Uploaded Test files

venv/Lib/site-packages/IPython/core/debugger.py

@@ -0,0 +1,804 @@
+# -*- coding: utf-8 -*-
+"""
+Pdb debugger class.
+
+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 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
+"""
+
+#*****************************************************************************
+#
+#       This file is licensed under the PSF license.
+#
+#       Copyright (C) 2001 Python Software Foundation, www.python.org
+#       Copyright (C) 2005-2006 Fernando Perez. <fperez@colorado.edu>
+#
+#
+#*****************************************************************************
+
+import bdb
+import functools
+import inspect
+import linecache
+import sys
+import warnings
+import re
+
+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.
+
+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()`
+    """
+
+    def __init__(self, color_scheme=None, completekey=None,
+                 stdin=None, stdout=None, context=5, **kwargs):
+        """Create a new IPython debugger.
+        
+        :param color_scheme: Deprecated, do not use.
+        :param completekey: Passed to pdb.Pdb.
+        :param stdin: Passed to pdb.Pdb.
+        :param stdout: Passed to pdb.Pdb.
+        :param context: Number of lines of source code context to show when
+            displaying stacktrace information.
+        :param kwargs: Passed to pdb.Pdb.
+            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
+
+    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 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.
+        """
+        ip_hide = [s[0].f_locals.get("__tracebackhide__", False) for s in stack]
+        ip_start = [i for i, s in enumerate(ip_hide) if s == "__ipython_bottom__"]
+        if ip_start:
+            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 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 = ''
+        if '__return__' in frame.f_locals:
+            rv = frame.f_locals['__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 frame.f_locals:
+                args = reprlib.repr(frame.f_locals['__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_hidden(self, arg):
+        """
+        Change whether or not we should skip frames with the
+        __tracebackhide__ attribute.
+        """
+        if arg.strip().lower() in ("true", "yes"):
+            self.skip_hidden = True
+        elif arg.strip().lower() in ("false", "no"):
+            self.skip_hidden = False
+
+    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 obj.f_locals:
+            # 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).
+        """
+        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(self.trace_dispatch)
+        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.f_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.f_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.f_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.f_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.f_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.f_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 stop_here(self, frame):
+        hidden = False
+        if self.skip_hidden:
+            hidden = frame.f_locals.get("__tracebackhide__", False)
+        if hidden:
+            Colors = self.color_scheme_table.active_colors
+            ColorsNormal = Colors.Normal
+            print(f"{Colors.excName}    [... skipped 1 hidden frame]{ColorsNormal}\n")
+
+        return super().stop_here(frame)
+
+    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 __tracebackide__
+        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
+
+class InterruptiblePdb(Pdb):
+    """Version of debugger where KeyboardInterrupt exits the debugger altogether."""
+
+    def cmdloop(self):
+        """Wrap cmdloop() such that KeyboardInterrupt stops the debugger."""
+        try:
+            return OldPdb.cmdloop(self)
+        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)