Lib/traceback.py

   1 # Format and print Python stack traces
   2 #
   3 # updated to take optional "file" named parameter
   4 #    by Tommy Burnette, 9/20/95
   5
   6 import linecache
   7 import string
   8 import sys
   9 import types
  10
  11 def _print(file, str='', terminator='\n'):
  12         file.write(str+terminator)
  13
  14
  15 def print_tb(tb, limit=None, file=None):
  16         if not file:
  17                 file = sys.stderr
  18         if limit is None:
  19                 if hasattr(sys, 'tracebacklimit'):
  20                         limit = sys.tracebacklimit
  21         n = 0
  22         while tb is not None and (limit is None or n < limit):
  23                 f = tb.tb_frame
  24                 lineno = tb.tb_lineno
  25                 co = f.f_code
  26                 filename = co.co_filename
  27                 name = co.co_name
  28                 _print(file,
  29                        '  File "%s", line %d, in %s' % (filename,lineno,name))
  30                 line = linecache.getline(filename, lineno)
  31                 if line: _print(file, '    ' + string.strip(line))
  32                 tb = tb.tb_next
  33                 n = n+1
  34
  35 def format_tb(tb, limit = None):
  36         list = []
  37         for filename, lineno, name, line in extract_tb(tb, limit):
  38                 item = '  File "%s", line %d, in %s\n' % (filename,lineno,name)
  39                 if line:
  40                         item = item + '    %s\n' % string.strip(line)
  41                 list.append(item)
  42         return list
  43
  44 def extract_tb(tb, limit = None):
  45         if limit is None:
  46                 if hasattr(sys, 'tracebacklimit'):
  47                         limit = sys.tracebacklimit
  48         list = []
  49         n = 0
  50         while tb is not None and (limit is None or n < limit):
  51                 f = tb.tb_frame
  52                 lineno = tb.tb_lineno
  53                 co = f.f_code
  54                 filename = co.co_filename
  55                 name = co.co_name
  56                 line = linecache.getline(filename, lineno)
  57                 if line: line = string.strip(line)
  58                 else: line = None
  59                 list.append(filename, lineno, name, line)
  60                 tb = tb.tb_next
  61                 n = n+1
  62         return list
  63
  64
  65 def print_exception(etype, value, tb, limit=None, file=None):
  66         if not file:
  67                 file = sys.stderr
  68         if tb:
  69                 _print(file, 'Traceback (innermost last):')
  70                 print_tb(tb, limit, file)
  71         lines = format_exception_only(etype, value)
  72         for line in lines[:-1]:
  73                 _print(file, line, ' ')
  74         _print(file, lines[-1], '')
  75
  76 def format_exception(etype, value, tb, limit = None):
  77         if tb:
  78                 list = ['Traceback (innermost last):\n']
  79                 list = list + format_tb(tb, limit)
  80         list = list + format_exception_only(etype, value)
  81         return list
  82
  83 def format_exception_only(etype, value):
  84         list = []
  85         if type(etype) == types.ClassType:
  86                 stype = etype.__name__
  87         else:
  88                 stype = etype
  89         if value is None:
  90                 list.append(str(stype) + '\n')
  91         else:
  92                 if etype is SyntaxError:
  93                         try:
  94                                 msg, (filename, lineno, offset, line) = value
  95                         except:
  96                                 pass
  97                         else:
  98                                 if not filename: filename = "<string>"
  99                                 list.append('  File "%s", line %d\n' %
 100                                             (filename, lineno))
 101                                 i = 0
 102                                 while i < len(line) and \
 103                                       line[i] in string.whitespace:
 104                                         i = i+1
 105                                 list.append('    %s\n' % string.strip(line))
 106                                 s = '    '
 107                                 for c in line[i:offset-1]:
 108                                         if c in string.whitespace:
 109                                                 s = s + c
 110                                         else:
 111                                                 s = s + ' '
 112                                 list.append('%s^\n' % s)
 113                                 value = msg
 114                 list.append('%s: %s\n' % (str(stype), str(value)))
 115         return list
 116
 117
 118 def print_exc(limit=None, file=None):
 119         if not file:
 120                 file = sys.stderr
 121         print_exception(sys.exc_type, sys.exc_value, sys.exc_traceback,
 122                         limit, file)
 123
 124 def print_last(limit=None, file=None):
 125         if not file:
 126                 file = sys.stderr
 127         print_exception(sys.last_type, sys.last_value, sys.last_traceback,
 128                         limit, file)