capture_output does not respect trailing semicolon (#13940)

This change tests whether the Python code inside the `%%capture` magic
ends with a `';'`. If it does, the code no longer creates the object
that is supposed to store the cell output. If such object already
exists, it is deleted.
Please review and suggest changes if you think they can improve the
solution. Thanks.

IPython/core/magics/execution.py

@@ -1,1512 +1,1516 b''
 # -*- coding: utf-8 -*-
 """Implementation of execution-related magic functions."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 
 import ast
 import bdb
 import builtins as builtin_mod
 import cProfile as profile
 import gc
 import itertools
 import math
 import os
 import pstats
 import re
 import shlex
 import sys
 import time
 import timeit
 from ast import Module
 from io import StringIO
 from logging import error
 from pathlib import Path
 from pdb import Restart
 from warnings import warn
 
 from IPython.core import magic_arguments, oinspect, page
 from IPython.core.error import UsageError
 from IPython.core.macro import Macro
 from IPython.core.magic import (
     Magics,
     cell_magic,
     line_cell_magic,
     line_magic,
     magics_class,
     needs_local_scope,
     no_var_expand,
     output_can_be_silenced,
     on_off,
 )
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils.capture import capture_output
 from IPython.utils.contexts import preserve_keys
 from IPython.utils.ipstruct import Struct
 from IPython.utils.module_paths import find_mod
 from IPython.utils.path import get_py_filename, shellglob
 from IPython.utils.timing import clock, clock2
+from IPython.core.displayhook import DisplayHook
 
 #-----------------------------------------------------------------------------
 # Magic implementation classes
 #-----------------------------------------------------------------------------
 
 
 class TimeitResult(object):
     """
     Object returned by the timeit magic with info about the run.
 
     Contains the following attributes :
 
     loops: (int) number of loops done per measurement
     repeat: (int) number of times the measurement has been repeated
     best: (float) best execution time / number
     all_runs: (list of float) execution time of each run (in s)
     compile_time: (float) time of statement compilation (s)
 
     """
     def __init__(self, loops, repeat, best, worst, all_runs, compile_time, precision):
         self.loops = loops
         self.repeat = repeat
         self.best = best
         self.worst = worst
         self.all_runs = all_runs
         self.compile_time = compile_time
         self._precision = precision
         self.timings = [ dt / self.loops for dt in all_runs]
 
     @property
     def average(self):
         return math.fsum(self.timings) / len(self.timings)
 
     @property
     def stdev(self):
         mean = self.average
         return (math.fsum([(x - mean) ** 2 for x in self.timings]) / len(self.timings)) ** 0.5
 
     def __str__(self):
         pm = '+-'
         if hasattr(sys.stdout, 'encoding') and sys.stdout.encoding:
             try:
                 u'\xb1'.encode(sys.stdout.encoding)
                 pm = u'\xb1'
             except:
                 pass
         return "{mean} {pm} {std} per loop (mean {pm} std. dev. of {runs} run{run_plural}, {loops:,} loop{loop_plural} each)".format(
             pm=pm,
             runs=self.repeat,
             loops=self.loops,
             loop_plural="" if self.loops == 1 else "s",
             run_plural="" if self.repeat == 1 else "s",
             mean=_format_time(self.average, self._precision),
             std=_format_time(self.stdev, self._precision),
         )
 
     def _repr_pretty_(self, p , cycle):
         unic = self.__str__()
         p.text(u'<TimeitResult : '+unic+u'>')
 
 
 class TimeitTemplateFiller(ast.NodeTransformer):
     """Fill in the AST template for timing execution.
 
     This is quite closely tied to the template definition, which is in
     :meth:`ExecutionMagics.timeit`.
     """
     def __init__(self, ast_setup, ast_stmt):
         self.ast_setup = ast_setup
         self.ast_stmt = ast_stmt
 
     def visit_FunctionDef(self, node):
         "Fill in the setup statement"
         self.generic_visit(node)
         if node.name == "inner":
             node.body[:1] = self.ast_setup.body
 
         return node
 
     def visit_For(self, node):
         "Fill in the statement to be timed"
         if getattr(getattr(node.body[0], 'value', None), 'id', None) == 'stmt':
             node.body = self.ast_stmt.body
         return node
 
 
 class Timer(timeit.Timer):
     """Timer class that explicitly uses self.inner
     
     which is an undocumented implementation detail of CPython,
     not shared by PyPy.
     """
     # Timer.timeit copied from CPython 3.4.2
     def timeit(self, number=timeit.default_number):
         """Time 'number' executions of the main statement.
 
         To be precise, this executes the setup statement once, and
         then returns the time it takes to execute the main statement
         a number of times, as a float measured in seconds.  The
         argument is the number of times through the loop, defaulting
         to one million.  The main statement, the setup statement and
         the timer function to be used are passed to the constructor.
         """
         it = itertools.repeat(None, number)
         gcold = gc.isenabled()
         gc.disable()
         try:
             timing = self.inner(it, self.timer)
         finally:
             if gcold:
                 gc.enable()
         return timing
 
 
 @magics_class
 class ExecutionMagics(Magics):
     """Magics related to code execution, debugging, profiling, etc.
 
     """
 
     def __init__(self, shell):
         super(ExecutionMagics, self).__init__(shell)
         # Default execution function used to actually run user code.
         self.default_runner = None
 
     @skip_doctest
     @no_var_expand
     @line_cell_magic
     def prun(self, parameter_s='', cell=None):
 
         """Run a statement through the python code profiler.
 
         Usage, in line mode:
           %prun [options] statement
 
         Usage, in cell mode:
           %%prun [options] [statement]
           code...
           code...
 
         In cell mode, the additional code lines are appended to the (possibly
         empty) statement in the first line.  Cell mode allows you to easily
         profile multiline blocks without having to put them in a separate
         function.
 
         The given statement (which doesn't require quote marks) is run via the
         python profiler in a manner similar to the profile.run() function.
         Namespaces are internally managed to work correctly; profile.run
         cannot be used in IPython because it makes certain assumptions about
         namespaces which do not hold under IPython.
 
         Options:
 
         -l <limit>
           you can place restrictions on what or how much of the
           profile gets printed. The limit value can be:
 
              * A string: only information for function names containing this string
                is printed.
 
              * An integer: only these many lines are printed.
 
              * A float (between 0 and 1): this fraction of the report is printed
                (for example, use a limit of 0.4 to see the topmost 40% only).
 
           You can combine several limits with repeated use of the option. For
           example, ``-l __init__ -l 5`` will print only the topmost 5 lines of
           information about class constructors.
 
         -r
           return the pstats.Stats object generated by the profiling. This
           object has all the information about the profile in it, and you can
           later use it for further analysis or in other functions.
 
         -s <key>
           sort profile by given key. You can provide more than one key
           by using the option several times: '-s key1 -s key2 -s key3...'. The
           default sorting key is 'time'.
 
           The following is copied verbatim from the profile documentation
           referenced below:
 
           When more than one key is provided, additional keys are used as
           secondary criteria when the there is equality in all keys selected
           before them.
 
           Abbreviations can be used for any key names, as long as the
           abbreviation is unambiguous.  The following are the keys currently
           defined:
 
           ============  =====================
           Valid Arg     Meaning
           ============  =====================
           "calls"       call count
           "cumulative"  cumulative time
           "file"        file name
           "module"      file name
           "pcalls"      primitive call count
           "line"        line number
           "name"        function name
           "nfl"         name/file/line
           "stdname"     standard name
           "time"        internal time
           ============  =====================
 
           Note that all sorts on statistics are in descending order (placing
           most time consuming items first), where as name, file, and line number
           searches are in ascending order (i.e., alphabetical). The subtle
           distinction between "nfl" and "stdname" is that the standard name is a
           sort of the name as printed, which means that the embedded line
           numbers get compared in an odd way.  For example, lines 3, 20, and 40
           would (if the file names were the same) appear in the string order
           "20" "3" and "40".  In contrast, "nfl" does a numeric compare of the
           line numbers.  In fact, sort_stats("nfl") is the same as
           sort_stats("name", "file", "line").
 
         -T <filename>
           save profile results as shown on screen to a text
           file. The profile is still shown on screen.
 
         -D <filename>
           save (via dump_stats) profile statistics to given
           filename. This data is in a format understood by the pstats module, and
           is generated by a call to the dump_stats() method of profile
           objects. The profile is still shown on screen.
 
         -q
           suppress output to the pager.  Best used with -T and/or -D above.
 
         If you want to run complete programs under the profiler's control, use
         ``%run -p [prof_opts] filename.py [args to program]`` where prof_opts
         contains profiler specific options as described here.
 
         You can read the complete documentation for the profile module with::
 
           In [1]: import profile; profile.help()
 
         .. versionchanged:: 7.3
             User variables are no longer expanded,
             the magic line is always left unmodified.
 
         """
         opts, arg_str = self.parse_options(parameter_s, 'D:l:rs:T:q',
                                            list_all=True, posix=False)
         if cell is not None:
             arg_str += '\n' + cell
         arg_str = self.shell.transform_cell(arg_str)
         return self._run_with_profiler(arg_str, opts, self.shell.user_ns)
 
     def _run_with_profiler(self, code, opts, namespace):
         """
         Run `code` with profiler.  Used by ``%prun`` and ``%run -p``.
 
         Parameters
         ----------
         code : str
             Code to be executed.
         opts : Struct
             Options parsed by `self.parse_options`.
         namespace : dict
             A dictionary for Python namespace (e.g., `self.shell.user_ns`).
 
         """
 
         # Fill default values for unspecified options:
         opts.merge(Struct(D=[''], l=[], s=['time'], T=['']))
 
         prof = profile.Profile()
         try:
             prof = prof.runctx(code, namespace, namespace)
             sys_exit = ''
         except SystemExit:
             sys_exit = """*** SystemExit exception caught in code being profiled."""
 
         stats = pstats.Stats(prof).strip_dirs().sort_stats(*opts.s)
 
         lims = opts.l
         if lims:
             lims = []  # rebuild lims with ints/floats/strings
             for lim in opts.l:
                 try:
                     lims.append(int(lim))
                 except ValueError:
                     try:
                         lims.append(float(lim))
                     except ValueError:
                         lims.append(lim)
 
         # Trap output.
         stdout_trap = StringIO()
         stats_stream = stats.stream
         try:
             stats.stream = stdout_trap
             stats.print_stats(*lims)
         finally:
             stats.stream = stats_stream
 
         output = stdout_trap.getvalue()
         output = output.rstrip()
 
         if 'q' not in opts:
             page.page(output)
         print(sys_exit, end=' ')
 
         dump_file = opts.D[0]
         text_file = opts.T[0]
         if dump_file:
             prof.dump_stats(dump_file)
             print(
                 f"\n*** Profile stats marshalled to file {repr(dump_file)}.{sys_exit}"
             )
         if text_file:
             pfile = Path(text_file)
             pfile.touch(exist_ok=True)
             pfile.write_text(output, encoding="utf-8")
 
             print(
                 f"\n*** Profile printout saved to text file {repr(text_file)}.{sys_exit}"
             )
 
         if 'r' in opts:
             return stats
 
         return None
 
     @line_magic
     def pdb(self, parameter_s=''):
         """Control the automatic calling of the pdb interactive debugger.
 
         Call as '%pdb on', '%pdb 1', '%pdb off' or '%pdb 0'. If called without
         argument it works as a toggle.
 
         When an exception is triggered, IPython can optionally call the
         interactive pdb debugger after the traceback printout. %pdb toggles
         this feature on and off.
 
         The initial state of this feature is set in your configuration
         file (the option is ``InteractiveShell.pdb``).
 
         If you want to just activate the debugger AFTER an exception has fired,
         without having to type '%pdb on' and rerunning your code, you can use
         the %debug magic."""
 
         par = parameter_s.strip().lower()
 
         if par:
             try:
                 new_pdb = {'off':0,'0':0,'on':1,'1':1}[par]
             except KeyError:
                 print ('Incorrect argument. Use on/1, off/0, '
                        'or nothing for a toggle.')
                 return
         else:
             # toggle
             new_pdb = not self.shell.call_pdb
 
         # set on the shell
         self.shell.call_pdb = new_pdb
         print('Automatic pdb calling has been turned',on_off(new_pdb))
 
     @magic_arguments.magic_arguments()
     @magic_arguments.argument('--breakpoint', '-b', metavar='FILE:LINE',
         help="""
         Set break point at LINE in FILE.
         """
     )
     @magic_arguments.argument('statement', nargs='*',
         help="""
         Code to run in debugger.
         You can omit this in cell magic mode.
         """
     )
     @no_var_expand
     @line_cell_magic
     def debug(self, line='', cell=None):
         """Activate the interactive debugger.
 
         This magic command support two ways of activating debugger.
         One is to activate debugger before executing code.  This way, you
         can set a break point, to step through the code from the point.
         You can use this mode by giving statements to execute and optionally
         a breakpoint.
 
         The other one is to activate debugger in post-mortem mode.  You can
         activate this mode simply running %debug without any argument.
         If an exception has just occurred, this lets you inspect its stack
         frames interactively.  Note that this will always work only on the last
         traceback that occurred, so you must call this quickly after an
         exception that you wish to inspect has fired, because if another one
         occurs, it clobbers the previous one.
 
         If you want IPython to automatically do this on every exception, see
         the %pdb magic for more details.
 
         .. versionchanged:: 7.3
             When running code, user variables are no longer expanded,
             the magic line is always left unmodified.
 
         """
         args = magic_arguments.parse_argstring(self.debug, line)
 
         if not (args.breakpoint or args.statement or cell):
             self._debug_post_mortem()
         elif not (args.breakpoint or cell):
             # If there is no breakpoints, the line is just code to execute
             self._debug_exec(line, None)
         else:
             # Here we try to reconstruct the code from the output of
             # parse_argstring. This might not work if the code has spaces
             # For example this fails for `print("a b")`
             code = "\n".join(args.statement)
             if cell:
                 code += "\n" + cell
             self._debug_exec(code, args.breakpoint)
 
     def _debug_post_mortem(self):
         self.shell.debugger(force=True)
 
     def _debug_exec(self, code, breakpoint):
         if breakpoint:
             (filename, bp_line) = breakpoint.rsplit(':', 1)
             bp_line = int(bp_line)
         else:
             (filename, bp_line) = (None, None)
         self._run_with_debugger(code, self.shell.user_ns, filename, bp_line)
 
     @line_magic
     def tb(self, s):
         """Print the last traceback.
 
         Optionally, specify an exception reporting mode, tuning the
         verbosity of the traceback. By default the currently-active exception
         mode is used. See %xmode for changing exception reporting modes.
 
         Valid modes: Plain, Context, Verbose, and Minimal.
         """
         interactive_tb = self.shell.InteractiveTB
         if s:
             # Switch exception reporting mode for this one call.
             # Ensure it is switched back.
             def xmode_switch_err(name):
                 warn('Error changing %s exception modes.\n%s' %
                     (name,sys.exc_info()[1]))
 
             new_mode = s.strip().capitalize()
             original_mode = interactive_tb.mode
             try:
                 try:
                     interactive_tb.set_mode(mode=new_mode)
                 except Exception:
                     xmode_switch_err('user')
                 else:
                     self.shell.showtraceback()
             finally:
                 interactive_tb.set_mode(mode=original_mode)
         else:
             self.shell.showtraceback()
 
     @skip_doctest
     @line_magic
     def run(self, parameter_s='', runner=None,
                   file_finder=get_py_filename):
         """Run the named file inside IPython as a program.
 
         Usage::
 
           %run [-n -i -e -G]
                [( -t [-N<N>] | -d [-b<N>] | -p [profile options] )]
                ( -m mod | filename ) [args]
 
         The filename argument should be either a pure Python script (with
         extension ``.py``), or a file with custom IPython syntax (such as
         magics). If the latter, the file can be either a script with ``.ipy``
         extension, or a Jupyter notebook with ``.ipynb`` extension. When running
         a Jupyter notebook, the output from print statements and other
         displayed objects will appear in the terminal (even matplotlib figures
         will open, if a terminal-compliant backend is being used). Note that,
         at the system command line, the ``jupyter run`` command offers similar
         functionality for executing notebooks (albeit currently with some
         differences in supported options).
 
         Parameters after the filename are passed as command-line arguments to
         the program (put in sys.argv). Then, control returns to IPython's
         prompt.
 
         This is similar to running at a system prompt ``python file args``,
         but with the advantage of giving you IPython's tracebacks, and of
         loading all variables into your interactive namespace for further use
         (unless -p is used, see below).
 
         The file is executed in a namespace initially consisting only of
         ``__name__=='__main__'`` and sys.argv constructed as indicated. It thus
         sees its environment as if it were being run as a stand-alone program
         (except for sharing global objects such as previously imported
         modules). But after execution, the IPython interactive namespace gets
         updated with all variables defined in the program (except for __name__
         and sys.argv). This allows for very convenient loading of code for
         interactive work, while giving each program a 'clean sheet' to run in.
 
         Arguments are expanded using shell-like glob match.  Patterns
         '*', '?', '[seq]' and '[!seq]' can be used.  Additionally,
         tilde '~' will be expanded into user's home directory.  Unlike
         real shells, quotation does not suppress expansions.  Use
         *two* back slashes (e.g. ``\\\\*``) to suppress expansions.
         To completely disable these expansions, you can use -G flag.
 
         On Windows systems, the use of single quotes `'` when specifying
         a file is not supported. Use double quotes `"`.
 
         Options:
 
         -n
           __name__ is NOT set to '__main__', but to the running file's name
           without extension (as python does under import).  This allows running
           scripts and reloading the definitions in them without calling code
           protected by an ``if __name__ == "__main__"`` clause.
 
         -i
           run the file in IPython's namespace instead of an empty one. This
           is useful if you are experimenting with code written in a text editor
           which depends on variables defined interactively.
 
         -e
           ignore sys.exit() calls or SystemExit exceptions in the script
           being run.  This is particularly useful if IPython is being used to
           run unittests, which always exit with a sys.exit() call.  In such
           cases you are interested in the output of the test results, not in
           seeing a traceback of the unittest module.
 
         -t
           print timing information at the end of the run.  IPython will give
           you an estimated CPU time consumption for your script, which under
           Unix uses the resource module to avoid the wraparound problems of
           time.clock().  Under Unix, an estimate of time spent on system tasks
           is also given (for Windows platforms this is reported as 0.0).
 
         If -t is given, an additional ``-N<N>`` option can be given, where <N>
         must be an integer indicating how many times you want the script to
         run.  The final timing report will include total and per run results.
 
         For example (testing the script uniq_stable.py)::
 
             In [1]: run -t uniq_stable
 
             IPython CPU timings (estimated):
               User  :    0.19597 s.
               System:        0.0 s.
 
             In [2]: run -t -N5 uniq_stable
 
             IPython CPU timings (estimated):
             Total runs performed: 5
               Times :      Total       Per run
               User  :   0.910862 s,  0.1821724 s.
               System:        0.0 s,        0.0 s.
 
         -d
           run your program under the control of pdb, the Python debugger.
           This allows you to execute your program step by step, watch variables,
           etc.  Internally, what IPython does is similar to calling::
 
               pdb.run('execfile("YOURFILENAME")')
 
           with a breakpoint set on line 1 of your file.  You can change the line
           number for this automatic breakpoint to be <N> by using the -bN option
           (where N must be an integer). For example::
 
               %run -d -b40 myscript
 
           will set the first breakpoint at line 40 in myscript.py.  Note that
           the first breakpoint must be set on a line which actually does
           something (not a comment or docstring) for it to stop execution.
 
           Or you can specify a breakpoint in a different file::
 
               %run -d -b myotherfile.py:20 myscript
 
           When the pdb debugger starts, you will see a (Pdb) prompt.  You must
           first enter 'c' (without quotes) to start execution up to the first
           breakpoint.
 
           Entering 'help' gives information about the use of the debugger.  You
           can easily see pdb's full documentation with "import pdb;pdb.help()"
           at a prompt.
 
         -p
           run program under the control of the Python profiler module (which
           prints a detailed report of execution times, function calls, etc).
 
           You can pass other options after -p which affect the behavior of the
           profiler itself. See the docs for %prun for details.
 
           In this mode, the program's variables do NOT propagate back to the
           IPython interactive namespace (because they remain in the namespace
           where the profiler executes them).
 
           Internally this triggers a call to %prun, see its documentation for
           details on the options available specifically for profiling.
 
         There is one special usage for which the text above doesn't apply:
         if the filename ends with .ipy[nb], the file is run as ipython script,
         just as if the commands were written on IPython prompt.
 
         -m
           specify module name to load instead of script path. Similar to
           the -m option for the python interpreter. Use this option last if you
           want to combine with other %run options. Unlike the python interpreter
           only source modules are allowed no .pyc or .pyo files.
           For example::
 
               %run -m example
 
           will run the example module.
 
         -G
           disable shell-like glob expansion of arguments.
 
         """
 
         # Logic to handle issue #3664
         # Add '--' after '-m <module_name>' to ignore additional args passed to a module.
         if '-m' in parameter_s and '--' not in parameter_s:
             argv = shlex.split(parameter_s, posix=(os.name == 'posix'))
             for idx, arg in enumerate(argv):
                 if arg and arg.startswith('-') and arg != '-':
                     if arg == '-m':
                         argv.insert(idx + 2, '--')
                         break
                 else:
                     # Positional arg, break
                     break
             parameter_s = ' '.join(shlex.quote(arg) for arg in argv)
 
         # get arguments and set sys.argv for program to be run.
         opts, arg_lst = self.parse_options(parameter_s,
                                            'nidtN:b:pD:l:rs:T:em:G',
                                            mode='list', list_all=1)
         if "m" in opts:
             modulename = opts["m"][0]
             modpath = find_mod(modulename)
             if modpath is None:
                 msg = '%r is not a valid modulename on sys.path'%modulename
                 raise Exception(msg)
             arg_lst = [modpath] + arg_lst
         try:
             fpath = None # initialize to make sure fpath is in scope later
             fpath = arg_lst[0]
             filename = file_finder(fpath)
         except IndexError as e:
             msg = 'you must provide at least a filename.'
             raise Exception(msg) from e
         except IOError as e:
             try:
                 msg = str(e)
             except UnicodeError:
                 msg = e.message
             if os.name == 'nt' and re.match(r"^'.*'$",fpath):
                 warn('For Windows, use double quotes to wrap a filename: %run "mypath\\myfile.py"')
             raise Exception(msg) from e
         except TypeError:
             if fpath in sys.meta_path:
                 filename = ""
             else:
                 raise
 
         if filename.lower().endswith(('.ipy', '.ipynb')):
             with preserve_keys(self.shell.user_ns, '__file__'):
                 self.shell.user_ns['__file__'] = filename
                 self.shell.safe_execfile_ipy(filename, raise_exceptions=True)
             return
 
         # Control the response to exit() calls made by the script being run
         exit_ignore = 'e' in opts
 
         # Make sure that the running script gets a proper sys.argv as if it
         # were run from a system shell.
         save_argv = sys.argv # save it for later restoring
 
         if 'G' in opts:
             args = arg_lst[1:]
         else:
             # tilde and glob expansion
             args = shellglob(map(os.path.expanduser,  arg_lst[1:]))
 
         sys.argv = [filename] + args  # put in the proper filename
 
         if 'n' in opts:
             name = Path(filename).stem
         else:
             name = '__main__'
 
         if 'i' in opts:
             # Run in user's interactive namespace
             prog_ns = self.shell.user_ns
             __name__save = self.shell.user_ns['__name__']
             prog_ns['__name__'] = name
             main_mod = self.shell.user_module
 
             # Since '%run foo' emulates 'python foo.py' at the cmd line, we must
             # set the __file__ global in the script's namespace
             # TK: Is this necessary in interactive mode?
             prog_ns['__file__'] = filename
         else:
             # Run in a fresh, empty namespace
 
             # The shell MUST hold a reference to prog_ns so after %run
             # exits, the python deletion mechanism doesn't zero it out
             # (leaving dangling references). See interactiveshell for details
             main_mod = self.shell.new_main_mod(filename, name)
             prog_ns = main_mod.__dict__
 
         # pickle fix.  See interactiveshell for an explanation.  But we need to
         # make sure that, if we overwrite __main__, we replace it at the end
         main_mod_name = prog_ns['__name__']
 
         if main_mod_name == '__main__':
             restore_main = sys.modules['__main__']
         else:
             restore_main = False
 
         # This needs to be undone at the end to prevent holding references to
         # every single object ever created.
         sys.modules[main_mod_name] = main_mod
 
         if 'p' in opts or 'd' in opts:
             if 'm' in opts:
                 code = 'run_module(modulename, prog_ns)'
                 code_ns = {
                     'run_module': self.shell.safe_run_module,
                     'prog_ns': prog_ns,
                     'modulename': modulename,
                 }
             else:
                 if 'd' in opts:
                     # allow exceptions to raise in debug mode
                     code = 'execfile(filename, prog_ns, raise_exceptions=True)'
                 else:
                     code = 'execfile(filename, prog_ns)'
                 code_ns = {
                     'execfile': self.shell.safe_execfile,
                     'prog_ns': prog_ns,
                     'filename': get_py_filename(filename),
                 }
 
         try:
             stats = None
             if 'p' in opts:
                 stats = self._run_with_profiler(code, opts, code_ns)
             else:
                 if 'd' in opts:
                     bp_file, bp_line = parse_breakpoint(
                         opts.get('b', ['1'])[0], filename)
                     self._run_with_debugger(
                         code, code_ns, filename, bp_line, bp_file)
                 else:
                     if 'm' in opts:
                         def run():
                             self.shell.safe_run_module(modulename, prog_ns)
                     else:
                         if runner is None:
                             runner = self.default_runner
                         if runner is None:
                             runner = self.shell.safe_execfile
 
                         def run():
                             runner(filename, prog_ns, prog_ns,
                                     exit_ignore=exit_ignore)
 
                     if 't' in opts:
                         # timed execution
                         try:
                             nruns = int(opts['N'][0])
                             if nruns < 1:
                                 error('Number of runs must be >=1')
                                 return
                         except (KeyError):
                             nruns = 1
                         self._run_with_timing(run, nruns)
                     else:
                         # regular execution
                         run()
 
             if 'i' in opts:
                 self.shell.user_ns['__name__'] = __name__save
             else:
                 # update IPython interactive namespace
 
                 # Some forms of read errors on the file may mean the
                 # __name__ key was never set; using pop we don't have to
                 # worry about a possible KeyError.
                 prog_ns.pop('__name__', None)
 
                 with preserve_keys(self.shell.user_ns, '__file__'):
                     self.shell.user_ns.update(prog_ns)
         finally:
             # It's a bit of a mystery why, but __builtins__ can change from
             # being a module to becoming a dict missing some key data after
             # %run.  As best I can see, this is NOT something IPython is doing
             # at all, and similar problems have been reported before:
             # http://coding.derkeiler.com/Archive/Python/comp.lang.python/2004-10/0188.html
             # Since this seems to be done by the interpreter itself, the best
             # we can do is to at least restore __builtins__ for the user on
             # exit.
             self.shell.user_ns['__builtins__'] = builtin_mod
 
             # Ensure key global structures are restored
             sys.argv = save_argv
             if restore_main:
                 sys.modules['__main__'] = restore_main
                 if '__mp_main__' in sys.modules:
                     sys.modules['__mp_main__'] = restore_main
             else:
                 # Remove from sys.modules the reference to main_mod we'd
                 # added.  Otherwise it will trap references to objects
                 # contained therein.
                 del sys.modules[main_mod_name]
 
         return stats
 
     def _run_with_debugger(self, code, code_ns, filename=None,
                            bp_line=None, bp_file=None):
         """
         Run `code` in debugger with a break point.
 
         Parameters
         ----------
         code : str
             Code to execute.
         code_ns : dict
             A namespace in which `code` is executed.
         filename : str
             `code` is ran as if it is in `filename`.
         bp_line : int, optional
             Line number of the break point.
         bp_file : str, optional
             Path to the file in which break point is specified.
             `filename` is used if not given.
 
         Raises
         ------
         UsageError
             If the break point given by `bp_line` is not valid.
 
         """
         deb = self.shell.InteractiveTB.pdb
         if not deb:
             self.shell.InteractiveTB.pdb = self.shell.InteractiveTB.debugger_cls()
             deb = self.shell.InteractiveTB.pdb
 
         # deb.checkline() fails if deb.curframe exists but is None; it can
         # handle it not existing. https://github.com/ipython/ipython/issues/10028
         if hasattr(deb, 'curframe'):
             del deb.curframe
 
         # reset Breakpoint state, which is moronically kept
         # in a class
         bdb.Breakpoint.next = 1
         bdb.Breakpoint.bplist = {}
         bdb.Breakpoint.bpbynumber = [None]
         deb.clear_all_breaks()
         if bp_line is not None:
             # Set an initial breakpoint to stop execution
             maxtries = 10
             bp_file = bp_file or filename
             checkline = deb.checkline(bp_file, bp_line)
             if not checkline:
                 for bp in range(bp_line + 1, bp_line + maxtries + 1):
                     if deb.checkline(bp_file, bp):
                         break
                 else:
                     msg = ("\nI failed to find a valid line to set "
                            "a breakpoint\n"
                            "after trying up to line: %s.\n"
                            "Please set a valid breakpoint manually "
                            "with the -b option." % bp)
                     raise UsageError(msg)
             # if we find a good linenumber, set the breakpoint
             deb.do_break('%s:%s' % (bp_file, bp_line))
 
         if filename:
             # Mimic Pdb._runscript(...)
             deb._wait_for_mainpyfile = True
             deb.mainpyfile = deb.canonic(filename)
 
         # Start file run
         print("NOTE: Enter 'c' at the %s prompt to continue execution." % deb.prompt)
         try:
             if filename:
                 # save filename so it can be used by methods on the deb object
                 deb._exec_filename = filename
             while True:
                 try:
                     trace = sys.gettrace()
                     deb.run(code, code_ns)
                 except Restart:
                     print("Restarting")
                     if filename:
                         deb._wait_for_mainpyfile = True
                         deb.mainpyfile = deb.canonic(filename)
                     continue
                 else:
                     break
                 finally:
                     sys.settrace(trace)
             
 
         except:
             etype, value, tb = sys.exc_info()
             # Skip three frames in the traceback: the %run one,
             # one inside bdb.py, and the command-line typed by the
             # user (run by exec in pdb itself).
             self.shell.InteractiveTB(etype, value, tb, tb_offset=3)
 
     @staticmethod
     def _run_with_timing(run, nruns):
         """
         Run function `run` and print timing information.
 
         Parameters
         ----------
         run : callable
             Any callable object which takes no argument.
         nruns : int
             Number of times to execute `run`.
 
         """
         twall0 = time.perf_counter()
         if nruns == 1:
             t0 = clock2()
             run()
             t1 = clock2()
             t_usr = t1[0] - t0[0]
             t_sys = t1[1] - t0[1]
             print("\nIPython CPU timings (estimated):")
             print("  User   : %10.2f s." % t_usr)
             print("  System : %10.2f s." % t_sys)
         else:
             runs = range(nruns)
             t0 = clock2()
             for nr in runs:
                 run()
             t1 = clock2()
             t_usr = t1[0] - t0[0]
             t_sys = t1[1] - t0[1]
             print("\nIPython CPU timings (estimated):")
             print("Total runs performed:", nruns)
             print("  Times  : %10s   %10s" % ('Total', 'Per run'))
             print("  User   : %10.2f s, %10.2f s." % (t_usr, t_usr / nruns))
             print("  System : %10.2f s, %10.2f s." % (t_sys, t_sys / nruns))
         twall1 = time.perf_counter()
         print("Wall time: %10.2f s." % (twall1 - twall0))
 
     @skip_doctest
     @no_var_expand
     @line_cell_magic
     @needs_local_scope
     def timeit(self, line='', cell=None, local_ns=None):
         """Time execution of a Python statement or expression
 
         Usage, in line mode:
           %timeit [-n<N> -r<R> [-t|-c] -q -p<P> -o] statement
         or in cell mode:
           %%timeit [-n<N> -r<R> [-t|-c] -q -p<P> -o] setup_code
           code
           code...
 
         Time execution of a Python statement or expression using the timeit
         module.  This function can be used both as a line and cell magic:
 
         - In line mode you can time a single-line statement (though multiple
           ones can be chained with using semicolons).
 
         - In cell mode, the statement in the first line is used as setup code
           (executed but not timed) and the body of the cell is timed.  The cell
           body has access to any variables created in the setup code.
 
         Options:
         -n<N>: execute the given statement <N> times in a loop. If <N> is not
         provided, <N> is determined so as to get sufficient accuracy.
 
         -r<R>: number of repeats <R>, each consisting of <N> loops, and take the
         best result.
         Default: 7
 
         -t: use time.time to measure the time, which is the default on Unix.
         This function measures wall time.
 
         -c: use time.clock to measure the time, which is the default on
         Windows and measures wall time. On Unix, resource.getrusage is used
         instead and returns the CPU user time.
 
         -p<P>: use a precision of <P> digits to display the timing result.
         Default: 3
 
         -q: Quiet, do not print result.
 
         -o: return a TimeitResult that can be stored in a variable to inspect
             the result in more details.
 
         .. versionchanged:: 7.3
             User variables are no longer expanded,
             the magic line is always left unmodified.
 
         Examples
         --------
         ::
 
           In [1]: %timeit pass
           8.26 ns ± 0.12 ns per loop (mean ± std. dev. of 7 runs, 100000000 loops each)
 
           In [2]: u = None
 
           In [3]: %timeit u is None
           29.9 ns ± 0.643 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
 
           In [4]: %timeit -r 4 u == None
 
           In [5]: import time
 
           In [6]: %timeit -n1 time.sleep(2)
 
         The times reported by %timeit will be slightly higher than those
         reported by the timeit.py script when variables are accessed. This is
         due to the fact that %timeit executes the statement in the namespace
         of the shell, compared with timeit.py, which uses a single setup
         statement to import function or create variables. Generally, the bias
         does not matter as long as results from timeit.py are not mixed with
         those from %timeit."""
 
         opts, stmt = self.parse_options(
             line, "n:r:tcp:qo", posix=False, strict=False, preserve_non_opts=True
         )
         if stmt == "" and cell is None:
             return
         
         timefunc = timeit.default_timer
         number = int(getattr(opts, "n", 0))
         default_repeat = 7 if timeit.default_repeat < 7 else timeit.default_repeat
         repeat = int(getattr(opts, "r", default_repeat))
         precision = int(getattr(opts, "p", 3))
         quiet = 'q' in opts
         return_result = 'o' in opts
         if hasattr(opts, "t"):
             timefunc = time.time
         if hasattr(opts, "c"):
             timefunc = clock
 
         timer = Timer(timer=timefunc)
         # this code has tight coupling to the inner workings of timeit.Timer,
         # but is there a better way to achieve that the code stmt has access
         # to the shell namespace?
         transform  = self.shell.transform_cell
 
         if cell is None:
             # called as line magic
             ast_setup = self.shell.compile.ast_parse("pass")
             ast_stmt = self.shell.compile.ast_parse(transform(stmt))
         else:
             ast_setup = self.shell.compile.ast_parse(transform(stmt))
             ast_stmt = self.shell.compile.ast_parse(transform(cell))
 
         ast_setup = self.shell.transform_ast(ast_setup)
         ast_stmt = self.shell.transform_ast(ast_stmt)
 
         # Check that these compile to valid Python code *outside* the timer func
         # Invalid code may become valid when put inside the function & loop,
         # which messes up error messages.
         # https://github.com/ipython/ipython/issues/10636
         self.shell.compile(ast_setup, "<magic-timeit-setup>", "exec")
         self.shell.compile(ast_stmt, "<magic-timeit-stmt>", "exec")
 
         # This codestring is taken from timeit.template - we fill it in as an
         # AST, so that we can apply our AST transformations to the user code
         # without affecting the timing code.
         timeit_ast_template = ast.parse('def inner(_it, _timer):\n'
                                         '    setup\n'
                                         '    _t0 = _timer()\n'
                                         '    for _i in _it:\n'
                                         '        stmt\n'
                                         '    _t1 = _timer()\n'
                                         '    return _t1 - _t0\n')
 
         timeit_ast = TimeitTemplateFiller(ast_setup, ast_stmt).visit(timeit_ast_template)
         timeit_ast = ast.fix_missing_locations(timeit_ast)
 
         # Track compilation time so it can be reported if too long
         # Minimum time above which compilation time will be reported
         tc_min = 0.1
 
         t0 = clock()
         code = self.shell.compile(timeit_ast, "<magic-timeit>", "exec")
         tc = clock()-t0
 
         ns = {}
         glob = self.shell.user_ns
         # handles global vars with same name as local vars. We store them in conflict_globs.
         conflict_globs = {}
         if local_ns and cell is None:
             for var_name, var_val in glob.items():
                 if var_name in local_ns:
                     conflict_globs[var_name] = var_val
             glob.update(local_ns)
             
         exec(code, glob, ns)
         timer.inner = ns["inner"]
 
         # This is used to check if there is a huge difference between the
         # best and worst timings.
         # Issue: https://github.com/ipython/ipython/issues/6471
         if number == 0:
             # determine number so that 0.2 <= total time < 2.0
             for index in range(0, 10):
                 number = 10 ** index
                 time_number = timer.timeit(number)
                 if time_number >= 0.2:
                     break
 
         all_runs = timer.repeat(repeat, number)
         best = min(all_runs) / number
         worst = max(all_runs) / number
         timeit_result = TimeitResult(number, repeat, best, worst, all_runs, tc, precision)
 
         # Restore global vars from conflict_globs
         if conflict_globs:
            glob.update(conflict_globs)
                 
         if not quiet :
             # Check best timing is greater than zero to avoid a
             # ZeroDivisionError.
             # In cases where the slowest timing is lesser than a microsecond
             # we assume that it does not really matter if the fastest
             # timing is 4 times faster than the slowest timing or not.
             if worst > 4 * best and best > 0 and worst > 1e-6:
                 print("The slowest run took %0.2f times longer than the "
                       "fastest. This could mean that an intermediate result "
                       "is being cached." % (worst / best))
            
             print( timeit_result )
 
             if tc > tc_min:
                 print("Compiler time: %.2f s" % tc)
         if return_result:
             return timeit_result
 
     @skip_doctest
     @no_var_expand
     @needs_local_scope
     @line_cell_magic
     @output_can_be_silenced
     def time(self,line='', cell=None, local_ns=None):
         """Time execution of a Python statement or expression.
 
         The CPU and wall clock times are printed, and the value of the
         expression (if any) is returned.  Note that under Win32, system time
         is always reported as 0, since it can not be measured.
 
         This function can be used both as a line and cell magic:
 
         - In line mode you can time a single-line statement (though multiple
           ones can be chained with using semicolons).
 
         - In cell mode, you can time the cell body (a directly
           following statement raises an error).
 
         This function provides very basic timing functionality.  Use the timeit
         magic for more control over the measurement.
 
         .. versionchanged:: 7.3
             User variables are no longer expanded,
             the magic line is always left unmodified.
 
         Examples
         --------
         ::
 
           In [1]: %time 2**128
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00
           Out[1]: 340282366920938463463374607431768211456L
 
           In [2]: n = 1000000
 
           In [3]: %time sum(range(n))
           CPU times: user 1.20 s, sys: 0.05 s, total: 1.25 s
           Wall time: 1.37
           Out[3]: 499999500000L
 
           In [4]: %time print 'hello world'
           hello world
           CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
           Wall time: 0.00
 
         .. note::
             The time needed by Python to compile the given expression will be
             reported if it is more than 0.1s.
 
             In the example below, the actual exponentiation is done by Python
             at compilation time, so while the expression can take a noticeable
             amount of time to compute, that time is purely due to the
             compilation::
 
                 In [5]: %time 3**9999;
                 CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
                 Wall time: 0.00 s
 
                 In [6]: %time 3**999999;
                 CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
                 Wall time: 0.00 s
                 Compiler : 0.78 s
         """
         # fail immediately if the given expression can't be compiled
         
         if line and cell:
             raise UsageError("Can't use statement directly after '%%time'!")
         
         if cell:
             expr = self.shell.transform_cell(cell)
         else:
             expr = self.shell.transform_cell(line)
 
         # Minimum time above which parse time will be reported
         tp_min = 0.1
 
         t0 = clock()
         expr_ast = self.shell.compile.ast_parse(expr)
         tp = clock()-t0
 
         # Apply AST transformations
         expr_ast = self.shell.transform_ast(expr_ast)
 
         # Minimum time above which compilation time will be reported
         tc_min = 0.1
 
         expr_val=None
         if len(expr_ast.body)==1 and isinstance(expr_ast.body[0], ast.Expr):
             mode = 'eval'
             source = '<timed eval>'
             expr_ast = ast.Expression(expr_ast.body[0].value)
         else:
             mode = 'exec'
             source = '<timed exec>'
             # multi-line %%time case
             if len(expr_ast.body) > 1 and isinstance(expr_ast.body[-1], ast.Expr):
                 expr_val= expr_ast.body[-1]
                 expr_ast = expr_ast.body[:-1]
                 expr_ast = Module(expr_ast, [])
                 expr_val = ast.Expression(expr_val.value)
 
         t0 = clock()
         code = self.shell.compile(expr_ast, source, mode)
         tc = clock()-t0
 
         # skew measurement as little as possible
         glob = self.shell.user_ns
         wtime = time.time
         # time execution
         wall_st = wtime()
         if mode=='eval':
             st = clock2()
             try:
                 out = eval(code, glob, local_ns)
             except:
                 self.shell.showtraceback()
                 return
             end = clock2()
         else:
             st = clock2()
             try:
                 exec(code, glob, local_ns)
                 out=None
                 # multi-line %%time case
                 if expr_val is not None:
                     code_2 = self.shell.compile(expr_val, source, 'eval')
                     out = eval(code_2, glob, local_ns)
             except:
                 self.shell.showtraceback()
                 return
             end = clock2()
 
         wall_end = wtime()
         # Compute actual times and report
         wall_time = wall_end - wall_st
         cpu_user = end[0] - st[0]
         cpu_sys = end[1] - st[1]
         cpu_tot = cpu_user + cpu_sys
         # On windows cpu_sys is always zero, so only total is displayed
         if sys.platform != "win32":
             print(
                 f"CPU times: user {_format_time(cpu_user)}, sys: {_format_time(cpu_sys)}, total: {_format_time(cpu_tot)}"
             )
         else:
             print(f"CPU times: total: {_format_time(cpu_tot)}")
         print(f"Wall time: {_format_time(wall_time)}")
         if tc > tc_min:
             print(f"Compiler : {_format_time(tc)}")
         if tp > tp_min:
             print(f"Parser   : {_format_time(tp)}")
         return out
 
     @skip_doctest
     @line_magic
     def macro(self, parameter_s=''):
         """Define a macro for future re-execution. It accepts ranges of history,
         filenames or string objects.
 
         Usage:\\
           %macro [options] name n1-n2 n3-n4 ... n5 .. n6 ...
 
         Options:
 
           -r: use 'raw' input.  By default, the 'processed' history is used,
           so that magics are loaded in their transformed version to valid
           Python.  If this option is given, the raw input as typed at the
           command line is used instead.
           
           -q: quiet macro definition.  By default, a tag line is printed 
           to indicate the macro has been created, and then the contents of 
           the macro are printed.  If this option is given, then no printout
           is produced once the macro is created.
 
         This will define a global variable called `name` which is a string
         made of joining the slices and lines you specify (n1,n2,... numbers
         above) from your input history into a single string. This variable
         acts like an automatic function which re-executes those lines as if
         you had typed them. You just type 'name' at the prompt and the code
         executes.
 
         The syntax for indicating input ranges is described in %history.
 
         Note: as a 'hidden' feature, you can also use traditional python slice
         notation, where N:M means numbers N through M-1.
 
         For example, if your history contains (print using %hist -n )::
 
           44: x=1
           45: y=3
           46: z=x+y
           47: print x
           48: a=5
           49: print 'x',x,'y',y
 
         you can create a macro with lines 44 through 47 (included) and line 49
         called my_macro with::
 
           In [55]: %macro my_macro 44-47 49
 
         Now, typing `my_macro` (without quotes) will re-execute all this code
         in one pass.
 
         You don't need to give the line-numbers in order, and any given line
         number can appear multiple times. You can assemble macros with any
         lines from your input history in any order.
 
         The macro is a simple object which holds its value in an attribute,
         but IPython's display system checks for macros and executes them as
         code instead of printing them when you type their name.
 
         You can view a macro's contents by explicitly printing it with::
 
           print macro_name
 
         """
         opts,args = self.parse_options(parameter_s,'rq',mode='list')
         if not args:   # List existing macros
             return sorted(k for k,v in self.shell.user_ns.items() if isinstance(v, Macro))
         if len(args) == 1:
             raise UsageError(
                 "%macro insufficient args; usage '%macro name n1-n2 n3-4...")
         name, codefrom = args[0], " ".join(args[1:])
 
         #print 'rng',ranges  # dbg
         try:
             lines = self.shell.find_user_code(codefrom, 'r' in opts)
         except (ValueError, TypeError) as e:
             print(e.args[0])
             return
         macro = Macro(lines)
         self.shell.define_macro(name, macro)
         if not ( 'q' in opts) : 
             print('Macro `%s` created. To execute, type its name (without quotes).' % name)
             print('=== Macro contents: ===')
             print(macro, end=' ')
 
     @magic_arguments.magic_arguments()
     @magic_arguments.argument('output', type=str, default='', nargs='?',
         help="""The name of the variable in which to store output.
         This is a utils.io.CapturedIO object with stdout/err attributes
         for the text of the captured output.
 
         CapturedOutput also has a show() method for displaying the output,
         and __call__ as well, so you can use that to quickly display the
         output.
 
         If unspecified, captured output is discarded.
         """
     )
     @magic_arguments.argument('--no-stderr', action="store_true",
         help="""Don't capture stderr."""
     )
     @magic_arguments.argument('--no-stdout', action="store_true",
         help="""Don't capture stdout."""
     )
     @magic_arguments.argument('--no-display', action="store_true",
         help="""Don't capture IPython's rich display."""
     )
     @cell_magic
     def capture(self, line, cell):
         """run the cell, capturing stdout, stderr, and IPython's rich display() calls."""
         args = magic_arguments.parse_argstring(self.capture, line)
         out = not args.no_stdout
         err = not args.no_stderr
         disp = not args.no_display
         with capture_output(out, err, disp) as io:
             self.shell.run_cell(cell)
-        if args.output:
+        if DisplayHook.semicolon_at_end_of_expression(cell):
+            if args.output in self.shell.user_ns:
+                del self.shell.user_ns[args.output]
+        elif args.output:
             self.shell.user_ns[args.output] = io
 
 def parse_breakpoint(text, current_file):
     '''Returns (file, line) for file:line and (current_file, line) for line'''
     colon = text.find(':')
     if colon == -1:
         return current_file, int(text)
     else:
         return text[:colon], int(text[colon+1:])
     
 def _format_time(timespan, precision=3):
     """Formats the timespan in a human readable form"""
 
     if timespan >= 60.0:
         # we have more than a minute, format that in a human readable form
         # Idea from http://snipplr.com/view/5713/
         parts = [("d", 60*60*24),("h", 60*60),("min", 60), ("s", 1)]
         time = []
         leftover = timespan
         for suffix, length in parts:
             value = int(leftover / length)
             if value > 0:
                 leftover = leftover % length
                 time.append(u'%s%s' % (str(value), suffix))
             if leftover < 1:
                 break
         return " ".join(time)
 
     
     # Unfortunately the unicode 'micro' symbol can cause problems in
     # certain terminals.  
     # See bug: https://bugs.launchpad.net/ipython/+bug/348466
     # Try to prevent crashes by being more secure than it needs to
     # E.g. eclipse is able to print a µ, but has no sys.stdout.encoding set.
     units = [u"s", u"ms",u'us',"ns"] # the save value   
     if hasattr(sys.stdout, 'encoding') and sys.stdout.encoding:
         try:
             u'\xb5'.encode(sys.stdout.encoding)
             units = [u"s", u"ms",u'\xb5s',"ns"]
         except:
             pass
     scaling = [1, 1e3, 1e6, 1e9]
         
     if timespan > 0.0:
         order = min(-int(math.floor(math.log10(timespan)) // 3), 3)
     else:
         order = 3
     return u"%.*g %s" % (precision, timespan * scaling[order], units[order])

IPython/core/tests/test_magic.py

@@ -1,1512 +1,1531 b''
 # -*- coding: utf-8 -*-
 """Tests for various magic functions."""
 
 import gc
 import io
 import os
 import re
 import shlex
 import sys
 import warnings
 from importlib import invalidate_caches
 from io import StringIO
 from pathlib import Path
 from textwrap import dedent
 from unittest import TestCase, mock
 
 import pytest
 
 from IPython import get_ipython
 from IPython.core import magic
 from IPython.core.error import UsageError
 from IPython.core.magic import (
     Magics,
     cell_magic,
     line_magic,
     magics_class,
     register_cell_magic,
     register_line_magic,
 )
 from IPython.core.magics import code, execution, logging, osm, script
 from IPython.testing import decorators as dec
 from IPython.testing import tools as tt
 from IPython.utils.io import capture_output
 from IPython.utils.process import find_cmd
 from IPython.utils.tempdir import TemporaryDirectory, TemporaryWorkingDirectory
 from IPython.utils.syspathcontext import prepended_to_syspath
 
 from .test_debugger import PdbTestInput
 
 from tempfile import NamedTemporaryFile
 
 @magic.magics_class
 class DummyMagics(magic.Magics): pass
 
 def test_extract_code_ranges():
     instr = "1 3 5-6 7-9 10:15 17: :10 10- -13 :"
     expected = [
         (0, 1),
         (2, 3),
         (4, 6),
         (6, 9),
         (9, 14),
         (16, None),
         (None, 9),
         (9, None),
         (None, 13),
         (None, None),
     ]
     actual = list(code.extract_code_ranges(instr))
     assert actual == expected
 
 def test_extract_symbols():
     source = """import foo\na = 10\ndef b():\n    return 42\n\n\nclass A: pass\n\n\n"""
     symbols_args = ["a", "b", "A", "A,b", "A,a", "z"]
     expected = [([], ['a']),
                 (["def b():\n    return 42\n"], []),
                 (["class A: pass\n"], []),
                 (["class A: pass\n", "def b():\n    return 42\n"], []),
                 (["class A: pass\n"], ['a']),
                 ([], ['z'])]
     for symbols, exp in zip(symbols_args, expected):
         assert code.extract_symbols(source, symbols) == exp
 
 
 def test_extract_symbols_raises_exception_with_non_python_code():
     source = ("=begin A Ruby program :)=end\n"
               "def hello\n"
               "puts 'Hello world'\n"
               "end")
     with pytest.raises(SyntaxError):
         code.extract_symbols(source, "hello")
 
 
 def test_magic_not_found():
     # magic not found raises UsageError
     with pytest.raises(UsageError):
         _ip.run_line_magic("doesntexist", "")
 
     # ensure result isn't success when a magic isn't found
     result = _ip.run_cell('%doesntexist')
     assert isinstance(result.error_in_exec, UsageError)
 
 
 def test_cell_magic_not_found():
     # magic not found raises UsageError
     with pytest.raises(UsageError):
         _ip.run_cell_magic('doesntexist', 'line', 'cell')
 
     # ensure result isn't success when a magic isn't found
     result = _ip.run_cell('%%doesntexist')
     assert isinstance(result.error_in_exec, UsageError)
 
 
 def test_magic_error_status():
     def fail(shell):
         1/0
     _ip.register_magic_function(fail)
     result = _ip.run_cell('%fail')
     assert isinstance(result.error_in_exec, ZeroDivisionError)
 
 
 def test_config():
     """ test that config magic does not raise
     can happen if Configurable init is moved too early into
     Magics.__init__ as then a Config object will be registered as a
     magic.
     """
     ## should not raise.
     _ip.run_line_magic("config", "")
 
 
 def test_config_available_configs():
     """ test that config magic prints available configs in unique and
     sorted order. """
     with capture_output() as captured:
         _ip.run_line_magic("config", "")
 
     stdout = captured.stdout
     config_classes = stdout.strip().split('\n')[1:]
     assert config_classes == sorted(set(config_classes))
 
 def test_config_print_class():
     """ test that config with a classname prints the class's options. """
     with capture_output() as captured:
         _ip.run_line_magic("config", "TerminalInteractiveShell")
 
     stdout = captured.stdout
     assert re.match(
         "TerminalInteractiveShell.* options", stdout.splitlines()[0]
     ), f"{stdout}\n\n1st line of stdout not like 'TerminalInteractiveShell.* options'"
 
 
 def test_rehashx():
     # clear up everything
     _ip.alias_manager.clear_aliases()
     del _ip.db['syscmdlist']
 
     _ip.run_line_magic("rehashx", "")
     # Practically ALL ipython development systems will have more than 10 aliases
 
     assert len(_ip.alias_manager.aliases) > 10
     for name, cmd in _ip.alias_manager.aliases:
         # we must strip dots from alias names
         assert "." not in name
 
     # rehashx must fill up syscmdlist
     scoms = _ip.db['syscmdlist']
     assert len(scoms) > 10
 
 
 def test_magic_parse_options():
     """Test that we don't mangle paths when parsing magic options."""
     ip = get_ipython()
     path = 'c:\\x'
     m = DummyMagics(ip)
     opts = m.parse_options('-f %s' % path,'f:')[0]
     # argv splitting is os-dependent
     if os.name == 'posix':
         expected = 'c:x'
     else:
         expected = path
     assert opts["f"] == expected
 
 
 def test_magic_parse_long_options():
     """Magic.parse_options can handle --foo=bar long options"""
     ip = get_ipython()
     m = DummyMagics(ip)
     opts, _ = m.parse_options("--foo --bar=bubble", "a", "foo", "bar=")
     assert "foo" in opts
     assert "bar" in opts
     assert opts["bar"] == "bubble"
 
 
 def doctest_hist_f():
     """Test %hist -f with temporary filename.
 
     In [9]: import tempfile
 
     In [10]: tfile = tempfile.mktemp('.py','tmp-ipython-')
 
     In [11]: %hist -nl -f $tfile 3
 
     In [13]: import os; os.unlink(tfile)
     """
 
 
 def doctest_hist_op():
     """Test %hist -op
 
     In [1]: class b(float):
        ...:     pass
        ...:
 
     In [2]: class s(object):
        ...:     def __str__(self):
        ...:         return 's'
        ...:
 
     In [3]:
 
     In [4]: class r(b):
        ...:     def __repr__(self):
        ...:         return 'r'
        ...:
 
     In [5]: class sr(s,r): pass
        ...:
 
     In [6]:
 
     In [7]: bb=b()
 
     In [8]: ss=s()
 
     In [9]: rr=r()
 
     In [10]: ssrr=sr()
 
     In [11]: 4.5
     Out[11]: 4.5
 
     In [12]: str(ss)
     Out[12]: 's'
 
     In [13]:
 
     In [14]: %hist -op
     >>> class b:
     ...     pass
     ...
     >>> class s(b):
     ...     def __str__(self):
     ...         return 's'
     ...
     >>>
     >>> class r(b):
     ...     def __repr__(self):
     ...         return 'r'
     ...
     >>> class sr(s,r): pass
     >>>
     >>> bb=b()
     >>> ss=s()
     >>> rr=r()
     >>> ssrr=sr()
     >>> 4.5
     4.5
     >>> str(ss)
     's'
     >>>
     """
 
 def test_hist_pof():
     ip = get_ipython()
     ip.run_cell("1+2", store_history=True)
     #raise Exception(ip.history_manager.session_number)
     #raise Exception(list(ip.history_manager._get_range_session()))
     with TemporaryDirectory() as td:
         tf = os.path.join(td, 'hist.py')
         ip.run_line_magic('history', '-pof %s' % tf)
         assert os.path.isfile(tf)
 
 
 def test_macro():
     ip = get_ipython()
     ip.history_manager.reset()   # Clear any existing history.
     cmds = ["a=1", "def b():\n  return a**2", "print(a,b())"]
     for i, cmd in enumerate(cmds, start=1):
         ip.history_manager.store_inputs(i, cmd)
     ip.run_line_magic("macro", "test 1-3")
     assert ip.user_ns["test"].value == "\n".join(cmds) + "\n"
 
     # List macros
     assert "test" in ip.run_line_magic("macro", "")
 
 
 def test_macro_run():
     """Test that we can run a multi-line macro successfully."""
     ip = get_ipython()
     ip.history_manager.reset()
     cmds = ["a=10", "a+=1", "print(a)", "%macro test 2-3"]
     for cmd in cmds:
         ip.run_cell(cmd, store_history=True)
     assert ip.user_ns["test"].value == "a+=1\nprint(a)\n"
     with tt.AssertPrints("12"):
         ip.run_cell("test")
     with tt.AssertPrints("13"):
         ip.run_cell("test")
 
 
 def test_magic_magic():
     """Test %magic"""
     ip = get_ipython()
     with capture_output() as captured:
         ip.run_line_magic("magic", "")
 
     stdout = captured.stdout
     assert "%magic" in stdout
     assert "IPython" in stdout
     assert "Available" in stdout
 
 
 @dec.skipif_not_numpy
 def test_numpy_reset_array_undec():
     "Test '%reset array' functionality"
     _ip.ex("import numpy as np")
     _ip.ex("a = np.empty(2)")
     assert "a" in _ip.user_ns
     _ip.run_line_magic("reset", "-f array")
     assert "a" not in _ip.user_ns
 
 
 def test_reset_out():
     "Test '%reset out' magic"
     _ip.run_cell("parrot = 'dead'", store_history=True)
     # test '%reset -f out', make an Out prompt
     _ip.run_cell("parrot", store_history=True)
     assert "dead" in [_ip.user_ns[x] for x in ("_", "__", "___")]
     _ip.run_line_magic("reset", "-f out")
     assert "dead" not in [_ip.user_ns[x] for x in ("_", "__", "___")]
     assert len(_ip.user_ns["Out"]) == 0
 
 
 def test_reset_in():
     "Test '%reset in' magic"
     # test '%reset -f in'
     _ip.run_cell("parrot", store_history=True)
     assert "parrot" in [_ip.user_ns[x] for x in ("_i", "_ii", "_iii")]
     _ip.run_line_magic("reset", "-f in")
     assert "parrot" not in [_ip.user_ns[x] for x in ("_i", "_ii", "_iii")]
     assert len(set(_ip.user_ns["In"])) == 1
 
 
 def test_reset_dhist():
     "Test '%reset dhist' magic"
     _ip.run_cell("tmp = [d for d in _dh]")  # copy before clearing
     _ip.run_line_magic("cd", os.path.dirname(pytest.__file__))
     _ip.run_line_magic("cd", "-")
     assert len(_ip.user_ns["_dh"]) > 0
     _ip.run_line_magic("reset", "-f dhist")
     assert len(_ip.user_ns["_dh"]) == 0
     _ip.run_cell("_dh = [d for d in tmp]")  # restore
 
 
 def test_reset_in_length():
     "Test that '%reset in' preserves In[] length"
     _ip.run_cell("print 'foo'")
     _ip.run_cell("reset -f in")
     assert len(_ip.user_ns["In"]) == _ip.displayhook.prompt_count + 1
 
 
 class TestResetErrors(TestCase):
 
     def test_reset_redefine(self):
 
         @magics_class
         class KernelMagics(Magics):
               @line_magic
               def less(self, shell): pass
 
         _ip.register_magics(KernelMagics)
 
         with self.assertLogs() as cm:
             # hack, we want to just capture logs, but assertLogs fails if not
             # logs get produce.
             # so log one things we ignore.
             import logging as log_mod
             log = log_mod.getLogger()
             log.info('Nothing')
             # end hack.
             _ip.run_cell("reset -f")
 
         assert len(cm.output) == 1
         for out in cm.output:
             assert "Invalid alias" not in out
 
 def test_tb_syntaxerror():
     """test %tb after a SyntaxError"""
     ip = get_ipython()
     ip.run_cell("for")
 
     # trap and validate stdout
     save_stdout = sys.stdout
     try:
         sys.stdout = StringIO()
         ip.run_cell("%tb")
         out = sys.stdout.getvalue()
     finally:
         sys.stdout = save_stdout
     # trim output, and only check the last line
     last_line = out.rstrip().splitlines()[-1].strip()
     assert last_line == "SyntaxError: invalid syntax"
 
 
 def test_time():
     ip = get_ipython()
 
     with tt.AssertPrints("Wall time: "):
         ip.run_cell("%time None")
 
     ip.run_cell("def f(kmjy):\n"
                 "    %time print (2*kmjy)")
 
     with tt.AssertPrints("Wall time: "):
         with tt.AssertPrints("hihi", suppress=False):
             ip.run_cell("f('hi')")
 
 
 # ';' at the end of %time prevents instruction value to be printed.
 # This tests fix for #13837.
 def test_time_no_output_with_semicolon():
     ip = get_ipython()
 
     # Test %time cases
     with tt.AssertPrints(" 123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%time 123000+456")
 
     with tt.AssertNotPrints(" 123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%time 123000+456;")
 
     with tt.AssertPrints(" 123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%time 123000+456 # Comment")
 
     with tt.AssertNotPrints(" 123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%time 123000+456; # Comment")
 
     with tt.AssertPrints(" 123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%time 123000+456 # ;Comment")
 
     # Test %%time cases
     with tt.AssertPrints("123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%%time\n123000+456\n\n\n")
 
     with tt.AssertNotPrints("123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%%time\n123000+456;\n\n\n")
 
     with tt.AssertPrints("123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%%time\n123000+456  # Comment\n\n\n")
 
     with tt.AssertNotPrints("123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%%time\n123000+456;  # Comment\n\n\n")
 
     with tt.AssertPrints("123456"):
         with tt.AssertPrints("Wall time: ", suppress=False):
             with tt.AssertPrints("CPU times: ", suppress=False):
                 ip.run_cell("%%time\n123000+456  # ;Comment\n\n\n")
 
 
 def test_time_last_not_expression():
     ip.run_cell("%%time\n"
                 "var_1 = 1\n"
                 "var_2 = 2\n")
     assert ip.user_ns['var_1'] == 1
     del ip.user_ns['var_1']
     assert ip.user_ns['var_2'] == 2
     del ip.user_ns['var_2']
 
 
 @dec.skip_win32
 def test_time2():
     ip = get_ipython()
 
     with tt.AssertPrints("CPU times: user "):
         ip.run_cell("%time None")
 
 def test_time3():
     """Erroneous magic function calls, issue gh-3334"""
     ip = get_ipython()
     ip.user_ns.pop('run', None)
 
     with tt.AssertNotPrints("not found", channel='stderr'):
         ip.run_cell("%%time\n"
                     "run = 0\n"
                     "run += 1")
 
 def test_multiline_time():
     """Make sure last statement from time return a value."""
     ip = get_ipython()
     ip.user_ns.pop('run', None)
 
     ip.run_cell(
         dedent(
             """\
         %%time
         a = "ho"
         b = "hey"
         a+b
         """
         )
     )
     assert ip.user_ns_hidden["_"] == "hohey"
 
 
 def test_time_local_ns():
     """
     Test that local_ns is actually global_ns when running a cell magic
     """
     ip = get_ipython()
     ip.run_cell("%%time\n" "myvar = 1")
     assert ip.user_ns["myvar"] == 1
     del ip.user_ns["myvar"]
 
 
+# Test %%capture magic. Added to test issue #13926
+def test_capture():
+    ip = get_ipython()
+
+    # Test %%capture nominal case
+    ip.run_cell("%%capture abc\n1+2")
+    with tt.AssertPrints("True", suppress=False):
+        ip.run_cell("'abc' in locals()")
+    with tt.AssertPrints("True", suppress=False):
+        ip.run_cell("'outputs' in dir(abc)")
+    with tt.AssertPrints("3", suppress=False):
+        ip.run_cell("abc.outputs[0]")
+
+    # Test %%capture with ';' at end of expression
+    ip.run_cell("%%capture abc\n7+8;")
+    with tt.AssertPrints("False", suppress=False):
+        ip.run_cell("'abc' in locals()")
+
+
 def test_doctest_mode():
     "Toggle doctest_mode twice, it should be a no-op and run without error"
     _ip.run_line_magic("doctest_mode", "")
     _ip.run_line_magic("doctest_mode", "")
 
 
 def test_parse_options():
     """Tests for basic options parsing in magics."""
     # These are only the most minimal of tests, more should be added later.  At
     # the very least we check that basic text/unicode calls work OK.
     m = DummyMagics(_ip)
     assert m.parse_options("foo", "")[1] == "foo"
     assert m.parse_options("foo", "")[1] == "foo"
 
 
 def test_parse_options_preserve_non_option_string():
     """Test to assert preservation of non-option part of magic-block, while parsing magic options."""
     m = DummyMagics(_ip)
     opts, stmt = m.parse_options(
         " -n1  -r 13 _ = 314 + foo", "n:r:", preserve_non_opts=True
     )
     assert opts == {"n": "1", "r": "13"}
     assert stmt == "_ = 314 + foo"
 
 
 def test_run_magic_preserve_code_block():
     """Test to assert preservation of non-option part of magic-block, while running magic."""
     _ip.user_ns["spaces"] = []
     _ip.run_line_magic(
         "timeit", "-n1 -r1 spaces.append([s.count(' ') for s in ['document']])"
     )
     assert _ip.user_ns["spaces"] == [[0]]
 
 
 def test_dirops():
     """Test various directory handling operations."""
     # curpath = lambda :os.path.splitdrive(os.getcwd())[1].replace('\\','/')
     curpath = os.getcwd
     startdir = os.getcwd()
     ipdir = os.path.realpath(_ip.ipython_dir)
     try:
         _ip.run_line_magic("cd", '"%s"' % ipdir)
         assert curpath() == ipdir
         _ip.run_line_magic("cd", "-")
         assert curpath() == startdir
         _ip.run_line_magic("pushd", '"%s"' % ipdir)
         assert curpath() == ipdir
         _ip.run_line_magic("popd", "")
         assert curpath() == startdir
     finally:
         os.chdir(startdir)
 
 
 def test_cd_force_quiet():
     """Test OSMagics.cd_force_quiet option"""
     _ip.config.OSMagics.cd_force_quiet = True
     osmagics = osm.OSMagics(shell=_ip)
 
     startdir = os.getcwd()
     ipdir = os.path.realpath(_ip.ipython_dir)
 
     try:
         with tt.AssertNotPrints(ipdir):
             osmagics.cd('"%s"' % ipdir)
         with tt.AssertNotPrints(startdir):
             osmagics.cd('-')
     finally:
         os.chdir(startdir)
 
 
 def test_xmode():
     # Calling xmode three times should be a no-op
     xmode = _ip.InteractiveTB.mode
     for i in range(4):
         _ip.run_line_magic("xmode", "")
     assert _ip.InteractiveTB.mode == xmode
 
 def test_reset_hard():
     monitor = []
     class A(object):
         def __del__(self):
             monitor.append(1)
         def __repr__(self):
             return "<A instance>"
 
     _ip.user_ns["a"] = A()
     _ip.run_cell("a")
 
     assert monitor == []
     _ip.run_line_magic("reset", "-f")
     assert monitor == [1]
 
 class TestXdel(tt.TempFileMixin):
     def test_xdel(self):
         """Test that references from %run are cleared by xdel."""
         src = ("class A(object):\n"
                "    monitor = []\n"
                "    def __del__(self):\n"
                "        self.monitor.append(1)\n"
                "a = A()\n")
         self.mktmp(src)
         # %run creates some hidden references...
         _ip.run_line_magic("run", "%s" % self.fname)
         # ... as does the displayhook.
         _ip.run_cell("a")
 
         monitor = _ip.user_ns["A"].monitor
         assert monitor == []
 
         _ip.run_line_magic("xdel", "a")
 
         # Check that a's __del__ method has been called.
         gc.collect(0)
         assert monitor == [1]
 
 def doctest_who():
     """doctest for %who
 
     In [1]: %reset -sf
 
     In [2]: alpha = 123
 
     In [3]: beta = 'beta'
 
     In [4]: %who int
     alpha
 
     In [5]: %who str
     beta
 
     In [6]: %whos
     Variable   Type    Data/Info
     ----------------------------
     alpha      int     123
     beta       str     beta
 
     In [7]: %who_ls
     Out[7]: ['alpha', 'beta']
     """
 
 def test_whos():
     """Check that whos is protected against objects where repr() fails."""
     class A(object):
         def __repr__(self):
             raise Exception()
     _ip.user_ns['a'] = A()
     _ip.run_line_magic("whos", "")
 
 def doctest_precision():
     """doctest for %precision
 
     In [1]: f = get_ipython().display_formatter.formatters['text/plain']
 
     In [2]: %precision 5
     Out[2]: '%.5f'
 
     In [3]: f.float_format
     Out[3]: '%.5f'
 
     In [4]: %precision %e
     Out[4]: '%e'
 
     In [5]: f(3.1415927)
     Out[5]: '3.141593e+00'
     """
 
 def test_debug_magic():
     """Test debugging a small code with %debug
 
     In [1]: with PdbTestInput(['c']):
        ...:     %debug print("a b") #doctest: +ELLIPSIS
        ...:
     ...
     ipdb> c
     a b
     In [2]:
     """
 
 def test_psearch():
     with tt.AssertPrints("dict.fromkeys"):
         _ip.run_cell("dict.fr*?")
     with tt.AssertPrints("π.is_integer"):
         _ip.run_cell("π = 3.14;\nπ.is_integ*?")
 
 def test_timeit_shlex():
     """test shlex issues with timeit (#1109)"""
     _ip.ex("def f(*a,**kw): pass")
     _ip.run_line_magic("timeit", '-n1 "this is a bug".count(" ")')
     _ip.run_line_magic("timeit", '-r1 -n1 f(" ", 1)')
     _ip.run_line_magic("timeit", '-r1 -n1 f(" ", 1, " ", 2, " ")')
     _ip.run_line_magic("timeit", '-r1 -n1 ("a " + "b")')
     _ip.run_line_magic("timeit", '-r1 -n1 f("a " + "b")')
     _ip.run_line_magic("timeit", '-r1 -n1 f("a " + "b ")')
 
 
 def test_timeit_special_syntax():
     "Test %%timeit with IPython special syntax"
     @register_line_magic
     def lmagic(line):
         ip = get_ipython()
         ip.user_ns['lmagic_out'] = line
 
     # line mode test
     _ip.run_line_magic("timeit", "-n1 -r1 %lmagic my line")
     assert _ip.user_ns["lmagic_out"] == "my line"
     # cell mode test
     _ip.run_cell_magic("timeit", "-n1 -r1", "%lmagic my line2")
     assert _ip.user_ns["lmagic_out"] == "my line2"
 
 
 def test_timeit_return():
     """
     test whether timeit -o return object
     """
 
     res = _ip.run_line_magic('timeit','-n10 -r10 -o 1')
     assert(res is not None)
 
 def test_timeit_quiet():
     """
     test quiet option of timeit magic
     """
     with tt.AssertNotPrints("loops"):
         _ip.run_cell("%timeit -n1 -r1 -q 1")
 
 def test_timeit_return_quiet():
     with tt.AssertNotPrints("loops"):
         res = _ip.run_line_magic('timeit', '-n1 -r1 -q -o 1')
     assert (res is not None)
 
 def test_timeit_invalid_return():
     with pytest.raises(SyntaxError):
         _ip.run_line_magic('timeit', 'return')
 
 @dec.skipif(execution.profile is None)
 def test_prun_special_syntax():
     "Test %%prun with IPython special syntax"
     @register_line_magic
     def lmagic(line):
         ip = get_ipython()
         ip.user_ns['lmagic_out'] = line
 
     # line mode test
     _ip.run_line_magic("prun", "-q %lmagic my line")
     assert _ip.user_ns["lmagic_out"] == "my line"
     # cell mode test
     _ip.run_cell_magic("prun", "-q", "%lmagic my line2")
     assert _ip.user_ns["lmagic_out"] == "my line2"
 
 
 @dec.skipif(execution.profile is None)
 def test_prun_quotes():
     "Test that prun does not clobber string escapes (GH #1302)"
     _ip.magic(r"prun -q x = '\t'")
     assert _ip.user_ns["x"] == "\t"
 
 
 def test_extension():
     # Debugging information for failures of this test
     print('sys.path:')
     for p in sys.path:
         print(' ', p)
     print('CWD', os.getcwd())
 
     pytest.raises(ImportError, _ip.magic, "load_ext daft_extension")
     daft_path = os.path.join(os.path.dirname(__file__), "daft_extension")
     sys.path.insert(0, daft_path)
     try:
         _ip.user_ns.pop('arq', None)
         invalidate_caches()   # Clear import caches
         _ip.run_line_magic("load_ext", "daft_extension")
         assert _ip.user_ns["arq"] == 185
         _ip.run_line_magic("unload_ext", "daft_extension")
         assert 'arq' not in _ip.user_ns
     finally:
         sys.path.remove(daft_path)
 
 
 def test_notebook_export_json():
     pytest.importorskip("nbformat")
     _ip = get_ipython()
     _ip.history_manager.reset()   # Clear any existing history.
     cmds = ["a=1", "def b():\n  return a**2", "print('noël, été', b())"]
     for i, cmd in enumerate(cmds, start=1):
         _ip.history_manager.store_inputs(i, cmd)
     with TemporaryDirectory() as td:
         outfile = os.path.join(td, "nb.ipynb")
         _ip.run_line_magic("notebook", "%s" % outfile)
 
 
 class TestEnv(TestCase):
 
     def test_env(self):
         env = _ip.run_line_magic("env", "")
         self.assertTrue(isinstance(env, dict))
 
     def test_env_secret(self):
         env = _ip.run_line_magic("env", "")
         hidden = "<hidden>"
         with mock.patch.dict(
             os.environ,
             {
                 "API_KEY": "abc123",
                 "SECRET_THING": "ssshhh",
                 "JUPYTER_TOKEN": "",
                 "VAR": "abc"
             }
         ):
             env = _ip.run_line_magic("env", "")
         assert env["API_KEY"] == hidden
         assert env["SECRET_THING"] == hidden
         assert env["JUPYTER_TOKEN"] == hidden
         assert env["VAR"] == "abc"
 
     def test_env_get_set_simple(self):
         env = _ip.run_line_magic("env", "var val1")
         self.assertEqual(env, None)
         self.assertEqual(os.environ["var"], "val1")
         self.assertEqual(_ip.run_line_magic("env", "var"), "val1")
         env = _ip.run_line_magic("env", "var=val2")
         self.assertEqual(env, None)
         self.assertEqual(os.environ['var'], 'val2')
 
     def test_env_get_set_complex(self):
         env = _ip.run_line_magic("env", "var 'val1 '' 'val2")
         self.assertEqual(env, None)
         self.assertEqual(os.environ['var'], "'val1 '' 'val2")
         self.assertEqual(_ip.run_line_magic("env", "var"), "'val1 '' 'val2")
         env = _ip.run_line_magic("env", 'var=val2 val3="val4')
         self.assertEqual(env, None)
         self.assertEqual(os.environ['var'], 'val2 val3="val4')
 
     def test_env_set_bad_input(self):
         self.assertRaises(UsageError, lambda: _ip.run_line_magic("set_env", "var"))
 
     def test_env_set_whitespace(self):
         self.assertRaises(UsageError, lambda: _ip.run_line_magic("env", "var A=B"))
 
 
 class CellMagicTestCase(TestCase):
 
     def check_ident(self, magic):
         # Manually called, we get the result
         out = _ip.run_cell_magic(magic, "a", "b")
         assert out == ("a", "b")
         # Via run_cell, it goes into the user's namespace via displayhook
         _ip.run_cell("%%" + magic + " c\nd\n")
         assert _ip.user_ns["_"] == ("c", "d\n")
 
     def test_cell_magic_func_deco(self):
         "Cell magic using simple decorator"
         @register_cell_magic
         def cellm(line, cell):
             return line, cell
 
         self.check_ident('cellm')
 
     def test_cell_magic_reg(self):
         "Cell magic manually registered"
         def cellm(line, cell):
             return line, cell
 
         _ip.register_magic_function(cellm, 'cell', 'cellm2')
         self.check_ident('cellm2')
 
     def test_cell_magic_class(self):
         "Cell magics declared via a class"
         @magics_class
         class MyMagics(Magics):
 
             @cell_magic
             def cellm3(self, line, cell):
                 return line, cell
 
         _ip.register_magics(MyMagics)
         self.check_ident('cellm3')
 
     def test_cell_magic_class2(self):
         "Cell magics declared via a class, #2"
         @magics_class
         class MyMagics2(Magics):
 
             @cell_magic('cellm4')
             def cellm33(self, line, cell):
                 return line, cell
 
         _ip.register_magics(MyMagics2)
         self.check_ident('cellm4')
         # Check that nothing is registered as 'cellm33'
         c33 = _ip.find_cell_magic('cellm33')
         assert c33 == None
 
 def test_file():
     """Basic %%writefile"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, "file1")
         ip.run_cell_magic(
             "writefile",
             fname,
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line2" in s
 
 
 @dec.skip_win32
 def test_file_single_quote():
     """Basic %%writefile with embedded single quotes"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, "'file1'")
         ip.run_cell_magic(
             "writefile",
             fname,
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line2" in s
 
 
 @dec.skip_win32
 def test_file_double_quote():
     """Basic %%writefile with embedded double quotes"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, '"file1"')
         ip.run_cell_magic(
             "writefile",
             fname,
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line2" in s
 
 
 def test_file_var_expand():
     """%%writefile $filename"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, "file1")
         ip.user_ns["filename"] = fname
         ip.run_cell_magic(
             "writefile",
             "$filename",
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line2" in s
 
 
 def test_file_unicode():
     """%%writefile with unicode cell"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, 'file1')
         ip.run_cell_magic("writefile", fname, u'\n'.join([
             u'liné1',
             u'liné2',
         ]))
         with io.open(fname, encoding='utf-8') as f:
             s = f.read()
         assert "liné1\n" in s
         assert "liné2" in s
 
 
 def test_file_amend():
     """%%writefile -a amends files"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, "file2")
         ip.run_cell_magic(
             "writefile",
             fname,
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         ip.run_cell_magic(
             "writefile",
             "-a %s" % fname,
             "\n".join(
                 [
                     "line3",
                     "line4",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line3\n" in s
 
 
 def test_file_spaces():
     """%%file with spaces in filename"""
     ip = get_ipython()
     with TemporaryWorkingDirectory() as td:
         fname = "file name"
         ip.run_cell_magic(
             "file",
             '"%s"' % fname,
             "\n".join(
                 [
                     "line1",
                     "line2",
                 ]
             ),
         )
         s = Path(fname).read_text(encoding="utf-8")
         assert "line1\n" in s
         assert "line2" in s
 
 
 def test_script_config():
     ip = get_ipython()
     ip.config.ScriptMagics.script_magics = ['whoda']
     sm = script.ScriptMagics(shell=ip)
     assert "whoda" in sm.magics["cell"]
 
 
 def test_script_out():
     ip = get_ipython()
     ip.run_cell_magic("script", f"--out output {sys.executable}", "print('hi')")
     assert ip.user_ns["output"].strip() == "hi"
 
 
 def test_script_err():
     ip = get_ipython()
     ip.run_cell_magic(
         "script",
         f"--err error {sys.executable}",
         "import sys; print('hello', file=sys.stderr)",
     )
     assert ip.user_ns["error"].strip() == "hello"
 
 
 def test_script_out_err():
     ip = get_ipython()
     ip.run_cell_magic(
         "script",
         f"--out output --err error {sys.executable}",
         "\n".join(
             [
                 "import sys",
                 "print('hi')",
                 "print('hello', file=sys.stderr)",
             ]
         ),
     )
     assert ip.user_ns["output"].strip() == "hi"
     assert ip.user_ns["error"].strip() == "hello"
 
 
 async def test_script_bg_out():
     ip = get_ipython()
     ip.run_cell_magic("script", f"--bg --out output {sys.executable}", "print('hi')")
     assert (await ip.user_ns["output"].read()).strip() == b"hi"
     assert ip.user_ns["output"].at_eof()
 
 
 async def test_script_bg_err():
     ip = get_ipython()
     ip.run_cell_magic(
         "script",
         f"--bg --err error {sys.executable}",
         "import sys; print('hello', file=sys.stderr)",
     )
     assert (await ip.user_ns["error"].read()).strip() == b"hello"
     assert ip.user_ns["error"].at_eof()
 
 
 async def test_script_bg_out_err():
     ip = get_ipython()
     ip.run_cell_magic(
         "script",
         f"--bg --out output --err error {sys.executable}",
         "\n".join(
             [
                 "import sys",
                 "print('hi')",
                 "print('hello', file=sys.stderr)",
             ]
         ),
     )
     assert (await ip.user_ns["output"].read()).strip() == b"hi"
     assert (await ip.user_ns["error"].read()).strip() == b"hello"
     assert ip.user_ns["output"].at_eof()
     assert ip.user_ns["error"].at_eof()
 
 
 async def test_script_bg_proc():
     ip = get_ipython()
     ip.run_cell_magic(
         "script",
         f"--bg --out output --proc p {sys.executable}",
         "\n".join(
             [
                 "import sys",
                 "print('hi')",
                 "print('hello', file=sys.stderr)",
             ]
         ),
     )
     p = ip.user_ns["p"]
     await p.wait()
     assert p.returncode == 0
     assert (await p.stdout.read()).strip() == b"hi"
     # not captured, so empty
     assert (await p.stderr.read()) == b""
     assert p.stdout.at_eof()
     assert p.stderr.at_eof()
 
 
 def test_script_defaults():
     ip = get_ipython()
     for cmd in ['sh', 'bash', 'perl', 'ruby']:
         try:
             find_cmd(cmd)
         except Exception:
             pass
         else:
             assert cmd in ip.magics_manager.magics["cell"]
 
 
 @magics_class
 class FooFoo(Magics):
     """class with both %foo and %%foo magics"""
     @line_magic('foo')
     def line_foo(self, line):
         "I am line foo"
         pass
 
     @cell_magic("foo")
     def cell_foo(self, line, cell):
         "I am cell foo, not line foo"
         pass
 
 def test_line_cell_info():
     """%%foo and %foo magics are distinguishable to inspect"""
     ip = get_ipython()
     ip.magics_manager.register(FooFoo)
     oinfo = ip.object_inspect("foo")
     assert oinfo["found"] is True
     assert oinfo["ismagic"] is True
 
     oinfo = ip.object_inspect("%%foo")
     assert oinfo["found"] is True
     assert oinfo["ismagic"] is True
     assert oinfo["docstring"] == FooFoo.cell_foo.__doc__
 
     oinfo = ip.object_inspect("%foo")
     assert oinfo["found"] is True
     assert oinfo["ismagic"] is True
     assert oinfo["docstring"] == FooFoo.line_foo.__doc__
 
 
 def test_multiple_magics():
     ip = get_ipython()
     foo1 = FooFoo(ip)
     foo2 = FooFoo(ip)
     mm = ip.magics_manager
     mm.register(foo1)
     assert mm.magics["line"]["foo"].__self__ is foo1
     mm.register(foo2)
     assert mm.magics["line"]["foo"].__self__ is foo2
 
 
 def test_alias_magic():
     """Test %alias_magic."""
     ip = get_ipython()
     mm = ip.magics_manager
 
     # Basic operation: both cell and line magics are created, if possible.
     ip.run_line_magic("alias_magic", "timeit_alias timeit")
     assert "timeit_alias" in mm.magics["line"]
     assert "timeit_alias" in mm.magics["cell"]
 
     # --cell is specified, line magic not created.
     ip.run_line_magic("alias_magic", "--cell timeit_cell_alias timeit")
     assert "timeit_cell_alias" not in mm.magics["line"]
     assert "timeit_cell_alias" in mm.magics["cell"]
 
     # Test that line alias is created successfully.
     ip.run_line_magic("alias_magic", "--line env_alias env")
     assert ip.run_line_magic("env", "") == ip.run_line_magic("env_alias", "")
 
     # Test that line alias with parameters passed in is created successfully.
     ip.run_line_magic(
         "alias_magic", "--line history_alias history --params " + shlex.quote("3")
     )
     assert "history_alias" in mm.magics["line"]
 
 
 def test_save():
     """Test %save."""
     ip = get_ipython()
     ip.history_manager.reset()   # Clear any existing history.
     cmds = ["a=1", "def b():\n  return a**2", "print(a, b())"]
     for i, cmd in enumerate(cmds, start=1):
         ip.history_manager.store_inputs(i, cmd)
     with TemporaryDirectory() as tmpdir:
         file = os.path.join(tmpdir, "testsave.py")
         ip.run_line_magic("save", "%s 1-10" % file)
         content = Path(file).read_text(encoding="utf-8")
         assert content.count(cmds[0]) == 1
         assert "coding: utf-8" in content
         ip.run_line_magic("save", "-a %s 1-10" % file)
         content = Path(file).read_text(encoding="utf-8")
         assert content.count(cmds[0]) == 2
         assert "coding: utf-8" in content
 
 
 def test_save_with_no_args():
     ip = get_ipython()
     ip.history_manager.reset()  # Clear any existing history.
     cmds = ["a=1", "def b():\n    return a**2", "print(a, b())", "%save"]
     for i, cmd in enumerate(cmds, start=1):
         ip.history_manager.store_inputs(i, cmd)
 
     with TemporaryDirectory() as tmpdir:
         path = os.path.join(tmpdir, "testsave.py")
         ip.run_line_magic("save", path)
         content = Path(path).read_text(encoding="utf-8")
         expected_content = dedent(
             """\
             # coding: utf-8
             a=1
             def b():
                 return a**2
             print(a, b())
             """
         )
         assert content == expected_content
 
 
 def test_store():
     """Test %store."""
     ip = get_ipython()
     ip.run_line_magic('load_ext', 'storemagic')
 
     # make sure the storage is empty
     ip.run_line_magic("store", "-z")
     ip.user_ns["var"] = 42
     ip.run_line_magic("store", "var")
     ip.user_ns["var"] = 39
     ip.run_line_magic("store", "-r")
     assert ip.user_ns["var"] == 42
 
     ip.run_line_magic("store", "-d var")
     ip.user_ns["var"] = 39
     ip.run_line_magic("store", "-r")
     assert ip.user_ns["var"] == 39
 
 
 def _run_edit_test(arg_s, exp_filename=None,
                         exp_lineno=-1,
                         exp_contents=None,
                         exp_is_temp=None):
     ip = get_ipython()
     M = code.CodeMagics(ip)
     last_call = ['','']
     opts,args = M.parse_options(arg_s,'prxn:')
     filename, lineno, is_temp = M._find_edit_target(ip, args, opts, last_call)
 
     if exp_filename is not None:
         assert exp_filename == filename
     if exp_contents is not None:
         with io.open(filename, 'r', encoding='utf-8') as f:
             contents = f.read()
         assert exp_contents == contents
     if exp_lineno != -1:
         assert exp_lineno == lineno
     if exp_is_temp is not None:
         assert exp_is_temp == is_temp
 
 
 def test_edit_interactive():
     """%edit on interactively defined objects"""
     ip = get_ipython()
     n = ip.execution_count
     ip.run_cell("def foo(): return 1", store_history=True)
 
     with pytest.raises(code.InteractivelyDefined) as e:
         _run_edit_test("foo")
     assert e.value.index == n
 
 
 def test_edit_cell():
     """%edit [cell id]"""
     ip = get_ipython()
 
     ip.run_cell("def foo(): return 1", store_history=True)
 
     # test
     _run_edit_test("1", exp_contents=ip.user_ns['In'][1], exp_is_temp=True)
 
 def test_edit_fname():
     """%edit file"""
     # test
     _run_edit_test("test file.py", exp_filename="test file.py")
 
 def test_bookmark():
     ip = get_ipython()
     ip.run_line_magic('bookmark', 'bmname')
     with tt.AssertPrints('bmname'):
         ip.run_line_magic('bookmark', '-l')
     ip.run_line_magic('bookmark', '-d bmname')
 
 def test_ls_magic():
     ip = get_ipython()
     json_formatter = ip.display_formatter.formatters['application/json']
     json_formatter.enabled = True
     lsmagic = ip.run_line_magic("lsmagic", "")
     with warnings.catch_warnings(record=True) as w:
         j = json_formatter(lsmagic)
     assert sorted(j) == ["cell", "line"]
     assert w == []  # no warnings
 
 
 def test_strip_initial_indent():
     def sii(s):
         lines = s.splitlines()
         return '\n'.join(code.strip_initial_indent(lines))
 
     assert sii("  a = 1\nb = 2") == "a = 1\nb = 2"
     assert sii("  a\n    b\nc") == "a\n  b\nc"
     assert sii("a\n  b") == "a\n  b"
 
 def test_logging_magic_quiet_from_arg():
     _ip.config.LoggingMagics.quiet = False
     lm = logging.LoggingMagics(shell=_ip)
     with TemporaryDirectory() as td:
         try:
             with tt.AssertNotPrints(re.compile("Activating.*")):
                 lm.logstart('-q {}'.format(
                         os.path.join(td, "quiet_from_arg.log")))
         finally:
             _ip.logger.logstop()
 
 def test_logging_magic_quiet_from_config():
     _ip.config.LoggingMagics.quiet = True
     lm = logging.LoggingMagics(shell=_ip)
     with TemporaryDirectory() as td:
         try:
             with tt.AssertNotPrints(re.compile("Activating.*")):
                 lm.logstart(os.path.join(td, "quiet_from_config.log"))
         finally:
             _ip.logger.logstop()
 
 
 def test_logging_magic_not_quiet():
     _ip.config.LoggingMagics.quiet = False
     lm = logging.LoggingMagics(shell=_ip)
     with TemporaryDirectory() as td:
         try:
             with tt.AssertPrints(re.compile("Activating.*")):
                 lm.logstart(os.path.join(td, "not_quiet.log"))
         finally:
             _ip.logger.logstop()
 
 
 def test_time_no_var_expand():
     _ip.user_ns["a"] = 5
     _ip.user_ns["b"] = []
     _ip.run_line_magic("time", 'b.append("{a}")')
     assert _ip.user_ns["b"] == ["{a}"]
 
 
 # this is slow, put at the end for local testing.
 def test_timeit_arguments():
     "Test valid timeit arguments, should not cause SyntaxError (GH #1269)"
     _ip.run_line_magic("timeit", "-n1 -r1 a=('#')")
 
 
 MINIMAL_LAZY_MAGIC = """
 from IPython.core.magic import (
     Magics,
     magics_class,
     line_magic,
     cell_magic,
 )
 
 
 @magics_class
 class LazyMagics(Magics):
     @line_magic
     def lazy_line(self, line):
         print("Lazy Line")
 
     @cell_magic
     def lazy_cell(self, line, cell):
         print("Lazy Cell")
 
 
 def load_ipython_extension(ipython):
     ipython.register_magics(LazyMagics)
 """
 
 
 def test_lazy_magics():
     with pytest.raises(UsageError):
         ip.run_line_magic("lazy_line", "")
 
     startdir = os.getcwd()
 
     with TemporaryDirectory() as tmpdir:
         with prepended_to_syspath(tmpdir):
             ptempdir = Path(tmpdir)
             tf = ptempdir / "lazy_magic_module.py"
             tf.write_text(MINIMAL_LAZY_MAGIC)
             ip.magics_manager.register_lazy("lazy_line", Path(tf.name).name[:-3])
             with tt.AssertPrints("Lazy Line"):
                 ip.run_line_magic("lazy_line", "")
 
 
 TEST_MODULE = """
 print('Loaded my_tmp')
 if __name__ == "__main__":
     print('I just ran a script')
 """
 
 def test_run_module_from_import_hook():
     "Test that a module can be loaded via an import hook"
     with TemporaryDirectory() as tmpdir:
         fullpath = os.path.join(tmpdir, "my_tmp.py")
         Path(fullpath).write_text(TEST_MODULE, encoding="utf-8")
 
         import importlib.abc
         import importlib.util
 
         class MyTempImporter(importlib.abc.MetaPathFinder, importlib.abc.SourceLoader):
             def find_spec(self, fullname, path, target=None):
                 if fullname == "my_tmp":
                     return importlib.util.spec_from_loader(fullname, self)
 
             def get_filename(self, fullname):
                 assert fullname == "my_tmp"
                 return fullpath
 
             def get_data(self, path):
                 assert Path(path).samefile(fullpath)
                 return Path(fullpath).read_text(encoding="utf-8")
 
         sys.meta_path.insert(0, MyTempImporter())
 
         with capture_output() as captured:
             _ip.run_line_magic("run", "-m my_tmp")
             _ip.run_cell("import my_tmp")
 
         output = "Loaded my_tmp\nI just ran a script\nLoaded my_tmp\n"
         assert output == captured.stdout
 
         sys.meta_path.pop(0)