def showtraceback(self):
"""Display the exception that just occurred.
We remove the first stack item because it is our own code.
The output is written by self.write(), below.
"""
try:
type, value, tb = sys.exc_info()
sys.last_type = type
sys.last_value = value
sys.last_traceback = tb
tblist = traceback.extract_tb(tb)
del tblist[:1]
list = traceback.format_list(tblist)
if list:
list.insert(0, "Traceback (most recent call last):\n")
list[len(list):] = traceback.format_exception_only(type, value)
finally:
tblist = tb = None
map(self.write, list)
python类last_traceback()的实例源码
def debugger(self,force=False):
"""Call the pdb debugger.
Keywords:
- force(False): by default, this routine checks the instance call_pdb
flag and does not actually invoke the debugger if the flag is false.
The 'force' option forces the debugger to activate even if the flag
is false.
"""
if not (force or self.call_pdb):
return
if not hasattr(sys,'last_traceback'):
error('No traceback has been produced, nothing to debug.')
return
self.InteractiveTB.debugger(force=True)
#-------------------------------------------------------------------------
# Things related to IPython's various namespaces
#-------------------------------------------------------------------------
def showsyntaxerror(self, filename=None):
"""Display the syntax error that just occurred.
This doesn't display a stack trace because there isn't one.
If a filename is given, it is stuffed in the exception instead
of what was there before (because Python's parser always uses
"<string>" when reading from a string).
"""
etype, value, last_traceback = self._get_exc_info()
if filename and issubclass(etype, SyntaxError):
try:
value.filename = filename
except:
# Not the format we expect; leave it alone
pass
stb = self.SyntaxTB.structured_traceback(etype, value, [])
self._showtraceback(etype, value, stb)
# This is overridden in TerminalInteractiveShell to show a message about
# the %paste magic.
def debugger(self,force=False):
"""Call the pdb debugger.
Keywords:
- force(False): by default, this routine checks the instance call_pdb
flag and does not actually invoke the debugger if the flag is false.
The 'force' option forces the debugger to activate even if the flag
is false.
"""
if not (force or self.call_pdb):
return
if not hasattr(sys,'last_traceback'):
error('No traceback has been produced, nothing to debug.')
return
self.InteractiveTB.debugger(force=True)
#-------------------------------------------------------------------------
# Things related to IPython's various namespaces
#-------------------------------------------------------------------------
def pm():
post_mortem(sys.last_traceback)
# Main program for testing
def print_last(limit=None, file=None):
"""This is a shorthand for 'print_exception(sys.last_type,
sys.last_value, sys.last_traceback, limit, file)'."""
if not hasattr(sys, "last_type"):
raise ValueError("no last exception")
if file is None:
file = sys.stderr
print_exception(sys.last_type, sys.last_value, sys.last_traceback,
limit, file)
def distb(tb=None):
"""Disassemble a traceback (default: last traceback)."""
if tb is None:
try:
tb = sys.last_traceback
except AttributeError:
raise RuntimeError, "no last traceback to disassemble"
while tb.tb_next: tb = tb.tb_next
disassemble(tb.tb_frame.f_code, tb.tb_lasti)
def showsyntaxerror(self, filename=None):
"""Display the syntax error that just occurred.
This doesn't display a stack trace because there isn't one.
If a filename is given, it is stuffed in the exception instead
of what was there before (because Python's parser always uses
"<string>" when reading from a string).
The output is written by self.write(), below.
"""
type, value, sys.last_traceback = sys.exc_info()
sys.last_type = type
sys.last_value = value
if filename and type is SyntaxError:
# Work hard to stuff the correct filename in the exception
try:
msg, (dummy_filename, lineno, offset, line) = value
except:
# Not the format we expect; leave it alone
pass
else:
# Stuff in the right filename
value = SyntaxError(msg, (filename, lineno, offset, line))
sys.last_value = value
list = traceback.format_exception_only(type, value)
map(self.write, list)
def showtraceback(self):
"""Display the exception that just occurred.
We remove the first stack item because it is our own code.
The output is written by self.write(), below.
"""
try:
type, value, tb = sys.exc_info()
sys.last_type = type
sys.last_value = value
sys.last_traceback = tb
tblist = traceback.extract_tb(tb)
del tblist[:1]
list = traceback.format_list(tblist)
if list:
list.insert(0, "Traceback (most recent call last):\n")
list[len(list):] = traceback.format_exception_only(type, value)
finally:
tblist = tb = None
map(self.write, list)
def __call__(self, *args):
## Start by extending recursion depth just a bit.
## If the error we are catching is due to recursion, we don't want to generate another one here.
recursionLimit = sys.getrecursionlimit()
try:
sys.setrecursionlimit(recursionLimit+100)
## call original exception handler first (prints exception)
global original_excepthook, callbacks, clear_tracebacks
try:
print("===== %s =====" % str(time.strftime("%Y.%m.%d %H:%m:%S", time.localtime(time.time()))))
except Exception:
sys.stderr.write("Warning: stdout is broken! Falling back to stderr.\n")
sys.stdout = sys.stderr
ret = original_excepthook(*args)
for cb in callbacks:
try:
cb(*args)
except Exception:
print(" --------------------------------------------------------------")
print(" Error occurred during exception callback %s" % str(cb))
print(" --------------------------------------------------------------")
traceback.print_exception(*sys.exc_info())
## Clear long-term storage of last traceback to prevent memory-hogging.
## (If an exception occurs while a lot of data is present on the stack,
## such as when loading large files, the data would ordinarily be kept
## until the next exception occurs. We would rather release this memory
## as soon as possible.)
if clear_tracebacks is True:
sys.last_traceback = None
finally:
sys.setrecursionlimit(recursionLimit)
def __call__(self, *args):
## Start by extending recursion depth just a bit.
## If the error we are catching is due to recursion, we don't want to generate another one here.
recursionLimit = sys.getrecursionlimit()
try:
sys.setrecursionlimit(recursionLimit+100)
## call original exception handler first (prints exception)
global original_excepthook, callbacks, clear_tracebacks
try:
print("===== %s =====" % str(time.strftime("%Y.%m.%d %H:%m:%S", time.localtime(time.time()))))
except Exception:
sys.stderr.write("Warning: stdout is broken! Falling back to stderr.\n")
sys.stdout = sys.stderr
ret = original_excepthook(*args)
for cb in callbacks:
try:
cb(*args)
except Exception:
print(" --------------------------------------------------------------")
print(" Error occurred during exception callback %s" % str(cb))
print(" --------------------------------------------------------------")
traceback.print_exception(*sys.exc_info())
## Clear long-term storage of last traceback to prevent memory-hogging.
## (If an exception occurs while a lot of data is present on the stack,
## such as when loading large files, the data would ordinarily be kept
## until the next exception occurs. We would rather release this memory
## as soon as possible.)
if clear_tracebacks is True:
sys.last_traceback = None
finally:
sys.setrecursionlimit(recursionLimit)
def pm():
post_mortem(sys.last_traceback)
# Main program for testing
def print_last(limit=None, file=None):
"""This is a shorthand for 'print_exception(sys.last_type,
sys.last_value, sys.last_traceback, limit, file)'."""
if not hasattr(sys, "last_type"):
raise ValueError("no last exception")
if file is None:
file = sys.stderr
print_exception(sys.last_type, sys.last_value, sys.last_traceback,
limit, file)
def pytest_runtest_call(item):
try:
item.runtest()
except Exception:
# Store trace info to allow postmortem debugging
type, value, tb = sys.exc_info()
tb = tb.tb_next # Skip *this* frame
sys.last_type = type
sys.last_value = value
sys.last_traceback = tb
del tb # Get rid of it in this namespace
raise
def distb(tb=None):
"""Disassemble a traceback (default: last traceback)."""
if tb is None:
try:
tb = sys.last_traceback
except AttributeError:
raise RuntimeError, "no last traceback to disassemble"
while tb.tb_next: tb = tb.tb_next
disassemble(tb.tb_frame.f_code, tb.tb_lasti)
def showsyntaxerror(self, filename=None):
"""Display the syntax error that just occurred.
This doesn't display a stack trace because there isn't one.
If a filename is given, it is stuffed in the exception instead
of what was there before (because Python's parser always uses
"<string>" when reading from a string).
The output is written by self.write(), below.
"""
type, value, sys.last_traceback = sys.exc_info()
sys.last_type = type
sys.last_value = value
if filename and type is SyntaxError:
# Work hard to stuff the correct filename in the exception
try:
msg, (dummy_filename, lineno, offset, line) = value
except:
# Not the format we expect; leave it alone
pass
else:
# Stuff in the right filename
value = SyntaxError(msg, (filename, lineno, offset, line))
sys.last_value = value
list = traceback.format_exception_only(type, value)
map(self.write, list)
def print_last(limit=None, file=None, chain=True):
"""This is a shorthand for 'print_exception(sys.last_type,
sys.last_value, sys.last_traceback, limit, file)'."""
if not hasattr(sys, "last_type"):
raise ValueError("no last exception")
print_exception(sys.last_type, sys.last_value, sys.last_traceback,
limit, file, chain)
#
# Printing and Extracting Stacks.
#
def print_last(limit=None, file=None, chain=True):
"""This is a shorthand for 'print_exception(sys.last_type,
sys.last_value, sys.last_traceback, limit, file)'."""
if not hasattr(sys, "last_type"):
raise ValueError("no last exception")
print_exception(sys.last_type, sys.last_value, sys.last_traceback,
limit, file, chain)
#
# Printing and Extracting Stacks.
#
def report_callback_exception(self, exc, val, tb):
"""Report callback exception on sys.stderr.
Applications may want to override this internal function, and
should when sys.stderr is None."""
import traceback
print("Exception in Tkinter callback", file=sys.stderr)
sys.last_type = exc
sys.last_value = val
sys.last_traceback = tb
traceback.print_exception(exc, val, tb)
def report_callback_exception(self, exc, val, tb):
"""Report callback exception on sys.stderr.
Applications may want to override this internal function, and
should when sys.stderr is None."""
import traceback
print("Exception in Tkinter callback", file=sys.stderr)
sys.last_type = exc
sys.last_value = val
sys.last_traceback = tb
traceback.print_exception(exc, val, tb)
