summaryrefslogtreecommitdiff
path: root/debugger.py
blob: 3b6e43335b0845db72a01b30a9eab2e75aa1f559 (plain)
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
"""Customized version of pdb's default debugger.

- sets up a history file
- uses ipython if available to colorize lines of code
- overrides list command to search for current block instead
  of using 5 lines of context

:copyright: 2000-2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: General Public License version 2 - http://www.gnu.org/licenses
"""
__docformat__ = "restructuredtext en"

try:
    import readline
except ImportError:
    readline = None
import os
import os.path as osp
import sys
from pdb import Pdb
from cStringIO import StringIO
import inspect

try:
    from IPython import PyColorize
except ImportError:
    def colorize(source, *args):
        """fallback colorize function"""
        return source
else:
    def colorize(source, start_lineno, curlineno):
        """"""
        parser = PyColorize.Parser()
        output = StringIO()
        parser.format(source, output)
        annotated = []
        for index, line in enumerate(output.getvalue().splitlines()):
            lineno = index + start_lineno
            if lineno == curlineno:
                annotated.append('%4s\t->\t%s' % (lineno, line))
            else:
                annotated.append('%4s\t\t%s' % (lineno, line))                
        return '\n'.join(annotated)

def getsource(obj):
    """Return the text of the source code for an object.

    The argument may be a module, class, method, function, traceback, frame,
    or code object.  The source code is returned as a single string.  An
    IOError is raised if the source code cannot be retrieved."""
    lines, lnum = inspect.getsourcelines(obj)
    return ''.join(lines), lnum


################################################################
class Debugger(Pdb):
    """custom debugger
    
    - sets up a history file
    - uses ipython if available to colorize lines of code
    - overrides list command to search for current block instead
      of using 5 lines of context
    """
    def __init__(self, tcbk):
        Pdb.__init__(self)
        self.reset()
        while tcbk.tb_next is not None:
            tcbk = tcbk.tb_next
        self._tcbk = tcbk
        self._histfile = osp.join(os.environ["HOME"], ".pdbhist")
        
    def setup_history_file(self):
        """if readline is available, read pdb history file
        """
        if readline is not None:
            try:
                readline.read_history_file(self._histfile)
            except IOError:
                pass

    def start(self):
        """starts the interactive mode"""
        self.interaction(self._tcbk.tb_frame, self._tcbk)

    def setup(self, frame, tcbk):
        """setup hook: set up history file"""
        self.setup_history_file()
        Pdb.setup(self, frame, tcbk)

    def set_quit(self):
        """quit hook: save commands in the history file"""
        if readline is not None:
            readline.write_history_file(self._histfile)
        Pdb.set_quit(self)

    def complete_p(self, text, line, begin_idx, end_idx):
        """provide variable names completion for the ``p`` command"""
        namespace = dict(self.curframe.f_globals)
        namespace.update(self.curframe.f_locals)
        if '.' in text:
            return self.attr_matches(text, namespace)
        return [varname for varname in namespace if varname.startswith(text)]


    def attr_matches(self, text, namespace):
        """implementation coming from rlcompleter.Completer.attr_matches
        Compute matches when text contains a dot.

        Assuming the text is of the form NAME.NAME....[NAME], and is
        evaluatable in self.namespace, it will be evaluated and its attributes
        (as revealed by dir()) are used as possible completions.  (For class
        instances, class members are also considered.)

        WARNING: this can still invoke arbitrary C code, if an object
        with a __getattr__ hook is evaluated.

        """
        import re
        m = re.match(r"(\w+(\.\w+)*)\.(\w*)", text)
        if not m:
            return
        expr, attr = m.group(1, 3)
        object = eval(expr, namespace)
        words = dir(object)
        if hasattr(object,'__class__'):
            words.append('__class__')
            words = words + self.get_class_members(object.__class__)
        matches = []
        n = len(attr)
        for word in words:
            if word[:n] == attr and word != "__builtins__":
                matches.append("%s.%s" % (expr, word))
        return matches
    
    def get_class_members(self, klass):
        """implementation coming from rlcompleter.get_class_members"""
        ret = dir(klass)
        if hasattr(klass,'__bases__'):
            for base in klass.__bases__:
                ret = ret + self.get_class_members(base)
        return ret
        
    ## specific / overidden commands 
    def do_list(self, arg):
        """overrides default list command to display the surrounding block
        instead of 5 lines of context
        """
        self.lastcmd = 'list'
        if not arg:
            try:
                source, start_lineno = getsource(self.curframe)
                print colorize(''.join(source), start_lineno,
                               self.curframe.f_lineno)
            except KeyboardInterrupt:
                pass
            except IOError:
                Pdb.do_list(self, arg)
        else:
            Pdb.do_list(self, arg)
    do_l = do_list

    def do_open(self, arg):
        """opens source file corresponding to the current stack level"""
        filename = self.curframe.f_code.co_filename
        lineno = self.curframe.f_lineno
        cmd = 'emacsclient --no-wait +%s %s' % (lineno, filename)
        os.system(cmd)
        
    do_o = do_open


def pm():
    """use our custom debugger"""
    dbg = Debugger(sys.last_traceback)
    dbg.start()