CHANGELOG

CHANGELOG
=========

New features:

- `NestedCompleter` now accepts an optional separator argument which allows to specify custom
  separators. Space will still be the default separator.
- `NestedCompleter.from_nested_dict` now accepts optional `ignore_case` and `separator` arguments
  of the default constructor and passes them on recursively to all contained nested separator
  instances.

3.0.41: 2023-11-14
------------------

Fixes:
- Fix regression regarding IPython input hook (%gui) integration.

3.0.40: 2023-11-10
------------------

Fixes:
- Improved Python 3.12 support (fixes event loop `DeprecationWarning`).

New features:
- Vi key bindings: `control-t` and `control-d` for indent/unindent in insert
  mode.
- Insert partial suggestion when `control+right` is pressed, similar to Fish.
- Use sphinx-nefertiti theme for the docs.


3.0.39: 2023-07-04
------------------

Fixes:
- Fix `RuntimeError` when `__breakpointhook__` is called from another thread.
- Fix memory leak in filters usage.
- Ensure that key bindings are handled in the right context (when using
  contextvars).

New features:
- Accept `in_thread` keyword in `prompt_toolkit.shortcuts.prompt()`.
- Support the `NO_COLOR` environment variable.


3.0.38: 2023-02-28
------------------

Fixes:
- Fix regression in filters. (Use of `WeakValueDictionary` caused filters to
  not be cached).

New features:
- Use 24-bit true color now by default on Windows 10/11.


3.0.37: 2023-02-21
------------------

Bug fixes:
- Fix `currentThread()` deprecation warning.
- Fix memory leak in filters.
- Make VERSION tuple numeric.

New features:
- Add `.run()` method in `TelnetServer`. (To be used instead of
  `.start()/.stop()`.

Breaking changes:
- Subclasses of `Filter` have to call `super()` in their `__init__`.
- Drop support for Python 3.6:
  * This includes code cleanup for Python 3.6 compatibility.
  * Use `get_running_loop()` instead of `get_event_loop()`.
  * Use `asyncio.run()` instead of `asyncio.run_until_complete()`.


3.0.36: 2022-12-06
------------------

Fixes:
- Another Python 3.6 fix for a bug that was introduced in 3.0.34.


3.0.35: 2022-12-06
------------------

Fixes:
- Fix bug introduced in 3.0.34 for Python 3.6. Use asynccontextmanager
  implementation from prompt_toolkit itself.


3.0.34: 2022-12-06
------------------

Fixes:
- Improve completion performance in various places.
- Improve renderer performance.
- Handle `KeyboardInterrupt` when the stacktrace of an unhandled error is
  displayed.
- Use correct event loop in `Application.create_background_task()`.
- Fix `show_cursor` attribute in `ScrollablePane`.


3.0.33: 2022-11-21
------------------

Fixes:
- Improve termination of `Application`. Don't suppress `CancelledError`. This
  fixes a race condition when an `Application` gets cancelled while we're
  waiting for the background tasks to complete.
- Fixed typehint for `OneStyleAndTextTuple`.
- Small bugfix in `CombinedRegistry`. Fixed missing `@property`.


3.0.32: 2022-11-03
------------------

Bug fixes:
- Use `DummyInput` by default in `create_input()` if `sys.stdin` does not have
  a valid file descriptor. This fixes errors when `sys.stdin` is patched in
  certain situations.
- Fix control-c key binding for `ProgressBar` when the progress bar was not
  created from the main thread. The current code would try to kill the main
  thread when control-c was pressed.

New features:
- Accept a `cancel_callback` in `ProgressBar` to specify the cancellation
  behavior for when `control-c` is pressed.
- Small performance improvement in the renderer.


3.0.31: 2022-09-02
------------------

New features:
- Pass through `name` property in `TextArea` widget to `Buffer`.
- Added a `enable_cpr` parameter to `Vt100_Output`, `TelnetServer` and
  `PromptToolkitSSHServer`, to completely disable CPR support instead of
  automatically detecting it.


3.0.30: 2022-06-27
------------------

New features:
- Allow zero-width-escape sequences in `print_formatted_text`.
- Add default value option for input dialog.
- Added `has_suggestion` filter.

Fixes:
- Fix rendering of control-shift-6 (or control-^). Render as '^^'
- Always wrap lines in the Label widget by default.
- Fix enter key binding in system toolbar in Vi mode.
- Improved handling of stdout objects that don't have a 'buffer' attribute. For
  instance, when using `renderer_print_formatted_text` in a Jupyter Notebook.


3.0.29: 2022-04-04
------------------

New features:
- Accept 'handle_sigint' parameter in PromptSession.

Fixes
- Fix 'variable referenced before assignment' error in vt100 mouse bindings.
- Pass `handle_sigint` from `Application.run` to `Application.run_async`.
- Fix detection of telnet client side changes.
- Fix `print_container` utility (handle `EOFError`).

Breaking changes:
- The following are now context managers:
  `create_pipe_input`, `PosixPipeInput` and `Win32PipeInput`.


3.0.28: 2022-02-11
------------------

New features:
- Support format specifiers for HTML and ANSI formatted text.
- Accept defaults for checkbox and radio list, and their corresponding dialogs.

Fixes:
- Fix resetting of cursor shape after the application terminates.


3.0.27: 2022-02-07
------------------

New features:
- Support for cursor shapes. The cursor shape for prompts/applications can now
  be configured, either as a fixed cursor shape, or in case of Vi input mode,
  according to the current input mode.
- Handle "cursor forward" command in ANSI formatted text. This makes it
  possible to render many kinds of generated ANSI art.
- Accept `align` attribute in `Label` widget.
- Added `PlainTextOutput`: an output implementation that doesn't render any
  ANSI escape sequences. This will be used by default when redirecting stdout
  to a file.
- Added `create_app_session_from_tty`: a context manager that enforces
  input/output to go to the current TTY, even if stdin/stdout are attached to
  pipes.
- Added `to_plain_text` utility for converting formatted text into plain text.

Fixes:
- Don't automatically use `sys.stderr` for output when `sys.stdout` is not a
  TTY, but `sys.stderr` is. The previous behavior was confusing, especially
  when rendering formatted text to the output, and we expect it to follow
  redirection.

3.0.26: 2022-01-27
------------------

Fixes:
- Fixes issue introduced in 3.0.25: Don't handle SIGINT on Windows.


3.0.25: 2022-01-27
------------------

Fixes:
- Use `DummyOutput` when `sys.stdout` is `None` and `DummyInput` when
  `sys.stdin` is `None`. This fixes an issue when the code runs on windows,
  using pythonw.exe and still tries to interact with the terminal.
- Correctly reset `Application._is_running` flag in case of exceptions in some
  situations.
- Handle SIGINT (when sent from another process) and allow binding it to a key
  binding. For prompt sessions, the behavior is now identical to pressing
  control-c.
- Increase the event loop `slow_duration_callback` by default to 0.5. This
  prevents printing warnings if rendering takes too long on slow systems.


3.0.24: 2021-12-09
------------------

Fixes:
- Prevent window content overflowing when using scrollbars.
- Handle `PermissionError` when trying to attach /dev/null in vt100 input.


3.0.23: 2021-11-26
------------------

Fixes:
- Fix multiline bracketed paste on Windows

New features:
- Add support for some CSI 27 modified variants of "Enter" for xterm in the
  vt100 input parser.


3.0.22: 2021-11-04
------------------

Fixes:
- Fix stopping of telnet server (capture cancellation exception).


3.0.21: 2021-10-21
------------------

New features:
- Improved mouse support:
  * Support for click-drag, which is useful for selecting text.
  * Detect mouse movements when no button is pressed.
- Support for Python 3.10.


3.0.20: 2021-08-20
------------------

New features:
- Add support for strikethrough text attributes.
- Set up custom breakpointhook while an application is running (if no other
  breakpointhook was installed). This enhances the usage of PDB for debugging
  applications.
- Strict type checking is now enabled.

Fixes:
- Ensure that `print_formatted_text` is always printed above the running
  application, like `patch_stdout`. (Before, `patch_stdout` was even completely
  ignored in case of `print_formatted_text, so there was no proper way to use
  it in a running application.)
- Fix handling of non-bmp unicode input on Windows.
- Set minimum Python version to 3.6.2 (Some 3.6.2 features were used).


3.0.19: 2021-06-17
------------------

Fixes:
- Make the flush method of the vt100 output implementation re-entrant (fixes an
  issue when using aiogevent).
- Fix off-by-one in `FormattedTextControl` mouse logic.
- Run `print_container` always in a thread (avoid interfering with possible
  event loop).
- Make sphinx autodoc generation platform agnostic (don't import Windows stuff
  when generating Sphinx docs).


3.0.18: 2021-03-22
------------------

New features:
- Added `in_thread` parameter to `Application.run`.
  This is useful for running an application in a background thread, while the
  main thread blocks. This way, we are sure not to interfere with an event loop
  in the current thread. (This simplifies some code in ptpython and fixes an
  issue regarding leaking file descriptors due to not closing the event loop
  that was created in this background thread.)


3.0.17: 2021-03-11
------------------

New features:
- Accept `style` parameter in `print_container` utility.
- On Windows, handle Control-Delete.

Fixes:
- Avoid leaking file descriptors in SSH server.


3.0.16: 2021-02-11
------------------

New features:
- Added `ScrollablePane`: a scrollable layout container.
  This allows applications to build a layout, larger than the terminal, with a
  vertical scroll bar. The vertical scrolling will be done automatically when
  certain widgets receive the focus.
- Added `DeduplicateCompleter and `ConditionalCompleter`.
- Added `deduplicate` argument to `merge_completers`.


3.0.15: 2021-02-10
------------------

Fixes:
- Set stdout blocking when writing in vt100 output. Fixes an issue when uvloop
  is used and big amounts of text are written.
- Guarantee height of at least 1 for both labels and text areas.
- In the `Window` rendering, take `dont_extend_width`/`dont_extend_height` into
  account. This fixes issues where one window is enlarged unexpectedly because
  it's bundled with another window in a `HSplit`/`VSplit`, but with different
  width/height.
- Don't handle `SIGWINCH` in progress bar anymore. (The UI runs in another
  thread, and we have terminal size polling now).
- Fix several thread safety issues and a race condition in the progress bar.
- Fix thread safety issues in `Application.invalidate()`. (Fixes a
  `RuntimeError` in some situations when using progress bars.)
- Fix handling of mouse events on Windows if we have a Windows 10 console with
  ANSI support.
- Disable `QUICK_EDIT_MODE` on Windows 10 when mouse support is requested.


3.0.14: 2021-01-24
------------------

New features:
- Disable bell when `PROMPT_TOOLKIT_BELL=false` environment variable has been
  set.

Fixes:
- Improve cancellation of history loading.


3.0.13: 2021-01-21
------------------

Fixes:
- Again, fixed the race condition in `ThreadedHistory`. Previous fix was not
  correct.


3.0.12: 2021-01-21
------------------

Fixes:
- Fixed a race condition in `ThreadedHistory` that happens when continuously
  pasting input text (which would continuously repopulate the history).
- Move cursor key mode resetting (for vt100 terminals) to the renderer. (Mostly
  cleanup).


3.0.11: 2021-01-20
------------------

New features:
- Poll terminal size: better handle resize events when the application runs in
  a thread other than the main thread (where handling SIGWINCH doesn't work) or
  in the Windows console.

Fixes:
- Fix bug in system toolbar. The execution of system commands was broken.
- A refactoring of patch_stdout that includes several fixes.
  * We know look at the `AppSession` in order to see which application is
    running, rather then looking at the event loop which is installed when
    `StdoutProxy` is created. This way, `patch_stdout` will work when
    prompt_toolkit applications with a different event loop run.
  * Fix printing when no application/event loop is running.
  * Fixed the `raw` argument of `PatchStdout`.
- A refactoring of the `ThreadedHistory`, which includes several fixes, in
  particular a race condition (see issue #1158) that happened when editing
  input while a big history was still being loaded in the background.


3.0.10: 2021-01-08
------------------

New features:
- Improved `WordCompleter`: accept `display_dict`. Also accept formatted text
  for both `display_dict` and `meta_dict`.
- Allow customization of button arrows.

Fixes:
- Correctly recognize backtab on Windows.
- Show original display text in fuzzy completer if no filtering was done.


3.0.9: 2021-01-05
-----------------

New features:
- Handle c-tab for TERM=linux.

Fixes:
- Improve rendering speed of `print_formatted_text`. (Don't render styling
  attributes to output between fragments that have identical styling.)
- Gracefully handle `FileHistory` decoding errors.
- Prevent asyncio deprecation warnings.


3.0.8: 2020-10-12
-----------------

New features:
- Added `validator` parameter to `input_dialog`.

Fixes:
- Cope with stdout not having a working `fileno`.
- Handle situation when /dev/null is piped into stdin, or when stdin is closed
  somehow.
- Fix for telnet/ssh server: `isatty` method was not implemented.
- Display correct error when a tuple is passed into `to_formatted_text`.
- Pass along WORD parameter in `Document._is_word_before_cursor_complete`.
  Fixes some key bindings.
- Expose `ProgressBarCounter` in shortcuts module.


3.0.7: 2020-08-29
-----------------

New features:
- New "placeholder" parameter added to `PromptSession`.

Other changes:
- The "respond to CPR" logic has been moved from the `Input` to `Output`
  classes (this does clean up some code).

Fixes:
- Bugfix in shift-selection key bindings.
- Fix height calculation of `FormattedTextControl` when line wrapping is turned
  on.
- Fixes for SSH server:
  * Missing encoding property.
  * Fix failure in "set_line_mode" call.
  * Handle `BrokenPipeError`.


3.0.6: 2020-08-10
-----------------

New features:
- The SSH/Telnet adaptors have been refactored and improved in several ways.
  See issues #876 and PR #1150 and #1184 on GitHub.
  * Handle terminal types for both telnet and SSH sessions.
  * Added pipe input abstraction. (base class for `PosixPipeInput` and
    `Win32PipeInput`).
  * The color depth logic has been refactored and moved to the `Output`
    implementations. Added `get_default_color_depth` method to `Output`
    objects.
  * All line feet are now preceded by a carriage return in the telnet
    connection stdout.
- Introduce `REPLACE_SINGLE` input mode for Vi key bindings.
- Improvements to the checkbox implementation:
    * Hide the scrollbar for a single checkbox.
    * Added a "checked" setter to the checkbox.
- Expose `KeyPressEvent` in key_binding/__init__.py (often used in type
  annotations).
- The renderer has been optimized so that no trailing spaces are generated
  (this improves copying in some terminals).

Fixes:
- Ignore F21..F24 key bindings by default.
- Fix auto_suggest key bindings when suggestion text is empty.
- Bugfix in SIGWINCH handling.
- Handle bug in HSplit/VSplit when the number of children is zero.
- Bugfix in CPR handling in renderer. Proper cancellation of pending tasks.
- Ensure rprompt aligns with input.
- Use `sys.stdin.encoding` for decoding stdin stream.


3.0.5: 2020-03-26
-----------------

Fixes:
- Bugfix in mouse handling on Windows.


3.0.4: 2020-03-06
-----------------

New features:
- Added many more vt100 ANSI sequences and keys.
- Improved control/shift key support in Windows.
- No Mypy errors in prompt_toolkit anymore.
- Added `set_exception_handler` optional argument to `PromptSession.prompt()`.

Fixes:
- Bugfix in invalidate code. `PromptSession` was invalidating the UI
  continuously.
- Add uvloop support (was broken due to an issue in our `call_soon_threadsafe`).
- Forwarded `set_exception_handler` in `Application.run` to the `run_async` call.
- Bugfix in `NestedCompleter` when there is a leading space.

Breaking changes:
- `ShiftControl` has been replaced with `ControlShift` and `s-c` with `c-s` in
  key bindings. Aliases for backwards-compatibility have been added.


3.0.3: 2020-01-26
-----------------

New features:
- Improved support for "dumb" terminals.
- Added support for new keys (vt100 ANSI sequences): Alt +
  home/end/page-up/page-down/insert.
- Better performance for the "regular languages compiler". Generate fewer and
  better regular expressions. This should improve the start-up time for
  applications using this feature.
- Better detection of default color depth.
- Improved the progress bar:
  * Set "time left" to 0 when done or stopped.
  * Added `ProgressBarCounter.stopped`.
- Accept callables for `scroll_offset`, `min_brightness` and `max_brightness`.
- Added `always_prefer_tty` parameters to `create_input()` and `create_output()`.
- Create a new event loop in `Application.run()` if `get_event_loop()` raises
  `Runtimeerror`.

Fixes:
- Correct cancellation of flush timers for input. (Fixes resource leak where
  too many useless coroutines were created.)
- Improved the Win32 input event loop. This fixes a bug where the
  prompt_toolkit application is stopped by something other than user input. (In
  that case, the application would hang, waiting for input.) This also fixes a
  `RuntimeError` in the progress bar code.
- Fixed `line-number.current` style. (was `current-line-number`.)
- Handle situation where stdout is no longer a tty (fix bug in `get_size`).
- Fix parsing of true color in ANSI strings.
- Ignore `invalidate()` if the application is not running.


3.0.2: 2019-11-30
-----------------

Fixes:
- Bugfix in the UI invalidation. Fixes an issue when the application runs again
  on another event loop.
  See: https://github.com/ipython/ipython/pull/11973


3.0.1: 2019-11-28
-----------------

New features:
- Added `new_eventloop_with_inputhook` function.
- Set exception handler from within `Application.run_async`.
- Applied Black code style.

Fixes:
- No longer expect a working event loop in the `History` classes.
  (Fix for special situations when a `ThreadedHistory` is created before the
  event loop has been set up.)
- Accept an empty prompt continuation.
- A few fixes to the `Buffer` tempfile code.


3.0.0: 2019-11-24
-----------------

New features:
- (almost) 100% type annotated.
- Native asyncio instead of custom event loops.
- Added shift-based text selection (use shift+arrows to start selecting text).

Breaking changes:
- Python 2 support has been dropped. Minimal Python version is now 3.6,
  although 3.7 is preferred (because of ContextVars).
- Native asyncio, so some async code becomes slightly different.
- The active `Application` became a contextvar. Which means that it should be
  propagated correctly to the code that requires it. However, random other
  threads or coroutines won't be able to know what the current application is.
- The dialog shortcuts API changed. All dialog functions now return an
  `Application`. You still have to call either `run()` or `run_async` on the
  `Application` object.
- The way inputhooks work is changed.
- `patch_stdout` now requires an `Application` as input.


2.0.9: 2019-02-19
-----------------

Bug fixes:
- Fixed `Application.run_system_command` on Windows.
- Fixed bug in ANSI text formatting: correctly handle 256/true color sequences.
- Fixed bug in WordCompleter. Provide completions when there's a space before
  the cursor.


2.0.8: 2019-01-27
-----------------

Bug fixes:
- Fixes the issue where changes made to the buffer in the accept handler were
  not reflected in the history.
- Fix in the application invalidate handler. This prevents a significant slow
  down in some applications after some time (especially if there is a refresh
  interval).
- Make `print_container` utility work if the input is not a pty.

New features:
- Underline non breaking spaces instead of rendering as '&'.
- Added mouse support for radio list.
- Support completion styles for `READLINE_LIKE` display method.
- Accept formatted text in the display text of completions.
- Added a `FuzzyCompleter` and `FuzzyWordCompleter`.
- Improved error handling in Application (avoid displaying a meaningless
  AssertionError in many cases).


2.0.7: 2018-10-30
-----------------

Bug fixes:
- Fixed assertion in PromptSession: the style_transformation check was wrong.
- Removed 'default' attribute in PromptSession. Only ask for it in the
  `prompt()` method. This fixes the issue that passing `default` once, will
  store it for all consequent calls in the `PromptSession`.
- Ensure that `__pt_formatted_text__` always returns a `FormattedText`
  instance. This fixes an issue with `print_formatted_text`.

New features:
- Improved handling of situations where stdin or stdout are not a terminal.
  (Print warning instead of failing with an assertion.)
- Added `print_container` utility.
- Sound bell when attempting to edit read-only buffer.
- Handle page-down and page-up keys in RadioList.
- Accept any `collections.abc.Sequence` for HSplit/VSplit children (instead of
  lists only).
- Improved Vi key bindings: return to navigation mode when Insert is pressed.


2.0.6: 2018-10-12
-----------------

Bug fixes:
- Don't use the predefined ANSI colors for colors that are defined as RGB.
  (Terminals can assign different color schemes for ansi colors, and we don't
  want use any of those for colors that are defined like #aabbcc for instance.)
- Fix in handling of CPRs when patch_stdout is used.

Backwards incompatible changes:
- Change to the `Buffer` class. Reset the buffer unless the `accept_handler`
  returns `True` (which means: "keep_text"). This doesn't affect applications
  that use `PromptSession`.

New features:
- Added `AdjustBrightnessStyleTransformation`. This is a simple style
  transformation that improves the rendering on terminals with light or dark
  background.
- Improved performance (string width caching and line height calculation).
- Improved `TextArea`:
  * Exposed `focus_on_click`.
  * Added attributes: `auto_suggest`, `complete_while_typing`, `history`,
    `get_line_prefix`, `input_processors`.
  * Made attributes writable: `lexer`, `completer`, `complete_while_typing`,
    `accept_handler`, `read_only`, `wrap_lines`.

2.0.5: 2018-09-30
-----------------

Bug fixes:
- Fix in `DynamicContainer`. Return correct result for `get_children`. This
  fixes a bug related to focusing.
- Properly compute length of `start`, `end` and `sym_b` characters of
  progress bar.
- CPR (cursor position request) fix.

Backwards incompatible changes:
- Stop restoring `PromptSession` attributes when exiting prompt.

New features:
- Added `get_line_prefix` attribute to window. This opens many
  possibilities:
  * Line wrapping (soft and hard) can insert whitespace in front
    of the line, or insert some symbols in front. Like the Vim "breakindent"
    option.
  * Single line prompts also support line continuations now.
  * Line continuations can have a variable width.
- For VI mode: implemented temporary normal mode (control-O in insert mode).
- Added style transformations API. Useful for swapping between light and
  dark color schemes. Added `swap_light_and_dark_colors` parameter to
  `prompt()` function.
- Added `format()` method to ANSI formatted text.
- Set cursor position for Button widgets.
- Added `pre_run` argument to `PromptSession.prompt()` method.


2.0.4: 2018-07-22
-----------------

Bug fixes:
- Fix render height for rendering full screen applications in Windows.
- Fix in `TextArea`. Set `accept_handler` to `None` if not given.
- Go to the beginning of the next line when enter is pressed in Vi navigation
  mode, and the buffer doesn't have an accept handler.
- Fix the `default` argument of the `prompt` function when called multiple
  times.
- Display decomposed multiwidth characters correctly.
- Accept `history` in `prompt()` function again.

Backwards incompatible changes:
- Renamed `PipeInput` to `PosixPipeInput`. Added `Win32PipeInput` and
  `create_input_pipe`.
- Pass `buffer` argument to the `accept_handler` of `TextArea`.

New features:
- Added `accept_default` argument to `prompt()`.
- Make it easier to change the body/title of a Frame/Dialog.
- Added `DynamicContainer`.
- Added `merge_completers` for merging multiple completers together.
- Add vt100 data to key presses in Windows.
- Handle left/right key bindings in Vi block insert mode.


2.0.3: 2018-06-08
-----------------

Bug fixes:
- Fix in 'x' and 'X' Vi key bindings. Correctly handle line endings and args.
- Fixed off by one error in Vi line selection.
- Fixed bugs in Vi block selection. Correctly handle lines that the selection
  doesn't cross.
- Python 2 bugfix. Handle str/unicode correctly.
- Handle option+left/right in iTerm.


2.0.2: 2018-06-03
-----------------

Bug fixes:
- Python 3.7 support: correctly handle StopIteration in asynchronous generator.
- Fixed off-by-one bug in Vi visual block mode.
- Bugfix in TabsProcessor: handle situations when the cursor is at the end of
  the line.


2.0.1: 2018-06-02
-----------------

Version 2.0 includes a big refactoring of the internal architecture. This
includes the merge of the CommandLineInterface and the Application object, a
rewrite of how user controls are focused, a rewrite of how event loops work
and the removal of the buffers dictionary. This introduces many backwards
incompatible changes, but the result is a very nice and powerful architecture.

Most architectural changes effect full screen applications. For applications
that use `prompt_toolkit.shortcuts` for simple prompts, there are fewer
incompatibilities.

Changes:

- No automatic translation from \r into \n during the input processing. These
  are two different keys that can be handled independently. This is a big
  backward-incompatibility, because the `Enter` key is `ControlM`, not
  `ControlJ`. So, now that we stopped translating \r into \n, it could be that
  custom key bindings for `Enter` don't work anymore. Make sure to bind
  `Keys.Enter` instead of `Keys.ControlJ` for handling the `Enter` key.

- The `CommandLineInterface` and the `Application` classes are merged. First,
  `CommandLineInterface` contained all the I/O objects (like the input, output
  and event loop), while the `Application` contained everything else. There was
  no practical reason to keep this separation. (`CommandLineInterface` was
  mostly a proxy to `Application`.)

  A consequence is that almost all code which used to receive a
  `CommandLineInterface`, will now use an `Application`. Usually, where we
  had an attribute `cli`, we'll now have an attribute `app`.

  Secondly, the `Application` object is no longer passed around. The `get_app`
  function can be used at any time to acquire the active application.

  (For backwards-compatibility, we have aliases to the old names, whenever
  possible.)

- prompt_toolkit no longer depends on Pygments, but it can still use Pygments
  for its color schemes and lexers. In many places we used Pygments "Tokens",
  this has been replaced by the concept of class names, somewhat similar to
  HTML and CSS.

  * `PygmentsStyle` and `PygmentsLexer` adaptors are available for
     plugging in Pygments styles and lexers.

  * Wherever we had a list of `(Token, text)` tuples, we now have lists of
    `(style_string, text)` tuples. The style string can contain both inline
    styling as well as refer to a class from the style sheet. `PygmentsTokens`
    is an adaptor that converts a list of Pygments tokens into a list of
    `(style_string, text)` tuples.

- Changes in the `Style` classes.

  * `style.from_dict` does not exist anymore. Instantiate the ``Style`` class
    directory to create a new style. ``Style.from_dict`` can be used to create
    a style from a dictionary, where the dictionary keys are a space separated
    list of class names, and the values, style strings (like before).

  * `print_tokens` was renamed to `print_formatted_text`.

  * In many places in the layout, we accept a parameter named `style`. All the
    styles from the layout hierarchy are combined to decide what style to be
    used.

  * The ANSI color names were confusing and inconsistent with common naming
    conventions. This has been fixed, but aliases for the original names were
    kept.

- The way focusing works is different. Before it was always a `Buffer` that
  was focused, and because of that, any visible `BufferControl` that contained
  this `Buffer` would be focused. Now, any user control can be focused. All
  of this is handled in the `Application.layout` object.

- The `buffers` dictionary (`CommandLineInterface.buffers`) does not exist
  anymore. Further, `buffers` was a `BufferMapping` that keeps track of which
  buffer has the focus. This significantly reduces the freedom for creating
  complex applications. We wanted to move toward a layout that can be defined
  as a (hierarchical) collection of user widgets. A user widget does not need
  to have a `Buffer` underneath and any widget should be focusable.

  * `layout.Layout` was introduced to contain the root layout widget and keep
    track of the focus.

- The key bindings were refactored. It became much more flexible to combine
  sets of key bindings.

  * `Registry` has been renamed to `KeyBindings`.
  * The `add_binding` function has been renamed to simply `add`.
  * Every `load_*` function returns one `KeyBindings` objects, instead of
    populating an existing one, like before.
  * `ConditionalKeyBindings` was added. This can be used to enable/disable
    all the key bindings from a given `Registry`.
  * A function named `merge_key_bindings` was added. This takes a list of
    `KeyBindings` and merges them into one.
  * `key_binding.defaults.load_key_bindings` was added to load all the key
    bindings.
  * `KeyBindingManager` has been removed completely.
  * `input_processor` was renamed to `key_processor`.

  Further:

  * The `Key` class does not exist anymore. Every key is a string and it's
    considered fine to use string literals in the key bindings. This is more
    readable, but we still have run-time validation. The `Keys` enum still
    exist (for backwards-compatibility, but also to have an overview of which
    keys are supported.)
  * 'enter' and 'tab' are key aliases for 'c-m' and 'c-i'.

- User controls can define key bindings, which are active when the user control
  is focused.

  * `UIControl` got a `get_key_bindings` (abstract) method.

- Changes in the layout engine:

  * `LayoutDimension` was renamed to `Dimension`.
  * `VSplit` and `HSplit` now take a `padding` argument.
  * `VSplit` and `HSplit` now take an `align` argument.
    (TOP/CENTER/BOTTOM/JUSTIFY) or (LEFT/CENTER/RIGHT/JUSTIFY).
  * `Float` now takes `allow_cover_cursor` and `attach_to_window` arguments.
  * `Window` got an `WindowAlign` argument. This can be used for the alignment
    of the content. `TokenListControl` (renamed to `FormattedTextControl`) does
    not have an alignment argument anymore.
  * All container objects, like `Window`, got a `style` argument. The style for
    parent containers propagate to child containers, but can be overridden.
    This is in particular useful for setting a background color.
  * `FillControl` does not exist anymore. Use the `style` and `char` arguments
    of the `Window` class instead.
  * `DummyControl` was added.
  * The continuation function of `PromptMargin` now takes `line_number` and
    `is_soft_wrap` as input.

- Changes to `BufferControl`:

  * The `InputProcessor` class has been refactored. The `apply_transformation`
    method should now takes a `TransformationInput` object as input.

  * The text `(reverse-i-search)` is now displayed through a processor. (See
    the `shortcuts` module for an example of its usage.)

- `widgets` and `dialogs` modules:

  * A small collection of widgets was added. These are more complex collections
    of user controls that are ready to embed in a layout. A `shortcuts.dialogs`
    module was added as a high level API for displaying input, confirmation and
    message dialogs.

  * Every class that exposes a ``__pt_container__`` method (which is supposed
    to return a ``Container`` instance) is considered a widget. The
    ``to_container`` shortcut will call this method in situations where a
    ``Container`` object is expected. This avoids inheritance from other
    ``Container`` types, but also having to unpack the container object from
    the widget, in case we would have used composition.

  * Warning: The API of the widgets module is not considered stable yet, and
    can change is the future, if needed.

- Changes to `Buffer`:

  * A `Buffer` no longer takes an `accept_action`.  Both `AcceptAction` and
    `AbortAction` have been removed. Instead it takes an `accept_handler`.

- Changes regarding auto completion:

  * The left and right arrows now work in the multi-column auto completion
    menu.
  * By default, autocompletion is synchronous. The completer needs to be
    wrapped in `ThreadedCompleter` in order to get asynchronous autocompletion.
  * When the completer runs in a background thread, completions will be
    displayed as soon as they are generated. This means that we don't have to
    wait for all the completions to be generated, before displaying the first
    one. The completion menus are updated as soon as new completions arrive.

- Changes regarding input validation:

  * Added the `Validator.from_callable` class method for easy creation of
    new validators.

- Changes regarding the `History` classes:

  * The `History` base class has a different interface. This was needed for
    asynchronous loading of the history. `ThreadedHistory` was added for this.

- Changes related to `shortcuts.prompt`:

  * There is now a class `PromptSession` which also has a method `prompt`. Both
    the class and the method take about the same arguments. This can be used to
    create a session. Every `prompt` call of the same instance will reuse all
    the arguments given to the class itself.

    The input history is always shared during the entire session.

    Of course, it's still possible to call the global `prompt` function. This
    will create a new `PromptSession` every time when it's called.

  * The `prompt` function now takes a `key_bindings` argument instead of
    `key_bindings_registry`. This should only contain the additional bindings.
    (The default bindings are always included.)

- Changes to the event loops:

  * The event loop API is now closer to how asyncio works. A prompt_toolkit
    `Application` now has a `Future` object. Calling the `.run_async()` method
    creates and returns that `Future`. An event loop has a `run_until_complete`
    method that takes a future and runs the event loop until the Future is set.

    The idea is to be able to transition easily to asyncio when Python 2
    support can be dropped in the future.

  * `Application` still has a method `run()` that underneath still runs the
    event loop until the `Future` is set and returns that result.

  * The asyncio adaptors (like the asyncio event loop integration) now require
    Python 3.5. (We use the async/await syntax internally.)

  * The `Input` and `Output` classes have some changes. (Not really important.)

  * `Application.run_sub_applications` has been removed. The alternative is to
    call `run_coroutine_in_terminal` which returns a `Future`.

- Changes to the `filters` module:

  * The `Application` is no longer passed around, so both `CLIFilter` and
    `SimpleFilter` were merged into `Filter`. `to_cli_filter` and
    `to_simple_filter` became `to_filter`.

  * All filters have been turned into functions. For instance, `IsDone`
    became `is_done` and `HasCompletions` became `has_completions`.

    This was done because almost all classes were called without any arguments
    in the `__init__` causing additional braces everywhere. This means that
    `HasCompletions()` has to be replaced by `has_completions` (without
    parenthesis).

    The few filters that took arguments as input, became functions, but still
    have to be called with the given arguments.

    For new filters, it is recommended to use the `@Condition` decorator,
    rather then inheriting from `Filter`.

- Other renames:

  * `IncrementalSearchDirection` was renamed to `SearchDirection`.
  * The `use_alternate_screen` parameter has been renamed to `full_screen`.
  * `Buffer.initial_document` was renamed to `Buffer.document`.
  * `TokenListControl` has been renamed to `FormattedTextControl`.
  * `Application.set_return_value` has been renamed to `Application.set_result`.

- Other new features:

  * `DummyAutoSuggest` and `DynamicAutoSuggest` were added.
  * `DummyClipboard` and `DynamicClipboard` were added.
  * `DummyCompleter` and `DynamicCompleter` were added.
  * `DummyHistory` and `DynamicHistory` was added.

  * `to_container` and `to_window` utilities were added.


1.0.9: 2016-11-07
-----------------

Fixes:
- Fixed a bug in the `cooked_mode` context manager. This caused a bug in
  ptpython where executing `input()` would display ^M instead of accepting the
  input.
- Handle race condition in eventloop/posix.py
- Updated ANSI color names for vt100. (High and low intensity colors were
  swapped.)

New features:
- Added yank-nth-arg and yank-last-arg readline commands + Emacs bindings.
- Allow searching in Vi selection mode.
- Made text objects of the Vi 'n' and 'N' search bindings. This adds for
  instance the following bindings: cn, cN, dn, dN, yn, yN

1.0.8: 2016-10-16
-----------------

Fixes:
- In 'shortcuts': complete_while_typing was a SimpleFilter, not a CLIFilter.
- Always reset color attributes after rendering.
- Handle bug in Windows when '$TERM' is not defined.
- Ignore errors when calling tcgetattr/tcsetattr.
  (This handles the "Inappropriate ioctl for device" crash in some scenarios.)
- Fix for Windows. Correctly recognize all Chinese and Lithuanian characters.

New features:
- Added shift+left/up/down/right keys.
- Small performance optimization in the renderer.
- Small optimization in the posix event loop. Don't call time.time() if we
  don't have an inputhook. (Less syscalls.)
- Turned the _max_postpone_until argument of call_from_executor into a float.
  (As returned by `time.time`.) This will do less system calls. It's
  backwards-incompatible, but this is still a private API, used only by pymux.)
- Added Shift-I/A commands in Vi block selection mode for inserting text at the
  beginning of each line of the block.
- Refactoring of the 'selectors' module for the posix event loop. (Reuse the
  same selector object in one loop, don't recreate it for each select.)


1.0.7: 2016-08-21
-----------------

Fixes:
- Bugfix in completion. When calculating the common completion to be inserted,
  the new completions were calculated wrong.
- On Windows, avoid extra vertical scrolling if the cursor is already on screen.

New features:
- Support negative arguments for next/previous word ending/beginning.


1.0.6: 2016-08-15
-----------------

Fixes:
- Go to the start of the line in Vi navigation mode, when 'j' or 'k' have been
  pressed to navigate to a new history entry.
- Don't crash when pasting text that contains \r\n characters. (This could
  happen in iTerm2.)
- Python 2.6 compatibility fix.
- Allow pressing <esc> before each -ve argument.
- Better support for conversion from #ffffff values to ANSI colors in
  Vt100_Output.
    * Prefer colors with some saturation, instead of gray colors, if the given
      color was not gray.
    * Prefer a different foreground and background color if they were
      originally not the same. (This avoids concealing text.)

New features:
- Improved ANSI color support.
    * If the $PROMPT_TOOLKIT_ANSI_COLORS_ONLY environment variable has been
      set, use the 16 ANSI colors only.
    * Take an `ansi_colors_only` parameter in `Vt100_Output` and
      `shortcuts.create_output`.


1.0.5: 2016-08-04
-----------------

Fixes:
- Critical fix for running on Windows. The gevent work-around in the inputhook
  caused 'An operation was attempted on something that is not a socket'.


1.0.4: 2016-08-03
-----------------

Fixes:
- Key binding fixes:
      * Improved handling of repeat arguments in Emacs mode. Pressing sequences
        like 'esc---123' do now work (like GNU Readline):
              - repetition of the minus sign is ignored.
              - No esc prefix is required for each digit.
      * Fix in ControlX-ControlX binding.
      * Fix in bracketed paste.
      * Pressing Control-U at the start of the line now deletes the newline.
      * Pressing Control-K at the end of the line, deletes the newline after
        the cursor.
      * Support negative argument for Control-K
      * Fixed cash when left/right were pressed with a negative argument. (In
        Emacs mode.)
      * Fix in ControlUp/ControlDown key bindings.
      * Distinguish backspace from Control-H. They are not the same.
      * Delete in front of the cursor when a negative argument has been given
        to backspace.
      * Handle arrow keys correctly in emacs-term.
- Performance optimizations:
      * Performance optimization in Registry.
      * Several performance optimization in filters.
      * Import asyncio inline (only if required).
- Use the best possible selector in the event loop. This fixes bugs in
  situations where we have too many open file descriptors.
- Fix UI freeze when gevent monkey patch has been applied.
- Fix segmentation fault in Alpine Linux. (Regarding the use of ioctl.)
- Use the correct colors on Windows. (When the foreground/background colors
  have been modified.)
- Display a better error message when running in Idle.
- Additional flags for vt100 inputs: disable flow control.
- Also patch stderr in CommandLineInterface.patch_stdout_context.

New features:
- Allow users to enter Vi digraphs in reverse order.
- Improved autocompletion behavior. See IPython issue #9658.
- Added a 'clear' function in the shortcuts module.

For future compatibility:
- `Keys.Enter` has been added. This is the key that should be bound for
  handling the enter key.

  Right now, prompt_toolkit translates \r into \n during the handling of the
  input; this is not correct and makes it impossible to distinguish between
  ControlJ and ControlM. Some applications bind ControlJ for custom handling of
  the enter key, because this equals \n. However, in a future version we will
  stop replacing \r by \n and at that point, the enter key will be ControlM.
  So better is to use `Keys.Enter`, which becomes an alias for whatever the
  enter key translates into.


1.0.3: 2016-06-20
-----------------

Fixes:
- Bugfix for Python2 in readline-like completion.
- Bugfix in readline-like completion visualization.

New features:
- Added `erase_when_done` parameter to the `Application` class.  (This was
  required for the bug fixes.)
- Added (experimental) `CommandLineInterface.run_application_generator` method.
  (Also required for the bug fix.)

1.0.2: 2016-06-16
-----------------

Fixes:
- Don't select the first completion when `complete_while_typing` is False.
  (Restore the old behavior.)


1.0.1: 2016-06-15
-----------------

Fixes:
- Bugfix in GrammarValidator and SentenceValidator.
- Don't leave the alternate screen on resize events.
- Use errors=surrogateescape, in order to handle mouse events in some
  terminals.
- Ignore key presses in _InterfaceEventLoopCallbacks.feed_key when the CLI is in the done state.
- Bugfix in get_common_complete_suffix. Don't return any suffix when there are
  completions that change whatever is before the cursor.
- Bugfix for Win32/Python2: use unicode literals: This crashed arrow navigation
  on Windows.
- Bugfix in InputProcessor: handling of more complex key bindings.
- Fix: don't apply completions, if there is only one completion which doesn't
  have any effect.
- Fix: correctly handle prompts starting with a newline in
  prompt_toolkit.shortcuts.
- Fix: thread safety in autocomplete code.
- Improve styling for matching brackets. (Allow individual styling for the
  bracket under the cursor and the other.)
- Fix in ShowLeadingWhiteSpaceProcessor/ShowTrailingWhiteSpaceProcessor: take
  output encoding into account. (The signature had to change a little for
  this.)
- Bug fix in key bindings: only activate Emacs system/open-in-editor bindings
  if editing_mode is emacs.
- Added write_binary parameter to Vt100_Output. This fixes a bug in some cases
  where we expect it to write non-encoded strings.
- Fix key bindings for Vi mode registers.

New features (**):
- Added shortcuts.confirm/create_confirm_application function.
- Emulate bracketed paste on Windows. (When the input stream contains multiple
  key presses among which a newline and at least one other character, consider
  this a paste event, and handle as bracketed paste on Unix.
- Added key handler for displaying completions, just like readline does.
- Implemented Vi guu,gUU,g~~ key bindings.
- Implemented Vi 'gJ' key binding.
- Implemented Vi ab,ib,aB,iB text objects.
- Support for ZeroWidthEscape tokens in prompt and token lists. Used to support
  final shell integration.
- Fix: Make document.text/cursor_position/selection read-only. (Changing these
  would break the caching causing bigger issues.)
- Using pytest for unit tests.
- Allow key bindings to have Keys.Any at any possible position. (Not just the
  end.) This made it significantly easier to write the named register Vi
  bindings, resulting in an approved start-up time.)
- Better feedback when entering multi-key key bindings in insert mode. (E.g.
  when 'jj' would be mapped to escape.)
- Small improvement in key processor: allow key bindings to generate new key
  presses.
- Handle ControlUp and ControlDown by default: move to the previous/next record
  in the history.
- Accept 'char'/'get_char' parameters in FillControl.
- Added refresh_interval method to prompt() function.

Performance improvements:
- Improve the performance of test_callable_args: this should significantly
  increase the start-up time.
- Start-up time for creating the Vi bindings has been improved significantly.

(**) Some small backwards-compatible features were allowed for this minor
     release. After evaluating the impact/risk/work involved we concluded that
     we could ship these in a minor release.


1.0.0: 2016-05-05
-----------------

Fixes:
- Adjust minimum completion menu width to match UIControl and Window class.
- Bugfix regarding weakref in InputProcessor.
- Fix for pypy3: bug in WeakValueDictionary.
- Correctly handle '0' key binding in Vi mode.
- Also load Vi bindings by default in Application if no registry has been given.
- Only go into selection mode if the current buffer is not empty.
- Close PipeInput after usage.
- Only use 16 colors in (Emacs) eterm-color.
- Bugfix in "xP Vi key binding.
- Bugfix in Vi { and } key binding.
- Fix: use correct token for Scrollbar in MultiColumnCompletionMenuControl.
- Handle negative values in translate_row_col_to_index.
- Handle decomposed unicode characters.
- Fixed Window.always_hide_cursor. (Parameter was ignored.)
- Fix in zz Vi key binding. (When render info is not available.)
- Fix in Document.get_cursor_up_position. (When an argument is given.)

New features:
- Separated `load_mouse_bindings`.
- Refactoring/simplification of the key bindings: better use of filters and
  CLI.editing_mode.
- Added DummyOutput class and a few unit tests that test the whole CLI.
- Use the bisect module in Document._line_start_indexes instead of a custom
  binary search. This should improve the performance.
- Stay in the same column when doing multiple up/down movements.
- Visual improvements:
  * Implemented cursorcolumn, cursorline and colorcolumn.
  * Only reserve menu space when `complete_while_typing=True` or when there are
    completions to be displayed.
  * Support for chaining tokens for combined styles. SelectedText will now
    reverse the colors from the highlighting by default. Style
    `Token.SelectedText` to set a fixed foreground/background.
    Also for SearchMatch, we now use combined tokens.
  * Support for dark gray on Windows.
  * Default token for SystemToolbar and SearchToolbar.
  * Display selection also on empty lines.
- Emacs key bindings improved:
  * Recognize + handle ControlDelete key.
  * Implemented meta-* and control-backslash key bindings.
- Vi key bindings improved:
  * Handle inclusive and linewise motions properly.
  * Fix g_ motion off by one character, and don't work when cursor is in
    the trailing whitespace part of line.
  * Make a(/a)/i(/i)/... motions. Find enclosing brackets instead of the next
    bracket.
  * Update N% motion according to vim behaviors.
  * Fix | motion off by one character.
  * ge/gE motions go to end of previous word, not start.
  * Added Vi 'gm' key binding.
  * Implemented 'gq' key binding in Vi mode. (Reshape text.)
  * Vi operator/text object separation for key bindings.
  * Added 'ap' (auto-paragraph) text object.
  * Implemented Vi digraphs. ControlK will now insert a digraph.
  * Implemented vi tilde_operator.
  * Support named registers.
  * Vi < and > key bindings became operators.
  * Text objects and motions are now separate bindings.
  * Improved copy/paste in Vi mode.

Backwards-incompatible changes:
- Don't reset the current buffer anymore by default in
  CommandLineInterface.run(). Passing `reset_current_buffer=True` is now
  required.
- Renamed MouseEventTypes to MouseEventType for consistency. The old name is
  still valid, but deprecated.
- Refactoring of Callbacks. All events should now receive one argument, which
  is the sender. (Further, Callback was renamed to Event.) This is mostly used
  internally.
- Moved on_invalidate callback from CommandLineInterface to Application
- Renamed `PipeInput.send` to `PipeInput.send_text`. (Old deprecated name is
  still kept as a valid alias.)
- Renamed SimpleLexer.default_token to SimpleLexer.token. (+
  backwards-compatibility.)
- Refactoring of the filters: `ViStateFilter` has been deprecated. (Should not
  be used anymore.) Use the filters, as defined in prompt_toolkit.filters.
- `editing_mode` is now a property of `CommandLineInterface`. This is replacing
  the `vi_mode` parameter in `KeyBindingManager`.
- The default accept_action for the default Buffer in Application now becomes
  IGNORE. This is a much more sensible default. Pass RETURN_DOCUMENT to get
  the previous behavior,
- Always expect an EventLoop instance in CommandLineInterface. Creating it in
  __init__ caused a memory leak.


0.60: 2016-03-14
----------------

Fixes:
- Fix in Document.paste. (The screen was not updated after an undo of a paste.)
- Don't use deprecated inspect.getargspec on Python 3.
- Fixed reading input on Windows when input was piped in stdin.
- Use correct file descriptors for input/output in run_system_command.
- Always correctly split prompt in shortcuts.prompt. (Even when multiline=False)
- Correctly align right prompt to the top when the left prompt consists of
  multiple lines.
- Correctly use Token.Transparent as default token for a TokenListControl.
- Fix in syntax synchronization. (Better handle the case when no
  synchronization point was found.)
- Send SIGTSTP to the whole process group.
- Correctly raise on_buffer_changed on all text changes.
- Fix in regular_languages.GrammarLexer. (Fixes bug in ptipython syntax
  highlighting.)

New features:
- Add support for additional readers to the Win32 event loop.
- Added on_render event.
- Carry the weight in layout dimensions to allow stretching.


0.59: 2016-02-27
----------------

Fixes:
- Set correct default color on Windows. (Gray instead of high intensity gray.)
- Reverse colors on Windows when foreground/background color have not been
  specified.
- Correct handling of mouse events for FillControl.
- Take margin into account when calculating Window height. (Fixes bug in
  multiline prompt.)
- Handle division by zero in UIContent.get_height_for_text.


0.58: 2016-02-23
----------------

Fixes:
- Correctly return result for mouse handler in TokenListControl.
- Bugfix in meta-backspace key binding. (Delete all whitespace before the
  cursor, when there is only whitespace.)
- Bugfix in Vi gu, gU, g? and g~ key bindings (in selection mode).
- Correctly restore default console attributes on Windows.
- Disable bracketed paste support in ConEmu. (This was broken.)
- When an unknown exception is raised in `CommandLineInterface.run()`, don't
  forget to redraw the CLI.

New features:
- Many performance improvements and better caching. (Especially in the
  `Document` class.)
- Support for continuation tokens in `shortcuts.prompt` and
  `shortcuts.create_prompt_layout`.
- Added `shortcuts.print_tokens` function for printing colored output.
- Sound bell when nothing was deleted.
- Added escape sequences for F1-F5 keys on the Linux console.
- Improved support for the Linux console. (Switch back to 16 colors.)
- Added F13-F24 input codes for xterm.
- Created prompt_toolkit.token. A custom Token implementation, that is
  compatible with Pygments.token. (This way, Pygments becomes an optional
  dependency. For many use cases, nothing except the Token class from Pygments
  was used, so it was a bit overkill to install Pygments for only that.)
- Refactoring of prompt_toolkit.styles.
- `Float` objects got a `hide_when_covering_content` option.
- Implementation of RPROMPT, like ZSH: Added `get_rprompt_tokens` to
  `create_prompt_layout`.
- Some improvements to the default style.
- Also handle Ctrl-R and Ctrl-S in Vi mode when searching.
- Added TabsProcessor: a tool to visualize tabs instead of displaying ^I.
- Give a better error message when trying to run in git-bash.
- Support for ANSI color names in style dictionaries.

- Big refactoring of the `Window` and `UIControl` classes. This should result
  in huge performance improvements on big inputs. (While first, a document
  could have 1,000 lines; now it can have about 100,000 lines on the same system.)

  The Window and UIControl have been rewritten very much. Rather than each time
  rendering the whole user control, we now only have to render the visible part.

  Because of this, many pieces had to be rewritten:
  - UIControls work differently. They return a `UIContent` instance that
    consist of a collection of lines.
  - All processors have been rewritten. (Their API changed as well, because
    they process one line at a time.)
  - Lexers work differently. `Lexer.lex_document` should now return a function
    that returns the tokens for one line. PygmentsLexer has been optimized that
    it becomes 'lazy', and it has optional syntax synchronization. That means,
    that the lexer doesn't have to start the lexing at the beginning of the
    document. (Which would be slow for big documents.)

Backwards-incompatible changes:
- As mentioned above, the refactoring of `Window` and `UIControl` caused many
  "internal" APIs to change. All custom `UIControl`, `Processor` and `Lexer`
  classes have to be rewritten. However, for most applications this should not
  be an issue. Especially, the `shortcuts.prompt` function is
  backwards-compatible.
- `wrap_lines` became a property of `Window` instead of `BufferControl`.


0.57: 2016-01-04
----------------

Fixes:
- Made `max_render_postpone_time` configurable. The current default was bad.
  (We should probably always draw the UI once every cycle of the event loop.)


0.56: 2016-01-03
----------------

Fixes:
- Fix in bracketed paste. It was not correctly enabled for each prompt.


0.55: 2016-01-03
----------------

New features:
- Implemented bracketed paste mode. (This allows much faster pasting, as well
  as pasting without going into paste mode. This makes sure that indentation in
  ptpython for instance is kept correctly.)
- Added support for italic output and blink. (For terminals that support it.)
- Added get_horizontal_scroll, get_vertical_scroll and always_hide_cursor
  parameters to Window.
- Refactoring of the posix event loop. Better scheduling of all tasks/FDs to
  avoid starvation. (Everything should feel more responsive in high CPU
  situations.)
- Added get_default_char function to TokenListControl.
- AppendAutoSuggestion now accepts a token parameter.
- Support for ansi color names in styles.
- Accept get_width/get_height parameters in Float.
- Added Output.write_raw and accept 'raw' parameter in
  CommandLineInterface.stdout_proxy.
- Better caching of tokens in TokenListControl.
- Add mouse support to TokenListControl.
- Display "Window too small" when the window becomes too small.
- Added 'bell' function to Output.
- Accept weights in HSplit/VSplit.
- Added Registry.remove_binding method to dynamically remove key bindings.
- Added focus_on_click parameter to BufferControl.
- Introduced BufferMapping class as a wrapper around the buffers dictionary.
  This one also contains the focus stack.
- Improved 'v' and 'V' key bindings. Allow switching between line and character
  selection modes.
- Added layout.highlighters. A new, much faster way to do selection and search
  highlighting.
- Make search_state dynamic for key bindings.
- Added 'sentence' option to WordCompleter.
- Cache Document.lines for better performance.
- Implementation of BLOCK selections. (Cut, copy, paste.)
- Accept a 'reserve_space_for_menu' parameter in the shortcuts. (This is an
  integer.)
- Support for 24bit true color on vt100 terminals.
- Added CommandLineInterface.on_invalidate event.
- Added __version__ to __init__.py.

Fixes:
- Always show cursor in the 'done' state.
- Allow HSplit to have zero children.
- Bugfix for handling of backslash on Windows with some non-us keyboards.
  (Ptpython issue #28.)
- Never render characters outside the visible screen region.
- Fix in WordCompleter. When case insensitive and input contained uppercase.
- Highlight search match when the cursor is at any position on the match. (not
  just the beginning.)

Backwards-incompatible changes:
(Most changes will probably not have an impact on external applications.)
- Change in the `Style` API. This allows caching of Attrs in renderer and
  faster rendering.  (Style now has a get_attrs_for_token instead of a
  get_token_to_attributes_dict method.)
- Removed DefaultStyle. Created PygmentsStyle.from_defaults class method instead.
- Removed AbortAction.IGNORE. This was ambiguous.
- Accept 'cli' parameter in 'walk' and 'find_window_for_buffer_name'.
- The focus stack is now stored in BufferMapping.
- ViStateFilter and KeyBindingManager now accept a get_vi_state callable
  instead of vi_state itself. (This way a key bindings registry becomes
  stateless.)
- HighlightSearchProcessor and HighlightSelectionProcessor became deprecated.
  (Use highlighters instead.)


0.54: 2015-10-29
----------------

New features:
- Allow CommandLineInterface to run in any thread.
- Hide cursor while rendering.
- Added add_reader/remove_reader methods to EventLoop.
- Support for 'reverse' style.
- Redraw more lazy, by using invalidate.
- Added show_cursor property to Screen.
- Center or right align text in TokenListControl also when it spans multiple
  lines.

Fixes:
- Bugfix in PathCompleter. (Expanduser issue.)
- Fix in signal handler.
- Use utf-8 encoding in Vt100_Output by default.
- Use correct default token in BufferControl.
- Fix in ControlL key binding. Use @handle to allow deactivation.

Backwards-incompatible changes:
- Renamed create_default_layout to create_prompt_layout
- Renamed create_default_application to create_prompt_application
- Renamed Layout to Container.
- Renamed CommandLineInterfaces.request_redraw to invalidate.
- Changed the actual value of SEARCH_BUFFER, DEFAULT_BUFFER, SYSTEM_BUFFER and
  DUMMY_BUFFER.
- Changed order of keyword arguments of the BufferControl class. "buffer_name"
  now comes first.
- Removed old pt(i)python code.

0.53: 2015-10-06
----------------

New features:
- Handling of the insert key in Vi mode.
- Added 'zt' and 'zb' Vi key bindings.
- Added delete key binding for deleting selected text.
- Select word below cursor on double mouse click.
- Added `wrap_lines` option to TokenListControl.
- Added `KeyBindingManager.for_prompt`.

Fixes:
- Fix in rendering output.
- Reset renderer correctly in run_in_terminal.
- Only reset buffer when using `AbortAction.RETRY`.
- Fix in handling of exit (Ctrl-D) key presses.
- Fix in `CompleteEvent`. Correctly set `completion_requested`.

Backwards-incompatible changes:
- Renamed `ValidationError.index` to `ValidationError.cursor_position`.
- Renamed `shortcuts.get_input` to `shortcuts.prompt`.
- Return empty string instead of None in
  `Document.current_char`/`char_before_cursor`.


0.52: 2015-09-24
----------------

Fixes:
- Fix in auto suggestion: hide suggestion when accepting input.


0.51: 2015-09-24
----------------

New features:
- Mouse support. (Scrolling and clicking for vt100 terminals. For Windows only
  clicking.) Both the autocompletion menus and buffer controls respond to
  scrolling and clicking.
- Added auto suggestions. (Like the fish shell.)
- Stdout proxy become thread safe.
- Linewrapping can now be disabled, instead we get horizontal scrolling.
- Line numbering can now be relative. Like the vi 'relativenumber' option.

Fixes:
- Fixed excessive scrolling in Windows.
- Bugfix in search highlighting.
- Copy all words during repetition of Ctrl-W presses.
- The 'libs' folder has been removed.
- Fix in MultiColumnCompletionsMenu: don't create very big columns.

Backwards-incompatible changes:
- Disable search by default in KeyBindingManager.
- Separated abort/exit key bindings. Disabled by default in KeyBindingManager.
- 'Ignore' became the default on_abort action in `Application`.
- 'Ignore' became the default accept_action in `Buffer`.
- The layout processors have been refactored. The API is changed.
- `SwitchableValidator` has been renamed to `ConditionalValidator`.
- `WindowRenderInfo` has several incompatible changes.
- Margins have been refactored completely. Now it's the window that has the
  margin instead of `BufferControl`. Is is both much more performant and
  flexible.


0.50: 2015-09-06
----------------

Fix:
- Leaving of alternate screen on Windows.


0.49: 2015-09-06
----------------

New features:
- Added MANIFEST.in
- Better support for multiline prompts in shortcuts.
- Added Document.set_document method.
- Added 'default' argument to `shortcuts.create_default_application`.
- Added `align_center` option for `TokenListControl`.
- Added optional key bindings for full page navigation. (Moved key bindings
  from pyvim into prompt-toolkit.)
- Accepts default_char in BufferControl for filling the background.
- Added InFocusStack filter.

Fixes:
- Small fix in TokenListControl: use the right Char for aligning.

Backwards-incompatible changes:
- Removed deprecated 'tokens' attribute from GrammarLexer.


0.48: 2015-09-02
----------------

New features:
- run_in_terminal now returns the result of the called function.
- Made history attribute of Buffer class public.
- Added support for sub CommandLineInterfaces.
- Accept optional vi_state parameter in KeyBindingManager.

Fixes:
- Pop-up menu positioning. The menu was shown too often above instead of below
  the cursor.
- Fix in Control-W key binding. When there is only whitespace before the
  cursor, delete the whitespace.
- Rendering bug fix in open_in_editor: run editor using cli.run_in_terminal.
- Fix in renderer. Correctly reserve the vertical space as required by the
  layout.
- Small fix in Margin ABC.
- Added __iter__ to History ABC.
- Small bugfix in CommandLineInterface: create correct eventloop when no
  eventloop was given.
- Never schedule a second repaint operation when a previous was not yet
  executed.


0.47: 2015-08-19
----------------

New features:
- Added `prompt_toolkit.layout.utils.iter_token_lines`.
- Allow `None` values on the focus stack.
- Buffers can be readonly. Added `IsReadOnly` filter.
- `eager` behavior for key bindings. When a key binding is eager it will be
  executed as soon as it's matched, even when there is another binding that
  starts with this key sequence.
- Custom margins for BufferControl.

Fixes:
- Don't trigger autocompletion on paste.
- Added `pre_run` parameter to CommandLineInterface.
- Correct invalidation of BeforeInput and AfterInput.
- Correctly handle transparency. (For floats.)
- Small change in the algorithm to determine Window dimensions: keep in the
  bounds of the Window dimensions.

Backwards-incompatible changes:
- There a now a `Lexer` abstract base class. Every lexer should be an instance
  of that class, and Pygments lexers should be wrapped in a `PygmentsLexer`
  class. `prompt_toolkit.shortcuts` still accepts Pygments lexers directly for
  backwards-compatibility.
- BufferControl no longer has a `show_line_numbers` argument. Pass a
  `NumberedMargin` instance instead.
- The `History` class became an abstract base class and only defines an
  interface. The default history class is now called `InMemoryHistory`.


0.46: 2015-08-08
----------------

New features:
- By default, in shortcuts, only show search highlighting when the search is
  the current input buffer.
- Accept 'count' for all search operations. (For repetition.)
- `shortcuts.create_default_layout` accepts a `multiline` parameter.
- Show meta display text for completions also in multi-column mode.

Fixes:
- Correct invalidation of DefaultPrompt when search direction changes.
- Correctly include/exclude current cursor position in search.
- More consistency in styles.
- Fix in ConditionalProcessor.has_focus.
- Python 2.6 compatibility fix.
- Show cursor at the correct position during reverse-i-search.
- Fixed stdout encoding bug for vt100 output.

Backwards-incompatible changes:
- Use of `ConditionalContainer` everywhere. The `Window` class no longer
  accepts a `filter` argument to decide about the visibility. Instead
  wrapping inside a `ConditionalContainer` class is required.


0.45: 2015-07-30
----------------

Fixes:
- Bug fix on OS X: correctly detect platform as not Windows.


0.44: 2015-07-30
----------------

Fixes:
- Fixed bug in eventloops: handle timeout correctly, even when there is an eventhook.
- Bug fix in open-in-editor: set correct cursor position.

New features:
- CompletionsMenu got a scroll_offset.
- Use 256 colors and ANSI sequences when ConEmu ANSI support has been detected.
- Added PyperclipClipboard for synchronization with the system clipboard.
  and clipboard parameter in shortcut functions.
- Filter for enabling/disabling handling of Vi 'v' binding.


0.43: 2015-07-15
----------------

Fixes:
- Windows bug fix. STD_INPUT_HANDLE should be c_ulong instead of HANDLE.
  (This caused crashes on some systems.)

New features:
- Added eventloop and patch_stdout parameters to get_input.
- Inputhook support added.
- Added ShowLeadingWhiteSpaceProcessor and ShowTrailingWhiteSpaceProcessor
  processors.
- Accept Filter as multiline parameter in 'shortcuts'.
- MultiColumnCompletionsMenu + display_completions_in_columns parameter
  in shortcuts.

Backwards incompatible changes:
- Layout.width was renamed to preferred_width and now receives a
  max_available_width parameter.


0.42: 2015-06-25
----------------

Fixes:
- Support for Windows cmder and conemu consoles.
- Correct handling of unicode input and output on Windows.

New features:
- Support terminal titles.
- Handle Control-Enter as Meta-Enter on Windows.
- Control-Z key binding for Windows.
- Implemented alternate screen buffer on Windows.
- Clipboard became an ABC and InMemoryClipboard default implementation.


0.41: 2015-06-20
----------------

Fixes:
- Emacs Control-T key binding.
- Color fix for Windows consoles.

New features:
- Allow both booleans and Filters in many places.
- `password` can be a Filter now.


0.40: 2015-06-15
----------------

Fixes:
- Fix in output_screen_diff: reset correctly.
- Ignore flush errors in vt100_output.
- Implemented <num>gg Vi key binding.
- Bug fix in the renderer when the style changes.

New features:
- TokenListControl can now display the cursor somewhere.
- Added SwitchableValidator class.
- print_tokens function added.
- get_style argument for Application added.
- KeyBindingManager got an enable_all argument.

Backwards incompatible changes:
- history_search is now a SimpleFilter instance.


0.39: 2015-06-04
----------------

Fixes:
- Fixed layout.py example.
- Fixed eventloop for Python 64bit on Windows.
- Fix in history.
- Fix in key bindings.


0.38: 2015-05-31
----------------

New features:
- Improved performance significantly for processing key bindings.
  (Pasting text will be a lot faster.)
- Added 'M' Vi key binding.
- Added 'z-' and 'z+' and 'z-[Enter]' Vi keybindings.
- Correctly handle input and output encodings on Windows.

Bug fixes:
- Fix bug when completion cursor position is outside range of current text.
- Don't crash Control-D is pressed while waiting for ENTER press (in run_system_command.)
- On Ctrl-Z, don't suspend on Windows, where we don't have SIGTSTP.
- Ignore result when open_in_editor received a nonzero return code.
- Bug fix in displaying of menu meta information. Don't show 'None'.

Backwards incompatible changes:
- Refactoring of the I/O layer.  Separation of the CommandLineInterface
  and Application class.
- Renamed enable_system_prompt to enable_system_bindings.

0.37: 2015-05-11
----------------

New features:
- Handling of trailing input in contrib.regular_languages.

Bug fixes:
- Default message in shortcuts.get_input.
- Windows compatibility for contrib.telnet.
- OS X bugfix in contrib.telnet.

0.36: 2015-05-09
----------------

New features:
- Added get_prompt_tokens parameter to create_default_layout.
- Show prompt in bold by default.

Bug fixes:
- Correct cache invalidation of DefaultPrompt.
- Using text_type assertions in contrib.telnet.
- Removed contrib.shortcuts completely. (The .pyc files still
  appeared incorrectly in the wheel.)

0.35: 2015-05-07
----------------

New features:
- WORD parameter for WordCompleter.
- DefaultPrompt.from_message constructor.
- Added reactive.py for simple integer data binding.
- Implemented scroll_offset and scroll_beyond_bottom for Window.
- Some performance improvements.

Bug fixes:
- Handling of relative path in PathCompleter.
- unicode_literals for all examples.
- Visibility of bottom toolbar in create_default_layout shortcut.
- Correctly handle 'J' vi key binding.
- Fix in indent/unindent.
- Better Vi bindings in visual mode.

Backwards incompatible changes:
- Moved prompt_toolkit.contrib.shortcuts to prompt_toolkit.shortcuts.
- Refactoring of contrib.telnet.

0.34: 2015-04-26
----------------

Bug fixes:
- Correct display of multi width characters in completion menu.

Backwards incompatible changes:
- Renamed Buffer.add_to_history to Buffer.append_to_history.

0.33: 2015-04-25
----------------

Bug fixes:
- Crash fixed in SystemCompleter when some directories didn't exist.
- Made text/cursor_position in Document more atomic.
- Fixed Char.__ne__, improves performance.
- Better performance of the filter module.
- Refactoring of the filter module.
- Bugfix in BufferControl, caching was not done correctly.
- fixed 'zz' Vi key binding.

New features:
- Do tilde expansion for system commands.
- Added ignore_case option for CommandLineInterface.

Backwards incompatible changes:
- complete_while_typing parameter has been moved from CommandLineInterface to
  Buffer.


0.32: 2015-04-22
----------------

New features:
- Implemented repeat arg for '{' and '}' vi key binding.
- Added autocorrection example.
- first experimental telnet interface added.
- Added contrib.validators.SentenceValidator.
- Added Layout.walk generator to traverse the layout.
- Improved 'L' and 'H' Vi key bindings.
- Implemented Vi 'zz' key binding.
- ValidationToolbar got a show_position parameter.
- When only width or height are given for a float, the control is centered in
  the parent.
- Added beforeKeyPress and afterKeyPress events.
- Added HighlightMatchingBracketProcessor.
- SearchToolbar got a vi_mode option to show '?' and '/' instead of 'I-search'.
- Implemented vi '*' binding.
- Added onBufferChanged event to CommandLineInterface.
- Many performance improvements: some caching and not rendering after every
  single key stroke.
- Added ConditionalProcessor.
- Floating menus are now shown above the cursor, when below is not enough
  space, but above is enough space.
- Improved vi 'G' key binding.
- WindowRenderInfo got a full_height_visible, top_visible, and a few other
  attributes.
- PathCompleter got an expanduser option to do tilde expansion.

Fixed:
- Always insert indentation when pressing enter.
- vertical_scroll should be an int instead of a float.
- Some bug fixes in renderer.Output.
- Pressing backspace in an empty search in Vi mode now goes back to navigation
  mode.
- Bug fix in TokenListControl (Correctly calculate height for multiline
  content.)
- Only apply HighlightMatchingBracketProcessor when editing buffer.
- Ensure that floating layouts never go out of bounds.
- Home/End now go to the start and end of the line.
- Fixed vi 'c' key binding.
- Redraw the whole output when the style changes.
- Don't trigger onTextInsert when working_index doesn't change.
- Searching now wraps around the start/end of buffer/history.
- Don't go to the start of the line when moving forward in history.

Changes:
- Don't show directory/file/link in the meta information of PathCompleter anymore.
- Complete refactoring of the event loops.
- Refactoring of the Renderer and CommandLineInterface class.
- CommandLineInterface now accepts an optional Output argument.
- CommandLineInterface now accepts a use_alternate_screen parameter.
- Moved highlighting code for search/selection from BufferControl to processors.
- Completers are now always run asynchronously.
- Complete refactoring of the search. (Most responsibility move out of Buffer
  class. CommandLineInterface now got a search_state attribute.)

Backwards incompatible changes:
- get_input does now have a history attribute instead of history_filename.
- EOFError and KeyboardInterrupt is raised for abort and exit instead of custom
  exceptions.
- CommandLineInterface does no longer have a property 'is_reading_input'.
- filters.AlwaysOn/AlwaysOff have been renamed to Always/Never.
- AcceptAction has been moved from CommandLineInterface to Buffer. Now every
  buffer can define its own accept action.
- CommandLineInterface now expects an Eventloop instance in __init__.


0.31: 2015-01-30
----------------

Fixed:
- Bug in float positioning
- Show completion menu only for the default_buffer in get_input.

New features:
- PathCompleter got a get_paths parameter.
- PathCompleter sorts alphabetically.
- Added contrib.completers.SystemCompleter
- Completion got a get_display_meta parameter.


0.30: 2015-01-26
----------------

Fixed:
- Backward compatibility with django_extensions.
- Usage of alternate screen in the renderer.

New features:
- Vi '#' key binding.
- contrib.shortcuts.get_input got a get_bottom_toolbar_tokens argument.
- Separate key bindings for "open in editor." KeyBindingManager got a
  enable_open_in_editor argument.

0.28: 2015-01-25
----------------

Fixed:
- syntax error in 0.27

0.27: 2015-01-25
----------------

Backwards-incompatible changes:
- Complete refactoring of the layout system. (HSplit, VSplit, FloatContainer)
  as well as a list of controls (TokenListControl, BufferControl) in order to
  design much more complex layouts.
- ptpython code has been moved to a separate repository.

New features:
- prompt_toolkit.contrib.shortcuts.get_input has been extended.

Fixed:
- Behavior of Control+left/right/up/down.
- Backspace in incremental search.
- Hide completion menu correctly when the cursor position changes.

0.26: 2015-01-08
----------------

Backwards-incompatible changes:
- Refactoring of the key input system. (The registry which contains the key
  bindings, the focus stack, key binding manager.) Overall much better API.
- Renamed `Line` to `Buffer`.

New features:
- Added filters as a way of disabling/enabling parts of the runtime according
  to certain conditions.
- Global clipboard, shared between all buffers.
- Added (experimental) "merge history" feature to ptpython.
- Added 'C-x r k' and 'C-x r y' emacs key bindings for cut and paste.
- Added g_, ge and gE vi key bindings.
- Added support for handling control + arrows keys.

Fixed:
- Correctly handle f1-f4 in rxvt-unicode.

0.25: 2014-12-11
----------------

Fixed:
- Package did not install on Python 2.6/2.7.

0.24: 2014-12-10
----------------

Backwards-incompatible changes:
- Completer.get_completions now gets a complete_event argument.

New features:
- For ptpython: filename completion inside Python strings.
- prompt_toolkit.contrib.regular_languages added.
- prompt_toolkit.contrib.pdb added. (Experimental PDB front-end.)
- Support for multiline toolbars.
- asyncio support added. (Integration with asyncio event loop.)
- WORD parameter added to Document.word_before_cursor.

Fixed:
- Small fixes in Win32 terminal output.
- Bug fix in parsing of CPR response.

0.23: 2014-11-28
----------------

New features:
- contrib.completers added.

Fixed:
- Improved j/k key bindings in Vi mode.
- Don't leak internal variables into ptipython shell.
- Initialize IPython extensions.
- Use IPython's prompt.
- Workarounds for Jedi crashes.

0.22: 2014-11-09
----------------

Fixed:
- Fixed missing import which caused Ctrl-Z to crash.
- Show error message for ptipython when IPython is not installed.

0.21: 2014-10-25
----------------
New features:
- Using entry_points in setup.py
- Experimental Win32 support added.

Fixed:
- Behavior of 'r' and 'R' key bindings in Vi mode.
- Detect multiline correctly for ptpython when there are triple quoted strings.
- Some other small improvements.


0.20: 2014-10-04
----------------
Fixed:
- Workarounds for Jedi bugs.
- Better handling of window resize events.
- Fixed counter in ptipython prompt.
- Use IPythonInputSplitter.transform_cell for IPython syntax validation.
- Only insert newlines for open brackets if the cursor is at the end of the input string.

New features:
- More Vi key bindings: 'B', 'W', 'E', 'aW', 'aw' and 'iW'
- ControlZ now suspends the process


0.19: 2014-09-30
----------------
Fixed:
- Handle Jedi crashes.
- Autocompletion in `ptipython`
- Input validation in `ptipython`
- Execution of system commands (in `ptpython`) in Python 3
- Add current directory to sys.path for `ptpython`.
- Minimal jedi and six version in setup.py

New features
- Python 2.6 support
- C-C> and C-C< indent and unindent emacs key bindings.
- `ptpython` can now also run python scripts, so aliasing of `ptpython` as
  `python` will work better.

0.18: 2014-09-29
----------------
- First official (beta) release.


Jan 25, 2014
------------
first commit