bdb — Debugger framework

Source code: Lib/bdb.py

The bdb module handles basic debugger functions, like setting breakpoints or managing execution via the debugger.

The following exception is defined:

exception bdb.BdbQuit

Exception raised by the Bdb class for quitting the debugger.

The bdb module also defines two classes:

class bdb.Breakpoint(self, file, line, temporary=0, cond=None, funcname=None)

This class implements temporary breakpoints, ignore counts, disabling and (re-)enabling, and conditionals.

Breakpoints are indexed by number through a list called bpbynumber and by (file, line) pairs through bplist. The former points to a single instance of class Breakpoint. The latter points to a list of such instances since there may be more than one breakpoint per line.

When creating a breakpoint, its associated filename should be in canonical form. If a funcname is defined, a breakpoint hit will be counted when the first line of that function is executed. A conditional breakpoint always counts a hit.

Breakpoint instances have the following methods:

deleteMe()

Delete the breakpoint from the list associated to a file/line. If it is the last breakpoint in that position, it also deletes the entry for the file/line.

enable()

Mark the breakpoint as enabled.

disable()

Mark the breakpoint as disabled.

bpformat()

Return a string with all the information about the breakpoint, nicely formatted:

  • The breakpoint number.

  • If it is temporary or not.

  • Its file,line position.

  • The condition that causes a break.

  • If it must be ignored the next N times.

  • The breakpoint hit count.

New in version 3.2.

bpprint(out=None)

Print the output of bpformat() to the file out, or if it is None, to standard output.

class bdb.Bdb(skip=None)

The Bdb class acts as a generic Python debugger base class.

This class takes care of the details of the trace facility; a derived class should implement user interaction. The standard debugger class (pdb.Pdb) is an example.

The skip argument, if given, must be an iterable of glob-style module name patterns. The debugger will not step into frames that originate in a module that matches one of these patterns. Whether a frame is considered to originate in a certain module is determined by the __name__ in the frame globals.

New in version 3.1: The skip argument.

The following methods of Bdb normally don’t need to be overridden.

canonic(filename)

Auxiliary method for getting a filename in a canonical form, that is, as a case-normalized (on case-insensitive filesystems) absolute path, stripped of surrounding angle brackets.

reset()

Set the botframe, stopframe, returnframe and quitting attributes with values ready to start debugging.

trace_dispatch(frame, event, arg)