""" Line editing functionality. --------------------------- This provides a UI for a line input, similar to GNU Readline, libedit and linenoise. Either call the `prompt` function for every line input. Or create an instance of the :class:`.PromptSession` class and call the `prompt` method from that class. In the second case, we'll have a 'session' that keeps all the state like the history in between several calls. There is a lot of overlap between the arguments taken by the `prompt` function and the `PromptSession` (like `completer`, `style`, etcetera). There we have the freedom to decide which settings we want for the whole 'session', and which we want for an individual `prompt`. Example:: # Simple `prompt` call. result = prompt('Say something: ') # Using a 'session'. s = PromptSession() result = s.prompt('Say something: ') """ from __future__ import unicode_literals from prompt_toolkit.application import Application from prompt_toolkit.application.current import get_app from prompt_toolkit.auto_suggest import DynamicAutoSuggest from prompt_toolkit.buffer import Buffer from prompt_toolkit.clipboard import DynamicClipboard, InMemoryClipboard from prompt_toolkit.completion import DynamicCompleter, ThreadedCompleter from prompt_toolkit.document import Document from prompt_toolkit.enums import DEFAULT_BUFFER, SEARCH_BUFFER, EditingMode from prompt_toolkit.eventloop import ensure_future, Return, From from prompt_toolkit.filters import is_done, has_focus, renderer_height_is_known, to_filter, Condition, has_arg from prompt_toolkit.formatted_text import to_formatted_text from prompt_toolkit.history import InMemoryHistory from prompt_toolkit.input.defaults import get_default_input from prompt_toolkit.key_binding.bindings.auto_suggest import load_auto_suggest_bindings from prompt_toolkit.key_binding.bindings.completion import display_completions_like_readline from prompt_toolkit.key_binding.bindings.open_in_editor import load_open_in_editor_bindings from prompt_toolkit.key_binding.key_bindings import KeyBindings, DynamicKeyBindings, merge_key_bindings, ConditionalKeyBindings, KeyBindingsBase from prompt_toolkit.keys import Keys from prompt_toolkit.layout import Window, HSplit, FloatContainer, Float from prompt_toolkit.layout.containers import ConditionalContainer, WindowAlign from prompt_toolkit.layout.controls import BufferControl, SearchBufferControl, FormattedTextControl from prompt_toolkit.layout.dimension import Dimension from prompt_toolkit.layout.layout import Layout from prompt_toolkit.layout.margins import PromptMargin, ConditionalMargin from prompt_toolkit.layout.menus import CompletionsMenu, MultiColumnCompletionsMenu from prompt_toolkit.layout.processors import DynamicProcessor, PasswordProcessor, ConditionalProcessor, AppendAutoSuggestion, HighlightIncrementalSearchProcessor, HighlightSelectionProcessor, DisplayMultipleCursors, BeforeInput, ReverseSearchProcessor, ShowArg, merge_processors from prompt_toolkit.layout.utils import explode_text_fragments from prompt_toolkit.lexers import DynamicLexer from prompt_toolkit.output.defaults import get_default_output from prompt_toolkit.styles import BaseStyle, DynamicStyle from prompt_toolkit.utils import suspend_to_background_supported from prompt_toolkit.validation import DynamicValidator from prompt_toolkit.widgets.toolbars import ValidationToolbar, SystemToolbar, SearchToolbar from six import text_type import contextlib import threading import time __all__ = [ 'PromptSession', 'prompt', 'confirm', 'create_confirm_session', # Used by '_display_completions_like_readline'. 'CompleteStyle', ] def _split_multiline_prompt(get_prompt_text): """ Take a `get_prompt_text` function and return three new functions instead. One that tells whether this prompt consists of multiple lines; one that returns the fragments to be shown on the lines above the input; and another one with the fragments to be shown at the first line of the input. """ def has_before_fragments(): for fragment, char in get_prompt_text(): if '\n' in char: return True return False def before(): result = [] found_nl = False for fragment, char in reversed(explode_text_fragments(get_prompt_text())): if found_nl: result.insert(0, (fragment, char)) elif char == '\n': found_nl = True return result def first_input_line(): result = [] for fragment, char in reversed(explode_text_fragments(get_prompt_text())): if char == '\n': break else: result.insert(0, (fragment, char)) return result return has_before_fragments, before, first_input_line class _RPrompt(Window): " The prompt that is displayed on the right side of the Window. " def __init__(self, get_formatted_text): super(_RPrompt, self).__init__( FormattedTextControl(get_formatted_text), align=WindowAlign.RIGHT, style='class:rprompt') def _true(value): " Test whether `value` is True. In case of a Filter, call it. " return to_filter(value)() class CompleteStyle: " How to display autocompletions for the prompt. " COLUMN = 'COLUMN' MULTI_COLUMN = 'MULTI_COLUMN' READLINE_LIKE = 'READLINE_LIKE' class PromptSession(object): """ PromptSession for a prompt application, which can be used as a GNU Readline replacement. This is a wrapper around a lot of ``prompt_toolkit`` functionality and can be a replacement for `raw_input`. All parameters that expect "formatted text" can take either just plain text (a unicode object), a list of ``(style_str, text)`` tuples or an HTML object. Example usage:: s = PromptSession(message='>') text = s.prompt() :param message: Plain text or formatted text to be shown before the prompt. This can also be a callable that returns formatted text. :param multiline: `bool` or :class:`~prompt_toolkit.filters.Filter`. When True, prefer a layout that is more adapted for multiline input. Text after newlines is automatically indented, and search/arg input is shown below the input, instead of replacing the prompt. :param wrap_lines: `bool` or :class:`~prompt_toolkit.filters.Filter`. When True (the default), automatically wrap long lines instead of scrolling horizontally. :param is_password: Show asterisks instead of the actual typed characters. :param editing_mode: ``EditingMode.VI`` or ``EditingMode.EMACS``. :param vi_mode: `bool`, if True, Identical to ``editing_mode=EditingMode.VI``. :param complete_while_typing: `bool` or :class:`~prompt_toolkit.filters.Filter`. Enable autocompletion while typing. :param validate_while_typing: `bool` or :class:`~prompt_toolkit.filters.Filter`. Enable input validation while typing. :param enable_history_search: `bool` or :class:`~prompt_toolkit.filters.Filter`. Enable up-arrow parting string matching. :param search_ignore_case: :class:`~prompt_toolkit.filters.Filter`. Search case insensitive. :param lexer: :class:`~prompt_toolkit.lexers.Lexer` to be used for the syntax highlighting. :param validator: :class:`~prompt_toolkit.validation.Validator` instance for input validation. :param completer: :class:`~prompt_toolkit.completion.Completer` instance for input completion. :param complete_in_thread: `bool` or :class:`~prompt_toolkit.filters.Filter`. Run the completer code in a background thread in order to avoid blocking the user interface. For ``CompleteStyle.READLINE_LIKE``, this setting has no effect. There we always run the completions in the main thread. :param reserve_space_for_menu: Space to be reserved for displaying the menu. (0 means that no space needs to be reserved.) :param auto_suggest: :class:`~prompt_toolkit.auto_suggest.AutoSuggest` instance for input suggestions. :param style: :class:`.Style` instance for the color scheme. :param include_default_pygments_style: `bool` or :class:`~prompt_toolkit.filters.Filter`. Tell whether the default styling for Pygments lexers has to be included. By default, this is true, but it is recommended to be disabled if another Pygments style is passed as the `style` argument, otherwise, two Pygments styles will be merged. :param enable_system_prompt: `bool` or :class:`~prompt_toolkit.filters.Filter`. Pressing Meta+'!' will show a system prompt. :param enable_suspend: `bool` or :class:`~prompt_toolkit.filters.Filter`. Enable Control-Z style suspension. :param enable_open_in_editor: `bool` or :class:`~prompt_toolkit.filters.Filter`. Pressing 'v' in Vi mode or C-X C-E in emacs mode will open an external editor. :param history: :class:`~prompt_toolkit.history.History` instance. :param clipboard: :class:`~prompt_toolkit.clipboard.Clipboard` instance. (e.g. :class:`~prompt_toolkit.clipboard.InMemoryClipboard`) :param rprompt: Text or formatted text to be displayed on the right side. This can also be a callable that returns (formatted) text. :param bottom_toolbar: Formatted text or callable which is supposed to return formatted text. :param prompt_continuation: Text that needs to be displayed for a multiline prompt continuation. This can either be formatted text or a callable that the width as input and returns formatted text. :param complete_style: ``CompleteStyle.COLUMN``, ``CompleteStyle.MULTI_COLUMN`` or ``CompleteStyle.READLINE_LIKE``. :param mouse_support: `bool` or :class:`~prompt_toolkit.filters.Filter` to enable mouse support. :param default: The default input text to be shown. (This can be edited by the user). :param refresh_interval: (number; in seconds) When given, refresh the UI every so many seconds. :param inputhook: None or an Inputhook callable that takes an `InputHookContext` object. """ _fields = ( 'message', 'lexer', 'completer', 'complete_in_thread', 'is_password', 'editing_mode', 'key_bindings', 'is_password', 'bottom_toolbar', 'style', 'color_depth', 'include_default_pygments_style', 'rprompt', 'multiline', 'prompt_continuation', 'wrap_lines', 'enable_history_search', 'search_ignore_case', 'complete_while_typing', 'validate_while_typing', 'complete_style', 'mouse_support', 'auto_suggest', 'clipboard', 'validator', 'refresh_interval', 'input_processors', 'default', 'enable_system_prompt', 'enable_suspend', 'enable_open_in_editor', 'reserve_space_for_menu', 'tempfile_suffix', 'inputhook') def __init__( self, message='', default='', multiline=False, wrap_lines=True, is_password=False, vi_mode=False, editing_mode=EditingMode.EMACS, complete_while_typing=True, validate_while_typing=True, enable_history_search=False, search_ignore_case=False, lexer=None, enable_system_prompt=False, enable_suspend=False, enable_open_in_editor=False, validator=None, completer=None, complete_in_thread=False, reserve_space_for_menu=8, complete_style=None, auto_suggest=None, style=None, color_depth=None, include_default_pygments_style=True, history=None, clipboard=None, prompt_continuation=None, rprompt=None, bottom_toolbar=None, mouse_support=False, input_processors=None, key_bindings=None, erase_when_done=False, tempfile_suffix='.txt', inputhook=None, refresh_interval=0, input=None, output=None): assert style is None or isinstance(style, BaseStyle) assert input_processors is None or isinstance(input_processors, list) assert key_bindings is None or isinstance(key_bindings, KeyBindingsBase) # Defaults. output = output or get_default_output() input = input or get_default_input() history = history or InMemoryHistory() clipboard = clipboard or InMemoryClipboard() # Ensure backwards-compatibility, when `vi_mode` is passed. if vi_mode: editing_mode = EditingMode.VI # Store all settings in this class. self.input = input self.output = output # Store all settings in this class. for name in self._fields: if name not in ('editing_mode', ): value = locals()[name] setattr(self, name, value) # Create buffers, layout and Application. self.history = history self.default_buffer = self._create_default_buffer() self.search_buffer = self._create_search_buffer() self.layout = self._create_layout() self.app = self._create_application(editing_mode, erase_when_done) def _dyncond(self, attr_name): """ Dynamically take this setting from this 'PromptSession' class. `attr_name` represents an attribute name of this class. Its value can either be a boolean or a `Filter`. This returns something that can be used as either a `Filter` or `Filter`. """ @Condition def dynamic(): value = getattr(self, attr_name) return to_filter(value)() return dynamic def _create_default_buffer(self): """ Create and return the default input buffer. """ dyncond = self._dyncond # Create buffers list. def accept(buff): """ Accept the content of the default buffer. This is called when the validation succeeds. """ self.app.exit(result=buff.document.text) # Reset content before running again. self.app.pre_run_callables.append(buff.reset) return Buffer( name=DEFAULT_BUFFER, # Make sure that complete_while_typing is disabled when # enable_history_search is enabled. (First convert to Filter, # to avoid doing bitwise operations on bool objects.) complete_while_typing=Condition(lambda: _true(self.complete_while_typing) and not _true(self.enable_history_search) and not self.complete_style == CompleteStyle.READLINE_LIKE), validate_while_typing=dyncond('validate_while_typing'), enable_history_search=dyncond('enable_history_search'), validator=DynamicValidator(lambda: self.validator), completer=DynamicCompleter(lambda: ThreadedCompleter(self.completer) if self.complete_in_thread and self.completer else self.completer), history=self.history, auto_suggest=DynamicAutoSuggest(lambda: self.auto_suggest), accept_handler=accept, tempfile_suffix=lambda: self.tempfile_suffix) def _create_search_buffer(self): return Buffer(name=SEARCH_BUFFER) def _create_layout(self): """ Create `Layout` for this prompt. """ dyncond = self._dyncond # Create functions that will dynamically split the prompt. (If we have # a multiline prompt.) has_before_fragments, get_prompt_text_1, get_prompt_text_2 = \ _split_multiline_prompt(self._get_prompt) default_buffer = self.default_buffer search_buffer = self.search_buffer # Create processors list. all_input_processors = [ HighlightIncrementalSearchProcessor(), HighlightSelectionProcessor(), ConditionalProcessor(AppendAutoSuggestion(), has_focus(default_buffer) & ~is_done), ConditionalProcessor(PasswordProcessor(), dyncond('is_password')), DisplayMultipleCursors(), # Users can insert processors here. DynamicProcessor(lambda: merge_processors(self.input_processors or [])), # For single line mode, show the prompt before the input. ConditionalProcessor( merge_processors([ BeforeInput(get_prompt_text_2), ShowArg(), ]), ~dyncond('multiline')) ] # Create bottom toolbars. bottom_toolbar = ConditionalContainer( Window(FormattedTextControl( lambda: self.bottom_toolbar, style='class:bottom-toolbar.text'), style='class:bottom-toolbar', dont_extend_height=True, height=Dimension(min=1)), filter=~is_done & renderer_height_is_known & Condition(lambda: self.bottom_toolbar is not None)) search_toolbar = SearchToolbar( search_buffer, ignore_case=dyncond('search_ignore_case')) search_buffer_control = SearchBufferControl( buffer=search_buffer, input_processors=[ ReverseSearchProcessor(), ShowArg(), ], ignore_case=dyncond('search_ignore_case')) system_toolbar = SystemToolbar( enable_global_bindings=dyncond('enable_system_prompt')) def get_search_buffer_control(): " Return the UIControl to be focused when searching start. " if _true(self.multiline): return search_toolbar.control else: return search_buffer_control default_buffer_control = BufferControl( buffer=default_buffer, search_buffer_control=get_search_buffer_control, input_processors=all_input_processors, include_default_input_processors=False, lexer=DynamicLexer(lambda: self.lexer), preview_search=True) default_buffer_window = Window( default_buffer_control, height=self._get_default_buffer_control_height, left_margins=[ # In multiline mode, use the window margin to display # the prompt and continuation fragments. ConditionalMargin( PromptMargin(get_prompt_text_2, self._get_continuation), filter=dyncond('multiline'), ) ], wrap_lines=dyncond('wrap_lines')) @Condition def multi_column_complete_style(): return self.complete_style == CompleteStyle.MULTI_COLUMN # Build the layout. layout = HSplit([ # The main input, with completion menus floating on top of it. FloatContainer( HSplit([ ConditionalContainer( Window( FormattedTextControl(get_prompt_text_1), dont_extend_height=True), Condition(has_before_fragments) ), ConditionalContainer( default_buffer_window, Condition(lambda: get_app().layout.current_control != search_buffer_control), ), ConditionalContainer( Window(search_buffer_control), Condition(lambda: get_app().layout.current_control == search_buffer_control), ), ]), [ # Completion menus. Float(xcursor=True, ycursor=True, content=CompletionsMenu( max_height=16, scroll_offset=1, extra_filter=has_focus(default_buffer) & ~multi_column_complete_style)), Float(xcursor=True, ycursor=True, content=MultiColumnCompletionsMenu( show_meta=True, extra_filter=has_focus(default_buffer) & multi_column_complete_style)), # The right prompt. Float(right=0, top=0, hide_when_covering_content=True, content=_RPrompt(lambda: self.rprompt)), ] ), ConditionalContainer( ValidationToolbar(), filter=~is_done), ConditionalContainer( system_toolbar, dyncond('enable_system_prompt') & ~is_done), # In multiline mode, we use two toolbars for 'arg' and 'search'. ConditionalContainer( Window(FormattedTextControl(self._get_arg_text), height=1), dyncond('multiline') & has_arg), ConditionalContainer(search_toolbar, dyncond('multiline') & ~is_done), bottom_toolbar, ]) return Layout(layout, default_buffer_window) def _create_application(self, editing_mode, erase_when_done): """ Create the `Application` object. """ dyncond = self._dyncond # Default key bindings. auto_suggest_bindings = load_auto_suggest_bindings() open_in_editor_bindings = load_open_in_editor_bindings() prompt_bindings = self._create_prompt_bindings() # Create application application = Application( layout=self.layout, style=DynamicStyle(lambda: self.style), include_default_pygments_style=dyncond('include_default_pygments_style'), clipboard=DynamicClipboard(lambda: self.clipboard), key_bindings=merge_key_bindings([ merge_key_bindings([ auto_suggest_bindings, ConditionalKeyBindings(open_in_editor_bindings, dyncond('enable_open_in_editor') & has_focus(DEFAULT_BUFFER)), prompt_bindings ]), DynamicKeyBindings(lambda: self.key_bindings), ]), mouse_support=dyncond('mouse_support'), editing_mode=editing_mode, erase_when_done=erase_when_done, reverse_vi_search_direction=True, color_depth=lambda: self.color_depth, # I/O. input=self.input, output=self.output) # During render time, make sure that we focus the right search control # (if we are searching). - This could be useful if people make the # 'multiline' property dynamic. ''' def on_render(app): multiline = _true(self.multiline) current_control = app.layout.current_control if multiline: if current_control == search_buffer_control: app.layout.current_control = search_toolbar.control app.invalidate() else: if current_control == search_toolbar.control: app.layout.current_control = search_buffer_control app.invalidate() app.on_render += on_render ''' return application def _create_prompt_bindings(self): """ Create the KeyBindings for a prompt application. """ kb = KeyBindings() handle = kb.add default_focused = has_focus(DEFAULT_BUFFER) @Condition def do_accept(): return (not _true(self.multiline) and self.app.layout.has_focus(DEFAULT_BUFFER)) @handle('enter', filter=do_accept & default_focused) def _(event): " Accept input when enter has been pressed. " self.default_buffer.validate_and_handle() @Condition def readline_complete_style(): return self.complete_style == CompleteStyle.READLINE_LIKE @handle('tab', filter=readline_complete_style & default_focused) def _(event): " Display completions (like Readline). " display_completions_like_readline(event) @handle('c-c', filter=default_focused) def _(event): " Abort when Control-C has been pressed. " event.app.exit(exception=KeyboardInterrupt, style='class:aborting') @Condition def ctrl_d_condition(): """ Ctrl-D binding is only active when the default buffer is selected and empty. """ app = get_app() return (app.current_buffer.name == DEFAULT_BUFFER and not app.current_buffer.text) @handle('c-d', filter=ctrl_d_condition & default_focused) def _(event): " Exit when Control-D has been pressed. " event.app.exit(exception=EOFError, style='class:exiting') suspend_supported = Condition(suspend_to_background_supported) @Condition def enable_suspend(): return to_filter(self.enable_suspend)() @handle('c-z', filter=suspend_supported & enable_suspend) def _(event): """ Suspend process to background. """ event.app.suspend_to_background() return kb @contextlib.contextmanager def _auto_refresh_context(self): " Return a context manager for the auto-refresh loop. " done = [False] # nonlocal # Enter. def run(): while not done[0]: time.sleep(self.refresh_interval) self.app.invalidate() if self.refresh_interval: t = threading.Thread(target=run) t.daemon = True t.start() try: yield finally: # Exit. done[0] = True def prompt( self, message=None, # When any of these arguments are passed, this value is overwritten # for the current prompt. default='', editing_mode=None, refresh_interval=None, vi_mode=None, lexer=None, completer=None, complete_in_thread=None, is_password=None, key_bindings=None, bottom_toolbar=None, style=None, color_depth=None, include_default_pygments_style=None, rprompt=None, multiline=None, prompt_continuation=None, wrap_lines=None, enable_history_search=None, search_ignore_case=None, complete_while_typing=None, validate_while_typing=None, complete_style=None, auto_suggest=None, validator=None, clipboard=None, mouse_support=None, input_processors=None, reserve_space_for_menu=None, enable_system_prompt=None, enable_suspend=None, enable_open_in_editor=None, tempfile_suffix=None, inputhook=None, async_=False): """ Display the prompt. All the arguments are a subset of the :class:`~.PromptSession` class itself. This will raise ``KeyboardInterrupt`` when control-c has been pressed (for abort) and ``EOFError`` when control-d has been pressed (for exit). :param async_: When `True` return a `Future` instead of waiting for the prompt to finish. """ # Backup original settings. backup = dict((name, getattr(self, name)) for name in self._fields) # Take settings from 'prompt'-arguments. for name in self._fields: value = locals()[name] if value is not None: setattr(self, name, value) if vi_mode: self.editing_mode = EditingMode.VI def restore(): " Restore original settings. " for name in self._fields: setattr(self, name, backup[name]) def run_sync(): with self._auto_refresh_context(): try: self.default_buffer.reset(Document(self.default)) return self.app.run(inputhook=self.inputhook) finally: restore() def run_async(): with self._auto_refresh_context(): try: self.default_buffer.reset(Document(self.default)) result = yield From(self.app.run_async()) raise Return(result) finally: restore() if async_: return ensure_future(run_async()) else: return run_sync() @property def editing_mode(self): return self.app.editing_mode @editing_mode.setter def editing_mode(self, value): self.app.editing_mode = value def _get_default_buffer_control_height(self): # If there is an autocompletion menu to be shown, make sure that our # layout has at least a minimal height in order to display it. if (self.completer is not None and self.complete_style != CompleteStyle.READLINE_LIKE): space = self.reserve_space_for_menu else: space = 0 if space and not get_app().is_done: buff = self.default_buffer # Reserve the space, either when there are completions, or when # `complete_while_typing` is true and we expect completions very # soon. if buff.complete_while_typing() or buff.complete_state is not None: return Dimension(min=space) return Dimension() def _get_prompt(self): return to_formatted_text(self.message, style='class:prompt') def _get_continuation(self, width, line_number, is_soft_wrap): """ Insert the prompt continuation. :param width: The width that's available for the continuation (don't exceed this). :param line_number: :param is_soft_wrap: True when we got a soft wrap here instead of a hard line ending. """ prompt_continuation = self.prompt_continuation if callable(prompt_continuation): prompt_continuation = prompt_continuation(width, line_number, is_soft_wrap) return to_formatted_text( prompt_continuation, style='class:prompt-continuation') def _get_arg_text(self): arg = self.app.key_processor.arg if arg == '-': arg = '-1' return [ ('class:arg-toolbar', 'Repeat: '), ('class:arg-toolbar.text', arg) ] def prompt(*a, **kw): """ The global `prompt` function. This will create a new `PromptSession` instance for every call. """ # Input and output arguments have to be passed to the 'PromptSession' # class, not its method. input = kw.pop('input', None) output = kw.pop('output', None) session = PromptSession(input=input, output=output) return session.prompt(*a, **kw) prompt.__doc__ = PromptSession.prompt.__doc__ def create_confirm_session(message): """ Create a `PromptSession` object for the 'confirm' function. """ assert isinstance(message, text_type) bindings = KeyBindings() @bindings.add('y') @bindings.add('Y') def yes(event): session.default_buffer.text = 'y' event.app.exit(result=True) @bindings.add('n') @bindings.add('N') @bindings.add('c-c') def no(event): session.default_buffer.text = 'n' event.app.exit(result=False) @bindings.add(Keys.Any) def _(event): " Disallow inserting other text. " pass session = PromptSession(message, key_bindings=bindings) return session def confirm(message='Confirm (y or n) '): """ Display a confirmation prompt that returns True/False. """ session = create_confirm_session(message) return session.prompt()