872 lines
31 KiB
Python
872 lines
31 KiB
Python
"""Debugger basics"""
|
|
|
|
import fnmatch
|
|
import sys
|
|
import os
|
|
from inspect import CO_GENERATOR, CO_COROUTINE, CO_ASYNC_GENERATOR
|
|
|
|
__all__ = ["BdbQuit", "Bdb", "Breakpoint"]
|
|
|
|
GENERATOR_AND_COROUTINE_FLAGS = CO_GENERATOR | CO_COROUTINE | CO_ASYNC_GENERATOR
|
|
|
|
|
|
class BdbQuit(Exception):
|
|
"""Exception to give up completely."""
|
|
|
|
|
|
class Bdb:
|
|
"""Generic Python debugger base class.
|
|
|
|
This class takes care of details of the trace facility;
|
|
a derived class should implement user interaction.
|
|
The standard debugger class (pdb.Pdb) is an example.
|
|
|
|
The optional skip argument 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.
|
|
"""
|
|
|
|
def __init__(self, skip=None):
|
|
self.skip = set(skip) if skip else None
|
|
self.breaks = {}
|
|
self.fncache = {}
|
|
self.frame_returning = None
|
|
|
|
def canonic(self, filename):
|
|
"""Return canonical form of filename.
|
|
|
|
For real filenames, the canonical form is a case-normalized (on
|
|
case insenstive filesystems) absolute path. 'Filenames' with
|
|
angle brackets, such as "<stdin>", generated in interactive
|
|
mode, are returned unchanged.
|
|
"""
|
|
if filename == "<" + filename[1:-1] + ">":
|
|
return filename
|
|
canonic = self.fncache.get(filename)
|
|
if not canonic:
|
|
canonic = os.path.abspath(filename)
|
|
canonic = os.path.normcase(canonic)
|
|
self.fncache[filename] = canonic
|
|
return canonic
|
|
|
|
def reset(self):
|
|
"""Set values of attributes as ready to start debugging."""
|
|
import linecache
|
|
linecache.checkcache()
|
|
self.botframe = None
|
|
self._set_stopinfo(None, None)
|
|
|
|
def trace_dispatch(self, frame, event, arg):
|
|
"""Dispatch a trace function for debugged frames based on the event.
|
|
|
|
This function is installed as the trace function for debugged
|
|
frames. Its return value is the new trace function, which is
|
|
usually itself. The default implementation decides how to
|
|
dispatch a frame, depending on the type of event (passed in as a
|
|
string) that is about to be executed.
|
|
|
|
The event can be one of the following:
|
|
line: A new line of code is going to be executed.
|
|
call: A function is about to be called or another code block
|
|
is entered.
|
|
return: A function or other code block is about to return.
|
|
exception: An exception has occurred.
|
|
c_call: A C function is about to be called.
|
|
c_return: A C function has returned.
|
|
c_exception: A C function has raised an exception.
|
|
|
|
For the Python events, specialized functions (see the dispatch_*()
|
|
methods) are called. For the C events, no action is taken.
|
|
|
|
The arg parameter depends on the previous event.
|
|
"""
|
|
if self.quitting:
|
|
return # None
|
|
if event == 'line':
|
|
return self.dispatch_line(frame)
|
|
if event == 'call':
|
|
return self.dispatch_call(frame, arg)
|
|
if event == 'return':
|
|
return self.dispatch_return(frame, arg)
|
|
if event == 'exception':
|
|
return self.dispatch_exception(frame, arg)
|
|
if event == 'c_call':
|
|
return self.trace_dispatch
|
|
if event == 'c_exception':
|
|
return self.trace_dispatch
|
|
if event == 'c_return':
|
|
return self.trace_dispatch
|
|
print('bdb.Bdb.dispatch: unknown debugging event:', repr(event))
|
|
return self.trace_dispatch
|
|
|
|
def dispatch_line(self, frame):
|
|
"""Invoke user function and return trace function for line event.
|
|
|
|
If the debugger stops on the current line, invoke
|
|
self.user_line(). Raise BdbQuit if self.quitting is set.
|
|
Return self.trace_dispatch to continue tracing in this scope.
|
|
"""
|
|
if self.stop_here(frame) or self.break_here(frame):
|
|
self.user_line(frame)
|
|
if self.quitting: raise BdbQuit
|
|
return self.trace_dispatch
|
|
|
|
def dispatch_call(self, frame, arg):
|
|
"""Invoke user function and return trace function for call event.
|
|
|
|
If the debugger stops on this function call, invoke
|
|
self.user_call(). Raise BbdQuit if self.quitting is set.
|
|
Return self.trace_dispatch to continue tracing in this scope.
|
|
"""
|
|
# XXX 'arg' is no longer used
|
|
if self.botframe is None:
|
|
# First call of dispatch since reset()
|
|
self.botframe = frame.f_back # (CT) Note that this may also be None!
|
|
return self.trace_dispatch
|
|
if not (self.stop_here(frame) or self.break_anywhere(frame)):
|
|
# No need to trace this function
|
|
return # None
|
|
# Ignore call events in generator except when stepping.
|
|
if self.stopframe and frame.f_code.co_flags & GENERATOR_AND_COROUTINE_FLAGS:
|
|
return self.trace_dispatch
|
|
self.user_call(frame, arg)
|
|
if self.quitting: raise BdbQuit
|
|
return self.trace_dispatch
|
|
|
|
def dispatch_return(self, frame, arg):
|
|
"""Invoke user function and return trace function for return event.
|
|
|
|
If the debugger stops on this function return, invoke
|
|
self.user_return(). Raise BdbQuit if self.quitting is set.
|
|
Return self.trace_dispatch to continue tracing in this scope.
|
|
"""
|
|
if self.stop_here(frame) or frame == self.returnframe:
|
|
# Ignore return events in generator except when stepping.
|
|
if self.stopframe and frame.f_code.co_flags & GENERATOR_AND_COROUTINE_FLAGS:
|
|
return self.trace_dispatch
|
|
try:
|
|
self.frame_returning = frame
|
|
self.user_return(frame, arg)
|
|
finally:
|
|
self.frame_returning = None
|
|
if self.quitting: raise BdbQuit
|
|
# The user issued a 'next' or 'until' command.
|
|
if self.stopframe is frame and self.stoplineno != -1:
|
|
self._set_stopinfo(None, None)
|
|
return self.trace_dispatch
|
|
|
|
def dispatch_exception(self, frame, arg):
|
|
"""Invoke user function and return trace function for exception event.
|
|
|
|
If the debugger stops on this exception, invoke
|
|
self.user_exception(). Raise BdbQuit if self.quitting is set.
|
|
Return self.trace_dispatch to continue tracing in this scope.
|
|
"""
|
|
if self.stop_here(frame):
|
|
# When stepping with next/until/return in a generator frame, skip
|
|
# the internal StopIteration exception (with no traceback)
|
|
# triggered by a subiterator run with the 'yield from' statement.
|
|
if not (frame.f_code.co_flags & GENERATOR_AND_COROUTINE_FLAGS
|
|
and arg[0] is StopIteration and arg[2] is None):
|
|
self.user_exception(frame, arg)
|
|
if self.quitting: raise BdbQuit
|
|
# Stop at the StopIteration or GeneratorExit exception when the user
|
|
# has set stopframe in a generator by issuing a return command, or a
|
|
# next/until command at the last statement in the generator before the
|
|
# exception.
|
|
elif (self.stopframe and frame is not self.stopframe
|
|
and self.stopframe.f_code.co_flags & GENERATOR_AND_COROUTINE_FLAGS
|
|
and arg[0] in (StopIteration, GeneratorExit)):
|
|
self.user_exception(frame, arg)
|
|
if self.quitting: raise BdbQuit
|
|
|
|
return self.trace_dispatch
|
|
|
|
# Normally derived classes don't override the following
|
|
# methods, but they may if they want to redefine the
|
|
# definition of stopping and breakpoints.
|
|
|
|
def is_skipped_module(self, module_name):
|
|
"Return True if module_name matches any skip pattern."
|
|
if module_name is None: # some modules do not have names
|
|
return False
|
|
for pattern in self.skip:
|
|
if fnmatch.fnmatch(module_name, pattern):
|
|
return True
|
|
return False
|
|
|
|
def stop_here(self, frame):
|
|
"Return True if frame is below the starting frame in the stack."
|
|
# (CT) stopframe may now also be None, see dispatch_call.
|
|
# (CT) the former test for None is therefore removed from here.
|
|
if self.skip and \
|
|
self.is_skipped_module(frame.f_globals.get('__name__')):
|
|
return False
|
|
if frame is self.stopframe:
|
|
if self.stoplineno == -1:
|
|
return False
|
|
return frame.f_lineno >= self.stoplineno
|
|
if not self.stopframe:
|
|
return True
|
|
return False
|
|
|
|
def break_here(self, frame):
|
|
"""Return True if there is an effective breakpoint for this line.
|
|
|
|
Check for line or function breakpoint and if in effect.
|
|
Delete temporary breakpoints if effective() says to.
|
|
"""
|
|
filename = self.canonic(frame.f_code.co_filename)
|
|
if filename not in self.breaks:
|
|
return False
|
|
lineno = frame.f_lineno
|
|
if lineno not in self.breaks[filename]:
|
|
# The line itself has no breakpoint, but maybe the line is the
|
|
# first line of a function with breakpoint set by function name.
|
|
lineno = frame.f_code.co_firstlineno
|
|
if lineno not in self.breaks[filename]:
|
|
return False
|
|
|
|
# flag says ok to delete temp. bp
|
|
(bp, flag) = effective(filename, lineno, frame)
|
|
if bp:
|
|
self.currentbp = bp.number
|
|
if (flag and bp.temporary):
|
|
self.do_clear(str(bp.number))
|
|
return True
|
|
else:
|
|
return False
|
|
|
|
def do_clear(self, arg):
|
|
"""Remove temporary breakpoint.
|
|
|
|
Must implement in derived classes or get NotImplementedError.
|
|
"""
|
|
raise NotImplementedError("subclass of bdb must implement do_clear()")
|
|
|
|
def break_anywhere(self, frame):
|
|
"""Return True if there is any breakpoint for frame's filename.
|
|
"""
|
|
return self.canonic(frame.f_code.co_filename) in self.breaks
|
|
|
|
# Derived classes should override the user_* methods
|
|
# to gain control.
|
|
|
|
def user_call(self, frame, argument_list):
|
|
"""Called if we might stop in a function."""
|
|
pass
|
|
|
|
def user_line(self, frame):
|
|
"""Called when we stop or break at a line."""
|
|
pass
|
|
|
|
def user_return(self, frame, return_value):
|
|
"""Called when a return trap is set here."""
|
|
pass
|
|
|
|
def user_exception(self, frame, exc_info):
|
|
"""Called when we stop on an exception."""
|
|
pass
|
|
|
|
def _set_stopinfo(self, stopframe, returnframe, stoplineno=0):
|
|
"""Set the attributes for stopping.
|
|
|
|
If stoplineno is greater than or equal to 0, then stop at line
|
|
greater than or equal to the stopline. If stoplineno is -1, then
|
|
don't stop at all.
|
|
"""
|
|
self.stopframe = stopframe
|
|
self.returnframe = returnframe
|
|
self.quitting = False
|
|
# stoplineno >= 0 means: stop at line >= the stoplineno
|
|
# stoplineno -1 means: don't stop at all
|
|
self.stoplineno = stoplineno
|
|
|
|
# Derived classes and clients can call the following methods
|
|
# to affect the stepping state.
|
|
|
|
def set_until(self, frame, lineno=None):
|
|
"""Stop when the line with the lineno greater than the current one is
|
|
reached or when returning from current frame."""
|
|
# the name "until" is borrowed from gdb
|
|
if lineno is None:
|
|
lineno = frame.f_lineno + 1
|
|
self._set_stopinfo(frame, frame, lineno)
|
|
|
|
def set_step(self):
|
|
"""Stop after one line of code."""
|
|
# Issue #13183: pdb skips frames after hitting a breakpoint and running
|
|
# step commands.
|
|
# Restore the trace function in the caller (that may not have been set
|
|
# for performance reasons) when returning from the current frame.
|
|
if self.frame_returning:
|
|
caller_frame = self.frame_returning.f_back
|
|
if caller_frame and not caller_frame.f_trace:
|
|
caller_frame.f_trace = self.trace_dispatch
|
|
self._set_stopinfo(None, None)
|
|
|
|
def set_next(self, frame):
|
|
"""Stop on the next line in or below the given frame."""
|
|
self._set_stopinfo(frame, None)
|
|
|
|
def set_return(self, frame):
|
|
"""Stop when returning from the given frame."""
|
|
if frame.f_code.co_flags & GENERATOR_AND_COROUTINE_FLAGS:
|
|
self._set_stopinfo(frame, None, -1)
|
|
else:
|
|
self._set_stopinfo(frame.f_back, frame)
|
|
|
|
def set_trace(self, frame=None):
|
|
"""Start debugging from frame.
|
|
|
|
If frame is not specified, debugging starts from caller's frame.
|
|
"""
|
|
if frame is None:
|
|
frame = sys._getframe().f_back
|
|
self.reset()
|
|
while frame:
|
|
frame.f_trace = self.trace_dispatch
|
|
self.botframe = frame
|
|
frame = frame.f_back
|
|
self.set_step()
|
|
sys.settrace(self.trace_dispatch)
|
|
|
|
def set_continue(self):
|
|
"""Stop only at breakpoints or when finished.
|
|
|
|
If there are no breakpoints, set the system trace function to None.
|
|
"""
|
|
# Don't stop except at breakpoints or when finished
|
|
self._set_stopinfo(self.botframe, None, -1)
|
|
if not self.breaks:
|
|
# no breakpoints; run without debugger overhead
|
|
sys.settrace(None)
|
|
frame = sys._getframe().f_back
|
|
while frame and frame is not self.botframe:
|
|
del frame.f_trace
|
|
frame = frame.f_back
|
|
|
|
def set_quit(self):
|
|
"""Set quitting attribute to True.
|
|
|
|
Raises BdbQuit exception in the next call to a dispatch_*() method.
|
|
"""
|
|
self.stopframe = self.botframe
|
|
self.returnframe = None
|
|
self.quitting = True
|
|
sys.settrace(None)
|
|
|
|
# Derived classes and clients can call the following methods
|
|
# to manipulate breakpoints. These methods return an
|
|
# error message if something went wrong, None if all is well.
|
|
# Set_break prints out the breakpoint line and file:lineno.
|
|
# Call self.get_*break*() to see the breakpoints or better
|
|
# for bp in Breakpoint.bpbynumber: if bp: bp.bpprint().
|
|
|
|
def set_break(self, filename, lineno, temporary=False, cond=None,
|
|
funcname=None):
|
|
"""Set a new breakpoint for filename:lineno.
|
|
|
|
If lineno doesn't exist for the filename, return an error message.
|
|
The filename should be in canonical form.
|
|
"""
|
|
filename = self.canonic(filename)
|
|
import linecache # Import as late as possible
|
|
line = linecache.getline(filename, lineno)
|
|
if not line:
|
|
return 'Line %s:%d does not exist' % (filename, lineno)
|
|
list = self.breaks.setdefault(filename, [])
|
|
if lineno not in list:
|
|
list.append(lineno)
|
|
bp = Breakpoint(filename, lineno, temporary, cond, funcname)
|
|
return None
|
|
|
|
def _prune_breaks(self, filename, lineno):
|
|
"""Prune breakpoints for filname:lineno.
|
|
|
|
A list of breakpoints is maintained in the Bdb instance and in
|
|
the Breakpoint class. If a breakpoint in the Bdb instance no
|
|
longer exists in the Breakpoint class, then it's removed from the
|
|
Bdb instance.
|
|
"""
|
|
if (filename, lineno) not in Breakpoint.bplist:
|
|
self.breaks[filename].remove(lineno)
|
|
if not self.breaks[filename]:
|
|
del self.breaks[filename]
|
|
|
|
def clear_break(self, filename, lineno):
|
|
"""Delete breakpoints for filename:lineno.
|
|
|
|
If no breakpoints were set, return an error message.
|
|
"""
|
|
filename = self.canonic(filename)
|
|
if filename not in self.breaks:
|
|
return 'There are no breakpoints in %s' % filename
|
|
if lineno not in self.breaks[filename]:
|
|
return 'There is no breakpoint at %s:%d' % (filename, lineno)
|
|
# If there's only one bp in the list for that file,line
|
|
# pair, then remove the breaks entry
|
|
for bp in Breakpoint.bplist[filename, lineno][:]:
|
|
bp.deleteMe()
|
|
self._prune_breaks(filename, lineno)
|
|
return None
|
|
|
|
def clear_bpbynumber(self, arg):
|
|
"""Delete a breakpoint by its index in Breakpoint.bpbynumber.
|
|
|
|
If arg is invalid, return an error message.
|
|
"""
|
|
try:
|
|
bp = self.get_bpbynumber(arg)
|
|
except ValueError as err:
|
|
return str(err)
|
|
bp.deleteMe()
|
|
self._prune_breaks(bp.file, bp.line)
|
|
return None
|
|
|
|
def clear_all_file_breaks(self, filename):
|
|
"""Delete all breakpoints in filename.
|
|
|
|
If none were set, return an error message.
|
|
"""
|
|
filename = self.canonic(filename)
|
|
if filename not in self.breaks:
|
|
return 'There are no breakpoints in %s' % filename
|
|
for line in self.breaks[filename]:
|
|
blist = Breakpoint.bplist[filename, line]
|
|
for bp in blist:
|
|
bp.deleteMe()
|
|
del self.breaks[filename]
|
|
return None
|
|
|
|
def clear_all_breaks(self):
|
|
"""Delete all existing breakpoints.
|
|
|
|
If none were set, return an error message.
|
|
"""
|
|
if not self.breaks:
|
|
return 'There are no breakpoints'
|
|
for bp in Breakpoint.bpbynumber:
|
|
if bp:
|
|
bp.deleteMe()
|
|
self.breaks = {}
|
|
return None
|
|
|
|
def get_bpbynumber(self, arg):
|
|
"""Return a breakpoint by its index in Breakpoint.bybpnumber.
|
|
|
|
For invalid arg values or if the breakpoint doesn't exist,
|
|
raise a ValueError.
|
|
"""
|
|
if not arg:
|
|
raise ValueError('Breakpoint number expected')
|
|
try:
|
|
number = int(arg)
|
|
except ValueError:
|
|
raise ValueError('Non-numeric breakpoint number %s' % arg) from None
|
|
try:
|
|
bp = Breakpoint.bpbynumber[number]
|
|
except IndexError:
|
|
raise ValueError('Breakpoint number %d out of range' % number) from None
|
|
if bp is None:
|
|
raise ValueError('Breakpoint %d already deleted' % number)
|
|
return bp
|
|
|
|
def get_break(self, filename, lineno):
|
|
"""Return True if there is a breakpoint for filename:lineno."""
|
|
filename = self.canonic(filename)
|
|
return filename in self.breaks and \
|
|
lineno in self.breaks[filename]
|
|
|
|
def get_breaks(self, filename, lineno):
|
|
"""Return all breakpoints for filename:lineno.
|
|
|
|
If no breakpoints are set, return an empty list.
|
|
"""
|
|
filename = self.canonic(filename)
|
|
return filename in self.breaks and \
|
|
lineno in self.breaks[filename] and \
|
|
Breakpoint.bplist[filename, lineno] or []
|
|
|
|
def get_file_breaks(self, filename):
|
|
"""Return all lines with breakpoints for filename.
|
|
|
|
If no breakpoints are set, return an empty list.
|
|
"""
|
|
filename = self.canonic(filename)
|
|
if filename in self.breaks:
|
|
return self.breaks[filename]
|
|
else:
|
|
return []
|
|
|
|
def get_all_breaks(self):
|
|
"""Return all breakpoints that are set."""
|
|
return self.breaks
|
|
|
|
# Derived classes and clients can call the following method
|
|
# to get a data structure representing a stack trace.
|
|
|
|
def get_stack(self, f, t):
|
|
"""Return a list of (frame, lineno) in a stack trace and a size.
|
|
|
|
List starts with original calling frame, if there is one.
|
|
Size may be number of frames above or below f.
|
|
"""
|
|
stack = []
|
|
if t and t.tb_frame is f:
|
|
t = t.tb_next
|
|
while f is not None:
|
|
stack.append((f, f.f_lineno))
|
|
if f is self.botframe:
|
|
break
|
|
f = f.f_back
|
|
stack.reverse()
|
|
i = max(0, len(stack) - 1)
|
|
while t is not None:
|
|
stack.append((t.tb_frame, t.tb_lineno))
|
|
t = t.tb_next
|
|
if f is None:
|
|
i = max(0, len(stack) - 1)
|
|
return stack, i
|
|
|
|
def format_stack_entry(self, frame_lineno, lprefix=': '):
|
|
"""Return a string with information about a stack entry.
|
|
|
|
The stack entry frame_lineno is a (frame, lineno) tuple. The
|
|
return string contains the canonical filename, the function name
|
|
or '<lambda>', the input arguments, the return value, and the
|
|
line of code (if it exists).
|
|
|
|
"""
|
|
import linecache, reprlib
|
|
frame, lineno = frame_lineno
|
|
filename = self.canonic(frame.f_code.co_filename)
|
|
s = '%s(%r)' % (filename, lineno)
|
|
if frame.f_code.co_name:
|
|
s += frame.f_code.co_name
|
|
else:
|
|
s += "<lambda>"
|
|
if '__args__' in frame.f_locals:
|
|
args = frame.f_locals['__args__']
|
|
else:
|
|
args = None
|
|
if args:
|
|
s += reprlib.repr(args)
|
|
else:
|
|
s += '()'
|
|
if '__return__' in frame.f_locals:
|
|
rv = frame.f_locals['__return__']
|
|
s += '->'
|
|
s += reprlib.repr(rv)
|
|
line = linecache.getline(filename, lineno, frame.f_globals)
|
|
if line:
|
|
s += lprefix + line.strip()
|
|
return s
|
|
|
|
# The following methods can be called by clients to use
|
|
# a debugger to debug a statement or an expression.
|
|
# Both can be given as a string, or a code object.
|
|
|
|
def run(self, cmd, globals=None, locals=None):
|
|
"""Debug a statement executed via the exec() function.
|
|
|
|
globals defaults to __main__.dict; locals defaults to globals.
|
|
"""
|
|
if globals is None:
|
|
import __main__
|
|
globals = __main__.__dict__
|
|
if locals is None:
|
|
locals = globals
|
|
self.reset()
|
|
if isinstance(cmd, str):
|
|
cmd = compile(cmd, "<string>", "exec")
|
|
sys.settrace(self.trace_dispatch)
|
|
try:
|
|
exec(cmd, globals, locals)
|
|
except BdbQuit:
|
|
pass
|
|
finally:
|
|
self.quitting = True
|
|
sys.settrace(None)
|
|
|
|
def runeval(self, expr, globals=None, locals=None):
|
|
"""Debug an expression executed via the eval() function.
|
|
|
|
globals defaults to __main__.dict; locals defaults to globals.
|
|
"""
|
|
if globals is None:
|
|
import __main__
|
|
globals = __main__.__dict__
|
|
if locals is None:
|
|
locals = globals
|
|
self.reset()
|
|
sys.settrace(self.trace_dispatch)
|
|
try:
|
|
return eval(expr, globals, locals)
|
|
except BdbQuit:
|
|
pass
|
|
finally:
|
|
self.quitting = True
|
|
sys.settrace(None)
|
|
|
|
def runctx(self, cmd, globals, locals):
|
|
"""For backwards-compatibility. Defers to run()."""
|
|
# B/W compatibility
|
|
self.run(cmd, globals, locals)
|
|
|
|
# This method is more useful to debug a single function call.
|
|
|
|
def runcall(self, func, *args, **kwds):
|
|
"""Debug a single function call.
|
|
|
|
Return the result of the function call.
|
|
"""
|
|
self.reset()
|
|
sys.settrace(self.trace_dispatch)
|
|
res = None
|
|
try:
|
|
res = func(*args, **kwds)
|
|
except BdbQuit:
|
|
pass
|
|
finally:
|
|
self.quitting = True
|
|
sys.settrace(None)
|
|
return res
|
|
|
|
|
|
def set_trace():
|
|
"""Start debugging with a Bdb instance from the caller's frame."""
|
|
Bdb().set_trace()
|
|
|
|
|
|
class Breakpoint:
|
|
"""Breakpoint class.
|
|
|
|
Implements temporary breakpoints, ignore counts, disabling and
|
|
(re)-enabling, and conditionals.
|
|
|
|
Breakpoints are indexed by number through bpbynumber and by
|
|
the (file, line) tuple using 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 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.
|
|
"""
|
|
|
|
# XXX Keeping state in the class is a mistake -- this means
|
|
# you cannot have more than one active Bdb instance.
|
|
|
|
next = 1 # Next bp to be assigned
|
|
bplist = {} # indexed by (file, lineno) tuple
|
|
bpbynumber = [None] # Each entry is None or an instance of Bpt
|
|
# index 0 is unused, except for marking an
|
|
# effective break .... see effective()
|
|
|
|
def __init__(self, file, line, temporary=False, cond=None, funcname=None):
|
|
self.funcname = funcname
|
|
# Needed if funcname is not None.
|
|
self.func_first_executable_line = None
|
|
self.file = file # This better be in canonical form!
|
|
self.line = line
|
|
self.temporary = temporary
|
|
self.cond = cond
|
|
self.enabled = True
|
|
self.ignore = 0
|
|
self.hits = 0
|
|
self.number = Breakpoint.next
|
|
Breakpoint.next += 1
|
|
# Build the two lists
|
|
self.bpbynumber.append(self)
|
|
if (file, line) in self.bplist:
|
|
self.bplist[file, line].append(self)
|
|
else:
|
|
self.bplist[file, line] = [self]
|
|
|
|
def deleteMe(self):
|
|
"""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.
|
|
"""
|
|
|
|
index = (self.file, self.line)
|
|
self.bpbynumber[self.number] = None # No longer in list
|
|
self.bplist[index].remove(self)
|
|
if not self.bplist[index]:
|
|
# No more bp for this f:l combo
|
|
del self.bplist[index]
|
|
|
|
def enable(self):
|
|
"""Mark the breakpoint as enabled."""
|
|
self.enabled = True
|
|
|
|
def disable(self):
|
|
"""Mark the breakpoint as disabled."""
|
|
self.enabled = False
|
|
|
|
def bpprint(self, out=None):
|
|
"""Print the output of bpformat().
|
|
|
|
The optional out argument directs where the output is sent
|
|
and defaults to standard output.
|
|
"""
|
|
if out is None:
|
|
out = sys.stdout
|
|
print(self.bpformat(), file=out)
|
|
|
|
def bpformat(self):
|
|
"""Return a string with information about the breakpoint.
|
|
|
|
The information includes the breakpoint number, temporary
|
|
status, file:line position, break condition, number of times to
|
|
ignore, and number of times hit.
|
|
|
|
"""
|
|
if self.temporary:
|
|
disp = 'del '
|
|
else:
|
|
disp = 'keep '
|
|
if self.enabled:
|
|
disp = disp + 'yes '
|
|
else:
|
|
disp = disp + 'no '
|
|
ret = '%-4dbreakpoint %s at %s:%d' % (self.number, disp,
|
|
self.file, self.line)
|
|
if self.cond:
|
|
ret += '\n\tstop only if %s' % (self.cond,)
|
|
if self.ignore:
|
|
ret += '\n\tignore next %d hits' % (self.ignore,)
|
|
if self.hits:
|
|
if self.hits > 1:
|
|
ss = 's'
|
|
else:
|
|
ss = ''
|
|
ret += '\n\tbreakpoint already hit %d time%s' % (self.hits, ss)
|
|
return ret
|
|
|
|
def __str__(self):
|
|
"Return a condensed description of the breakpoint."
|
|
return 'breakpoint %s at %s:%s' % (self.number, self.file, self.line)
|
|
|
|
# -----------end of Breakpoint class----------
|
|
|
|
|
|
def checkfuncname(b, frame):
|
|
"""Return True if break should happen here.
|
|
|
|
Whether a break should happen depends on the way that b (the breakpoint)
|
|
was set. If it was set via line number, check if b.line is the same as
|
|
the one in the frame. If it was set via function name, check if this is
|
|
the right function and if it is on the first executable line.
|
|
"""
|
|
if not b.funcname:
|
|
# Breakpoint was set via line number.
|
|
if b.line != frame.f_lineno:
|
|
# Breakpoint was set at a line with a def statement and the function
|
|
# defined is called: don't break.
|
|
return False
|
|
return True
|
|
|
|
# Breakpoint set via function name.
|
|
if frame.f_code.co_name != b.funcname:
|
|
# It's not a function call, but rather execution of def statement.
|
|
return False
|
|
|
|
# We are in the right frame.
|
|
if not b.func_first_executable_line:
|
|
# The function is entered for the 1st time.
|
|
b.func_first_executable_line = frame.f_lineno
|
|
|
|
if b.func_first_executable_line != frame.f_lineno:
|
|
# But we are not at the first line number: don't break.
|
|
return False
|
|
return True
|
|
|
|
|
|
# Determines if there is an effective (active) breakpoint at this
|
|
# line of code. Returns breakpoint number or 0 if none
|
|
def effective(file, line, frame):
|
|
"""Determine which breakpoint for this file:line is to be acted upon.
|
|
|
|
Called only if we know there is a breakpoint at this location. Return
|
|
the breakpoint that was triggered and a boolean that indicates if it is
|
|
ok to delete a temporary breakpoint. Return (None, None) if there is no
|
|
matching breakpoint.
|
|
"""
|
|
possibles = Breakpoint.bplist[file, line]
|
|
for b in possibles:
|
|
if not b.enabled:
|
|
continue
|
|
if not checkfuncname(b, frame):
|
|
continue
|
|
# Count every hit when bp is enabled
|
|
b.hits += 1
|
|
if not b.cond:
|
|
# If unconditional, and ignoring go on to next, else break
|
|
if b.ignore > 0:
|
|
b.ignore -= 1
|
|
continue
|
|
else:
|
|
# breakpoint and marker that it's ok to delete if temporary
|
|
return (b, True)
|
|
else:
|
|
# Conditional bp.
|
|
# Ignore count applies only to those bpt hits where the
|
|
# condition evaluates to true.
|
|
try:
|
|
val = eval(b.cond, frame.f_globals, frame.f_locals)
|
|
if val:
|
|
if b.ignore > 0:
|
|
b.ignore -= 1
|
|
# continue
|
|
else:
|
|
return (b, True)
|
|
# else:
|
|
# continue
|
|
except:
|
|
# if eval fails, most conservative thing is to stop on
|
|
# breakpoint regardless of ignore count. Don't delete
|
|
# temporary, as another hint to user.
|
|
return (b, False)
|
|
return (None, None)
|
|
|
|
|
|
# -------------------- testing --------------------
|
|
|
|
class Tdb(Bdb):
|
|
def user_call(self, frame, args):
|
|
name = frame.f_code.co_name
|
|
if not name: name = '???'
|
|
print('+++ call', name, args)
|
|
def user_line(self, frame):
|
|
import linecache
|
|
name = frame.f_code.co_name
|
|
if not name: name = '???'
|
|
fn = self.canonic(frame.f_code.co_filename)
|
|
line = linecache.getline(fn, frame.f_lineno, frame.f_globals)
|
|
print('+++', fn, frame.f_lineno, name, ':', line.strip())
|
|
def user_return(self, frame, retval):
|
|
print('+++ return', retval)
|
|
def user_exception(self, frame, exc_stuff):
|
|
print('+++ exception', exc_stuff)
|
|
self.set_continue()
|
|
|
|
def foo(n):
|
|
print('foo(', n, ')')
|
|
x = bar(n*10)
|
|
print('bar returned', x)
|
|
|
|
def bar(a):
|
|
print('bar(', a, ')')
|
|
return a/2
|
|
|
|
def test():
|
|
t = Tdb()
|
|
t.run('import bdb; bdb.foo(10)')
|