diff options
Diffstat (limited to 'src/prompt_toolkit/key_binding/bindings/completion.py')
| -rw-r--r-- | src/prompt_toolkit/key_binding/bindings/completion.py | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/src/prompt_toolkit/key_binding/bindings/completion.py b/src/prompt_toolkit/key_binding/bindings/completion.py new file mode 100644 index 0000000..016821f --- /dev/null +++ b/src/prompt_toolkit/key_binding/bindings/completion.py @@ -0,0 +1,205 @@ +""" +Key binding handlers for displaying completions. +""" +from __future__ import annotations + +import asyncio +import math +from typing import TYPE_CHECKING + +from prompt_toolkit.application.run_in_terminal import in_terminal +from prompt_toolkit.completion import ( + CompleteEvent, + Completion, + get_common_complete_suffix, +) +from prompt_toolkit.formatted_text import StyleAndTextTuples +from prompt_toolkit.key_binding.key_bindings import KeyBindings +from prompt_toolkit.key_binding.key_processor import KeyPressEvent +from prompt_toolkit.keys import Keys +from prompt_toolkit.utils import get_cwidth + +if TYPE_CHECKING: + from prompt_toolkit.application import Application + from prompt_toolkit.shortcuts import PromptSession + +__all__ = [ + "generate_completions", + "display_completions_like_readline", +] + +E = KeyPressEvent + + +def generate_completions(event: E) -> None: + r""" + Tab-completion: where the first tab completes the common suffix and the + second tab lists all the completions. + """ + b = event.current_buffer + + # When already navigating through completions, select the next one. + if b.complete_state: + b.complete_next() + else: + b.start_completion(insert_common_part=True) + + +def display_completions_like_readline(event: E) -> None: + """ + Key binding handler for readline-style tab completion. + This is meant to be as similar as possible to the way how readline displays + completions. + + Generate the completions immediately (blocking) and display them above the + prompt in columns. + + Usage:: + + # Call this handler when 'Tab' has been pressed. + key_bindings.add(Keys.ControlI)(display_completions_like_readline) + """ + # Request completions. + b = event.current_buffer + if b.completer is None: + return + complete_event = CompleteEvent(completion_requested=True) + completions = list(b.completer.get_completions(b.document, complete_event)) + + # Calculate the common suffix. + common_suffix = get_common_complete_suffix(b.document, completions) + + # One completion: insert it. + if len(completions) == 1: + b.delete_before_cursor(-completions[0].start_position) + b.insert_text(completions[0].text) + # Multiple completions with common part. + elif common_suffix: + b.insert_text(common_suffix) + # Otherwise: display all completions. + elif completions: + _display_completions_like_readline(event.app, completions) + + +def _display_completions_like_readline( + app: Application[object], completions: list[Completion] +) -> asyncio.Task[None]: + """ + Display the list of completions in columns above the prompt. + This will ask for a confirmation if there are too many completions to fit + on a single page and provide a paginator to walk through them. + """ + from prompt_toolkit.formatted_text import to_formatted_text + from prompt_toolkit.shortcuts.prompt import create_confirm_session + + # Get terminal dimensions. + term_size = app.output.get_size() + term_width = term_size.columns + term_height = term_size.rows + + # Calculate amount of required columns/rows for displaying the + # completions. (Keep in mind that completions are displayed + # alphabetically column-wise.) + max_compl_width = min( + term_width, max(get_cwidth(c.display_text) for c in completions) + 1 + ) + column_count = max(1, term_width // max_compl_width) + completions_per_page = column_count * (term_height - 1) + page_count = int(math.ceil(len(completions) / float(completions_per_page))) + # Note: math.ceil can return float on Python2. + + def display(page: int) -> None: + # Display completions. + page_completions = completions[ + page * completions_per_page : (page + 1) * completions_per_page + ] + + page_row_count = int(math.ceil(len(page_completions) / float(column_count))) + page_columns = [ + page_completions[i * page_row_count : (i + 1) * page_row_count] + for i in range(column_count) + ] + + result: StyleAndTextTuples = [] + + for r in range(page_row_count): + for c in range(column_count): + try: + completion = page_columns[c][r] + style = "class:readline-like-completions.completion " + ( + completion.style or "" + ) + + result.extend(to_formatted_text(completion.display, style=style)) + + # Add padding. + padding = max_compl_width - get_cwidth(completion.display_text) + result.append((completion.style, " " * padding)) + except IndexError: + pass + result.append(("", "\n")) + + app.print_text(to_formatted_text(result, "class:readline-like-completions")) + + # User interaction through an application generator function. + async def run_compl() -> None: + "Coroutine." + async with in_terminal(render_cli_done=True): + if len(completions) > completions_per_page: + # Ask confirmation if it doesn't fit on the screen. + confirm = await create_confirm_session( + f"Display all {len(completions)} possibilities?", + ).prompt_async() + + if confirm: + # Display pages. + for page in range(page_count): + display(page) + + if page != page_count - 1: + # Display --MORE-- and go to the next page. + show_more = await _create_more_session( + "--MORE--" + ).prompt_async() + + if not show_more: + return + else: + app.output.flush() + else: + # Display all completions. + display(0) + + return app.create_background_task(run_compl()) + + +def _create_more_session(message: str = "--MORE--") -> PromptSession[bool]: + """ + Create a `PromptSession` object for displaying the "--MORE--". + """ + from prompt_toolkit.shortcuts import PromptSession + + bindings = KeyBindings() + + @bindings.add(" ") + @bindings.add("y") + @bindings.add("Y") + @bindings.add(Keys.ControlJ) + @bindings.add(Keys.ControlM) + @bindings.add(Keys.ControlI) # Tab. + def _yes(event: E) -> None: + event.app.exit(result=True) + + @bindings.add("n") + @bindings.add("N") + @bindings.add("q") + @bindings.add("Q") + @bindings.add(Keys.ControlC) + def _no(event: E) -> None: + event.app.exit(result=False) + + @bindings.add(Keys.Any) + def _ignore(event: E) -> None: + "Disable inserting of text." + + return PromptSession(message, key_bindings=bindings, erase_when_done=True) |