Message named pkg/Duration with field builtin_interfaces/Duration is invalid

Riproducete il problema con un pacchetto di messaggi contenente pkg/Duration e un campo builtin_interfaces/Duration, quindi esaminate l'output build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py. Tracciate il codice del generatore che produce gli import in conflitto, aggiornate il comportamento di generazione in modo che il nome del messaggio non venga oscurato ed eseguite i controlli mypy e flake8 segnalati per confermare che il codice generato sia valido.

Generated by Generative AI

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Operating System:

Linux

ROS version or commit hash:

rolling

RMW implementation (if applicable):

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RMW Configuration (if applicable):

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Client library (if applicable):

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'ros2 doctor --report' output

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Steps to reproduce issue

1. Create a message package pkg containing a message type named Duration with a field of type builtin_interfaces/Duration.
2. Compile the workspace and inspect the generated Python code.
3. Run mypy tests and flake8

Expected behavior

Message type pkg/Duration should be valid.

Actual behavior

The generated message Python code is invalid:

 27: /root/target_ws/build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py:87:1: F811 redefinition of unused 'Duration' from line 20
  27: class Duration(rosidl_pycommon.interface_base_classes.BaseMessage, metaclass=Metaclass_Duration):
  27: ^
  27: 
  27: 1     F811 redefinition of unused 'Duration' from line 20

  30: /root/target_ws/build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py:87:1: error: Name "Duration" already defined (possibly by an import)  [no-redef]
  30: /root/target_ws/build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py: note: In member "__eq__" of class "Duration":
  30: /root/target_ws/build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py:151:27: error: "Duration" has no attribute "header"  [attr-defined]
  30: /root/target_ws/build/stamped_msgs/rosidl_generator_py/stamped_msgs/msg/_duration.py:153:25: error: "Duration" has no attribute "data"  [attr-defined]
  30: Found 3 errors in 1 file (checked 46 source files)

Additional information

Indeed, there are multiple places in the generated code that do:

from a.msg import b

But if the message is named pkg.Duration and the type of one of its fields is builtin_interfaces.Duration, then this import shadows the actual pkg.Duration and the code gets either confused, or even invalid.

I think all usages of from a.msg import b should be replaced by import a.msg; .... a.msg.b in the generated code. This way, the name collisions would not happen.