]

Would you mind sending the source file (or a placeholder source file with the nonASCII characters)?

[IamPhytan]

Here is a repo on which I tried to use magical_ros2_conversion_tool: https://github.com/norlab-ulaval/ros_rslidar/

[DLu]

Did some diggiging, and this looks like it was fixed in #83 here: https://github.com/DLu/roscompile/pull/83/files#diff-c3801915f37d209e220776e077539bf711bb6d734402af8ca2a4f57bf96ee4f1

Were you running from the binary?

[IamPhytan]

No, I didn't run the binary, if there was any. I ran the tool from source, in a catkin workspace

As for the fix, it looks like the following line is not catching UnicodeDecodeErrors. I will fix it in a new commit :

https://github.com/DLu/roscompile/blob/main/ros_introspection/src/ros_introspection/source_code_file.py#L46