1. David Wolever
  2. dotfiles

Source

dotfiles / python / pdb.py

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
"""
Pdb++, a fancier version of pdb
===============================

This module extends the stdlib pdb in numerous ways, e.g. by providing
real completion of Python values instead of pdb's own commands, or by
adding few convenience commands like ``longlist``, ``interact`` or
``watch``.

For a full explanation of each command, refer to the docstring or type
help <command> at the prompt.

Installation
------------

This module is meant to replace stdlib's pdb.py from the outsite;
simply put it in a directory in your PYTHONPATH, and you can start
using it immediately.  Since it's named pdb.py, every place which
imports pdb will now find the new module.

Dependencies
------------

To work properly, this module needs `rlcompleter_ng`_ to be installed.

To enable syntax highlighting, you must install `pygments`.

.. _pygments: http://pygments.org/
.. _`rlcompleter_ng`: http://codespeak.net/svn/user/antocuni/hack/rlcompleter_ng.py

Configuration
-------------

To customize the configuration of Pdb++, you need to put a file named
.pdbrc.py in your home directory.  The file must contain a class named
``Config`` inheriting from ``DefaultConfig`` and overridding the
desired values.

To know which options are available, look at the comment in the
source.

You can find a sample configuration file, here:
http://codespeak.net/svn/user/antocuni/hack/pdbrc.py
"""

__version__='0.1'
__author__ ='Antonio Cuni <anto.cuni@gmail.com>'
__url__='http://codespeak.net/svn/user/antocuni/hack/pdb.py'

import sys
import os.path
import inspect
import code
import types
import traceback
import subprocess
import re
from rlcompleter_ng import Completer, ConfigurableClass, setcolor, colors

# if it contains only _, digits, letters, [] or dots, it's probably side effects
# free
side_effects_free = re.compile(r'^ *[_0-9a-zA-Z\[\].]* *$')

def import_from_stdlib(name):
    import code # arbitrary module which stays in the same dir as pdb
    stdlibdir, _ = os.path.split(code.__file__)
    pyfile = os.path.join(stdlibdir, name + '.py')
    result = types.ModuleType(name)
    mydict = execfile(pyfile, result.__dict__)
    return result

pdb = import_from_stdlib('pdb')


class DefaultConfig:
    prompt = '(Pdb++) '
    completekey = 'tab'
    highlight = True
    bg = 'dark'
    colorscheme = None
    editor = '${EDITOR:-vi}' # use $EDITOR if set, else default to vi
    stdin_paste = None       # for emacs, you can use my bin/epaste script
    truncate_long_lines = True
    ring_if_not_active = False

    line_number_color = colors.turquoise
    current_line_color = 44 # blue

    def setup(self, pdb):
        pass

def getsourcelines(obj):
    try:
        return inspect.getsourcelines(obj)
    except IOError:
        pass

    if isinstance(obj, types.FrameType):
        filename = obj.f_code.co_filename
        if hasattr(filename, '__source__'):
            first = max(1, obj.f_lineno - 5)
            lines = [line + '\n' for line in filename.__source__.lines]
            return lines, first
    raise IOError('could not get source code')

def setbgcolor(line, color):
    # hack hack hack
    # add a bgcolor attribute to all escape sequences found
    import re
    setbg = '\x1b[%dm' % color
    regexbg = '\\1;%dm' % color
    return setbg + re.sub('(\x1b\\[.*?)m', regexbg, line) + '\x1b[00m'

CLEARSCREEN = '\033[2J\033[1;1H'

def lasti2lineno(code, lasti):
    import dis
    linestarts = list(dis.findlinestarts(code))
    linestarts.reverse()
    for i, lineno in linestarts:
        if lasti >= i:
            return lineno
    return 0

class Undefined:
    def __repr__(self):
        return '<undefined>'
undefined = Undefined()

class Pdb(pdb.Pdb, ConfigurableClass):

    DefaultConfig = DefaultConfig
    config_filename = '.pdbrc.py'

    def __init__(self, *args, **kwds):
        Config = kwds.pop('Config', None)
        self.start_lineno = kwds.pop('start_lineno', None)
        self.start_filename = kwds.pop('start_filename', None)
        pdb.Pdb.__init__(self, *args, **kwds)
        self.config = self.get_config(Config)
        self.config.setup(self)
        self.prompt = self.config.prompt
        self.completekey = self.config.completekey

        self.mycompleter = None
        self.watching = {} # frame --> (name --> last seen value)
        self.sticky = False
        self.sticky_ranges = {} # frame --> (start, end)
        self.tb_lineno = {} # frame --> lineno where the exception raised
        self.history = []

    def interaction(self, frame, traceback):
        if self.config.ring_if_not_active:
            self.ring_if_not_active()
        self.setup(frame, traceback)
        self.print_stack_entry(self.stack[self.curindex])
        self.cmdloop()
        self.forget()

    def ring_if_not_active(self):
        import os
        import wmctrl
        try:
            winid = int(os.getenv('WINDOWID'))
        except (TypeError, ValueError):
            return # cannot find WINDOWID of the terminal
        active_win = wmctrl.get_active_window()
        if not active_win or (int(active_win.id, 16) != winid):
            os.system("playsound /usr/share/sounds/ekiga/dialtone.wav > /dev/null &")

    def setup(self, frame, tb):
        pdb.Pdb.setup(self, frame, tb)
        while tb:
            lineno = lasti2lineno(tb.tb_frame.f_code, tb.tb_lasti)
            self.tb_lineno[tb.tb_frame] = lineno
            tb = tb.tb_next

    def get_stack(self, f, t):
        # Modified from bdb.py to be able to walk the stack beyond generators,
        # which does not work in the normal pdb :-(
        stack, i = pdb.Pdb.get_stack(self, f, t)
        if f is None:
            i = max(0, len(stack) - 1)
        return stack, i

    def forget(self):
        pdb.Pdb.forget(self)
        self.raise_lineno = {}

    def complete(self, text, state):
        if state == 0:
            mydict = self.curframe.f_globals.copy()
            mydict.update(self.curframe.f_locals)
            self.mycompleter = Completer(mydict)
        return self.mycompleter.complete(text, state)

    def _init_pygments(self): 
        try:
            from pygments.lexers import PythonLexer
            from pygments.formatters import TerminalFormatter
        except ImportError:
            return False

        if hasattr(self, '_fmt'):
            return True
        
        self._fmt = TerminalFormatter(bg=self.config.bg,
                                      colorscheme=self.config.colorscheme)
        self._lexer = PythonLexer()
        return True

    def format_source(self, src):
        if not self._init_pygments():
            return src
        from pygments import highlight, lex
        return highlight(src, self._lexer, self._fmt)

    def format_line(self, lineno, marker, line):
        lineno = '%4d' % lineno
        if self.config.highlight:
            lineno = setcolor(lineno, self.config.line_number_color)
        line = '%s  %2s %s' % (lineno, marker, line)
        if self.config.highlight and marker == '->':
            line = setbgcolor(line, self.config.current_line_color)
        return line

    def parseline(self, line):
        cmd, arg, newline = pdb.Pdb.parseline(self, line)
        # don't execute short disruptive commands if a variable with
        # the name exits in the current contex; this prevents pdb to
        # quit if you type e.g. 'r[0]' by mystake.
        if cmd in ['c', 'r', 'q', 'args'] and (cmd in self.curframe.f_globals or
                                               cmd in self.curframe.f_locals):
            line = '!' + line
            return pdb.Pdb.parseline(self, line)
        return cmd, arg, newline

    def default(self, line):
        self.history.append(line)
        return pdb.Pdb.default(self, line)

    def do_longlist(self, arg):
        """
        {longlist|ll}
        List source code for the current function.
        
        Differently that list, the whole function is displayed; the
        current line is marked with '->'.  In case of post-mortem
        debugging, the line which effectively raised the exception is
        marked with '>>'.

        If the 'highlight' config option is set and pygments is
        installed, the source code is colorized.
        """
        self.lastcmd = 'longlist'
        self._printlonglist()

    def _printlonglist(self, linerange=None):
        try:
            lines, lineno = getsourcelines(self.curframe)
        except IOError, e:
            print '** Error: %s **' % e
            return
        if linerange:
            start, end = linerange
            start = max(start, lineno)
            end = min(end, lineno+len(lines))
            lines = lines[start-lineno:end-lineno]
            lineno = start
        self._print_lines(lines, lineno)

    def _print_lines(self, lines, lineno, print_markers=True):
        exc_lineno = self.tb_lineno.get(self.curframe, None)
        lines = [line[:-1] for line in lines] # remove the trailing '\n'
        width, height = self.get_terminal_size()

        if self.config.truncate_long_lines:
            maxlength = max(width - 9, 16)
            lines = [line[:maxlength] for line in lines]
        else:
            maxlength = max(map(len, lines))

        if self.config.highlight:
            lines = [line.ljust(maxlength) for line in lines]
            src = self.format_source('\n'.join(lines))
            lines = src.splitlines()
        if height >= 6:
            last_marker_line = max(self.curframe.f_lineno, exc_lineno) - lineno
            if last_marker_line >= 0:
                maxlines = last_marker_line + height * 2 // 3
                if len(lines) > maxlines:
                    lines = lines[:maxlines]
                    lines.append('...')
        for i, line in enumerate(lines):
            marker = ''
            if lineno == self.curframe.f_lineno and print_markers:
                marker = '->'
            elif lineno == exc_lineno and print_markers:
                marker = '>>'
            lines[i] = self.format_line(lineno, marker, line)
            lineno += 1
        print '\n'.join(lines)

    do_ll = do_longlist

    def do_list(self, arg):
        from StringIO import StringIO
        oldstdout = sys.stdout
        sys.stdout = StringIO()
        pdb.Pdb.do_list(self, arg)
        src = self.format_source(sys.stdout.getvalue())
        sys.stdout = oldstdout
        print src,

    do_l = do_list

    def do_interact(self, arg):
        """
        interact

        Start an interative interpreter whose global namespace
        contains all the names found in the current scope.
        """
        ns = self.curframe.f_globals.copy()
        ns.update(self.curframe.f_locals)
        code.interact("*interactive*", local=ns)

    def do_track(self, arg):
        """
        track expression

        Display a graph showing which objects are referred by the
        value of the expression.  This command requires pypy to be in
        the current PYTHONPATH.
        """
        try:
            from pypy.translator.tool.reftracker import track
        except ImportError:
            print '** cannot import pypy.translator.tool.reftracker **'
            return
        val = self._getval(arg)
        track(val)

    def _get_watching(self):
        return self.watching.setdefault(self.curframe, {})

    def _getval_or_undefined(self, arg):
        try:
            return eval(arg, self.curframe.f_globals,
                        self.curframe.f_locals)
        except NameError:
            return undefined

    def do_watch(self, arg):
        """
        watch expression

        Add expression to the watching list; expressions in this list
        are evaluated at each step, and printed every time its value
        changes.

        WARNING: since the expressions is evaluated multiple time, pay
        attention not to put expressions with side-effects in the
        watching list.
        """
        try:
            value = self._getval_or_undefined(arg)
        except:
            return
        self._get_watching()[arg] = value

    def do_unwatch(self, arg):
        """
        unwatch expression

        Remove expression from the watching list.
        """
        try:
            del self._get_watching()[arg]
        except KeyError:
            print '** not watching %s **' % arg

    def _print_if_sticky(self):
        if self.sticky:
            sys.stdout.write(CLEARSCREEN)
            frame, lineno = self.stack[self.curindex]
            filename = self.canonic(frame.f_code.co_filename)
            s = '> %s(%r)' % (filename, lineno)
            print s
            print
            sticky_range = self.sticky_ranges.get(self.curframe, None)
            self._printlonglist(sticky_range)

            if '__exception__' in frame.f_locals:
                exc = frame.f_locals['__exception__']
                if len(exc) == 2:
                    exc_type, exc_value = exc
                    s = ''
                    try:
                        try:
                            s = exc_type.__name__
                        except AttributeError:
                            s = str(exc_type)
                        if exc_value is not None:
                            s += ': '
                            s += str(exc_value)
                    except KeyboardInterrupt:
                        raise
                    except:
                        s += '(unprintable exception)'
                    print setcolor(' ' + s, self.config.line_number_color)
                    return
            if '__return__' in frame.f_locals:
                rv = frame.f_locals['__return__']
                try:
                    s = repr(rv)
                except KeyboardInterrupt:
                    raise
                except:
                    s = '(unprintable return value)'
                print setcolor(' return ' + s, self.config.line_number_color)

    def do_sticky(self, arg):
        """
        sticky [start end]

        Toggle sticky mode. When in sticky mode, it clear the screen
        and longlist the current functions, making the source
        appearing always in the same position. Useful to follow the
        flow control of a function when doing step-by-step execution.

        If ``start`` and ``end`` are given, sticky mode is enabled and
        only lines within that range (extremes included) will be
        displayed.
        """
        if arg:
            try:
                start, end = map(int, arg.split())
            except ValueError:
                print '** Error when parsing argument: %s **' % arg
                return
            self.sticky = True
            self.sticky_ranges[self.curframe] = start, end+1
        else:
            self.sticky = not self.sticky
            self.sticky_range = None
        self._print_if_sticky()

    def print_current_stack_entry(self):
        if self.sticky:
            self._print_if_sticky()
        else:
            self.print_stack_entry(self.stack[self.curindex])

    def preloop(self):
        self._print_if_sticky()
        watching = self._get_watching()
        for expr, oldvalue in watching.iteritems():
            newvalue = self._getval_or_undefined(expr)
            # check for identity first; this prevents custom __eq__ to
            # be called at every loop, and also prevents instances
            # whose fields are changed to be displayed
            if newvalue is not oldvalue or newvalue != oldvalue:
                watching[expr] = newvalue
                print '%s: %r --> %r' % (expr, oldvalue, newvalue)

    def do_source(self, arg):
        try:
            obj = self._getval(arg)
        except:
            return
        try:
            lines, lineno = getsourcelines(obj)
        except (IOError, TypeError), e:
            print '** Error: %s **' % e
            return
        self._print_lines(lines, lineno, print_markers=False)

    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_current_stack_entry()
            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_current_stack_entry()
            self.lineno = None
    do_d = do_down

    def get_terminal_size(self):
        try:
            import termios, fcntl, struct
            call = fcntl.ioctl(0, termios.TIOCGWINSZ, "\x00"*8)
            height, width = struct.unpack("hhhh", call)[:2]
        except (SystemExit, KeyboardInterrupt), e:
            raise
        except:
            width = int(os.environ.get('COLUMNS', 80))
            height = int(os.environ.get('COLUMNS', 24))
        return width, height

    def _open_editor(self, editor, lineno, filename):
        os.system("%s +%d '%s'" % (editor, lineno, filename))
    
    def do_edit(self, arg):
        "Open an editor visiting the current file at the current line"
        editor = self.config.editor
        frame = self.curframe
        lineno = frame.f_lineno
        filename = os.path.abspath(frame.f_code.co_filename)
        filename = filename.replace("'", "\\'")
        self._open_editor(editor, lineno, filename)

    do_ed = do_edit

    def _get_history(self):
        return [s for s in self.history if not side_effects_free.match(s)]

    def _get_history_text(self):
        import linecache
        line = linecache.getline(self.start_filename, self.start_lineno)
        nspaces = len(line) - len(line.lstrip())
        indent = ' ' * nspaces
        history = [indent + s for s in self._get_history()]
        return '\n'.join(history) + '\n'

    def _open_stdin_paste(self, stdin_paste, lineno, filename, text):
        proc = subprocess.Popen([stdin_paste, '+%d' % lineno, filename],
                                stdin = subprocess.PIPE)
        proc.stdin.write(text)
        proc.stdin.close()

    def do_put(self, arg):
        stdin_paste = self.config.stdin_paste
        if stdin_paste is None:
            print '** Error: the "stdin_paste" option is not configure **'
        filename = self.start_filename
        lineno = self.start_lineno
        text = self._get_history_text()
        self._open_stdin_paste(stdin_paste, lineno, filename, text)


# simplified interface

# copy some functions from pdb.py, but rebind the global dictionary
for name in 'run runeval runctx runcall pm main'.split():
    func = getattr(pdb, name)
    newfunc = types.FunctionType(func.func_code, globals(), func.func_name)
    globals()[name] = newfunc
del name, func, newfunc

def post_mortem(t, Pdb=Pdb):
    p = Pdb()
    p.reset()
    p.interaction(None, t)

def set_trace(frame=None, Pdb=Pdb):
    if frame is None:
        frame = sys._getframe().f_back
    filename = frame.f_code.co_filename
    lineno = frame.f_lineno
    Pdb(start_lineno=lineno, start_filename=filename).set_trace(frame)

# pdb++ specific interface

def xpm(Pdb=Pdb):
    """
    To be used inside an except clause, enter a post-mortem pdb
    related to the just catched exception.
    """
    post_mortem(sys.exc_info()[2], Pdb)

def set_tracex():
    print 'PDB!'
set_tracex._dont_inline_ = True

if __name__=='__main__':
    main()