Backport PR #13175: Expand and Fix PDB skip.

IPython/core/debugger.py

@@ -1,1085 +1,1098 b''
 # -*- coding: utf-8 -*-
 """
 Pdb debugger class.
 
 
 This is an extension to PDB which adds a number of new features.
 Note that there is also the `IPython.terminal.debugger` class which provides UI
 improvements.
 
 We also strongly recommend to use this via the `ipdb` package, which provides
 extra configuration options.
 
 Among other things, this subclass of PDB:
  - supports many IPython magics like pdef/psource
  - hide frames in tracebacks based on `__tracebackhide__`
  - allows to skip frames based on `__debuggerskip__`
 
 The skipping and hiding frames are configurable via the `skip_predicates`
 command.
 
 By default, frames from readonly files will be hidden, frames containing
 ``__tracebackhide__=True`` will be hidden.
 
 Frames containing ``__debuggerskip__`` will be stepped over, frames who's parent
 frames value of ``__debuggerskip__`` is ``True`` will be skipped.
 
-    >>> def helper_1():
+    >>> def helpers_helper():
+    ...     pass
+    ...
+    ... def helper_1():
     ...     print("don't step in me")
+    ...     helpers_helpers() # will be stepped over unless breakpoint set.
     ...
     ...
     ... def helper_2():
     ...     print("in me neither")
     ...
 
 One can define a decorator that wraps a function between the two helpers:
 
     >>> def pdb_skipped_decorator(function):
     ...
     ...
     ...     def wrapped_fn(*args, **kwargs):
     ...         __debuggerskip__ = True
     ...         helper_1()
     ...         __debuggerskip__ = False
     ...         result = function(*args, **kwargs)
     ...         __debuggerskip__ = True
     ...         helper_2()
+    ...         # setting __debuggerskip__ to False again is not necessary
     ...         return result
     ...
     ...     return wrapped_fn
 
 When decorating a function, ipdb will directly step into ``bar()`` by
 default:
 
     >>> @foo_decorator
     ... def bar(x, y):
     ...     return x * y
 
 
 You can toggle the behavior with
 
     ipdb> skip_predicates debuggerskip false
 
 or configure it in your ``.pdbrc``
 
 
 
 Licencse
 --------
 
 Modified from the standard pdb.Pdb class to avoid including readline, so that
 the command line completion of other programs which include this isn't
 damaged.
 
 In the future, this class will be expanded with improvements over the standard
 pdb.
 
 The original code in this file is mainly lifted out of cmd.py in Python 2.2,
 with minor changes. Licensing should therefore be under the standard Python
 terms.  For details on the PSF (Python Software Foundation) standard license,
 see:
 
 https://docs.python.org/2/license.html
 
 
 All the changes since then are under the same license as IPython.
 
 """
 
 #*****************************************************************************
 #
 #       This file is licensed under the PSF license.
 #
 #       Copyright (C) 2001 Python Software Foundation, www.python.org
 #       Copyright (C) 2005-2006 Fernando Perez. <[e-mail]>
 #
 #
 #*****************************************************************************
 
 import bdb
 import functools
 import inspect
 import linecache
 import sys
 import warnings
 import re
 import os
 
 from IPython import get_ipython
 from IPython.utils import PyColorize
 from IPython.utils import coloransi, py3compat
 from IPython.core.excolors import exception_colors
 from IPython.testing.skipdoctest import skip_doctest
 
 
 prompt = 'ipdb> '
 
 #We have to check this directly from sys.argv, config struct not yet available
 from pdb import Pdb as OldPdb
 
 # Allow the set_trace code to operate outside of an ipython instance, even if
 # it does so with some limitations.  The rest of this support is implemented in
 # the Tracer constructor.
 
 DEBUGGERSKIP = "__debuggerskip__"
 
 
 def make_arrow(pad):
     """generate the leading arrow in front of traceback or debugger"""
     if pad >= 2:
         return '-'*(pad-2) + '> '
     elif pad == 1:
         return '>'
     return ''
 
 
 def BdbQuit_excepthook(et, ev, tb, excepthook=None):
     """Exception hook which handles `BdbQuit` exceptions.
 
     All other exceptions are processed using the `excepthook`
     parameter.
     """
     warnings.warn("`BdbQuit_excepthook` is deprecated since version 5.1",
                   DeprecationWarning, stacklevel=2)
     if et==bdb.BdbQuit:
         print('Exiting Debugger.')
     elif excepthook is not None:
         excepthook(et, ev, tb)
     else:
         # Backwards compatibility. Raise deprecation warning?
         BdbQuit_excepthook.excepthook_ori(et,ev,tb)
 
 
 def BdbQuit_IPython_excepthook(self,et,ev,tb,tb_offset=None):
     warnings.warn(
         "`BdbQuit_IPython_excepthook` is deprecated since version 5.1",
         DeprecationWarning, stacklevel=2)
     print('Exiting Debugger.')
 
 
 class Tracer(object):
     """
     DEPRECATED
 
     Class for local debugging, similar to pdb.set_trace.
 
     Instances of this class, when called, behave like pdb.set_trace, but
     providing IPython's enhanced capabilities.
 
     This is implemented as a class which must be initialized in your own code
     and not as a standalone function because we need to detect at runtime
     whether IPython is already active or not.  That detection is done in the
     constructor, ensuring that this code plays nicely with a running IPython,
     while functioning acceptably (though with limitations) if outside of it.
     """
 
     @skip_doctest
     def __init__(self, colors=None):
         """
         DEPRECATED
 
         Create a local debugger instance.
 
         Parameters
         ----------
 
         colors : str, optional
             The name of the color scheme to use, it must be one of IPython's
             valid color schemes.  If not given, the function will default to
             the current IPython scheme when running inside IPython, and to
             'NoColor' otherwise.
 
         Examples
         --------
         ::
 
             from IPython.core.debugger import Tracer; debug_here = Tracer()
 
         Later in your code::
 
             debug_here()  # -> will open up the debugger at that point.
 
         Once the debugger activates, you can use all of its regular commands to
         step through code, set breakpoints, etc.  See the pdb documentation
         from the Python standard library for usage details.
         """
         warnings.warn("`Tracer` is deprecated since version 5.1, directly use "
                       "`IPython.core.debugger.Pdb.set_trace()`",
                       DeprecationWarning, stacklevel=2)
 
         ip = get_ipython()
         if ip is None:
             # Outside of ipython, we set our own exception hook manually
             sys.excepthook = functools.partial(BdbQuit_excepthook,
                                                excepthook=sys.excepthook)
             def_colors = 'NoColor'
         else:
             # In ipython, we use its custom exception handler mechanism
             def_colors = ip.colors
             ip.set_custom_exc((bdb.BdbQuit,), BdbQuit_IPython_excepthook)
 
         if colors is None:
             colors = def_colors
 
         # The stdlib debugger internally uses a modified repr from the `repr`
         # module, that limits the length of printed strings to a hardcoded
         # limit of 30 characters.  That much trimming is too aggressive, let's
         # at least raise that limit to 80 chars, which should be enough for
         # most interactive uses.
         try:
             from reprlib import aRepr
             aRepr.maxstring = 80
         except:
             # This is only a user-facing convenience, so any error we encounter
             # here can be warned about but can be otherwise ignored.  These
             # printouts will tell us about problems if this API changes
             import traceback
             traceback.print_exc()
 
         self.debugger = Pdb(colors)
 
     def __call__(self):
         """Starts an interactive debugger at the point where called.
 
         This is similar to the pdb.set_trace() function from the std lib, but
         using IPython's enhanced debugger."""
 
         self.debugger.set_trace(sys._getframe().f_back)
 
 
 RGX_EXTRA_INDENT = re.compile(r'(?<=\n)\s+')
 
 
 def strip_indentation(multiline_string):
     return RGX_EXTRA_INDENT.sub('', multiline_string)
 
 
 def decorate_fn_with_doc(new_fn, old_fn, additional_text=""):
     """Make new_fn have old_fn's doc string. This is particularly useful
     for the ``do_...`` commands that hook into the help system.
     Adapted from from a comp.lang.python posting
     by Duncan Booth."""
     def wrapper(*args, **kw):
         return new_fn(*args, **kw)
     if old_fn.__doc__:
         wrapper.__doc__ = strip_indentation(old_fn.__doc__) + additional_text
     return wrapper
 
 
 class Pdb(OldPdb):
     """Modified Pdb class, does not load readline.
 
     for a standalone version that uses prompt_toolkit, see
     `IPython.terminal.debugger.TerminalPdb` and
     `IPython.terminal.debugger.set_trace()`
 
 
     This debugger can hide and skip frames that are tagged according to some predicates.
     See the `skip_predicates` commands.
 
     """
 
     default_predicates = {
         "tbhide": True,
         "readonly": False,
         "ipython_internal": True,
         "debuggerskip": True,
     }
 
     def __init__(self, color_scheme=None, completekey=None,
                  stdin=None, stdout=None, context=5, **kwargs):
         """Create a new IPython debugger.
 
         Parameters
         ----------
         color_scheme : default None
             Deprecated, do not use.
         completekey : default None
             Passed to pdb.Pdb.
         stdin : default None
             Passed to pdb.Pdb.
         stdout : default None
             Passed to pdb.Pdb.
         context : int
             Number of lines of source code context to show when
             displaying stacktrace information.
         **kwargs
             Passed to pdb.Pdb.
 
         Notes
         -----
         The possibilities are python version dependent, see the python
         docs for more info.
         """
 
         # Parent constructor:
         try:
             self.context = int(context)
             if self.context <= 0:
                 raise ValueError("Context must be a positive integer")
         except (TypeError, ValueError):
                 raise ValueError("Context must be a positive integer")
 
         # `kwargs` ensures full compatibility with stdlib's `pdb.Pdb`.
         OldPdb.__init__(self, completekey, stdin, stdout, **kwargs)
 
         # IPython changes...
         self.shell = get_ipython()
 
         if self.shell is None:
             save_main = sys.modules['__main__']
             # No IPython instance running, we must create one
             from IPython.terminal.interactiveshell import \
                 TerminalInteractiveShell
             self.shell = TerminalInteractiveShell.instance()
             # needed by any code which calls __import__("__main__") after
             # the debugger was entered. See also #9941.
             sys.modules['__main__'] = save_main 
 
         if color_scheme is not None:
             warnings.warn(
                 "The `color_scheme` argument is deprecated since version 5.1",
                 DeprecationWarning, stacklevel=2)
         else:
             color_scheme = self.shell.colors
 
         self.aliases = {}
 
         # Create color table: we copy the default one from the traceback
         # module and add a few attributes needed for debugging
         self.color_scheme_table = exception_colors()
 
         # shorthands
         C = coloransi.TermColors
         cst = self.color_scheme_table
 
         cst['NoColor'].colors.prompt = C.NoColor
         cst['NoColor'].colors.breakpoint_enabled = C.NoColor
         cst['NoColor'].colors.breakpoint_disabled = C.NoColor
 
         cst['Linux'].colors.prompt = C.Green
         cst['Linux'].colors.breakpoint_enabled = C.LightRed
         cst['Linux'].colors.breakpoint_disabled = C.Red
 
         cst['LightBG'].colors.prompt = C.Blue
         cst['LightBG'].colors.breakpoint_enabled = C.LightRed
         cst['LightBG'].colors.breakpoint_disabled = C.Red
 
         cst['Neutral'].colors.prompt = C.Blue
         cst['Neutral'].colors.breakpoint_enabled = C.LightRed
         cst['Neutral'].colors.breakpoint_disabled = C.Red
 
 
         # Add a python parser so we can syntax highlight source while
         # debugging.
         self.parser = PyColorize.Parser(style=color_scheme)
         self.set_colors(color_scheme)
 
         # Set the prompt - the default prompt is '(Pdb)'
         self.prompt = prompt
         self.skip_hidden = True
         self.report_skipped = True
 
         # list of predicates we use to skip frames
         self._predicates = self.default_predicates
 
     #
     def set_colors(self, scheme):
         """Shorthand access to the color table scheme selector method."""
         self.color_scheme_table.set_active_scheme(scheme)
         self.parser.style = scheme
 
     def set_trace(self, frame=None):
         if frame is None:
             frame = sys._getframe().f_back
         self.initial_frame = frame
         return super().set_trace(frame)
 
     def _hidden_predicate(self, frame):
         """
         Given a frame return whether it it should be hidden or not by IPython.
         """
 
         if self._predicates["readonly"]:
             fname = frame.f_code.co_filename
             # we need to check for file existence and interactively define
             # function would otherwise appear as RO.
             if os.path.isfile(fname) and not os.access(fname, os.W_OK):
                 return True
 
         if self._predicates["tbhide"]:
             if frame in (self.curframe, getattr(self, "initial_frame", None)):
                 return False
             else:
                 return self._get_frame_locals(frame).get("__tracebackhide__", False)
 
         return False
 
     def hidden_frames(self, stack):
         """
         Given an index in the stack return wether it should be skipped.
 
         This is used in up/down and where to skip frames.
         """
         # The f_locals dictionary is updated from the actual frame
         # locals whenever the .f_locals accessor is called, so we
         # avoid calling it here to preserve self.curframe_locals.
         # Futhermore, there is no good reason to hide the current frame.
         ip_hide = [self._hidden_predicate(s[0]) for s in stack]
         ip_start = [i for i, s in enumerate(ip_hide) if s == "__ipython_bottom__"]
         if ip_start and self._predicates["ipython_internal"]:
             ip_hide = [h if i > ip_start[0] else True for (i, h) in enumerate(ip_hide)]
         return ip_hide
 
     def interaction(self, frame, traceback):
         try:
             OldPdb.interaction(self, frame, traceback)
         except KeyboardInterrupt:
             self.stdout.write("\n" + self.shell.get_exception_only())
 
     def new_do_frame(self, arg):
         OldPdb.do_frame(self, arg)
 
     def new_do_quit(self, arg):
 
         if hasattr(self, 'old_all_completions'):
             self.shell.Completer.all_completions=self.old_all_completions
 
         return OldPdb.do_quit(self, arg)
 
     do_q = do_quit = decorate_fn_with_doc(new_do_quit, OldPdb.do_quit)
 
     def new_do_restart(self, arg):
         """Restart command. In the context of ipython this is exactly the same
         thing as 'quit'."""
         self.msg("Restart doesn't make sense here. Using 'quit' instead.")
         return self.do_quit(arg)
 
     def print_stack_trace(self, context=None):
         Colors = self.color_scheme_table.active_colors
         ColorsNormal = Colors.Normal
         if context is None:
             context = self.context
         try:
             context=int(context)
             if context <= 0:
                 raise ValueError("Context must be a positive integer")
         except (TypeError, ValueError):
                 raise ValueError("Context must be a positive integer")
         try:
             skipped = 0
             for hidden, frame_lineno in zip(self.hidden_frames(self.stack), self.stack):
                 if hidden and self.skip_hidden:
                     skipped += 1
                     continue
                 if skipped:
                     print(
                         f"{Colors.excName}    [... skipping {skipped} hidden frame(s)]{ColorsNormal}\n"
                     )
                     skipped = 0
                 self.print_stack_entry(frame_lineno, context=context)
             if skipped:
                 print(
                     f"{Colors.excName}    [... skipping {skipped} hidden frame(s)]{ColorsNormal}\n"
                 )
         except KeyboardInterrupt:
             pass
 
     def print_stack_entry(self, frame_lineno, prompt_prefix='\n-> ',
                           context=None):
         if context is None:
             context = self.context
         try:
             context=int(context)
             if context <= 0:
                 raise ValueError("Context must be a positive integer")
         except (TypeError, ValueError):
                 raise ValueError("Context must be a positive integer")
         print(self.format_stack_entry(frame_lineno, '', context), file=self.stdout)
 
         # vds: >>
         frame, lineno = frame_lineno
         filename = frame.f_code.co_filename
         self.shell.hooks.synchronize_with_editor(filename, lineno, 0)
         # vds: <<
 
     def _get_frame_locals(self, frame):
         """ "
         Acessing f_local of current frame reset the namespace, so we want to avoid
         that or the following can happend
 
         ipdb> foo
         "old"
         ipdb> foo = "new"
         ipdb> foo
         "new"
         ipdb> where
         ipdb> foo
         "old"
 
         So if frame is self.current_frame we instead return self.curframe_locals
 
         """
         if frame is self.curframe:
             return self.curframe_locals
         else:
             return frame.f_locals
 
     def format_stack_entry(self, frame_lineno, lprefix=': ', context=None):
         if context is None:
             context = self.context
         try:
             context=int(context)
             if context <= 0:
                 print("Context must be a positive integer", file=self.stdout)
         except (TypeError, ValueError):
                 print("Context must be a positive integer", file=self.stdout)
         try:
             import reprlib  # Py 3
         except ImportError:
             import repr as reprlib  # Py 2
 
         ret = []
 
         Colors = self.color_scheme_table.active_colors
         ColorsNormal = Colors.Normal
         tpl_link = u'%s%%s%s' % (Colors.filenameEm, ColorsNormal)
         tpl_call = u'%s%%s%s%%s%s' % (Colors.vName, Colors.valEm, ColorsNormal)
         tpl_line = u'%%s%s%%s %s%%s' % (Colors.lineno, ColorsNormal)
         tpl_line_em = u'%%s%s%%s %s%%s%s' % (Colors.linenoEm, Colors.line,
                                             ColorsNormal)
 
         frame, lineno = frame_lineno
 
         return_value = ''
         loc_frame = self._get_frame_locals(frame)
         if "__return__" in loc_frame:
             rv = loc_frame["__return__"]
             # return_value += '->'
             return_value += reprlib.repr(rv) + "\n"
         ret.append(return_value)
 
         #s = filename + '(' + `lineno` + ')'
         filename = self.canonic(frame.f_code.co_filename)
         link = tpl_link % py3compat.cast_unicode(filename)
 
         if frame.f_code.co_name:
             func = frame.f_code.co_name
         else:
             func = "<lambda>"
 
         call = ""
         if func != "?":
             if "__args__" in loc_frame:
                 args = reprlib.repr(loc_frame["__args__"])
             else:
                 args = '()'
             call = tpl_call % (func, args)
 
         # The level info should be generated in the same format pdb uses, to
         # avoid breaking the pdbtrack functionality of python-mode in *emacs.
         if frame is self.curframe:
             ret.append('> ')
         else:
             ret.append('  ')
         ret.append(u'%s(%s)%s\n' % (link,lineno,call))
 
         start = lineno - 1 - context//2
         lines = linecache.getlines(filename)
         start = min(start, len(lines) - context)
         start = max(start, 0)
         lines = lines[start : start + context]
 
         for i,line in enumerate(lines):
             show_arrow = (start + 1 + i == lineno)
             linetpl = (frame is self.curframe or show_arrow) \
                       and tpl_line_em \
                       or tpl_line
             ret.append(self.__format_line(linetpl, filename,
                                           start + 1 + i, line,
                                           arrow = show_arrow) )
         return ''.join(ret)
 
     def __format_line(self, tpl_line, filename, lineno, line, arrow = False):
         bp_mark = ""
         bp_mark_color = ""
 
         new_line, err = self.parser.format2(line, 'str')
         if not err:
             line = new_line
 
         bp = None
         if lineno in self.get_file_breaks(filename):
             bps = self.get_breaks(filename, lineno)
             bp = bps[-1]
 
         if bp:
             Colors = self.color_scheme_table.active_colors
             bp_mark = str(bp.number)
             bp_mark_color = Colors.breakpoint_enabled
             if not bp.enabled:
                 bp_mark_color = Colors.breakpoint_disabled
 
         numbers_width = 7
         if arrow:
             # This is the line with the error
             pad = numbers_width - len(str(lineno)) - len(bp_mark)
             num = '%s%s' % (make_arrow(pad), str(lineno))
         else:
             num = '%*s' % (numbers_width - len(bp_mark), str(lineno))
 
         return tpl_line % (bp_mark_color + bp_mark, num, line)
 
 
     def print_list_lines(self, filename, first, last):
         """The printing (as opposed to the parsing part of a 'list'
         command."""
         try:
             Colors = self.color_scheme_table.active_colors
             ColorsNormal = Colors.Normal
             tpl_line = '%%s%s%%s %s%%s' % (Colors.lineno, ColorsNormal)
             tpl_line_em = '%%s%s%%s %s%%s%s' % (Colors.linenoEm, Colors.line, ColorsNormal)
             src = []
             if filename == "<string>" and hasattr(self, "_exec_filename"):
                 filename = self._exec_filename
 
             for lineno in range(first, last+1):
                 line = linecache.getline(filename, lineno)
                 if not line:
                     break
 
                 if lineno == self.curframe.f_lineno:
                     line = self.__format_line(tpl_line_em, filename, lineno, line, arrow = True)
                 else:
                     line = self.__format_line(tpl_line, filename, lineno, line, arrow = False)
 
                 src.append(line)
                 self.lineno = lineno
 
             print(''.join(src), file=self.stdout)
 
         except KeyboardInterrupt:
             pass
 
     def do_skip_predicates(self, args):
         """
         Turn on/off individual predicates as to whether a frame should be hidden/skip.
 
         The global option to skip (or not) hidden frames is set with skip_hidden
 
         To change the value of a predicate
 
             skip_predicates key [true|false]
 
         Call without arguments to see the current values.
 
         To permanently change the value of an option add the corresponding
         command to your ``~/.pdbrc`` file. If you are programmatically using the
         Pdb instance you can also change the ``default_predicates`` class
         attribute.
         """
         if not args.strip():
             print("current predicates:")
             for (p, v) in self._predicates.items():
                 print("   ", p, ":", v)
             return
         type_value = args.strip().split(" ")
         if len(type_value) != 2:
             print(
                 f"Usage: skip_predicates <type> <value>, with <type> one of {set(self._predicates.keys())}"
             )
             return
 
         type_, value = type_value
         if type_ not in self._predicates:
             print(f"{type_!r} not in {set(self._predicates.keys())}")
             return
         if value.lower() not in ("true", "yes", "1", "no", "false", "0"):
             print(
                 f"{value!r} is invalid - use one of ('true', 'yes', '1', 'no', 'false', '0')"
             )
             return
 
         self._predicates[type_] = value.lower() in ("true", "yes", "1")
         if not any(self._predicates.values()):
             print(
                 "Warning, all predicates set to False, skip_hidden may not have any effects."
             )
 
     def do_skip_hidden(self, arg):
         """
         Change whether or not we should skip frames with the
         __tracebackhide__ attribute.
         """
         if not arg.strip():
             print(
                 f"skip_hidden = {self.skip_hidden}, use 'yes','no', 'true', or 'false' to change."
             )
         elif arg.strip().lower() in ("true", "yes"):
             self.skip_hidden = True
         elif arg.strip().lower() in ("false", "no"):
             self.skip_hidden = False
         if not any(self._predicates.values()):
             print(
                 "Warning, all predicates set to False, skip_hidden may not have any effects."
             )
 
     def do_list(self, arg):
         """Print lines of code from the current stack frame
         """
         self.lastcmd = 'list'
         last = None
         if arg:
             try:
                 x = eval(arg, {}, {})
                 if type(x) == type(()):
                     first, last = x
                     first = int(first)
                     last = int(last)
                     if last < first:
                         # Assume it's a count
                         last = first + last
                 else:
                     first = max(1, int(x) - 5)
             except:
                 print('*** Error in argument:', repr(arg), file=self.stdout)
                 return
         elif self.lineno is None:
             first = max(1, self.curframe.f_lineno - 5)
         else:
             first = self.lineno + 1
         if last is None:
             last = first + 10
         self.print_list_lines(self.curframe.f_code.co_filename, first, last)
 
         # vds: >>
         lineno = first
         filename = self.curframe.f_code.co_filename
         self.shell.hooks.synchronize_with_editor(filename, lineno, 0)
         # vds: <<
 
     do_l = do_list
 
     def getsourcelines(self, obj):
         lines, lineno = inspect.findsource(obj)
         if inspect.isframe(obj) and obj.f_globals is self._get_frame_locals(obj):
             # must be a module frame: do not try to cut a block out of it
             return lines, 1
         elif inspect.ismodule(obj):
             return lines, 1
         return inspect.getblock(lines[lineno:]), lineno+1
 
     def do_longlist(self, arg):
         """Print lines of code from the current stack frame.
 
         Shows more lines than 'list' does.
         """
         self.lastcmd = 'longlist'
         try:
             lines, lineno = self.getsourcelines(self.curframe)
         except OSError as err:
             self.error(err)
             return
         last = lineno + len(lines)
         self.print_list_lines(self.curframe.f_code.co_filename, lineno, last)
     do_ll = do_longlist
 
     def do_debug(self, arg):
         """debug code
         Enter a recursive debugger that steps through the code
         argument (which is an arbitrary expression or statement to be
         executed in the current environment).
         """
         trace_function = sys.gettrace()
         sys.settrace(None)
         globals = self.curframe.f_globals
         locals = self.curframe_locals
         p = self.__class__(completekey=self.completekey,
                            stdin=self.stdin, stdout=self.stdout)
         p.use_rawinput = self.use_rawinput
         p.prompt = "(%s) " % self.prompt.strip()
         self.message("ENTERING RECURSIVE DEBUGGER")
         sys.call_tracing(p.run, (arg, globals, locals))
         self.message("LEAVING RECURSIVE DEBUGGER")
         sys.settrace(trace_function)
         self.lastcmd = p.lastcmd
 
     def do_pdef(self, arg):
         """Print the call signature for any callable object.
 
         The debugger interface to %pdef"""
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("pdef")(arg, namespaces=namespaces)
 
     def do_pdoc(self, arg):
         """Print the docstring for an object.
 
         The debugger interface to %pdoc."""
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("pdoc")(arg, namespaces=namespaces)
 
     def do_pfile(self, arg):
         """Print (or run through pager) the file where an object is defined.
 
         The debugger interface to %pfile.
         """
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("pfile")(arg, namespaces=namespaces)
 
     def do_pinfo(self, arg):
         """Provide detailed information about an object.
 
         The debugger interface to %pinfo, i.e., obj?."""
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("pinfo")(arg, namespaces=namespaces)
 
     def do_pinfo2(self, arg):
         """Provide extra detailed information about an object.
 
         The debugger interface to %pinfo2, i.e., obj??."""
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("pinfo2")(arg, namespaces=namespaces)
 
     def do_psource(self, arg):
         """Print (or run through pager) the source code for an object."""
         namespaces = [
             ("Locals", self.curframe_locals),
             ("Globals", self.curframe.f_globals),
         ]
         self.shell.find_line_magic("psource")(arg, namespaces=namespaces)
 
     def do_where(self, arg):
         """w(here)
         Print a stack trace, with the most recent frame at the bottom.
         An arrow indicates the "current frame", which determines the
         context of most commands. 'bt' is an alias for this command.
 
         Take a number as argument as an (optional) number of context line to
         print"""
         if arg:
             try:
                 context = int(arg)
             except ValueError as err:
                 self.error(err)
                 return
             self.print_stack_trace(context)
         else:
             self.print_stack_trace()
 
     do_w = do_where
 
     def break_anywhere(self, frame):
         """
 
         _stop_in_decorator_internals is overly restrictive, as we may still want
         to trace function calls, so we need to also update break_anywhere so
         that is we don't `stop_here`, because of debugger skip, we may still
         stop at any point inside the function
 
         """
+
+        sup = super().break_anywhere(frame)
+        if sup:
+            return sup
         if self._predicates["debuggerskip"]:
             if DEBUGGERSKIP in frame.f_code.co_varnames:
                 return True
             if frame.f_back and self._get_frame_locals(frame.f_back).get(DEBUGGERSKIP):
                 return True
-        return super().break_anywhere(frame)
+        return False
 
     @skip_doctest
     def _is_in_decorator_internal_and_should_skip(self, frame):
         """
         Utility to tell us whether we are in a decorator internal and should stop.
 
 
 
         """
 
         # if we are disabled don't skip
         if not self._predicates["debuggerskip"]:
             return False
 
         # if frame is tagged, skip by default.
         if DEBUGGERSKIP in frame.f_code.co_varnames:
             return True
 
-        # if parent frame value set to True skip as well.
-        if frame.f_back and self._get_frame_locals(frame.f_back).get(DEBUGGERSKIP):
+        # if one of the parent frame value set to True skip as well.
+
+        cframe = frame
+        while getattr(cframe, "f_back", None):
+            cframe = cframe.f_back
+            if self._get_frame_locals(cframe).get(DEBUGGERSKIP):
             return True
 
         return False
 
     def stop_here(self, frame):
         """Check if pdb should stop here"""
         if not super().stop_here(frame):
             return False
 
         if self._is_in_decorator_internal_and_should_skip(frame) is True:
             return False
 
         hidden = False
         if self.skip_hidden:
             hidden = self._hidden_predicate(frame)
         if hidden:
             if self.report_skipped:
                 Colors = self.color_scheme_table.active_colors
                 ColorsNormal = Colors.Normal
                 print(f"{Colors.excName}    [... skipped 1 hidden frame]{ColorsNormal}\n")
             return False
         return True
 
     def do_up(self, arg):
         """u(p) [count]
         Move the current frame count (default one) levels up in the
         stack trace (to an older frame).
 
         Will skip hidden frames.
         """
         # modified version of upstream that skips
         # frames with __tracebackhide__
         if self.curindex == 0:
             self.error("Oldest frame")
             return
         try:
             count = int(arg or 1)
         except ValueError:
             self.error("Invalid frame count (%s)" % arg)
             return
         skipped = 0
         if count < 0:
             _newframe = 0
         else:
             _newindex = self.curindex
             counter = 0
             hidden_frames = self.hidden_frames(self.stack)
             for i in range(self.curindex - 1, -1, -1):
                 frame = self.stack[i][0]
                 if hidden_frames[i] and self.skip_hidden:
                     skipped += 1
                     continue
                 counter += 1
                 if counter >= count:
                     break
             else:
                 # if no break occured.
                 self.error("all frames above hidden")
                 return
 
             Colors = self.color_scheme_table.active_colors
             ColorsNormal = Colors.Normal
             _newframe = i
         self._select_frame(_newframe)
         if skipped:
             print(
                 f"{Colors.excName}    [... skipped {skipped} hidden frame(s)]{ColorsNormal}\n"
             )
 
     def do_down(self, arg):
         """d(own) [count]
         Move the current frame count (default one) levels down in the
         stack trace (to a newer frame).
 
         Will skip hidden frames.
         """
         if self.curindex + 1 == len(self.stack):
             self.error("Newest frame")
             return
         try:
             count = int(arg or 1)
         except ValueError:
             self.error("Invalid frame count (%s)" % arg)
             return
         if count < 0:
             _newframe = len(self.stack) - 1
         else:
             _newindex = self.curindex
             counter = 0
             skipped = 0
             hidden_frames = self.hidden_frames(self.stack)
             for i in range(self.curindex + 1, len(self.stack)):
                 frame = self.stack[i][0]
                 if hidden_frames[i] and self.skip_hidden:
                     skipped += 1
                     continue
                 counter += 1
                 if counter >= count:
                     break
             else:
                 self.error("all frames bellow hidden")
                 return
 
             Colors = self.color_scheme_table.active_colors
             ColorsNormal = Colors.Normal
             if skipped:
                 print(
                     f"{Colors.excName}    [... skipped {skipped} hidden frame(s)]{ColorsNormal}\n"
                 )
             _newframe = i
 
         self._select_frame(_newframe)
 
     do_d = do_down
     do_u = do_up
 
     def do_context(self, context):
         """context number_of_lines
         Set the number of lines of source code to show when displaying
         stacktrace information.
         """
         try:
             new_context = int(context)
             if new_context <= 0:
                 raise ValueError()
             self.context = new_context
         except ValueError:
             self.error("The 'context' command requires a positive integer argument.")
 
 
 class InterruptiblePdb(Pdb):
     """Version of debugger where KeyboardInterrupt exits the debugger altogether."""
 
     def cmdloop(self, intro=None):
         """Wrap cmdloop() such that KeyboardInterrupt stops the debugger."""
         try:
             return OldPdb.cmdloop(self, intro=intro)
         except KeyboardInterrupt:
             self.stop_here = lambda frame: False
             self.do_quit("")
             sys.settrace(None)
             self.quitting = False
             raise
 
     def _cmdloop(self):
         while True:
             try:
                 # keyboard interrupts allow for an easy way to cancel
                 # the current command, so allow them during interactive input
                 self.allow_kbdint = True
                 self.cmdloop()
                 self.allow_kbdint = False
                 break
             except KeyboardInterrupt:
                 self.message('--KeyboardInterrupt--')
                 raise
 
 
 def set_trace(frame=None):
     """
     Start debugging from `frame`.
 
     If frame is not specified, debugging starts from caller's frame.
     """
     Pdb().set_trace(frame or sys._getframe().f_back)

IPython/core/tests/test_debugger.py

@@ -1,505 +1,579 b''
 """Tests for debugging machinery.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import bdb
 import builtins
 import os
 import signal
 import subprocess
 import sys
 import time
 import warnings
+
 from subprocess import PIPE, CalledProcessError, check_output
 from tempfile import NamedTemporaryFile
 from textwrap import dedent
 from unittest.mock import patch
 
 import nose.tools as nt
 
 from IPython.core import debugger
 from IPython.testing import IPYTHON_TESTING_TIMEOUT_SCALE
 from IPython.testing.decorators import skip_win32
 
 #-----------------------------------------------------------------------------
 # Helper classes, from CPython's Pdb test suite
 #-----------------------------------------------------------------------------
 
 class _FakeInput(object):
     """
     A fake input stream for pdb's interactive debugger.  Whenever a
     line is read, print it (to simulate the user typing it), and then
     return it.  The set of lines to return is specified in the
     constructor; they should not have trailing newlines.
     """
     def __init__(self, lines):
         self.lines = iter(lines)
 
     def readline(self):
         line = next(self.lines)
         print(line)
         return line+'\n'
 
 class PdbTestInput(object):
     """Context manager that makes testing Pdb in doctests easier."""
 
     def __init__(self, input):
         self.input = input
 
     def __enter__(self):
         self.real_stdin = sys.stdin
         sys.stdin = _FakeInput(self.input)
 
     def __exit__(self, *exc):
         sys.stdin = self.real_stdin
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
 def test_longer_repr():
     try:
         from reprlib import repr as trepr  # Py 3
     except ImportError:
         from repr import repr as trepr  # Py 2
     
     a = '1234567890'* 7
     ar = "'1234567890123456789012345678901234567890123456789012345678901234567890'"
     a_trunc = "'123456789012...8901234567890'"
     nt.assert_equal(trepr(a), a_trunc)
     # The creation of our tracer modifies the repr module's repr function
     # in-place, since that global is used directly by the stdlib's pdb module.
     with warnings.catch_warnings():
         warnings.simplefilter('ignore', DeprecationWarning)
         debugger.Tracer()
     nt.assert_equal(trepr(a), ar)
 
 def test_ipdb_magics():
     '''Test calling some IPython magics from ipdb.
 
     First, set up some test functions and classes which we can inspect.
 
     >>> class ExampleClass(object):
     ...    """Docstring for ExampleClass."""
     ...    def __init__(self):
     ...        """Docstring for ExampleClass.__init__"""
     ...        pass
     ...    def __str__(self):
     ...        return "ExampleClass()"
 
     >>> def example_function(x, y, z="hello"):
     ...     """Docstring for example_function."""
     ...     pass
 
     >>> old_trace = sys.gettrace()
 
     Create a function which triggers ipdb.
 
     >>> def trigger_ipdb():
     ...    a = ExampleClass()
     ...    debugger.Pdb().set_trace()
 
     >>> with PdbTestInput([
     ...    'pdef example_function',
     ...    'pdoc ExampleClass',
     ...    'up',
     ...    'down',
     ...    'list',
     ...    'pinfo a',
     ...    'll',
     ...    'continue',
     ... ]):
     ...     trigger_ipdb()
     --Return--
     None
     > <doctest ...>(3)trigger_ipdb()
           1 def trigger_ipdb():
           2    a = ExampleClass()
     ----> 3    debugger.Pdb().set_trace()
     <BLANKLINE>
     ipdb> pdef example_function
      example_function(x, y, z='hello')
      ipdb> pdoc ExampleClass
     Class docstring:
         Docstring for ExampleClass.
     Init docstring:
         Docstring for ExampleClass.__init__
     ipdb> up
     > <doctest ...>(11)<module>()
           7    'pinfo a',
           8    'll',
           9    'continue',
          10 ]):
     ---> 11     trigger_ipdb()
     <BLANKLINE>
     ipdb> down
     None
     > <doctest ...>(3)trigger_ipdb()
           1 def trigger_ipdb():
           2    a = ExampleClass()
     ----> 3    debugger.Pdb().set_trace()
     <BLANKLINE>
     ipdb> list
           1 def trigger_ipdb():
           2    a = ExampleClass()
     ----> 3    debugger.Pdb().set_trace()
     <BLANKLINE>
     ipdb> pinfo a
     Type:           ExampleClass
     String form:    ExampleClass()
     Namespace:      Local...
     Docstring:      Docstring for ExampleClass.
     Init docstring: Docstring for ExampleClass.__init__
     ipdb> ll
           1 def trigger_ipdb():
           2    a = ExampleClass()
     ----> 3    debugger.Pdb().set_trace()
     <BLANKLINE>
     ipdb> continue
     
     Restore previous trace function, e.g. for coverage.py    
     
     >>> sys.settrace(old_trace)
     '''
 
 def test_ipdb_magics2():
     '''Test ipdb with a very short function.
     
     >>> old_trace = sys.gettrace()
 
     >>> def bar():
     ...     pass
 
     Run ipdb.
 
     >>> with PdbTestInput([
     ...    'continue',
     ... ]):
     ...     debugger.Pdb().runcall(bar)
     > <doctest ...>(2)bar()
           1 def bar():
     ----> 2    pass
     <BLANKLINE>
     ipdb> continue
     
     Restore previous trace function, e.g. for coverage.py    
     
     >>> sys.settrace(old_trace)
     '''
 
 def can_quit():
     '''Test that quit work in ipydb
 
     >>> old_trace = sys.gettrace()
 
     >>> def bar():
     ...     pass
 
     >>> with PdbTestInput([
     ...    'quit',
     ... ]):
     ...     debugger.Pdb().runcall(bar)
     > <doctest ...>(2)bar()
             1 def bar():
     ----> 2    pass
     <BLANKLINE>
     ipdb> quit
 
     Restore previous trace function, e.g. for coverage.py
 
     >>> sys.settrace(old_trace)
     '''
 
 
 def can_exit():
     '''Test that quit work in ipydb
 
     >>> old_trace = sys.gettrace()
 
     >>> def bar():
     ...     pass
 
     >>> with PdbTestInput([
     ...    'exit',
     ... ]):
     ...     debugger.Pdb().runcall(bar)
     > <doctest ...>(2)bar()
             1 def bar():
     ----> 2    pass
     <BLANKLINE>
     ipdb> exit
 
     Restore previous trace function, e.g. for coverage.py
 
     >>> sys.settrace(old_trace)
     '''
 
 
 def test_interruptible_core_debugger():
     """The debugger can be interrupted.
 
     The presumption is there is some mechanism that causes a KeyboardInterrupt
     (this is implemented in ipykernel).  We want to ensure the
     KeyboardInterrupt cause debugging to cease.
     """
     def raising_input(msg="", called=[0]):
         called[0] += 1
         if called[0] == 1:
             raise KeyboardInterrupt()
         else:
             raise AssertionError("input() should only be called once!")
 
     with patch.object(builtins, "input", raising_input):
         debugger.InterruptiblePdb().set_trace()
         # The way this test will fail is by set_trace() never exiting,
         # resulting in a timeout by the test runner. The alternative
         # implementation would involve a subprocess, but that adds issues with
         # interrupting subprocesses that are rather complex, so it's simpler
         # just to do it this way.
 
 @skip_win32
 def test_xmode_skip():
     """that xmode skip frames
 
     Not as a doctest as pytest does not run doctests.
     """
     import pexpect
     env = os.environ.copy()
     env["IPY_TEST_SIMPLE_PROMPT"] = "1"
 
     child = pexpect.spawn(
         sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
     )
     child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
 
     child.expect("IPython")
     child.expect("\n")
     child.expect_exact("In [1]")
 
     block = dedent(
         """
     def f():
         __tracebackhide__ = True
         g()
 
     def g():
         raise ValueError
 
     f()
     """
     )
 
     for line in block.splitlines():
         child.sendline(line)
         child.expect_exact(line)
     child.expect_exact("skipping")
 
     block = dedent(
         """
     def f():
         __tracebackhide__ = True
         g()
 
     def g():
         from IPython.core.debugger import set_trace
         set_trace()
 
     f()
     """
     )
 
     for line in block.splitlines():
         child.sendline(line)
         child.expect_exact(line)
 
     child.expect("ipdb>")
     child.sendline("w")
     child.expect("hidden")
     child.expect("ipdb>")
     child.sendline("skip_hidden false")
     child.sendline("w")
     child.expect("__traceba")
     child.expect("ipdb>")
 
     child.close()
 
 
 skip_decorators_blocks = (
     """
+    def helpers_helper():
+        pass # should not stop here except breakpoint
+    """,
+    """
     def helper_1():
-        pass # should not stop here
+        helpers_helper() # should not stop here
     """,
     """
     def helper_2():
         pass # should not stop here
     """,
     """
+    def pdb_skipped_decorator2(function):
+        def wrapped_fn(*args, **kwargs):
+            __debuggerskip__ = True
+            helper_2()
+            __debuggerskip__ = False
+            result = function(*args, **kwargs)
+            __debuggerskip__ = True
+            helper_2()
+            return result
+        return wrapped_fn
+    """,
+    """
     def pdb_skipped_decorator(function):
         def wrapped_fn(*args, **kwargs):
             __debuggerskip__ = True
             helper_1()
             __debuggerskip__ = False
             result = function(*args, **kwargs)
             __debuggerskip__ = True
             helper_2()
             return result
         return wrapped_fn
     """,
     """
     @pdb_skipped_decorator
+    @pdb_skipped_decorator2
     def bar(x, y):
         return x * y
     """,
     """import IPython.terminal.debugger as ipdb""",
     """
     def f():
         ipdb.set_trace()
         bar(3, 4)
     """,
     """
     f()
     """,
 )
 
 
 def _decorator_skip_setup():
     import pexpect
 
     env = os.environ.copy()
     env["IPY_TEST_SIMPLE_PROMPT"] = "1"
 
     child = pexpect.spawn(
         sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
     )
     child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE
 
     child.expect("IPython")
     child.expect("\n")
 
     dedented_blocks = [dedent(b).strip() for b in skip_decorators_blocks]
     in_prompt_number = 1
     for cblock in dedented_blocks:
         child.expect_exact(f"In [{in_prompt_number}]:")
         in_prompt_number += 1
         for line in cblock.splitlines():
             child.sendline(line)
             child.expect_exact(line)
         child.sendline("")
     return child
 
 
 @skip_win32
 def test_decorator_skip():
     """test that decorator frames can be skipped."""
 
     child = _decorator_skip_setup()
 
     child.expect_exact("3     bar(3, 4)")
     child.expect("ipdb>")
 
     child.expect("ipdb>")
     child.sendline("step")
     child.expect_exact("step")
 
     child.expect_exact("1 @pdb_skipped_decorator")
 
     child.sendline("s")
     child.expect_exact("return x * y")
 
     child.close()
 
 
 @skip_win32
 def test_decorator_skip_disabled():
     """test that decorator frame skipping can be disabled"""
 
     child = _decorator_skip_setup()
 
     child.expect_exact("3     bar(3, 4)")
 
     for input_, expected in [
         ("skip_predicates debuggerskip False", ""),
         ("skip_predicates", "debuggerskip : False"),
         ("step", "---> 2     def wrapped_fn"),
         ("step", "----> 3         __debuggerskip__"),
         ("step", "----> 4         helper_1()"),
         ("step", "---> 1 def helper_1():"),
-        ("next", "----> 2     pass"),
+        ("next", "----> 2     helpers_helper()"),
         ("next", "--Return--"),
         ("next", "----> 5         __debuggerskip__ = False"),
     ]:
         child.expect("ipdb>")
         child.sendline(input_)
         child.expect_exact(input_)
         child.expect_exact(expected)
 
     child.close()
 
 
 @skip_win32
+def test_decorator_skip_with_breakpoint():
+    """test that decorator frame skipping can be disabled"""
+
+    import pexpect
+
+    env = os.environ.copy()
+    env["IPY_TEST_SIMPLE_PROMPT"] = "1"
+
+    child = pexpect.spawn(
+        sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
+    )
+    child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE
+
+    child.expect("IPython")
+    child.expect("\n")
+
+    ### we need a filename, so we need to exec the full block with a filename
+    with NamedTemporaryFile(suffix=".py", dir=".", delete=True) as tf:
+
+        name = tf.name[:-3].split("/")[-1]
+        tf.write("\n".join([dedent(x) for x in skip_decorators_blocks[:-1]]).encode())
+        tf.flush()
+        codeblock = f"from {name} import f"
+
+        dedented_blocks = [
+            codeblock,
+            "f()",
+        ]
+
+        in_prompt_number = 1
+        for cblock in dedented_blocks:
+            child.expect_exact(f"In [{in_prompt_number}]:")
+            in_prompt_number += 1
+            for line in cblock.splitlines():
+                child.sendline(line)
+                child.expect_exact(line)
+            child.sendline("")
+
+        # as the filename does not exists, we'll rely on the filename prompt
+        child.expect_exact("47     bar(3, 4)")
+
+        for input_, expected in [
+            (f"b {name}.py:3", ""),
+            ("step", "1---> 3     pass # should not stop here except"),
+            ("step", "---> 38 @pdb_skipped_decorator"),
+            ("continue", ""),
+        ]:
+            child.expect("ipdb>")
+            child.sendline(input_)
+            child.expect_exact(input_)
+            child.expect_exact(expected)
+
+    child.close()
+
+
+@skip_win32
 def test_where_erase_value():
     """Test that `where` does not access f_locals and erase values."""
     import pexpect
 
     env = os.environ.copy()
     env["IPY_TEST_SIMPLE_PROMPT"] = "1"
 
     child = pexpect.spawn(
         sys.executable, ["-m", "IPython", "--colors=nocolor"], env=env
     )
     child.timeout = 15 * IPYTHON_TESTING_TIMEOUT_SCALE
 
     child.expect("IPython")
     child.expect("\n")
     child.expect_exact("In [1]")
 
     block = dedent(
         """
     def simple_f():
          myvar = 1
          print(myvar)
          1/0
          print(myvar)
     simple_f()    """
     )
 
     for line in block.splitlines():
         child.sendline(line)
         child.expect_exact(line)
     child.expect_exact("ZeroDivisionError")
     child.expect_exact("In [2]:")
 
     child.sendline("%debug")
 
     ##
     child.expect("ipdb>")
 
     child.sendline("myvar")
     child.expect("1")
 
     ##
     child.expect("ipdb>")
 
     child.sendline("myvar = 2")
 
     ##
     child.expect_exact("ipdb>")
 
     child.sendline("myvar")
 
     child.expect_exact("2")
 
     ##
     child.expect("ipdb>")
     child.sendline("where")
 
     ##
     child.expect("ipdb>")
     child.sendline("myvar")
 
     child.expect_exact("2")
     child.expect("ipdb>")
 
     child.close()