# pdb.py -- finally, a Python debugger!
# (See pdb.doc for documentation.)
import string
import sys
import linecache
import cmd
import bdb
import repr
# Interaction prompt line will separate file and call info from code
# text using value of line_prefix string. A newline and arrow may
# be to your liking. You can set it once pdb is imported using the
# command "pdb.line_prefix = '\n% '".
# line_prefix = ': ' # Use this to get the old situation back
line_prefix = '\n-> ' # Probably a better default
class Pdb(bdb.Bdb, cmd.Cmd):
def __init__(self):
bdb.Bdb.__init__(self)
cmd.Cmd.__init__(self)
self.prompt = '(Pdb) '
def reset(self):
bdb.Bdb.reset(self)
self.forget()
def forget(self):
self.lineno = None
self.stack = []
self.curindex = 0
self.curframe = None
def setup(self, f, t):
self.forget()
self.stack, self.curindex = self.get_stack(f, t)
self.curframe = self.stack[self.curindex][0]
# Override Bdb methods (except user_call, for now)
def user_line(self, frame):
# This function is called when we stop or break at this line
self.interaction(frame, None)
def user_return(self, frame, return_value):
# This function is called when a return trap is set here
frame.f_locals['__return__'] = return_value
print '--Return--'
self.interaction(frame, None)
def user_exception(self, frame, (exc_type, exc_value, exc_traceback)):
# This function is called if an exception occurs,
# but only if we are to stop at or just below this level
frame.f_locals['__exception__'] = exc_type, exc_value
if type(exc_type) == type(''):
exc_type_name = exc_type
else: exc_type_name = exc_type.__name__
print exc_type_name + ':', repr.repr(exc_value)
self.interaction(frame, exc_traceback)
# General interaction function
def interaction(self, frame, traceback):
self.setup(frame, traceback)
self.print_stack_entry(self.stack[self.curindex])
self.cmdloop()
self.forget()
def default(self, line):
if line[:1] == '!': line = line[1:]
locals = self.curframe.f_locals
globals = self.curframe.f_globals
globals['__privileged__'] = 1
code = compile(line + '\n', '<stdin>', 'single')
try:
exec code in globals, locals
except:
if type(sys.exc_type) == type(''):
exc_type_name = sys.exc_type
else: exc_type_name = sys.exc_type.__name__
print '***', exc_type_name + ':', sys.exc_value
# Command definitions, called by cmdloop()
# The argument is the remaining string on the command line
# Return true to exit from the command loop
do_h = cmd.Cmd.do_help
def do_break(self, arg):
if not arg:
print self.get_all_breaks() # XXX
return
# Try line number as argument
try:
lineno = int(eval(arg))
filename = self.curframe.f_code.co_filename
except:
# Try function name as the argument
import codehack
try:
func = eval(arg, self.curframe.f_globals,
self.curframe.f_locals)
if hasattr(func, 'im_func'):
func = func.im_func
code = func.func_code
except:
print '*** Could not eval argument:', arg
return
lineno = codehack.getlineno(code)
filename = code.co_filename
# now set the break point
err = self.set_break(filename, lineno)
if err: print '***', err
do_b = do_break
def do_clear(self, arg):
if not arg:
try:
reply = raw_input('Clear all breaks? ')
except EOFError:
reply = 'no'
reply = string.lower(string.strip(reply))
if reply in ('y', 'yes'):
self.clear_all_breaks()
return
try:
lineno = int(eval(arg))
except:
print '*** Error in argument:', `arg`
return
filename = self.curframe.f_code.co_filename
err = self.clear_break(filename, lineno)
if err: print '***', err
do_cl = do_clear # 'c' is already an abbreviation for 'continue'
def do_where(self, arg):
self.print_stack_trace()
do_w = do_where
def do_up(self, arg):
if self.curindex == 0:
print '*** Oldest frame'
else:
self.curindex = self.curindex - 1
self.curframe = self.stack[self.curindex][0]
self.print_stack_entry(self.stack[self.curindex])
self.lineno = None
do_u = do_up
def do_down(self, arg):
if self.curindex + 1 == len(self.stack):
print '*** Newest frame'
else:
self.curindex = self.curindex + 1
self.curframe = self.stack[self.curindex][0]
self.print_stack_entry(self.stack[self.curindex])
self.lineno = None
do_d = do_down
def do_step(self, arg):
self.set_step()
return 1
do_s = do_step
def do_next(self, arg):
self.set_next(self.curframe)
return 1
do_n = do_next
def do_return(self, arg):
self.set_return(self.curframe)
return 1
do_r = do_return
def do_continue(self, arg):
self.set_continue()
return 1
do_c = do_cont = do_continue
def do_quit(self, arg):
self.set_quit()
return 1
do_q = do_quit
def do_args(self, arg):
if self.curframe.f_locals.has_key('__args__'):
print `self.curframe.f_locals['__args__']`
else:
print '*** No arguments?!'
do_a = do_args
def do_retval(self, arg):
if self.curframe.f_locals.has_key('__return__'):
print self.curframe.f_locals['__return__']
else:
print '*** Not yet returned!'
do_rv = do_retval
def do_p(self, arg):
self.curframe.f_globals['__privileged__'] = 1
try:
value = eval(arg, self.curframe.f_globals, \
self.curframe.f_locals)
except:
if type(sys.exc_type) == type(''):
exc_type_name = sys.exc_type
else: exc_type_name = sys.exc_type.__name__
print '***', exc_type_name + ':', `sys.exc_value`
return
print `value`
def do_list(self, arg):
self.lastcmd = 'list'
last = None
if arg:
try:
x = eval(arg, {}, {})
if type(x) == type(()):
first, last = x
first = int(first)
last = int(last)
if last < first:
# Assume it's a count
last = first + last
else:
first = max(1, int(x) - 5)
except:
print '*** Error in argument:', `arg`
return
elif self.lineno is None:
first = max(1, self.curframe.f_lineno - 5)
else:
first = self.lineno + 1
if last == None:
last = first + 10
filename = self.curframe.f_code.co_filename
breaklist = self.get_file_breaks(filename)
try:
for lineno in range(first, last+1):
line = linecache.getline(filename, lineno)
if not line:
print '[EOF]'
break
else:
s = string.rjust(`lineno`, 3)
if len(s) < 4: s = s + ' '
if lineno in breaklist: s = s + 'B'
else: s = s + ' '
if lineno == self.curframe.f_lineno:
s = s + '->'
print s + '\t' + line,
self.lineno = lineno
except KeyboardInterrupt:
pass
do_l = do_list
def do_whatis(self, arg):
try:
value = eval(arg, self.curframe.f_globals, \
self.curframe.f_locals)
except:
if type(sys.exc_type) == type(''):
exc_type_name = sys.exc_type
else: exc_type_name = sys.exc_type.__name__
print '***', exc_type_name + ':', `sys.exc_value`
return
code = None
# Is it a function?
try: code = value.func_code
except: pass
if code:
print 'Function', code.co_name
return
# Is it an instance method?
try: code = value.im_func.func_code
except: pass
if code:
print 'Method', code.co_name
return
# None of the above...
print type(value)
# Print a traceback starting at the top stack frame.
# The most recently entered frame is printed last;
# this is different from dbx and gdb, but consistent with
# the Python interpreter's stack trace.
# It is also consistent with the up/down commands (which are
# compatible with dbx and gdb: up moves towards 'main()'
# and down moves towards the most recent stack frame).
def print_stack_trace(self):
try:
for frame_lineno in self.stack:
self.print_stack_entry(frame_lineno)
except KeyboardInterrupt:
pass
def print_stack_entry(self, frame_lineno, prompt_prefix=line_prefix):
frame, lineno = frame_lineno
if frame is self.curframe:
print '>',
else:
print ' ',
print self.format_stack_entry(frame_lineno, prompt_prefix)
# Help methods (derived from pdb.doc)
def help_help(self):
self.help_h()
def help_h(self):
print """h(elp)
Without argument, print the list of available commands.
With a command name as argument, print help about that command
"help pdb" pipes the full documentation file to the $PAGER
"help exec" gives help on the ! command"""
def help_where(self):
self.help_w()
def help_w(self):
print """w(here)
Print a stack trace, with the most recent frame at the bottom.
An arrow indicates the "current frame", which determines the
context of most commands."""
def help_down(self):
self.help_d()
def help_d(self):
print """d(own)
Move the current frame one level down in the stack trace
(to an older frame)."""
def help_up(self):
self.help_u()
def help_u(self):
print """u(p)
Move the current frame one level up in the stack trace
(to a newer frame)."""
def help_break(self):
self.help_b()
def help_b(self):
print """b(reak) [lineno | function]
With a line number argument, set a break there in the current
file. With a function name, set a break at the entry of that
function. Without argument, list all breaks."""
def help_clear(self):
self.help_cl()
def help_cl(self):
print """cl(ear) [lineno]
With a line number argument, clear that break in the current file.
Without argument, clear all breaks (but first ask confirmation)."""
def help_step(self):
self.help_s()
def help_s(self):
print """s(tep)
Execute the current line, stop at the first possible occasion
(either in a function that is called or in the current function)."""
def help_next(self):
self.help_n()
def help_n(self):
print """n(ext)
Continue execution until the next line in the current function
is reached or it returns."""
def help_return(self):
self.help_r()
def help_r(self):
print """r(eturn)
Continue execution until the current function returns."""
def help_continue(self):
self.help_c()
def help_cont(self):
self.help_c()
def help_c(self):
print """c(ont(inue))
Continue execution, only stop when a breakpoint is encountered."""
def help_list(self):
self.help_l()
def help_l(self):
print """l(ist) [first [,last]]
List source code for the current file.
Without arguments, list 11 lines around the current line
or continue the previous listing.
With one argument, list 11 lines starting at that line.
With two arguments, list the given range;
if the second argument is less than the first, it is a count."""
def help_args(self):
self.help_a()
def help_a(self):
print """a(rgs)
Print the argument list of the current function."""
def help_p(self):
print """p expression
Print the value of the expression."""
def help_exec(self):
print """(!) statement
Execute the (one-line) statement in the context of
the current stack frame.
The exclamation point can be omitted unless the first word
of the statement resembles a debugger command.
To assign to a global variable you must always prefix the
command with a 'global' command, e.g.:
(Pdb) global list_options; list_options = ['-l']
(Pdb)"""
def help_quit(self):
self.help_q()
def help_q(self):
print """q(uit) Quit from the debugger.
The program being executed is aborted."""
def help_pdb(self):
help()
# Simplified interface
def run(statement, globals=None, locals=None):
Pdb().run(statement, globals, locals)
def runeval(expression, globals=None, locals=None):
return Pdb().runeval(expression, globals, locals)
def runctx(statement, globals, locals):
# B/W compatibility
run(statement, globals, locals)
def runcall(*args):
return apply(Pdb().runcall, args)
def set_trace():
Pdb().set_trace()
# Post-Mortem interface
def post_mortem(t):
p = Pdb()
p.reset()
while t.tb_next <> None: t = t.tb_next
p.interaction(t.tb_frame, t)
def pm():
import sys
post_mortem(sys.last_traceback)
# Main program for testing
TESTCMD = 'import x; x.main()'
def test():
run(TESTCMD)
# print help
def help():
import os
for dirname in sys.path:
fullname = os.path.join(dirname, 'pdb.doc')
if os.path.exists(fullname):
sts = os.system('${PAGER-more} '+fullname)
if sts: print '*** Pager exit status:', sts
break
else:
print 'Sorry, can\'t find the help file "pdb.doc"',
print 'along the Python search path'