From cfedcd1318107ed79d27d518b4cd1be9ebd7cf40 Mon Sep 17 00:00:00 2001 From: Matt Wozniski Date: Tue, 11 Jun 2024 12:42:10 -0400 Subject: [PATCH] gh-119517: Fixes for pasting in pyrepl (GH-120253) * Remove pyrepl's optimization for self-insert This will be replaced by a less specialized optimization. * Use line-buffering when pyrepl echoes pastes Previously echoing was totally suppressed until the entire command had been pasted and the terminal ended paste mode, but this gives the user no feedback to indicate that an operation is in progress. Drawing something to the screen once per line strikes a balance between perceived responsiveness and performance. * Remove dead code from pyrepl `msg_at_bottom` is always true. * Speed up pyrepl's screen rendering computation The Reader in pyrepl doesn't hold a complete representation of the screen area being drawn as persistent state. Instead, it recomputes it, on each keypress. This is fast enough for a few hundred bytes, but incredibly slow as the input buffer grows into the kilobytes (likely because of pasting). Rather than making some expensive and expansive changes to the repl's internal representation of the screen, add some caching: remember some data from one refresh to the next about what was drawn to the screen and, if we don't find anything that has invalidated the results that were computed last time around, reuse them. To keep this caching as simple as possible, all we'll do is look for lines in the buffer that were above the cursor the last time we were asked to update the screen, and that are still above the cursor now. We assume that nothing can affect a line that comes before both the old and new cursor location without us being informed. Based on this assumption, we can reuse old lines, which drastically speeds up the overwhelmingly common case where the user is typing near the end of the buffer. * Speed up pyrepl prompt drawing Cache the `can_colorize()` call rather than repeatedly recomputing it. This call looks up an environment variable, and is called once per character typed at the REPL. The environment variable lookup shows up as a hot spot when profiling, and we don't expect this to change while the REPL is running. * Speed up pasting multiple lines into the REPL Previously, we were checking whether the command should be accepted each time a line break was encountered, but that's not the expected behavior. In bracketed paste mode, we expect everything pasted to be part of a single block of code, and encountering a newline shouldn't behave like a user pressing to execute a command. The user should always have a chance to review the pasted command before running it. * Use a read buffer for input in pyrepl Previously we were reading one byte at a time, which causes much slower IO than necessary. Instead, read in chunks, processing previously read data before asking for more. * Optimize finding width of a single character `wlen` finds the width of a multi-character string by adding up the width of each character, and then subtracting the width of any escape sequences. It's often called for single character strings, however, which can't possibly contain escape sequences. Optimize for that case. * Optimize disp_str for ASCII characters Since every ASCII character is known to display as single width, we can avoid not only the Unicode data lookup in `disp_str` but also the one hidden in `str_width` for them. * Speed up cursor movements in long pyrepl commands When the current pyrepl command buffer contains many lines, scrolling up becomes slow. We have optimizations in place to reuse lines above the cursor position from one refresh to the next, but don't currently try to reuse lines below the cursor position in the same way, so we wind up with quadratic behavior where all lines of the buffer below the cursor are recomputed each time the cursor moves up another line. Optimize this by only computing one screen's worth of lines beyond the cursor position. Any lines beyond that can't possibly be shown by the console, and bounding this makes scrolling up have linear time complexity instead. --------- (cherry picked from commit 32a0faba439b239d7b0c242c1e3cd2025c52b8cf) Co-authored-by: Matt Wozniski Signed-off-by: Matt Wozniski Co-authored-by: Pablo Galindo --- Lib/_pyrepl/commands.py | 3 - Lib/_pyrepl/completing_reader.py | 8 +- Lib/_pyrepl/reader.py | 154 ++++++++++++++++++++++--------- Lib/_pyrepl/readline.py | 4 + Lib/_pyrepl/unix_console.py | 20 +++- Lib/_pyrepl/utils.py | 2 + 6 files changed, 134 insertions(+), 57 deletions(-) diff --git a/Lib/_pyrepl/commands.py b/Lib/_pyrepl/commands.py index 6bffed1bfe9327..c3fce91013b001 100644 --- a/Lib/_pyrepl/commands.py +++ b/Lib/_pyrepl/commands.py @@ -368,8 +368,6 @@ def do(self) -> None: r = self.reader text = self.event * r.get_arg() r.insert(text) - if len(text) == 1 and r.pos == len(r.buffer): - r.calc_screen = r.append_to_screen class insert_nl(EditCommand): @@ -483,4 +481,3 @@ def do(self) -> None: self.reader.paste_mode = False self.reader.in_bracketed_paste = False self.reader.dirty = True - self.reader.calc_screen = self.reader.calc_complete_screen diff --git a/Lib/_pyrepl/completing_reader.py b/Lib/_pyrepl/completing_reader.py index 8df35ccb9117b1..05770aaf5060cc 100644 --- a/Lib/_pyrepl/completing_reader.py +++ b/Lib/_pyrepl/completing_reader.py @@ -209,10 +209,6 @@ def do(self) -> None: r = self.reader # type: ignore[assignment] commands.self_insert.do(self) - - if r.cmpltn_menu_visible or r.cmpltn_message_visible: - r.calc_screen = r.calc_complete_screen - if r.cmpltn_menu_visible: stem = r.get_stem() if len(stem) < 1: @@ -261,8 +257,8 @@ def after_command(self, cmd: Command) -> None: if not isinstance(cmd, (complete, self_insert)): self.cmpltn_reset() - def calc_complete_screen(self) -> list[str]: - screen = super().calc_complete_screen() + 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 diff --git a/Lib/_pyrepl/reader.py b/Lib/_pyrepl/reader.py index 255967e2fcf96c..20eff916ec4d67 100644 --- a/Lib/_pyrepl/reader.py +++ b/Lib/_pyrepl/reader.py @@ -35,15 +35,13 @@ # types Command = commands.Command if False: - from typing import Callable from .types import Callback, SimpleContextManager, KeySpec, CommandName - CalcScreen = Callable[[], list[str]] def disp_str(buffer: str) -> tuple[str, list[int]]: """disp_str(buffer:string) -> (string, [int]) - Return the string that should be the printed represenation of + Return the string that should be the printed representation of |buffer| and a list detailing where the characters of |buffer| get used up. E.g.: @@ -54,11 +52,17 @@ def disp_str(buffer: str) -> tuple[str, list[int]]: b: list[int] = [] s: list[str] = [] for c in buffer: - if ord(c) > 128 and unicodedata.category(c).startswith("C"): + if ord(c) < 128: + s.append(c) + b.append(1) + elif unicodedata.category(c).startswith("C"): c = r"\u%04x" % ord(c) - s.append(c) - b.append(wlen(c)) - b.extend([0] * (len(c) - 1)) + s.append(c) + b.append(str_width(c)) + b.extend([0] * (len(c) - 1)) + else: + s.append(c) + b.append(str_width(c)) return "".join(s), b @@ -230,7 +234,6 @@ class Reader: commands: dict[str, type[Command]] = field(default_factory=make_default_commands) last_command: type[Command] | None = None syntax_table: dict[str, int] = field(default_factory=make_default_syntax_table) - msg_at_bottom: bool = True keymap: tuple[tuple[str, str], ...] = () input_trans: input.KeymapTranslator = field(init=False) input_trans_stack: list[input.KeymapTranslator] = field(default_factory=list) @@ -238,8 +241,52 @@ class Reader: screeninfo: list[tuple[int, list[int]]] = field(init=False) cxy: tuple[int, int] = field(init=False) lxy: tuple[int, int] = field(init=False) - calc_screen: CalcScreen = field(init=False) scheduled_commands: list[str] = field(default_factory=list) + can_colorize: bool = False + + ## cached metadata to speed up screen refreshes + @dataclass + class RefreshCache: + in_bracketed_paste: bool = False + screen: list[str] = field(default_factory=list) + screeninfo: list[tuple[int, list[int]]] = field(init=False) + line_end_offsets: list[int] = field(default_factory=list) + pos: int = field(init=False) + cxy: tuple[int, int] = field(init=False) + dimensions: tuple[int, int] = field(init=False) + + def update_cache(self, + reader: Reader, + screen: list[str], + screeninfo: list[tuple[int, list[int]]], + ) -> None: + self.in_bracketed_paste = reader.in_bracketed_paste + self.screen = screen.copy() + self.screeninfo = screeninfo.copy() + self.pos = reader.pos + self.cxy = reader.cxy + self.dimensions = reader.console.width, reader.console.height + + def valid(self, reader: Reader) -> bool: + dimensions = reader.console.width, reader.console.height + dimensions_changed = dimensions != self.dimensions + paste_changed = reader.in_bracketed_paste != self.in_bracketed_paste + return not (dimensions_changed or paste_changed) + + def get_cached_location(self, reader: Reader) -> tuple[int, int]: + offset = 0 + earliest_common_pos = min(reader.pos, self.pos) + num_common_lines = len(self.line_end_offsets) + while num_common_lines > 0: + offset = self.line_end_offsets[num_common_lines - 1] + if earliest_common_pos > offset: + break + num_common_lines -= 1 + else: + offset = 0 + return offset, num_common_lines + + last_refresh_cache: RefreshCache = field(default_factory=RefreshCache) def __post_init__(self) -> None: # Enable the use of `insert` without a `prepare` call - necessary to @@ -252,53 +299,60 @@ def __post_init__(self) -> None: self.screeninfo = [(0, [])] self.cxy = self.pos2xy() self.lxy = (self.pos, 0) - self.calc_screen = self.calc_complete_screen + self.can_colorize = can_colorize() + + self.last_refresh_cache.screeninfo = self.screeninfo + self.last_refresh_cache.pos = self.pos + self.last_refresh_cache.cxy = self.cxy + self.last_refresh_cache.dimensions = (0, 0) def collect_keymap(self) -> tuple[tuple[KeySpec, CommandName], ...]: return default_keymap - def append_to_screen(self) -> list[str]: - new_screen = self.screen.copy() or [''] + def calc_screen(self) -> list[str]: + """Translate changes in self.buffer into changes in self.console.screen.""" + # Since the last call to calc_screen: + # screen and screeninfo may differ due to a completion menu being shown + # pos and cxy may differ due to edits, cursor movements, or completion menus - new_character = self.buffer[-1] - new_character_len = wlen(new_character) + # Lines that are above both the old and new cursor position can't have changed, + # unless the terminal has been resized (which might cause reflowing) or we've + # entered or left paste mode (which changes prompts, causing reflowing). + num_common_lines = 0 + offset = 0 + if self.last_refresh_cache.valid(self): + offset, num_common_lines = self.last_refresh_cache.get_cached_location(self) - last_line_len = wlen(new_screen[-1]) - if last_line_len + new_character_len >= self.console.width: # We need to wrap here - new_screen[-1] += '\\' - self.screeninfo[-1][1].append(1) - new_screen.append(self.buffer[-1]) - self.screeninfo.append((0, [new_character_len])) - else: - new_screen[-1] += self.buffer[-1] - self.screeninfo[-1][1].append(new_character_len) - self.cxy = self.pos2xy() + screen = self.last_refresh_cache.screen + del screen[num_common_lines:] - # Reset the function that is used for completing the screen - self.calc_screen = self.calc_complete_screen - return new_screen + screeninfo = self.last_refresh_cache.screeninfo + del screeninfo[num_common_lines:] + + last_refresh_line_end_offsets = self.last_refresh_cache.line_end_offsets + del last_refresh_line_end_offsets[num_common_lines:] - def calc_complete_screen(self) -> list[str]: - """The purpose of this method is to translate changes in - self.buffer into changes in self.screen. Currently it rips - everything down and starts from scratch, which whilst not - especially efficient is certainly simple(r). - """ - lines = self.get_unicode().split("\n") - screen: list[str] = [] - screeninfo: list[tuple[int, list[int]]] = [] pos = self.pos - for ln, line in enumerate(lines): + pos -= offset + + lines = "".join(self.buffer[offset:]).split("\n") + cursor_found = False + lines_beyond_cursor = 0 + for ln, line in enumerate(lines, num_common_lines): ll = len(line) if 0 <= pos <= ll: - if self.msg and not self.msg_at_bottom: - for mline in self.msg.split("\n"): - screen.append(mline) - screeninfo.append((0, [])) self.lxy = pos, ln + cursor_found = True + elif cursor_found: + lines_beyond_cursor += 1 + if lines_beyond_cursor > self.console.height: + # No need to keep formatting lines. + # The console can't show them. + break prompt = self.get_prompt(ln, ll >= pos >= 0) while "\n" in prompt: pre_prompt, _, prompt = prompt.partition("\n") + last_refresh_line_end_offsets.append(offset) screen.append(pre_prompt) screeninfo.append((0, [])) pos -= ll + 1 @@ -306,6 +360,8 @@ def calc_complete_screen(self) -> list[str]: l, l2 = disp_str(line) wrapcount = (wlen(l) + lp) // self.console.width if wrapcount == 0: + offset += ll + 1 # Takes all of the line plus the newline + last_refresh_line_end_offsets.append(offset) screen.append(prompt + l) screeninfo.append((lp, l2)) else: @@ -321,11 +377,14 @@ def calc_complete_screen(self) -> list[str]: column += character_width pre = prompt if i == 0 else "" if len(l) > index_to_wrap_before: + offset += index_to_wrap_before post = "\\" after = [1] else: + offset += index_to_wrap_before + 1 # Takes the newline post = "" after = [] + last_refresh_line_end_offsets.append(offset) screen.append(pre + l[:index_to_wrap_before] + post) screeninfo.append((prelen, l2[:index_to_wrap_before] + after)) l = l[index_to_wrap_before:] @@ -333,10 +392,12 @@ def calc_complete_screen(self) -> list[str]: i += 1 self.screeninfo = screeninfo self.cxy = self.pos2xy() - if self.msg and self.msg_at_bottom: + if self.msg: for mline in self.msg.split("\n"): screen.append(mline) screeninfo.append((0, [])) + + self.last_refresh_cache.update_cache(self, screen, screeninfo) return screen @staticmethod @@ -456,7 +517,7 @@ def get_prompt(self, lineno: int, cursor_on_line: bool) -> str: `lineno'.""" if self.arg is not None and cursor_on_line: prompt = f"(arg: {self.arg}) " - elif self.paste_mode: + elif self.paste_mode and not self.in_bracketed_paste: prompt = "(paste) " elif "\n" in self.buffer: if lineno == 0: @@ -468,7 +529,7 @@ def get_prompt(self, lineno: int, cursor_on_line: bool) -> str: else: prompt = self.ps1 - if can_colorize(): + if self.can_colorize: prompt = f"{ANSIColors.BOLD_MAGENTA}{prompt}{ANSIColors.RESET}" return prompt @@ -604,6 +665,9 @@ def update_screen(self) -> None: def refresh(self) -> None: """Recalculate and refresh the screen.""" + if self.in_bracketed_paste and self.buffer and not self.buffer[-1] == "\n": + return + # this call sets up self.cxy, so call it first. self.screen = self.calc_screen() self.console.refresh(self.screen, self.cxy) @@ -627,7 +691,7 @@ def do_cmd(self, cmd: tuple[str, list[str]]) -> None: self.after_command(command) - if self.dirty and not self.in_bracketed_paste: + if self.dirty: self.refresh() else: self.update_cursor() diff --git a/Lib/_pyrepl/readline.py b/Lib/_pyrepl/readline.py index 7d811bf41773fe..b10d0c66e4f813 100644 --- a/Lib/_pyrepl/readline.py +++ b/Lib/_pyrepl/readline.py @@ -263,6 +263,10 @@ def do(self) -> None: r = self.reader # type: ignore[assignment] r.dirty = True # this is needed to hide the completion menu, if visible + if self.reader.in_bracketed_paste: + r.insert("\n") + return + # if there are already several lines and the cursor # is not on the last one, always insert a new \n. text = r.get_unicode() diff --git a/Lib/_pyrepl/unix_console.py b/Lib/_pyrepl/unix_console.py index 2f73a59dd1fced..f1a6b84adfb671 100644 --- a/Lib/_pyrepl/unix_console.py +++ b/Lib/_pyrepl/unix_console.py @@ -150,6 +150,8 @@ def __init__( self.pollob = poll() self.pollob.register(self.input_fd, select.POLLIN) + self.input_buffer = b"" + self.input_buffer_pos = 0 curses.setupterm(term or None, self.output_fd) self.term = term @@ -197,6 +199,18 @@ def _my_getstr(cap: str, optional: bool = False) -> bytes | None: self.event_queue = EventQueue(self.input_fd, self.encoding) self.cursor_visible = 1 + def __read(self, n: int) -> bytes: + if not self.input_buffer or self.input_buffer_pos >= len(self.input_buffer): + self.input_buffer = os.read(self.input_fd, 10000) + + ret = self.input_buffer[self.input_buffer_pos : self.input_buffer_pos + n] + self.input_buffer_pos += len(ret) + if self.input_buffer_pos >= len(self.input_buffer): + self.input_buffer = b"" + self.input_buffer_pos = 0 + return ret + + def change_encoding(self, encoding: str) -> None: """ Change the encoding used for I/O operations. @@ -373,7 +387,7 @@ def get_event(self, block: bool = True) -> Event | None: while self.event_queue.empty(): while True: try: - self.push_char(os.read(self.input_fd, 1)) + self.push_char(self.__read(1)) except OSError as err: if err.errno == errno.EINTR: if not self.event_queue.empty(): @@ -491,7 +505,7 @@ def getpending(self): e.raw += e.raw amount = struct.unpack("i", ioctl(self.input_fd, FIONREAD, b"\0\0\0\0"))[0] - raw = os.read(self.input_fd, amount) + raw = self.__read(amount) data = str(raw, self.encoding, "replace") e.data += data e.raw += raw @@ -514,7 +528,7 @@ def getpending(self): e.raw += e.raw amount = 10000 - raw = os.read(self.input_fd, amount) + raw = self.__read(amount) data = str(raw, self.encoding, "replace") e.data += data e.raw += raw diff --git a/Lib/_pyrepl/utils.py b/Lib/_pyrepl/utils.py index 96e917e487d91a..20dbb1f7e17229 100644 --- a/Lib/_pyrepl/utils.py +++ b/Lib/_pyrepl/utils.py @@ -16,6 +16,8 @@ def str_width(c: str) -> int: def wlen(s: str) -> int: + if len(s) == 1: + return str_width(s) length = sum(str_width(i) for i in s) # remove lengths of any escape sequences sequence = ANSI_ESCAPE_SEQUENCE.findall(s)