cpython/Lib/_pyrepl/completing_reader.py

291 lines
9.5 KiB
Python

# Copyright 2000-2010 Michael Hudson-Doyle <micahel@gmail.com>
# Antonio Cuni
#
# All Rights Reserved
#
#
# Permission to use, copy, modify, and distribute this software and
# its documentation for any purpose is hereby granted without fee,
# provided that the above copyright notice appear in all copies and
# that both that copyright notice and this permission notice appear in
# supporting documentation.
#
# THE AUTHOR MICHAEL HUDSON DISCLAIMS ALL WARRANTIES WITH REGARD TO
# THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
# RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
# CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
from __future__ import annotations
from dataclasses import dataclass, field
import re
from . import commands, console, reader
from .reader import Reader
# types
Command = commands.Command
if False:
from .types import KeySpec, CommandName
def prefix(wordlist: list[str], j: int = 0) -> str:
d = {}
i = j
try:
while 1:
for word in wordlist:
d[word[i]] = 1
if len(d) > 1:
return wordlist[0][j:i]
i += 1
d = {}
except IndexError:
return wordlist[0][j:i]
return ""
STRIPCOLOR_REGEX = re.compile(r"\x1B\[([0-9]{1,3}(;[0-9]{1,2})?)?[m|K]")
def stripcolor(s: str) -> str:
return STRIPCOLOR_REGEX.sub('', s)
def real_len(s: str) -> int:
return len(stripcolor(s))
def left_align(s: str, maxlen: int) -> str:
stripped = stripcolor(s)
if len(stripped) > maxlen:
# too bad, we remove the color
return stripped[:maxlen]
padding = maxlen - len(stripped)
return s + ' '*padding
def build_menu(
cons: console.Console,
wordlist: list[str],
start: int,
use_brackets: bool,
sort_in_column: bool,
) -> tuple[list[str], int]:
if use_brackets:
item = "[ %s ]"
padding = 4
else:
item = "%s "
padding = 2
maxlen = min(max(map(real_len, wordlist)), cons.width - padding)
cols = int(cons.width / (maxlen + padding))
rows = int((len(wordlist) - 1)/cols + 1)
if sort_in_column:
# sort_in_column=False (default) sort_in_column=True
# A B C A D G
# D E F B E
# G C F
#
# "fill" the table with empty words, so we always have the same amout
# of rows for each column
missing = cols*rows - len(wordlist)
wordlist = wordlist + ['']*missing
indexes = [(i % cols) * rows + i // cols for i in range(len(wordlist))]
wordlist = [wordlist[i] for i in indexes]
menu = []
i = start
for r in range(rows):
row = []
for col in range(cols):
row.append(item % left_align(wordlist[i], maxlen))
i += 1
if i >= len(wordlist):
break
menu.append(''.join(row))
if i >= len(wordlist):
i = 0
break
if r + 5 > cons.height:
menu.append(" %d more... " % (len(wordlist) - i))
break
return menu, i
# this gets somewhat user interface-y, and as a result the logic gets
# very convoluted.
#
# To summarise the summary of the summary:- people are a problem.
# -- The Hitch-Hikers Guide to the Galaxy, Episode 12
#### Desired behaviour of the completions commands.
# the considerations are:
# (1) how many completions are possible
# (2) whether the last command was a completion
# (3) if we can assume that the completer is going to return the same set of
# completions: this is controlled by the ``assume_immutable_completions``
# variable on the reader, which is True by default to match the historical
# behaviour of pyrepl, but e.g. False in the ReadlineAlikeReader to match
# more closely readline's semantics (this is needed e.g. by
# fancycompleter)
#
# if there's no possible completion, beep at the user and point this out.
# this is easy.
#
# if there's only one possible completion, stick it in. if the last thing
# user did was a completion, point out that he isn't getting anywhere, but
# only if the ``assume_immutable_completions`` is True.
#
# now it gets complicated.
#
# for the first press of a completion key:
# if there's a common prefix, stick it in.
# irrespective of whether anything got stuck in, if the word is now
# complete, show the "complete but not unique" message
# if there's no common prefix and if the word is not now complete,
# beep.
# common prefix -> yes no
# word complete \/
# yes "cbnu" "cbnu"
# no - beep
# for the second bang on the completion key
# there will necessarily be no common prefix
# show a menu of the choices.
# for subsequent bangs, rotate the menu around (if there are sufficient
# choices).
class complete(commands.Command):
def do(self) -> None:
r: CompletingReader
r = self.reader # type: ignore[assignment]
last_is_completer = r.last_command_is(self.__class__)
immutable_completions = r.assume_immutable_completions
completions_unchangable = last_is_completer and immutable_completions
stem = r.get_stem()
if not completions_unchangable:
r.cmpltn_menu_choices = r.get_completions(stem)
completions = r.cmpltn_menu_choices
if not completions:
r.error("no matches")
elif len(completions) == 1:
if completions_unchangable and len(completions[0]) == len(stem):
r.msg = "[ sole completion ]"
r.dirty = True
r.insert(completions[0][len(stem):])
else:
p = prefix(completions, len(stem))
if p:
r.insert(p)
if last_is_completer:
r.cmpltn_menu_visible = True
r.cmpltn_message_visible = False
r.cmpltn_menu, r.cmpltn_menu_end = build_menu(
r.console, completions, r.cmpltn_menu_end,
r.use_brackets, r.sort_in_column)
r.dirty = True
elif not r.cmpltn_menu_visible:
r.cmpltn_message_visible = True
if stem + p in completions:
r.msg = "[ complete but not unique ]"
r.dirty = True
else:
r.msg = "[ not unique ]"
r.dirty = True
class self_insert(commands.self_insert):
def do(self) -> None:
r: CompletingReader
r = self.reader # type: ignore[assignment]
commands.self_insert.do(self)
if r.cmpltn_menu_visible:
stem = r.get_stem()
if len(stem) < 1:
r.cmpltn_reset()
else:
completions = [w for w in r.cmpltn_menu_choices
if w.startswith(stem)]
if completions:
r.cmpltn_menu, r.cmpltn_menu_end = build_menu(
r.console, completions, 0,
r.use_brackets, r.sort_in_column)
else:
r.cmpltn_reset()
@dataclass
class CompletingReader(Reader):
"""Adds completion support"""
### Class variables
# see the comment for the complete command
assume_immutable_completions = True
use_brackets = True # display completions inside []
sort_in_column = False
### Instance variables
cmpltn_menu: list[str] = field(init=False)
cmpltn_menu_visible: bool = field(init=False)
cmpltn_message_visible: bool = field(init=False)
cmpltn_menu_end: int = field(init=False)
cmpltn_menu_choices: list[str] = field(init=False)
def __post_init__(self) -> None:
super().__post_init__()
self.cmpltn_reset()
for c in (complete, self_insert):
self.commands[c.__name__] = c
self.commands[c.__name__.replace('_', '-')] = c
def collect_keymap(self) -> tuple[tuple[KeySpec, CommandName], ...]:
return super().collect_keymap() + (
(r'\t', 'complete'),)
def after_command(self, cmd: Command) -> None:
super().after_command(cmd)
if not isinstance(cmd, (complete, self_insert)):
self.cmpltn_reset()
def calc_screen(self) -> list[str]:
screen = super().calc_screen()
if self.cmpltn_menu_visible:
ly = self.lxy[1]
screen[ly:ly] = self.cmpltn_menu
self.screeninfo[ly:ly] = [(0, [])]*len(self.cmpltn_menu)
self.cxy = self.cxy[0], self.cxy[1] + len(self.cmpltn_menu)
return screen
def finish(self) -> None:
super().finish()
self.cmpltn_reset()
def cmpltn_reset(self) -> None:
self.cmpltn_menu = []
self.cmpltn_menu_visible = False
self.cmpltn_message_visible = False
self.cmpltn_menu_end = 0
self.cmpltn_menu_choices = []
def get_stem(self) -> str:
st = self.syntax_table
SW = reader.SYNTAX_WORD
b = self.buffer
p = self.pos - 1
while p >= 0 and st.get(b[p], SW) == SW:
p -= 1
return ''.join(b[p+1:self.pos])
def get_completions(self, stem: str) -> list[str]:
return []