Debugger API

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The debugger API controls debugging more closely from your Python code. It is used to control threaded debugging, and to develop support for debugging embedded scripting or other custom environments.

High-Level API

To use the high-level API, you must first configure and import wingdbstub as described in Debugging Externally Launched Code for code running on the same host as the IDE, or Debugging Remotely Launched Code if you are debugging code running on another host:

  • wingdbstub.Ensure(require_connection=1, require_debugger=1) ensures that the debugger is running and connected to the IDE. If require_connection is true, ValueError will be raised if a connection to the IDE cannot be made. If require_debugger is true, ValueError will be raised if the debugger binaries cannot be found or the debugger cannot be started.

Low-Level API

The low-level API can be used through sys._wing_debugger (after import sys) in debug processes launched from the IDE or those using wingdbstub. In the latter case, the same API is available on wingdbstub.debugger:

  • SetDebugThreadIdents(threads={}, default_policy=1) can be used in multi-threaded code to tell the debugger which threads to debug. Set threads to a dictionary that maps from thread id, as obtained from thread.get_ident(), or thread_id in the PyThreadState, to one of the following values: 0 to run the thread without debug, or 1 to debug the thread and immediately stop it if any thread stops. Set default_policy to the action to take when a thread is not found in the thread map.
  • Break() pauses the free-running debug program on the current line, as if at a breakpoint.
  • SuspendDebug() disables debugging, in order to temporarily avoid debug overhead. This leaves the connection to the IDE intact so that resuming is faster.
  • ResumeDebug() resumes debugging if it has been called as often as SuspendDebug().

    Here is a simple usage example:

import wingdbstub
a = 1 # This line is debugged
wingdbstub.debugger.SuspendDebug()
x = 1 # This is executed without debugging
wingdbstub.debugger.ResumeDebug()
y = 2 # This line is debugged
  • StopDebug() stops debugging completely and disconnects from Wing. The debug program continues executing in non-debug mode and must be restarted to start debugging again.
  • StartDebug(stophere=0, connect=1) starts debugging, optionally connecting back to the IDE and/or stopping immediately afterwards. This does not work after StopDebug() has been called.
  • ProgramQuit() may need to be called before the debug program is exited if kEmbedded was set to 1 in wingdbstub.py. This makes sure the debug connection to the IDE is closed cleanly. See Debugging Embedded Python Code for details on when this is needed.