Guido van Rossum | e7b146f | 2000-02-04 15:28:42 +0000 | [diff] [blame] | 1 | """Extract, format and print information about Python stack traces.""" |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 2 | |
| 3 | import linecache |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 4 | import sys |
Guido van Rossum | c7acf2a | 1995-02-27 13:15:45 +0000 | [diff] [blame] | 5 | import types |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 6 | |
Skip Montanaro | 40fc160 | 2001-03-01 04:27:19 +0000 | [diff] [blame] | 7 | __all__ = ['extract_stack', 'extract_tb', 'format_exception', |
| 8 | 'format_exception_only', 'format_list', 'format_stack', |
Neil Schemenauer | f607fc5 | 2003-11-05 23:03:00 +0000 | [diff] [blame] | 9 | 'format_tb', 'print_exc', 'format_exc', 'print_exception', |
| 10 | 'print_last', 'print_stack', 'print_tb', 'tb_lineno'] |
Skip Montanaro | 40fc160 | 2001-03-01 04:27:19 +0000 | [diff] [blame] | 11 | |
Guido van Rossum | 194e20a | 1995-09-20 20:31:51 +0000 | [diff] [blame] | 12 | def _print(file, str='', terminator='\n'): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 13 | file.write(str+terminator) |
Guido van Rossum | dcc057a | 1996-08-12 23:18:13 +0000 | [diff] [blame] | 14 | |
| 15 | |
| 16 | def print_list(extracted_list, file=None): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 17 | """Print the list of tuples as returned by extract_tb() or |
| 18 | extract_stack() as a formatted stack trace to the given file.""" |
Raymond Hettinger | 10ff706 | 2002-06-02 03:04:52 +0000 | [diff] [blame] | 19 | if file is None: |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 20 | file = sys.stderr |
| 21 | for filename, lineno, name, line in extracted_list: |
| 22 | _print(file, |
| 23 | ' File "%s", line %d, in %s' % (filename,lineno,name)) |
| 24 | if line: |
Eric S. Raymond | ec3bbde | 2001-02-09 09:39:08 +0000 | [diff] [blame] | 25 | _print(file, ' %s' % line.strip()) |
Guido van Rossum | dcc057a | 1996-08-12 23:18:13 +0000 | [diff] [blame] | 26 | |
| 27 | def format_list(extracted_list): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 28 | """Format a list of traceback entry tuples for printing. |
| 29 | |
| 30 | Given a list of tuples as returned by extract_tb() or |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 31 | extract_stack(), return a list of strings ready for printing. |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 32 | Each string in the resulting list corresponds to the item with the |
| 33 | same index in the argument list. Each string ends in a newline; |
| 34 | the strings may contain internal newlines as well, for those items |
| 35 | whose source text line is not None. |
| 36 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 37 | list = [] |
| 38 | for filename, lineno, name, line in extracted_list: |
| 39 | item = ' File "%s", line %d, in %s\n' % (filename,lineno,name) |
| 40 | if line: |
Eric S. Raymond | ec3bbde | 2001-02-09 09:39:08 +0000 | [diff] [blame] | 41 | item = item + ' %s\n' % line.strip() |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 42 | list.append(item) |
| 43 | return list |
| 44 | |
Guido van Rossum | 194e20a | 1995-09-20 20:31:51 +0000 | [diff] [blame] | 45 | |
| 46 | def print_tb(tb, limit=None, file=None): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 47 | """Print up to 'limit' stack trace entries from the traceback 'tb'. |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 48 | |
| 49 | If 'limit' is omitted or None, all entries are printed. If 'file' |
| 50 | is omitted or None, the output goes to sys.stderr; otherwise |
| 51 | 'file' should be an open file or file-like object with a write() |
| 52 | method. |
| 53 | """ |
Raymond Hettinger | 10ff706 | 2002-06-02 03:04:52 +0000 | [diff] [blame] | 54 | if file is None: |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 55 | file = sys.stderr |
| 56 | if limit is None: |
| 57 | if hasattr(sys, 'tracebacklimit'): |
| 58 | limit = sys.tracebacklimit |
| 59 | n = 0 |
| 60 | while tb is not None and (limit is None or n < limit): |
| 61 | f = tb.tb_frame |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 62 | lineno = tb.tb_lineno |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 63 | co = f.f_code |
| 64 | filename = co.co_filename |
| 65 | name = co.co_name |
| 66 | _print(file, |
| 67 | ' File "%s", line %d, in %s' % (filename,lineno,name)) |
Hye-Shik Chang | 182ac85 | 2004-10-26 09:16:42 +0000 | [diff] [blame] | 68 | linecache.checkcache(filename) |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 69 | line = linecache.getline(filename, lineno) |
Eric S. Raymond | ec3bbde | 2001-02-09 09:39:08 +0000 | [diff] [blame] | 70 | if line: _print(file, ' ' + line.strip()) |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 71 | tb = tb.tb_next |
| 72 | n = n+1 |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 73 | |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 74 | def format_tb(tb, limit = None): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 75 | """A shorthand for 'format_list(extract_stack(f, limit)).""" |
| 76 | return format_list(extract_tb(tb, limit)) |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 77 | |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 78 | def extract_tb(tb, limit = None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 79 | """Return list of up to limit pre-processed entries from traceback. |
| 80 | |
| 81 | This is useful for alternate formatting of stack traces. If |
| 82 | 'limit' is omitted or None, all entries are extracted. A |
| 83 | pre-processed stack trace entry is a quadruple (filename, line |
| 84 | number, function name, text) representing the information that is |
| 85 | usually printed for a stack trace. The text is a string with |
| 86 | leading and trailing whitespace stripped; if the source is not |
| 87 | available it is None. |
| 88 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 89 | if limit is None: |
| 90 | if hasattr(sys, 'tracebacklimit'): |
| 91 | limit = sys.tracebacklimit |
| 92 | list = [] |
| 93 | n = 0 |
| 94 | while tb is not None and (limit is None or n < limit): |
| 95 | f = tb.tb_frame |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 96 | lineno = tb.tb_lineno |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 97 | co = f.f_code |
| 98 | filename = co.co_filename |
| 99 | name = co.co_name |
Hye-Shik Chang | 182ac85 | 2004-10-26 09:16:42 +0000 | [diff] [blame] | 100 | linecache.checkcache(filename) |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 101 | line = linecache.getline(filename, lineno) |
Eric S. Raymond | ec3bbde | 2001-02-09 09:39:08 +0000 | [diff] [blame] | 102 | if line: line = line.strip() |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 103 | else: line = None |
| 104 | list.append((filename, lineno, name, line)) |
| 105 | tb = tb.tb_next |
| 106 | n = n+1 |
| 107 | return list |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 108 | |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 109 | |
Guido van Rossum | 194e20a | 1995-09-20 20:31:51 +0000 | [diff] [blame] | 110 | def print_exception(etype, value, tb, limit=None, file=None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 111 | """Print exception up to 'limit' stack trace entries from 'tb' to 'file'. |
| 112 | |
| 113 | This differs from print_tb() in the following ways: (1) if |
| 114 | traceback is not None, it prints a header "Traceback (most recent |
| 115 | call last):"; (2) it prints the exception type and value after the |
| 116 | stack trace; (3) if type is SyntaxError and value has the |
| 117 | appropriate format, it prints the line where the syntax error |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 118 | occurred with a caret on the next line indicating the approximate |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 119 | position of the error. |
| 120 | """ |
Raymond Hettinger | 10ff706 | 2002-06-02 03:04:52 +0000 | [diff] [blame] | 121 | if file is None: |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 122 | file = sys.stderr |
| 123 | if tb: |
| 124 | _print(file, 'Traceback (most recent call last):') |
| 125 | print_tb(tb, limit, file) |
| 126 | lines = format_exception_only(etype, value) |
| 127 | for line in lines[:-1]: |
| 128 | _print(file, line, ' ') |
| 129 | _print(file, lines[-1], '') |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 130 | |
| 131 | def format_exception(etype, value, tb, limit = None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 132 | """Format a stack trace and the exception information. |
| 133 | |
| 134 | The arguments have the same meaning as the corresponding arguments |
| 135 | to print_exception(). The return value is a list of strings, each |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 136 | ending in a newline and some containing internal newlines. When |
| 137 | these lines are concatenated and printed, exactly the same text is |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 138 | printed as does print_exception(). |
| 139 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 140 | if tb: |
| 141 | list = ['Traceback (most recent call last):\n'] |
| 142 | list = list + format_tb(tb, limit) |
| 143 | else: |
| 144 | list = [] |
| 145 | list = list + format_exception_only(etype, value) |
| 146 | return list |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 147 | |
| 148 | def format_exception_only(etype, value): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 149 | """Format the exception part of a traceback. |
| 150 | |
| 151 | The arguments are the exception type and value such as given by |
| 152 | sys.last_type and sys.last_value. The return value is a list of |
| 153 | strings, each ending in a newline. Normally, the list contains a |
| 154 | single string; however, for SyntaxError exceptions, it contains |
| 155 | several lines that (when printed) display detailed information |
| 156 | about where the syntax error occurred. The message indicating |
| 157 | which exception occurred is the always last string in the list. |
| 158 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 159 | list = [] |
Brett Cannon | bf36409 | 2006-03-01 04:25:17 +0000 | [diff] [blame] | 160 | if (type(etype) == types.ClassType |
Thomas Wouters | 7c187bc | 2006-03-01 05:34:22 +0000 | [diff] [blame] | 161 | or issubclass(etype, Exception)): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 162 | stype = etype.__name__ |
| 163 | else: |
| 164 | stype = etype |
| 165 | if value is None: |
| 166 | list.append(str(stype) + '\n') |
| 167 | else: |
| 168 | if etype is SyntaxError: |
| 169 | try: |
| 170 | msg, (filename, lineno, offset, line) = value |
| 171 | except: |
| 172 | pass |
| 173 | else: |
| 174 | if not filename: filename = "<string>" |
| 175 | list.append(' File "%s", line %d\n' % |
| 176 | (filename, lineno)) |
Tim Peters | 0bb580d | 2001-06-10 18:58:26 +0000 | [diff] [blame] | 177 | if line is not None: |
| 178 | i = 0 |
| 179 | while i < len(line) and line[i].isspace(): |
| 180 | i = i+1 |
| 181 | list.append(' %s\n' % line.strip()) |
| 182 | if offset is not None: |
| 183 | s = ' ' |
| 184 | for c in line[i:offset-1]: |
| 185 | if c.isspace(): |
| 186 | s = s + c |
| 187 | else: |
| 188 | s = s + ' ' |
| 189 | list.append('%s^\n' % s) |
| 190 | value = msg |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 191 | s = _some_str(value) |
| 192 | if s: |
| 193 | list.append('%s: %s\n' % (str(stype), s)) |
| 194 | else: |
| 195 | list.append('%s\n' % str(stype)) |
| 196 | return list |
Guido van Rossum | 28e99fe | 1995-08-04 04:30:30 +0000 | [diff] [blame] | 197 | |
Guido van Rossum | 2823f03 | 2000-08-22 02:04:46 +0000 | [diff] [blame] | 198 | def _some_str(value): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 199 | try: |
| 200 | return str(value) |
| 201 | except: |
| 202 | return '<unprintable %s object>' % type(value).__name__ |
Guido van Rossum | 2823f03 | 2000-08-22 02:04:46 +0000 | [diff] [blame] | 203 | |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 204 | |
Guido van Rossum | 194e20a | 1995-09-20 20:31:51 +0000 | [diff] [blame] | 205 | def print_exc(limit=None, file=None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 206 | """Shorthand for 'print_exception(sys.exc_type, sys.exc_value, sys.exc_traceback, limit, file)'. |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 207 | (In fact, it uses sys.exc_info() to retrieve the same information |
| 208 | in a thread-safe way.)""" |
Raymond Hettinger | 10ff706 | 2002-06-02 03:04:52 +0000 | [diff] [blame] | 209 | if file is None: |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 210 | file = sys.stderr |
| 211 | try: |
| 212 | etype, value, tb = sys.exc_info() |
| 213 | print_exception(etype, value, tb, limit, file) |
| 214 | finally: |
| 215 | etype = value = tb = None |
Guido van Rossum | 526beed | 1994-07-01 15:36:46 +0000 | [diff] [blame] | 216 | |
Neil Schemenauer | f607fc5 | 2003-11-05 23:03:00 +0000 | [diff] [blame] | 217 | |
| 218 | def format_exc(limit=None): |
| 219 | """Like print_exc() but return a string.""" |
| 220 | try: |
| 221 | etype, value, tb = sys.exc_info() |
| 222 | return ''.join(format_exception(etype, value, tb, limit)) |
| 223 | finally: |
| 224 | etype = value = tb = None |
Tim Peters | 58eb11c | 2004-01-18 20:29:55 +0000 | [diff] [blame] | 225 | |
Neil Schemenauer | f607fc5 | 2003-11-05 23:03:00 +0000 | [diff] [blame] | 226 | |
Guido van Rossum | 194e20a | 1995-09-20 20:31:51 +0000 | [diff] [blame] | 227 | def print_last(limit=None, file=None): |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 228 | """This is a shorthand for 'print_exception(sys.last_type, |
| 229 | sys.last_value, sys.last_traceback, limit, file)'.""" |
Raymond Hettinger | 10ff706 | 2002-06-02 03:04:52 +0000 | [diff] [blame] | 230 | if file is None: |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 231 | file = sys.stderr |
| 232 | print_exception(sys.last_type, sys.last_value, sys.last_traceback, |
| 233 | limit, file) |
Guido van Rossum | dcc057a | 1996-08-12 23:18:13 +0000 | [diff] [blame] | 234 | |
| 235 | |
| 236 | def print_stack(f=None, limit=None, file=None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 237 | """Print a stack trace from its invocation point. |
Tim Peters | a19a168 | 2001-03-29 04:36:09 +0000 | [diff] [blame] | 238 | |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 239 | The optional 'f' argument can be used to specify an alternate |
| 240 | stack frame at which to start. The optional 'limit' and 'file' |
| 241 | arguments have the same meaning as for print_exception(). |
| 242 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 243 | if f is None: |
| 244 | try: |
| 245 | raise ZeroDivisionError |
| 246 | except ZeroDivisionError: |
| 247 | f = sys.exc_info()[2].tb_frame.f_back |
| 248 | print_list(extract_stack(f, limit), file) |
Guido van Rossum | dcc057a | 1996-08-12 23:18:13 +0000 | [diff] [blame] | 249 | |
| 250 | def format_stack(f=None, limit=None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 251 | """Shorthand for 'format_list(extract_stack(f, limit))'.""" |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 252 | if f is None: |
| 253 | try: |
| 254 | raise ZeroDivisionError |
| 255 | except ZeroDivisionError: |
| 256 | f = sys.exc_info()[2].tb_frame.f_back |
| 257 | return format_list(extract_stack(f, limit)) |
Guido van Rossum | dcc057a | 1996-08-12 23:18:13 +0000 | [diff] [blame] | 258 | |
| 259 | def extract_stack(f=None, limit = None): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 260 | """Extract the raw traceback from the current stack frame. |
| 261 | |
| 262 | The return value has the same format as for extract_tb(). The |
| 263 | optional 'f' and 'limit' arguments have the same meaning as for |
| 264 | print_stack(). Each item in the list is a quadruple (filename, |
| 265 | line number, function name, text), and the entries are in order |
| 266 | from oldest to newest stack frame. |
| 267 | """ |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 268 | if f is None: |
| 269 | try: |
| 270 | raise ZeroDivisionError |
| 271 | except ZeroDivisionError: |
| 272 | f = sys.exc_info()[2].tb_frame.f_back |
| 273 | if limit is None: |
| 274 | if hasattr(sys, 'tracebacklimit'): |
| 275 | limit = sys.tracebacklimit |
| 276 | list = [] |
| 277 | n = 0 |
| 278 | while f is not None and (limit is None or n < limit): |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 279 | lineno = f.f_lineno |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 280 | co = f.f_code |
| 281 | filename = co.co_filename |
| 282 | name = co.co_name |
Hye-Shik Chang | 182ac85 | 2004-10-26 09:16:42 +0000 | [diff] [blame] | 283 | linecache.checkcache(filename) |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 284 | line = linecache.getline(filename, lineno) |
Eric S. Raymond | ec3bbde | 2001-02-09 09:39:08 +0000 | [diff] [blame] | 285 | if line: line = line.strip() |
Tim Peters | b90f89a | 2001-01-15 03:26:36 +0000 | [diff] [blame] | 286 | else: line = None |
| 287 | list.append((filename, lineno, name, line)) |
| 288 | f = f.f_back |
| 289 | n = n+1 |
| 290 | list.reverse() |
| 291 | return list |
Guido van Rossum | 4752966 | 1997-09-26 22:43:02 +0000 | [diff] [blame] | 292 | |
Guido van Rossum | 4752966 | 1997-09-26 22:43:02 +0000 | [diff] [blame] | 293 | def tb_lineno(tb): |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 294 | """Calculate correct line number of traceback given in tb. |
Guido van Rossum | e7b146f | 2000-02-04 15:28:42 +0000 | [diff] [blame] | 295 | |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 296 | Obsolete in 2.3. |
Jeremy Hylton | 69e9e8b | 2001-03-21 19:09:31 +0000 | [diff] [blame] | 297 | """ |
Michael W. Hudson | dd32a91 | 2002-08-15 14:59:02 +0000 | [diff] [blame] | 298 | return tb.tb_lineno |