From 93d13d63200bdbbca71079e5aa9161453ce3afbb 2021-12-10 17:41:29 From: Matthias Bussonnier Date: 2021-12-10 17:41:29 Subject: [PATCH] vmove to version8.rst --- diff --git a/docs/source/whatsnew/development.rst b/docs/source/whatsnew/development.rst index 5ae9b4e..0f628a7 100644 --- a/docs/source/whatsnew/development.rst +++ b/docs/source/whatsnew/development.rst @@ -22,430 +22,9 @@ Need to be updated: pr/* -IPython 8.0 is bringing a large number of new features and improvements to both the -user of the terminal and of the kernel via Jupyter. The removal of compatibility -with older version of Python is also the opportunity to do a couple of -performance improvement in particular with respect to startup time. -The 8.x branch started diverging from its predecessor around IPython 7.12 -(January 2020). - -This release contains 250+ Pull Requests, in addition to many of the features -and backports that have made it to the 7.x branch. All PRs that went into this -released are properly tagged with the 8.0 milestone if you wish to have a more -in depth look at the changes. - -Please fell free to send pull-requests to updates those notes after release, -I have likely forgotten a few things reviewing 250+ PRs. - -Dependencies changes/downstream packaging ------------------------------------------ - -Note that most of our building step have been changes to be (mostly) declarative -and follow PEP 517, we are trying to completely remove ``setup.py`` (:ghpull:`13238`) and are -looking for help to do so. - - - Minimum supported ``traitlets`` version if now 5+ - - we now require ``stack_data`` - - Minimal Python is now 3.8 - - ``nose`` is not a testing requirement anymore - - ``pytest`` replaces nose. - - ``iptest``/``iptest3`` cli entrypoints do not exists anymore. - - minimum officially support ``numpy`` version has been bumped, but this should - not have much effect on packaging. - - -Deprecation and removal ------------------------ - -We removed almost all features, arguments, functions, and modules that were -marked as deprecated between IPython 1.0 and 5.0. As reminder 5.0 was released -in 2016, and 1.0 in 2013. Last release of the 5 branch was 5.10.0, in may 2020. -The few remaining deprecated features we left have better deprecation warnings -or have been turned into explicit errors for better error messages. - -I will use this occasion to add the following requests to anyone emitting a -deprecation warning: - - - Please at at least ``stacklevel=2`` so that the warning is emitted into the - caller context, and not the callee one. - - Please add **since which version** something is deprecated. - -As a side note it is much easier to deal with conditional comparing to versions -numbers than ``try/except`` when a functionality change with version. - -I won't list all the removed features here, but modules like ``IPython.kernel``, -which was just a shim module around ``ipykernel`` for the past 8 years have been -remove, and so many other similar things that pre-date the name **Jupyter** -itself. - -We no longer need to add ``IPyhton.extensions`` to the PYTHONPATH because that is being -handled by ``load_extension``. - -We are also removing ``Cythonmagic``, ``sympyprinting`` and ``rmagic`` as they are now in -other packages and no longer need to be inside IPython. - - -Documentation -------------- - -Majority of our docstrings have now been reformatted and automatically fixed by -the experimental `Vélin `_ project, to conform -to numpydoc. - -Type annotations ----------------- - -While IPython itself is highly dynamic and can't be completely typed, many of -the function now have type annotation, and part of the codebase and now checked -by mypy. - - -Featured changes ----------------- - -Here is a features list of changes in IPython 8.0. This is of course non-exhaustive. -Please note as well that many features have been added in the 7.x branch as well -(and hence why you want to read the 7.x what's new notes), in particular -features contributed by QuantStack (with respect to debugger protocol, and Xeus -Python), as well as many debugger features that I was please to implement as -part of my work at QuanSight and Sponsored by DE Shaw. - -Better Tracebacks -~~~~~~~~~~~~~~~~~ - -The first on is the integration of the ``stack_data`` package; -which provide smarter informations in traceback; in particular it will highlight -the AST node where an error occurs which can help to quickly narrow down errors. - -For example in the following snippet:: - - def foo(i): - x = [[[0]]] - return x[0][i][0] - - - def bar(): - return foo(0) + foo( - 1 - ) + foo(2) - - -Calling ``bar()`` would raise an ``IndexError`` on the return line of ``foo``, -IPython 8.0 is capable of telling you, where the index error occurs:: - - - IndexError - Input In [2], in - ----> 1 bar() - ^^^^^ - - Input In [1], in bar() - 6 def bar(): - ----> 7 return foo(0) + foo( - ^^^^ - 8 1 - ^^^^^^^^ - 9 ) + foo(2) - ^^^^ - - Input In [1], in foo(i) - 1 def foo(i): - 2 x = [[[0]]] - ----> 3 return x[0][i][0] - ^^^^^^^ - -Corresponding location marked here with ``^`` will show up highlighted in -terminal and notebooks. - - -Autosuggestons -~~~~~~~~~~~~~~ - -Autosuggestion is a very useful feature available in `fish `__, `zsh `__, and `prompt-toolkit `__. - -`Ptpython `__ allows users to enable this feature in -`ptpython/config.py `__. - -This feature allows users to accept autosuggestions with ctrl e, ctrl f, -or right arrow as described below. - -1. Start ipython - -.. image:: ../_images/8.0/auto_suggest_1_prompt_no_text.png - -2. Run ``print("hello")`` - -.. image:: ../_images/8.0/auto_suggest_2_print_hello_suggest.png - -3. start typing ``print`` again to see the autosuggestion - -.. image:: ../_images/8.0/auto_suggest_3_print_hello_suggest.png - -4. Press ``ctrl-f``, or ``ctrl-e``, or ``right-arrow`` to accept the suggestion - -.. image:: ../_images/8.0/auto_suggest_4_print_hello.png - -You can also complete word by word: - -1. Run ``def say_hello(): print("hello")`` - -.. image:: ../_images/8.0/auto_suggest_second_prompt.png - -2. Start typing the first letter if ``def`` to see the autosuggestion - -.. image:: ../_images/8.0/auto_suggest_d_phantom.png - -3. Press ``alt-f`` (or ``escape`` followed by ``f``), to accept the first word of the suggestion - -.. image:: ../_images/8.0/auto_suggest_def_phantom.png - -Importantly, this feature does not interfere with tab completion: - -1. After running ``def say_hello(): print("hello")``, press d - -.. image:: ../_images/8.0/auto_suggest_d_phantom.png - -2. Press Tab to start tab completion - -.. image:: ../_images/8.0/auto_suggest_d_completions.png - -3A. Press Tab again to select the first option - -.. image:: ../_images/8.0/auto_suggest_def_completions.png - -3B. Press ``alt f`` (``escape``, ``f``) to accept to accept the first word of the suggestion - -.. image:: ../_images/8.0/auto_suggest_def_phantom.png - -3C. Press ``ctrl-f`` or ``ctrl-e`` to accept the entire suggestion - -.. image:: ../_images/8.0/auto_suggest_match_parens.png - - -Currently, autosuggestions are only shown in the emacs or vi insert editing modes: - -- The ctrl e, ctrl f, and alt f shortcuts work by default in emacs mode. -- To use these shortcuts in vi insert mode, you will have to create `custom keybindings in your config.py `__. - - -Show pinfo information in ipdb using "?" and "??" -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -In IPDB, it is now possible to show the information about an object using "?" -and "??", in much the same way it can be done when using the IPython prompt:: - - ipdb> partial? - Init signature: partial(self, /, *args, **kwargs) - Docstring: - partial(func, *args, **keywords) - new function with partial application - of the given arguments and keywords. - File: ~/.pyenv/versions/3.8.6/lib/python3.8/functools.py - Type: type - Subclasses: - -Previously, ``pinfo`` or ``pinfo2`` command had to be used for this purpose. - - -Autoreload 3 feature -~~~~~~~~~~~~~~~~~~~~ - -Example: When an IPython session is ran with the 'autoreload' extension loaded, -you will now have the option '3' to select which means the following: - - 1. replicate all functionality from option 2 - 2. autoload all new funcs/classes/enums/globals from the module when they are added - 3. autoload all newly imported funcs/classes/enums/globals from external modules - -Try ``%autoreload 3`` in an IPython session after running ``%load_ext autoreload`` - -For more information please see the following unit test : ``extensions/tests/test_autoreload.py:test_autoload_newly_added_objects`` - - - - -History Range Glob feature -~~~~~~~~~~~~~~~~~~~~~~~~~~ - -Previously, when using ``%history``, users could specify either -a range of sessions and lines, for example: - -.. code-block:: python - - ~8/1-~6/5 # see history from the first line of 8 sessions ago, - # to the fifth line of 6 sessions ago.`` - -Or users could specify a glob pattern: - -.. code-block:: python - - -g # glob ALL history for the specified pattern. - -However users could *not* specify both. - -If a user *did* specify both a range and a glob pattern, -then the glob pattern would be used (globbing *all* history) *and the range would be ignored*. - -With this enhancement, if a user specifies both a range and a glob pattern, then the glob pattern will be applied to the specified range of history. - -Don't start a multi line cell with sunken parenthesis -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -From now on IPython will not ask for the next line of input when given a single -line with more closing than opening brackets. For example, this means that if -you (mis)type ``]]`` instead of ``[]``, a ``SyntaxError`` will show up, instead of -the ``...:`` prompt continuation. - -IPython shell for ipdb interact -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -The ipdb ``interact`` starts an IPython shell instead of Python's built-in ``code.interact()``. - -Automatic Vi prompt stripping -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -When pasting code into IPython, it will strip the leading prompt characters if -there are any. For example, you can paste the following code into the console - -it will still work, even though each line is prefixed with prompts (`In`, -`Out`):: - - In [1]: 2 * 2 == 4 - Out[1]: True - - In [2]: print("This still works as pasted") - - -Previously, this was not the case for the Vi-mode prompts:: - - In [1]: [ins] In [13]: 2 * 2 == 4 - ...: Out[13]: True - ...: - File "", line 1 - [ins] In [13]: 2 * 2 == 4 - ^ - SyntaxError: invalid syntax - -This is now fixed, and Vi prompt prefixes - ``[ins]`` and ``[nav]`` - are -skipped just as the normal ``In`` would be. - -IPython shell can be started in the Vi mode using ``ipython --TerminalInteractiveShell.editing_mode=vi``, -You should be able to change mode dynamically with ``%config TerminalInteractiveShell.editing_mode='vi'`` - -Empty History Ranges -~~~~~~~~~~~~~~~~~~~~ - -A number of magics that take history ranges can now be used with an empty -range. These magics are: - - * ``%save`` - * ``%load`` - * ``%pastebin`` - * ``%pycat`` - -Using them this way will make them take the history of the current session up -to the point of the magic call (such that the magic itself will not be -included). - -Therefore it is now possible to save the whole history to a file using simple -``%save ``, load and edit it using ``%load`` (makes for a nice usage -when followed with :kbd:`F2`), send it to dpaste.org using ``%pastebin``, or -view the whole thing syntax-highlighted with a single ``%pycat``. - -Traceback improvements -~~~~~~~~~~~~~~~~~~~~~~ - - -Previously, error tracebacks for errors happening in code cells were showing a hash, the one used for compiling the Python AST:: - - In [1]: def foo(): - ...: return 3 / 0 - ...: - - In [2]: foo() - --------------------------------------------------------------------------- - ZeroDivisionError Traceback (most recent call last) - in - ----> 1 foo() - - in foo() - 1 def foo(): - ----> 2 return 3 / 0 - 3 - - ZeroDivisionError: division by zero - -The error traceback is now correctly formatted, showing the cell number in which the error happened:: - - In [1]: def foo(): - ...: return 3 / 0 - ...: - - Input In [2]: foo() - --------------------------------------------------------------------------- - ZeroDivisionError Traceback (most recent call last) - input In [2], in - ----> 1 foo() - - Input In [1], in foo() - 1 def foo(): - ----> 2 return 3 / 0 - - ZeroDivisionError: division by zero - -Miscellaneous -~~~~~~~~~~~~~ - - - ``~`` is now expanded when part of a path in most magics :ghpull:`13385` - - ``%/%%timeit`` magic now adds comma every thousands to make reading long number easier :ghpull:`13379` - - ``"info"`` messages can now be customised to hide some fields :ghpull:`13343` - - ``collections.UserList`` now pretty-prints :ghpull:`13320` - - The debugger now have a persistent history, which should make it less - annoying to retype commands :ghpull:`13246` - - ``!pip`` ``!conda`` ``!cd`` or ``!ls`` are likely doing the wrong thing, we - now warn users if they use it. :ghpull:`12954` - - make ``%precision`` work for ``numpy.float64`` type :ghpull:`12902` - - - - -Numfocus Small Developer Grant ------------------------------- - -To prepare for Python 3.10 we have also started working on removing reliance and -any dependency that is not Python 3.10 compatible; that include migrating our -test suite to pytest, and starting to remove nose. This also mean that the -``iptest`` command is now gone, and all testing is via pytest. - -This was in bog part thanks the NumFOCUS Small Developer grant, we were able to -allocate 4000 to hire `Nikita Kniazev (@Kojoley) `__ -who did a fantastic job at updating our code base, migrating to pytest, pushing -our coverage, and fixing a large number of bugs. I highly recommend contacting -them if you need help with C++ and Python projects - -You can find all relevant issues and PRs with the SDG 2021 tag ``__ - -Removing support for Older Python ---------------------------------- - - -We are also removing support for Python up to 3.7 allowing internal code to use more -efficient ``pathlib``, and make better use of type annotations. - -.. image:: ../_images/8.0/pathlib_pathlib_everywhere.jpg - :alt: "Meme image of Toy Story with Woody and Buzz, with the text 'pathlib, pathlib everywhere'" - - -We have about 34 PRs only to update some logic tu update some function from managing strings to -using Pathlib. - -The completer has also seen significant updates and make use of newer Jedi API -offering faster and more reliable tab completion. - .. DO NOT EDIT THIS LINE BEFORE RELEASE. FEATURE INSERTION POINT. -As a reminder, IPython master has diverged from the 7.x branch, thus master may -have more feature and API changes. - Backwards incompatible changes ------------------------------ diff --git a/docs/source/whatsnew/index.rst b/docs/source/whatsnew/index.rst index 775d18c..8eecbb9 100644 --- a/docs/source/whatsnew/index.rst +++ b/docs/source/whatsnew/index.rst @@ -33,6 +33,7 @@ development work they do here in a user friendly format. .. toctree:: :maxdepth: 1 + version8 version7 github-stats-7 version6 diff --git a/docs/source/whatsnew/version8.rst b/docs/source/whatsnew/version8.rst new file mode 100644 index 0000000..712c76c --- /dev/null +++ b/docs/source/whatsnew/version8.rst @@ -0,0 +1,428 @@ +============ + 8.x Series +============ + +IPython 8.0 +----------- + +IPython 8.0 is still in alpha/beta stage. Please help us improve those release notes +by sending PRs that modify docs/source/whatsnew/version8.rst + +IPython 8.0 is bringing a large number of new features and improvements to both the +user of the terminal and of the kernel via Jupyter. The removal of compatibility +with older version of Python is also the opportunity to do a couple of +performance improvement in particular with respect to startup time. +The 8.x branch started diverging from its predecessor around IPython 7.12 +(January 2020). + +This release contains 250+ Pull Requests, in addition to many of the features +and backports that have made it to the 7.x branch. All PRs that went into this +released are properly tagged with the 8.0 milestone if you wish to have a more +in depth look at the changes. + +Please fell free to send pull-requests to updates those notes after release, +I have likely forgotten a few things reviewing 250+ PRs. + +Dependencies changes/downstream packaging +----------------------------------------- + +Note that most of our building step have been changes to be (mostly) declarative +and follow PEP 517, we are trying to completely remove ``setup.py`` (:ghpull:`13238`) and are +looking for help to do so. + + - Minimum supported ``traitlets`` version if now 5+ + - we now require ``stack_data`` + - Minimal Python is now 3.8 + - ``nose`` is not a testing requirement anymore + - ``pytest`` replaces nose. + - ``iptest``/``iptest3`` cli entrypoints do not exists anymore. + - minimum officially support ``numpy`` version has been bumped, but this should + not have much effect on packaging. + + +Deprecation and removal +----------------------- + +We removed almost all features, arguments, functions, and modules that were +marked as deprecated between IPython 1.0 and 5.0. As reminder 5.0 was released +in 2016, and 1.0 in 2013. Last release of the 5 branch was 5.10.0, in may 2020. +The few remaining deprecated features we left have better deprecation warnings +or have been turned into explicit errors for better error messages. + +I will use this occasion to add the following requests to anyone emitting a +deprecation warning: + + - Please at at least ``stacklevel=2`` so that the warning is emitted into the + caller context, and not the callee one. + - Please add **since which version** something is deprecated. + +As a side note it is much easier to deal with conditional comparing to versions +numbers than ``try/except`` when a functionality change with version. + +I won't list all the removed features here, but modules like ``IPython.kernel``, +which was just a shim module around ``ipykernel`` for the past 8 years have been +remove, and so many other similar things that pre-date the name **Jupyter** +itself. + +We no longer need to add ``IPyhton.extensions`` to the PYTHONPATH because that is being +handled by ``load_extension``. + +We are also removing ``Cythonmagic``, ``sympyprinting`` and ``rmagic`` as they are now in +other packages and no longer need to be inside IPython. + + +Documentation +------------- + +Majority of our docstrings have now been reformatted and automatically fixed by +the experimental `Vélin `_ project, to conform +to numpydoc. + +Type annotations +---------------- + +While IPython itself is highly dynamic and can't be completely typed, many of +the function now have type annotation, and part of the codebase and now checked +by mypy. + + +Featured changes +---------------- + +Here is a features list of changes in IPython 8.0. This is of course non-exhaustive. +Please note as well that many features have been added in the 7.x branch as well +(and hence why you want to read the 7.x what's new notes), in particular +features contributed by QuantStack (with respect to debugger protocol, and Xeus +Python), as well as many debugger features that I was please to implement as +part of my work at QuanSight and Sponsored by DE Shaw. + +Better Tracebacks +~~~~~~~~~~~~~~~~~ + +The first on is the integration of the ``stack_data`` package; +which provide smarter informations in traceback; in particular it will highlight +the AST node where an error occurs which can help to quickly narrow down errors. + +For example in the following snippet:: + + def foo(i): + x = [[[0]]] + return x[0][i][0] + + + def bar(): + return foo(0) + foo( + 1 + ) + foo(2) + + +Calling ``bar()`` would raise an ``IndexError`` on the return line of ``foo``, +IPython 8.0 is capable of telling you, where the index error occurs:: + + + IndexError + Input In [2], in + ----> 1 bar() + ^^^^^ + + Input In [1], in bar() + 6 def bar(): + ----> 7 return foo(0) + foo( + ^^^^ + 8 1 + ^^^^^^^^ + 9 ) + foo(2) + ^^^^ + + Input In [1], in foo(i) + 1 def foo(i): + 2 x = [[[0]]] + ----> 3 return x[0][i][0] + ^^^^^^^ + +Corresponding location marked here with ``^`` will show up highlighted in +terminal and notebooks. + + +Autosuggestons +~~~~~~~~~~~~~~ + +Autosuggestion is a very useful feature available in `fish `__, `zsh `__, and `prompt-toolkit `__. + +`Ptpython `__ allows users to enable this feature in +`ptpython/config.py `__. + +This feature allows users to accept autosuggestions with ctrl e, ctrl f, +or right arrow as described below. + +1. Start ipython + +.. image:: ../_images/8.0/auto_suggest_1_prompt_no_text.png + +2. Run ``print("hello")`` + +.. image:: ../_images/8.0/auto_suggest_2_print_hello_suggest.png + +3. start typing ``print`` again to see the autosuggestion + +.. image:: ../_images/8.0/auto_suggest_3_print_hello_suggest.png + +4. Press ``ctrl-f``, or ``ctrl-e``, or ``right-arrow`` to accept the suggestion + +.. image:: ../_images/8.0/auto_suggest_4_print_hello.png + +You can also complete word by word: + +1. Run ``def say_hello(): print("hello")`` + +.. image:: ../_images/8.0/auto_suggest_second_prompt.png + +2. Start typing the first letter if ``def`` to see the autosuggestion + +.. image:: ../_images/8.0/auto_suggest_d_phantom.png + +3. Press ``alt-f`` (or ``escape`` followed by ``f``), to accept the first word of the suggestion + +.. image:: ../_images/8.0/auto_suggest_def_phantom.png + +Importantly, this feature does not interfere with tab completion: + +1. After running ``def say_hello(): print("hello")``, press d + +.. image:: ../_images/8.0/auto_suggest_d_phantom.png + +2. Press Tab to start tab completion + +.. image:: ../_images/8.0/auto_suggest_d_completions.png + +3A. Press Tab again to select the first option + +.. image:: ../_images/8.0/auto_suggest_def_completions.png + +3B. Press ``alt f`` (``escape``, ``f``) to accept to accept the first word of the suggestion + +.. image:: ../_images/8.0/auto_suggest_def_phantom.png + +3C. Press ``ctrl-f`` or ``ctrl-e`` to accept the entire suggestion + +.. image:: ../_images/8.0/auto_suggest_match_parens.png + + +Currently, autosuggestions are only shown in the emacs or vi insert editing modes: + +- The ctrl e, ctrl f, and alt f shortcuts work by default in emacs mode. +- To use these shortcuts in vi insert mode, you will have to create `custom keybindings in your config.py `__. + + +Show pinfo information in ipdb using "?" and "??" +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In IPDB, it is now possible to show the information about an object using "?" +and "??", in much the same way it can be done when using the IPython prompt:: + + ipdb> partial? + Init signature: partial(self, /, *args, **kwargs) + Docstring: + partial(func, *args, **keywords) - new function with partial application + of the given arguments and keywords. + File: ~/.pyenv/versions/3.8.6/lib/python3.8/functools.py + Type: type + Subclasses: + +Previously, ``pinfo`` or ``pinfo2`` command had to be used for this purpose. + + +Autoreload 3 feature +~~~~~~~~~~~~~~~~~~~~ + +Example: When an IPython session is ran with the 'autoreload' extension loaded, +you will now have the option '3' to select which means the following: + + 1. replicate all functionality from option 2 + 2. autoload all new funcs/classes/enums/globals from the module when they are added + 3. autoload all newly imported funcs/classes/enums/globals from external modules + +Try ``%autoreload 3`` in an IPython session after running ``%load_ext autoreload`` + +For more information please see the following unit test : ``extensions/tests/test_autoreload.py:test_autoload_newly_added_objects`` + + + + +History Range Glob feature +~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Previously, when using ``%history``, users could specify either +a range of sessions and lines, for example: + +.. code-block:: python + + ~8/1-~6/5 # see history from the first line of 8 sessions ago, + # to the fifth line of 6 sessions ago.`` + +Or users could specify a glob pattern: + +.. code-block:: python + + -g # glob ALL history for the specified pattern. + +However users could *not* specify both. + +If a user *did* specify both a range and a glob pattern, +then the glob pattern would be used (globbing *all* history) *and the range would be ignored*. + +With this enhancement, if a user specifies both a range and a glob pattern, then the glob pattern will be applied to the specified range of history. + +Don't start a multi line cell with sunken parenthesis +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +From now on IPython will not ask for the next line of input when given a single +line with more closing than opening brackets. For example, this means that if +you (mis)type ``]]`` instead of ``[]``, a ``SyntaxError`` will show up, instead of +the ``...:`` prompt continuation. + +IPython shell for ipdb interact +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The ipdb ``interact`` starts an IPython shell instead of Python's built-in ``code.interact()``. + +Automatic Vi prompt stripping +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +When pasting code into IPython, it will strip the leading prompt characters if +there are any. For example, you can paste the following code into the console - +it will still work, even though each line is prefixed with prompts (`In`, +`Out`):: + + In [1]: 2 * 2 == 4 + Out[1]: True + + In [2]: print("This still works as pasted") + + +Previously, this was not the case for the Vi-mode prompts:: + + In [1]: [ins] In [13]: 2 * 2 == 4 + ...: Out[13]: True + ...: + File "", line 1 + [ins] In [13]: 2 * 2 == 4 + ^ + SyntaxError: invalid syntax + +This is now fixed, and Vi prompt prefixes - ``[ins]`` and ``[nav]`` - are +skipped just as the normal ``In`` would be. + +IPython shell can be started in the Vi mode using ``ipython --TerminalInteractiveShell.editing_mode=vi``, +You should be able to change mode dynamically with ``%config TerminalInteractiveShell.editing_mode='vi'`` + +Empty History Ranges +~~~~~~~~~~~~~~~~~~~~ + +A number of magics that take history ranges can now be used with an empty +range. These magics are: + + * ``%save`` + * ``%load`` + * ``%pastebin`` + * ``%pycat`` + +Using them this way will make them take the history of the current session up +to the point of the magic call (such that the magic itself will not be +included). + +Therefore it is now possible to save the whole history to a file using simple +``%save ``, load and edit it using ``%load`` (makes for a nice usage +when followed with :kbd:`F2`), send it to dpaste.org using ``%pastebin``, or +view the whole thing syntax-highlighted with a single ``%pycat``. + +Traceback improvements +~~~~~~~~~~~~~~~~~~~~~~ + + +Previously, error tracebacks for errors happening in code cells were showing a hash, the one used for compiling the Python AST:: + + In [1]: def foo(): + ...: return 3 / 0 + ...: + + In [2]: foo() + --------------------------------------------------------------------------- + ZeroDivisionError Traceback (most recent call last) + in + ----> 1 foo() + + in foo() + 1 def foo(): + ----> 2 return 3 / 0 + 3 + + ZeroDivisionError: division by zero + +The error traceback is now correctly formatted, showing the cell number in which the error happened:: + + In [1]: def foo(): + ...: return 3 / 0 + ...: + + Input In [2]: foo() + --------------------------------------------------------------------------- + ZeroDivisionError Traceback (most recent call last) + input In [2], in + ----> 1 foo() + + Input In [1], in foo() + 1 def foo(): + ----> 2 return 3 / 0 + + ZeroDivisionError: division by zero + +Miscellaneous +~~~~~~~~~~~~~ + + - ``~`` is now expanded when part of a path in most magics :ghpull:`13385` + - ``%/%%timeit`` magic now adds comma every thousands to make reading long number easier :ghpull:`13379` + - ``"info"`` messages can now be customised to hide some fields :ghpull:`13343` + - ``collections.UserList`` now pretty-prints :ghpull:`13320` + - The debugger now have a persistent history, which should make it less + annoying to retype commands :ghpull:`13246` + - ``!pip`` ``!conda`` ``!cd`` or ``!ls`` are likely doing the wrong thing, we + now warn users if they use it. :ghpull:`12954` + - make ``%precision`` work for ``numpy.float64`` type :ghpull:`12902` + + + + +Numfocus Small Developer Grant +------------------------------ + +To prepare for Python 3.10 we have also started working on removing reliance and +any dependency that is not Python 3.10 compatible; that include migrating our +test suite to pytest, and starting to remove nose. This also mean that the +``iptest`` command is now gone, and all testing is via pytest. + +This was in bog part thanks the NumFOCUS Small Developer grant, we were able to +allocate 4000 to hire `Nikita Kniazev (@Kojoley) `__ +who did a fantastic job at updating our code base, migrating to pytest, pushing +our coverage, and fixing a large number of bugs. I highly recommend contacting +them if you need help with C++ and Python projects + +You can find all relevant issues and PRs with the SDG 2021 tag ``__ + +Removing support for Older Python +--------------------------------- + + +We are also removing support for Python up to 3.7 allowing internal code to use more +efficient ``pathlib``, and make better use of type annotations. + +.. image:: ../_images/8.0/pathlib_pathlib_everywhere.jpg + :alt: "Meme image of Toy Story with Woody and Buzz, with the text 'pathlib, pathlib everywhere'" + + +We have about 34 PRs only to update some logic tu update some function from managing strings to +using Pathlib. + +The completer has also seen significant updates and make use of newer Jedi API +offering faster and more reliable tab completion. +