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-rw-r--r--src/prompt_toolkit/document.py1181
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diff --git a/src/prompt_toolkit/document.py b/src/prompt_toolkit/document.py
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+"""
+The `Document` that implements all the text operations/querying.
+"""
+from __future__ import annotations
+
+import bisect
+import re
+import string
+import weakref
+from typing import Callable, Dict, Iterable, List, NoReturn, Pattern, cast
+
+from .clipboard import ClipboardData
+from .filters import vi_mode
+from .selection import PasteMode, SelectionState, SelectionType
+
+__all__ = [
+ "Document",
+]
+
+
+# Regex for finding "words" in documents. (We consider a group of alnum
+# characters a word, but also a group of special characters a word, as long as
+# it doesn't contain a space.)
+# (This is a 'word' in Vi.)
+_FIND_WORD_RE = re.compile(r"([a-zA-Z0-9_]+|[^a-zA-Z0-9_\s]+)")
+_FIND_CURRENT_WORD_RE = re.compile(r"^([a-zA-Z0-9_]+|[^a-zA-Z0-9_\s]+)")
+_FIND_CURRENT_WORD_INCLUDE_TRAILING_WHITESPACE_RE = re.compile(
+ r"^(([a-zA-Z0-9_]+|[^a-zA-Z0-9_\s]+)\s*)"
+)
+
+# Regex for finding "WORDS" in documents.
+# (This is a 'WORD in Vi.)
+_FIND_BIG_WORD_RE = re.compile(r"([^\s]+)")
+_FIND_CURRENT_BIG_WORD_RE = re.compile(r"^([^\s]+)")
+_FIND_CURRENT_BIG_WORD_INCLUDE_TRAILING_WHITESPACE_RE = re.compile(r"^([^\s]+\s*)")
+
+# Share the Document._cache between all Document instances.
+# (Document instances are considered immutable. That means that if another
+# `Document` is constructed with the same text, it should have the same
+# `_DocumentCache`.)
+_text_to_document_cache: dict[str, _DocumentCache] = cast(
+ Dict[str, "_DocumentCache"],
+ weakref.WeakValueDictionary(), # Maps document.text to DocumentCache instance.
+)
+
+
+class _ImmutableLineList(List[str]):
+ """
+ Some protection for our 'lines' list, which is assumed to be immutable in the cache.
+ (Useful for detecting obvious bugs.)
+ """
+
+ def _error(self, *a: object, **kw: object) -> NoReturn:
+ raise NotImplementedError("Attempt to modify an immutable list.")
+
+ __setitem__ = _error # type: ignore
+ append = _error
+ clear = _error
+ extend = _error
+ insert = _error
+ pop = _error
+ remove = _error
+ reverse = _error
+ sort = _error # type: ignore
+
+
+class _DocumentCache:
+ def __init__(self) -> None:
+ #: List of lines for the Document text.
+ self.lines: _ImmutableLineList | None = None
+
+ #: List of index positions, pointing to the start of all the lines.
+ self.line_indexes: list[int] | None = None
+
+
+class Document:
+ """
+ This is a immutable class around the text and cursor position, and contains
+ methods for querying this data, e.g. to give the text before the cursor.
+
+ This class is usually instantiated by a :class:`~prompt_toolkit.buffer.Buffer`
+ object, and accessed as the `document` property of that class.
+
+ :param text: string
+ :param cursor_position: int
+ :param selection: :class:`.SelectionState`
+ """
+
+ __slots__ = ("_text", "_cursor_position", "_selection", "_cache")
+
+ def __init__(
+ self,
+ text: str = "",
+ cursor_position: int | None = None,
+ selection: SelectionState | None = None,
+ ) -> None:
+ # Check cursor position. It can also be right after the end. (Where we
+ # insert text.)
+ assert cursor_position is None or cursor_position <= len(text), AssertionError(
+ f"cursor_position={cursor_position!r}, len_text={len(text)!r}"
+ )
+
+ # By default, if no cursor position was given, make sure to put the
+ # cursor position is at the end of the document. This is what makes
+ # sense in most places.
+ if cursor_position is None:
+ cursor_position = len(text)
+
+ # Keep these attributes private. A `Document` really has to be
+ # considered to be immutable, because otherwise the caching will break
+ # things. Because of that, we wrap these into read-only properties.
+ self._text = text
+ self._cursor_position = cursor_position
+ self._selection = selection
+
+ # Cache for lines/indexes. (Shared with other Document instances that
+ # contain the same text.
+ try:
+ self._cache = _text_to_document_cache[self.text]
+ except KeyError:
+ self._cache = _DocumentCache()
+ _text_to_document_cache[self.text] = self._cache
+
+ # XX: For some reason, above, we can't use 'WeakValueDictionary.setdefault'.
+ # This fails in Pypy3. `self._cache` becomes None, because that's what
+ # 'setdefault' returns.
+ # self._cache = _text_to_document_cache.setdefault(self.text, _DocumentCache())
+ # assert self._cache
+
+ def __repr__(self) -> str:
+ return f"{self.__class__.__name__}({self.text!r}, {self.cursor_position!r})"
+
+ def __eq__(self, other: object) -> bool:
+ if not isinstance(other, Document):
+ return False
+
+ return (
+ self.text == other.text
+ and self.cursor_position == other.cursor_position
+ and self.selection == other.selection
+ )
+
+ @property
+ def text(self) -> str:
+ "The document text."
+ return self._text
+
+ @property
+ def cursor_position(self) -> int:
+ "The document cursor position."
+ return self._cursor_position
+
+ @property
+ def selection(self) -> SelectionState | None:
+ ":class:`.SelectionState` object."
+ return self._selection
+
+ @property
+ def current_char(self) -> str:
+ """Return character under cursor or an empty string."""
+ return self._get_char_relative_to_cursor(0) or ""
+
+ @property
+ def char_before_cursor(self) -> str:
+ """Return character before the cursor or an empty string."""
+ return self._get_char_relative_to_cursor(-1) or ""
+
+ @property
+ def text_before_cursor(self) -> str:
+ return self.text[: self.cursor_position :]
+
+ @property
+ def text_after_cursor(self) -> str:
+ return self.text[self.cursor_position :]
+
+ @property
+ def current_line_before_cursor(self) -> str:
+ """Text from the start of the line until the cursor."""
+ _, _, text = self.text_before_cursor.rpartition("\n")
+ return text
+
+ @property
+ def current_line_after_cursor(self) -> str:
+ """Text from the cursor until the end of the line."""
+ text, _, _ = self.text_after_cursor.partition("\n")
+ return text
+
+ @property
+ def lines(self) -> list[str]:
+ """
+ Array of all the lines.
+ """
+ # Cache, because this one is reused very often.
+ if self._cache.lines is None:
+ self._cache.lines = _ImmutableLineList(self.text.split("\n"))
+
+ return self._cache.lines
+
+ @property
+ def _line_start_indexes(self) -> list[int]:
+ """
+ Array pointing to the start indexes of all the lines.
+ """
+ # Cache, because this is often reused. (If it is used, it's often used
+ # many times. And this has to be fast for editing big documents!)
+ if self._cache.line_indexes is None:
+ # Create list of line lengths.
+ line_lengths = map(len, self.lines)
+
+ # Calculate cumulative sums.
+ indexes = [0]
+ append = indexes.append
+ pos = 0
+
+ for line_length in line_lengths:
+ pos += line_length + 1
+ append(pos)
+
+ # Remove the last item. (This is not a new line.)
+ if len(indexes) > 1:
+ indexes.pop()
+
+ self._cache.line_indexes = indexes
+
+ return self._cache.line_indexes
+
+ @property
+ def lines_from_current(self) -> list[str]:
+ """
+ Array of the lines starting from the current line, until the last line.
+ """
+ return self.lines[self.cursor_position_row :]
+
+ @property
+ def line_count(self) -> int:
+ r"""Return the number of lines in this document. If the document ends
+ with a trailing \n, that counts as the beginning of a new line."""
+ return len(self.lines)
+
+ @property
+ def current_line(self) -> str:
+ """Return the text on the line where the cursor is. (when the input
+ consists of just one line, it equals `text`."""
+ return self.current_line_before_cursor + self.current_line_after_cursor
+
+ @property
+ def leading_whitespace_in_current_line(self) -> str:
+ """The leading whitespace in the left margin of the current line."""
+ current_line = self.current_line
+ length = len(current_line) - len(current_line.lstrip())
+ return current_line[:length]
+
+ def _get_char_relative_to_cursor(self, offset: int = 0) -> str:
+ """
+ Return character relative to cursor position, or empty string
+ """
+ try:
+ return self.text[self.cursor_position + offset]
+ except IndexError:
+ return ""
+
+ @property
+ def on_first_line(self) -> bool:
+ """
+ True when we are at the first line.
+ """
+ return self.cursor_position_row == 0
+
+ @property
+ def on_last_line(self) -> bool:
+ """
+ True when we are at the last line.
+ """
+ return self.cursor_position_row == self.line_count - 1
+
+ @property
+ def cursor_position_row(self) -> int:
+ """
+ Current row. (0-based.)
+ """
+ row, _ = self._find_line_start_index(self.cursor_position)
+ return row
+
+ @property
+ def cursor_position_col(self) -> int:
+ """
+ Current column. (0-based.)
+ """
+ # (Don't use self.text_before_cursor to calculate this. Creating
+ # substrings and doing rsplit is too expensive for getting the cursor
+ # position.)
+ _, line_start_index = self._find_line_start_index(self.cursor_position)
+ return self.cursor_position - line_start_index
+
+ def _find_line_start_index(self, index: int) -> tuple[int, int]:
+ """
+ For the index of a character at a certain line, calculate the index of
+ the first character on that line.
+
+ Return (row, index) tuple.
+ """
+ indexes = self._line_start_indexes
+
+ pos = bisect.bisect_right(indexes, index) - 1
+ return pos, indexes[pos]
+
+ def translate_index_to_position(self, index: int) -> tuple[int, int]:
+ """
+ Given an index for the text, return the corresponding (row, col) tuple.
+ (0-based. Returns (0, 0) for index=0.)
+ """
+ # Find start of this line.
+ row, row_index = self._find_line_start_index(index)
+ col = index - row_index
+
+ return row, col
+
+ def translate_row_col_to_index(self, row: int, col: int) -> int:
+ """
+ Given a (row, col) tuple, return the corresponding index.
+ (Row and col params are 0-based.)
+
+ Negative row/col values are turned into zero.
+ """
+ try:
+ result = self._line_start_indexes[row]
+ line = self.lines[row]
+ except IndexError:
+ if row < 0:
+ result = self._line_start_indexes[0]
+ line = self.lines[0]
+ else:
+ result = self._line_start_indexes[-1]
+ line = self.lines[-1]
+
+ result += max(0, min(col, len(line)))
+
+ # Keep in range. (len(self.text) is included, because the cursor can be
+ # right after the end of the text as well.)
+ result = max(0, min(result, len(self.text)))
+ return result
+
+ @property
+ def is_cursor_at_the_end(self) -> bool:
+ """True when the cursor is at the end of the text."""
+ return self.cursor_position == len(self.text)
+
+ @property
+ def is_cursor_at_the_end_of_line(self) -> bool:
+ """True when the cursor is at the end of this line."""
+ return self.current_char in ("\n", "")
+
+ def has_match_at_current_position(self, sub: str) -> bool:
+ """
+ `True` when this substring is found at the cursor position.
+ """
+ return self.text.find(sub, self.cursor_position) == self.cursor_position
+
+ def find(
+ self,
+ sub: str,
+ in_current_line: bool = False,
+ include_current_position: bool = False,
+ ignore_case: bool = False,
+ count: int = 1,
+ ) -> int | None:
+ """
+ Find `text` after the cursor, return position relative to the cursor
+ position. Return `None` if nothing was found.
+
+ :param count: Find the n-th occurrence.
+ """
+ assert isinstance(ignore_case, bool)
+
+ if in_current_line:
+ text = self.current_line_after_cursor
+ else:
+ text = self.text_after_cursor
+
+ if not include_current_position:
+ if len(text) == 0:
+ return None # (Otherwise, we always get a match for the empty string.)
+ else:
+ text = text[1:]
+
+ flags = re.IGNORECASE if ignore_case else 0
+ iterator = re.finditer(re.escape(sub), text, flags)
+
+ try:
+ for i, match in enumerate(iterator):
+ if i + 1 == count:
+ if include_current_position:
+ return match.start(0)
+ else:
+ return match.start(0) + 1
+ except StopIteration:
+ pass
+ return None
+
+ def find_all(self, sub: str, ignore_case: bool = False) -> list[int]:
+ """
+ Find all occurrences of the substring. Return a list of absolute
+ positions in the document.
+ """
+ flags = re.IGNORECASE if ignore_case else 0
+ return [a.start() for a in re.finditer(re.escape(sub), self.text, flags)]
+
+ def find_backwards(
+ self,
+ sub: str,
+ in_current_line: bool = False,
+ ignore_case: bool = False,
+ count: int = 1,
+ ) -> int | None:
+ """
+ Find `text` before the cursor, return position relative to the cursor
+ position. Return `None` if nothing was found.
+
+ :param count: Find the n-th occurrence.
+ """
+ if in_current_line:
+ before_cursor = self.current_line_before_cursor[::-1]
+ else:
+ before_cursor = self.text_before_cursor[::-1]
+
+ flags = re.IGNORECASE if ignore_case else 0
+ iterator = re.finditer(re.escape(sub[::-1]), before_cursor, flags)
+
+ try:
+ for i, match in enumerate(iterator):
+ if i + 1 == count:
+ return -match.start(0) - len(sub)
+ except StopIteration:
+ pass
+ return None
+
+ def get_word_before_cursor(
+ self, WORD: bool = False, pattern: Pattern[str] | None = None
+ ) -> str:
+ """
+ Give the word before the cursor.
+ If we have whitespace before the cursor this returns an empty string.
+
+ :param pattern: (None or compiled regex). When given, use this regex
+ pattern.
+ """
+ if self._is_word_before_cursor_complete(WORD=WORD, pattern=pattern):
+ # Space before the cursor or no text before cursor.
+ return ""
+
+ text_before_cursor = self.text_before_cursor
+ start = self.find_start_of_previous_word(WORD=WORD, pattern=pattern) or 0
+
+ return text_before_cursor[len(text_before_cursor) + start :]
+
+ def _is_word_before_cursor_complete(
+ self, WORD: bool = False, pattern: Pattern[str] | None = None
+ ) -> bool:
+ if pattern:
+ return self.find_start_of_previous_word(WORD=WORD, pattern=pattern) is None
+ else:
+ return (
+ self.text_before_cursor == "" or self.text_before_cursor[-1:].isspace()
+ )
+
+ def find_start_of_previous_word(
+ self, count: int = 1, WORD: bool = False, pattern: Pattern[str] | None = None
+ ) -> int | None:
+ """
+ Return an index relative to the cursor position pointing to the start
+ of the previous word. Return `None` if nothing was found.
+
+ :param pattern: (None or compiled regex). When given, use this regex
+ pattern.
+ """
+ assert not (WORD and pattern)
+
+ # Reverse the text before the cursor, in order to do an efficient
+ # backwards search.
+ text_before_cursor = self.text_before_cursor[::-1]
+
+ if pattern:
+ regex = pattern
+ elif WORD:
+ regex = _FIND_BIG_WORD_RE
+ else:
+ regex = _FIND_WORD_RE
+
+ iterator = regex.finditer(text_before_cursor)
+
+ try:
+ for i, match in enumerate(iterator):
+ if i + 1 == count:
+ return -match.end(0)
+ except StopIteration:
+ pass
+ return None
+
+ def find_boundaries_of_current_word(
+ self,
+ WORD: bool = False,
+ include_leading_whitespace: bool = False,
+ include_trailing_whitespace: bool = False,
+ ) -> tuple[int, int]:
+ """
+ Return the relative boundaries (startpos, endpos) of the current word under the
+ cursor. (This is at the current line, because line boundaries obviously
+ don't belong to any word.)
+ If not on a word, this returns (0,0)
+ """
+ text_before_cursor = self.current_line_before_cursor[::-1]
+ text_after_cursor = self.current_line_after_cursor
+
+ def get_regex(include_whitespace: bool) -> Pattern[str]:
+ return {
+ (False, False): _FIND_CURRENT_WORD_RE,
+ (False, True): _FIND_CURRENT_WORD_INCLUDE_TRAILING_WHITESPACE_RE,
+ (True, False): _FIND_CURRENT_BIG_WORD_RE,
+ (True, True): _FIND_CURRENT_BIG_WORD_INCLUDE_TRAILING_WHITESPACE_RE,
+ }[(WORD, include_whitespace)]
+
+ match_before = get_regex(include_leading_whitespace).search(text_before_cursor)
+ match_after = get_regex(include_trailing_whitespace).search(text_after_cursor)
+
+ # When there is a match before and after, and we're not looking for
+ # WORDs, make sure that both the part before and after the cursor are
+ # either in the [a-zA-Z_] alphabet or not. Otherwise, drop the part
+ # before the cursor.
+ if not WORD and match_before and match_after:
+ c1 = self.text[self.cursor_position - 1]
+ c2 = self.text[self.cursor_position]
+ alphabet = string.ascii_letters + "0123456789_"
+
+ if (c1 in alphabet) != (c2 in alphabet):
+ match_before = None
+
+ return (
+ -match_before.end(1) if match_before else 0,
+ match_after.end(1) if match_after else 0,
+ )
+
+ def get_word_under_cursor(self, WORD: bool = False) -> str:
+ """
+ Return the word, currently below the cursor.
+ This returns an empty string when the cursor is on a whitespace region.
+ """
+ start, end = self.find_boundaries_of_current_word(WORD=WORD)
+ return self.text[self.cursor_position + start : self.cursor_position + end]
+
+ def find_next_word_beginning(
+ self, count: int = 1, WORD: bool = False
+ ) -> int | None:
+ """
+ Return an index relative to the cursor position pointing to the start
+ of the next word. Return `None` if nothing was found.
+ """
+ if count < 0:
+ return self.find_previous_word_beginning(count=-count, WORD=WORD)
+
+ regex = _FIND_BIG_WORD_RE if WORD else _FIND_WORD_RE
+ iterator = regex.finditer(self.text_after_cursor)
+
+ try:
+ for i, match in enumerate(iterator):
+ # Take first match, unless it's the word on which we're right now.
+ if i == 0 and match.start(1) == 0:
+ count += 1
+
+ if i + 1 == count:
+ return match.start(1)
+ except StopIteration:
+ pass
+ return None
+
+ def find_next_word_ending(
+ self, include_current_position: bool = False, count: int = 1, WORD: bool = False
+ ) -> int | None:
+ """
+ Return an index relative to the cursor position pointing to the end
+ of the next word. Return `None` if nothing was found.
+ """
+ if count < 0:
+ return self.find_previous_word_ending(count=-count, WORD=WORD)
+
+ if include_current_position:
+ text = self.text_after_cursor
+ else:
+ text = self.text_after_cursor[1:]
+
+ regex = _FIND_BIG_WORD_RE if WORD else _FIND_WORD_RE
+ iterable = regex.finditer(text)
+
+ try:
+ for i, match in enumerate(iterable):
+ if i + 1 == count:
+ value = match.end(1)
+
+ if include_current_position:
+ return value
+ else:
+ return value + 1
+
+ except StopIteration:
+ pass
+ return None
+
+ def find_previous_word_beginning(
+ self, count: int = 1, WORD: bool = False
+ ) -> int | None:
+ """
+ Return an index relative to the cursor position pointing to the start
+ of the previous word. Return `None` if nothing was found.
+ """
+ if count < 0:
+ return self.find_next_word_beginning(count=-count, WORD=WORD)
+
+ regex = _FIND_BIG_WORD_RE if WORD else _FIND_WORD_RE
+ iterator = regex.finditer(self.text_before_cursor[::-1])
+
+ try:
+ for i, match in enumerate(iterator):
+ if i + 1 == count:
+ return -match.end(1)
+ except StopIteration:
+ pass
+ return None
+
+ def find_previous_word_ending(
+ self, count: int = 1, WORD: bool = False
+ ) -> int | None:
+ """
+ Return an index relative to the cursor position pointing to the end
+ of the previous word. Return `None` if nothing was found.
+ """
+ if count < 0:
+ return self.find_next_word_ending(count=-count, WORD=WORD)
+
+ text_before_cursor = self.text_after_cursor[:1] + self.text_before_cursor[::-1]
+
+ regex = _FIND_BIG_WORD_RE if WORD else _FIND_WORD_RE
+ iterator = regex.finditer(text_before_cursor)
+
+ try:
+ for i, match in enumerate(iterator):
+ # Take first match, unless it's the word on which we're right now.
+ if i == 0 and match.start(1) == 0:
+ count += 1
+
+ if i + 1 == count:
+ return -match.start(1) + 1
+ except StopIteration:
+ pass
+ return None
+
+ def find_next_matching_line(
+ self, match_func: Callable[[str], bool], count: int = 1
+ ) -> int | None:
+ """
+ Look downwards for empty lines.
+ Return the line index, relative to the current line.
+ """
+ result = None
+
+ for index, line in enumerate(self.lines[self.cursor_position_row + 1 :]):
+ if match_func(line):
+ result = 1 + index
+ count -= 1
+
+ if count == 0:
+ break
+
+ return result
+
+ def find_previous_matching_line(
+ self, match_func: Callable[[str], bool], count: int = 1
+ ) -> int | None:
+ """
+ Look upwards for empty lines.
+ Return the line index, relative to the current line.
+ """
+ result = None
+
+ for index, line in enumerate(self.lines[: self.cursor_position_row][::-1]):
+ if match_func(line):
+ result = -1 - index
+ count -= 1
+
+ if count == 0:
+ break
+
+ return result
+
+ def get_cursor_left_position(self, count: int = 1) -> int:
+ """
+ Relative position for cursor left.
+ """
+ if count < 0:
+ return self.get_cursor_right_position(-count)
+
+ return -min(self.cursor_position_col, count)
+
+ def get_cursor_right_position(self, count: int = 1) -> int:
+ """
+ Relative position for cursor_right.
+ """
+ if count < 0:
+ return self.get_cursor_left_position(-count)
+
+ return min(count, len(self.current_line_after_cursor))
+
+ def get_cursor_up_position(
+ self, count: int = 1, preferred_column: int | None = None
+ ) -> int:
+ """
+ Return the relative cursor position (character index) where we would be if the
+ user pressed the arrow-up button.
+
+ :param preferred_column: When given, go to this column instead of
+ staying at the current column.
+ """
+ assert count >= 1
+ column = (
+ self.cursor_position_col if preferred_column is None else preferred_column
+ )
+
+ return (
+ self.translate_row_col_to_index(
+ max(0, self.cursor_position_row - count), column
+ )
+ - self.cursor_position
+ )
+
+ def get_cursor_down_position(
+ self, count: int = 1, preferred_column: int | None = None
+ ) -> int:
+ """
+ Return the relative cursor position (character index) where we would be if the
+ user pressed the arrow-down button.
+
+ :param preferred_column: When given, go to this column instead of
+ staying at the current column.
+ """
+ assert count >= 1
+ column = (
+ self.cursor_position_col if preferred_column is None else preferred_column
+ )
+
+ return (
+ self.translate_row_col_to_index(self.cursor_position_row + count, column)
+ - self.cursor_position
+ )
+
+ def find_enclosing_bracket_right(
+ self, left_ch: str, right_ch: str, end_pos: int | None = None
+ ) -> int | None:
+ """
+ Find the right bracket enclosing current position. Return the relative
+ position to the cursor position.
+
+ When `end_pos` is given, don't look past the position.
+ """
+ if self.current_char == right_ch:
+ return 0
+
+ if end_pos is None:
+ end_pos = len(self.text)
+ else:
+ end_pos = min(len(self.text), end_pos)
+
+ stack = 1
+
+ # Look forward.
+ for i in range(self.cursor_position + 1, end_pos):
+ c = self.text[i]
+
+ if c == left_ch:
+ stack += 1
+ elif c == right_ch:
+ stack -= 1
+
+ if stack == 0:
+ return i - self.cursor_position
+
+ return None
+
+ def find_enclosing_bracket_left(
+ self, left_ch: str, right_ch: str, start_pos: int | None = None
+ ) -> int | None:
+ """
+ Find the left bracket enclosing current position. Return the relative
+ position to the cursor position.
+
+ When `start_pos` is given, don't look past the position.
+ """
+ if self.current_char == left_ch:
+ return 0
+
+ if start_pos is None:
+ start_pos = 0
+ else:
+ start_pos = max(0, start_pos)
+
+ stack = 1
+
+ # Look backward.
+ for i in range(self.cursor_position - 1, start_pos - 1, -1):
+ c = self.text[i]
+
+ if c == right_ch:
+ stack += 1
+ elif c == left_ch:
+ stack -= 1
+
+ if stack == 0:
+ return i - self.cursor_position
+
+ return None
+
+ def find_matching_bracket_position(
+ self, start_pos: int | None = None, end_pos: int | None = None
+ ) -> int:
+ """
+ Return relative cursor position of matching [, (, { or < bracket.
+
+ When `start_pos` or `end_pos` are given. Don't look past the positions.
+ """
+
+ # Look for a match.
+ for pair in "()", "[]", "{}", "<>":
+ A = pair[0]
+ B = pair[1]
+ if self.current_char == A:
+ return self.find_enclosing_bracket_right(A, B, end_pos=end_pos) or 0
+ elif self.current_char == B:
+ return self.find_enclosing_bracket_left(A, B, start_pos=start_pos) or 0
+
+ return 0
+
+ def get_start_of_document_position(self) -> int:
+ """Relative position for the start of the document."""
+ return -self.cursor_position
+
+ def get_end_of_document_position(self) -> int:
+ """Relative position for the end of the document."""
+ return len(self.text) - self.cursor_position
+
+ def get_start_of_line_position(self, after_whitespace: bool = False) -> int:
+ """Relative position for the start of this line."""
+ if after_whitespace:
+ current_line = self.current_line
+ return (
+ len(current_line)
+ - len(current_line.lstrip())
+ - self.cursor_position_col
+ )
+ else:
+ return -len(self.current_line_before_cursor)
+
+ def get_end_of_line_position(self) -> int:
+ """Relative position for the end of this line."""
+ return len(self.current_line_after_cursor)
+
+ def last_non_blank_of_current_line_position(self) -> int:
+ """
+ Relative position for the last non blank character of this line.
+ """
+ return len(self.current_line.rstrip()) - self.cursor_position_col - 1
+
+ def get_column_cursor_position(self, column: int) -> int:
+ """
+ Return the relative cursor position for this column at the current
+ line. (It will stay between the boundaries of the line in case of a
+ larger number.)
+ """
+ line_length = len(self.current_line)
+ current_column = self.cursor_position_col
+ column = max(0, min(line_length, column))
+
+ return column - current_column
+
+ def selection_range(
+ self,
+ ) -> tuple[
+ int, int
+ ]: # XXX: shouldn't this return `None` if there is no selection???
+ """
+ Return (from, to) tuple of the selection.
+ start and end position are included.
+
+ This doesn't take the selection type into account. Use
+ `selection_ranges` instead.
+ """
+ if self.selection:
+ from_, to = sorted(
+ [self.cursor_position, self.selection.original_cursor_position]
+ )
+ else:
+ from_, to = self.cursor_position, self.cursor_position
+
+ return from_, to
+
+ def selection_ranges(self) -> Iterable[tuple[int, int]]:
+ """
+ Return a list of `(from, to)` tuples for the selection or none if
+ nothing was selected. The upper boundary is not included.
+
+ This will yield several (from, to) tuples in case of a BLOCK selection.
+ This will return zero ranges, like (8,8) for empty lines in a block
+ selection.
+ """
+ if self.selection:
+ from_, to = sorted(
+ [self.cursor_position, self.selection.original_cursor_position]
+ )
+
+ if self.selection.type == SelectionType.BLOCK:
+ from_line, from_column = self.translate_index_to_position(from_)
+ to_line, to_column = self.translate_index_to_position(to)
+ from_column, to_column = sorted([from_column, to_column])
+ lines = self.lines
+
+ if vi_mode():
+ to_column += 1
+
+ for l in range(from_line, to_line + 1):
+ line_length = len(lines[l])
+
+ if from_column <= line_length:
+ yield (
+ self.translate_row_col_to_index(l, from_column),
+ self.translate_row_col_to_index(
+ l, min(line_length, to_column)
+ ),
+ )
+ else:
+ # In case of a LINES selection, go to the start/end of the lines.
+ if self.selection.type == SelectionType.LINES:
+ from_ = max(0, self.text.rfind("\n", 0, from_) + 1)
+
+ if self.text.find("\n", to) >= 0:
+ to = self.text.find("\n", to)
+ else:
+ to = len(self.text) - 1
+
+ # In Vi mode, the upper boundary is always included. For Emacs,
+ # that's not the case.
+ if vi_mode():
+ to += 1
+
+ yield from_, to
+
+ def selection_range_at_line(self, row: int) -> tuple[int, int] | None:
+ """
+ If the selection spans a portion of the given line, return a (from, to) tuple.
+
+ The returned upper boundary is not included in the selection, so
+ `(0, 0)` is an empty selection. `(0, 1)`, is a one character selection.
+
+ Returns None if the selection doesn't cover this line at all.
+ """
+ if self.selection:
+ line = self.lines[row]
+
+ row_start = self.translate_row_col_to_index(row, 0)
+ row_end = self.translate_row_col_to_index(row, len(line))
+
+ from_, to = sorted(
+ [self.cursor_position, self.selection.original_cursor_position]
+ )
+
+ # Take the intersection of the current line and the selection.
+ intersection_start = max(row_start, from_)
+ intersection_end = min(row_end, to)
+
+ if intersection_start <= intersection_end:
+ if self.selection.type == SelectionType.LINES:
+ intersection_start = row_start
+ intersection_end = row_end
+
+ elif self.selection.type == SelectionType.BLOCK:
+ _, col1 = self.translate_index_to_position(from_)
+ _, col2 = self.translate_index_to_position(to)
+ col1, col2 = sorted([col1, col2])
+
+ if col1 > len(line):
+ return None # Block selection doesn't cross this line.
+
+ intersection_start = self.translate_row_col_to_index(row, col1)
+ intersection_end = self.translate_row_col_to_index(row, col2)
+
+ _, from_column = self.translate_index_to_position(intersection_start)
+ _, to_column = self.translate_index_to_position(intersection_end)
+
+ # In Vi mode, the upper boundary is always included. For Emacs
+ # mode, that's not the case.
+ if vi_mode():
+ to_column += 1
+
+ return from_column, to_column
+ return None
+
+ def cut_selection(self) -> tuple[Document, ClipboardData]:
+ """
+ Return a (:class:`.Document`, :class:`.ClipboardData`) tuple, where the
+ document represents the new document when the selection is cut, and the
+ clipboard data, represents whatever has to be put on the clipboard.
+ """
+ if self.selection:
+ cut_parts = []
+ remaining_parts = []
+ new_cursor_position = self.cursor_position
+
+ last_to = 0
+ for from_, to in self.selection_ranges():
+ if last_to == 0:
+ new_cursor_position = from_
+
+ remaining_parts.append(self.text[last_to:from_])
+ cut_parts.append(self.text[from_:to])
+ last_to = to
+
+ remaining_parts.append(self.text[last_to:])
+
+ cut_text = "\n".join(cut_parts)
+ remaining_text = "".join(remaining_parts)
+
+ # In case of a LINES selection, don't include the trailing newline.
+ if self.selection.type == SelectionType.LINES and cut_text.endswith("\n"):
+ cut_text = cut_text[:-1]
+
+ return (
+ Document(text=remaining_text, cursor_position=new_cursor_position),
+ ClipboardData(cut_text, self.selection.type),
+ )
+ else:
+ return self, ClipboardData("")
+
+ def paste_clipboard_data(
+ self,
+ data: ClipboardData,
+ paste_mode: PasteMode = PasteMode.EMACS,
+ count: int = 1,
+ ) -> Document:
+ """
+ Return a new :class:`.Document` instance which contains the result if
+ we would paste this data at the current cursor position.
+
+ :param paste_mode: Where to paste. (Before/after/emacs.)
+ :param count: When >1, Paste multiple times.
+ """
+ before = paste_mode == PasteMode.VI_BEFORE
+ after = paste_mode == PasteMode.VI_AFTER
+
+ if data.type == SelectionType.CHARACTERS:
+ if after:
+ new_text = (
+ self.text[: self.cursor_position + 1]
+ + data.text * count
+ + self.text[self.cursor_position + 1 :]
+ )
+ else:
+ new_text = (
+ self.text_before_cursor + data.text * count + self.text_after_cursor
+ )
+
+ new_cursor_position = self.cursor_position + len(data.text) * count
+ if before:
+ new_cursor_position -= 1
+
+ elif data.type == SelectionType.LINES:
+ l = self.cursor_position_row
+ if before:
+ lines = self.lines[:l] + [data.text] * count + self.lines[l:]
+ new_text = "\n".join(lines)
+ new_cursor_position = len("".join(self.lines[:l])) + l
+ else:
+ lines = self.lines[: l + 1] + [data.text] * count + self.lines[l + 1 :]
+ new_cursor_position = len("".join(self.lines[: l + 1])) + l + 1
+ new_text = "\n".join(lines)
+
+ elif data.type == SelectionType.BLOCK:
+ lines = self.lines[:]
+ start_line = self.cursor_position_row
+ start_column = self.cursor_position_col + (0 if before else 1)
+
+ for i, line in enumerate(data.text.split("\n")):
+ index = i + start_line
+ if index >= len(lines):
+ lines.append("")
+
+ lines[index] = lines[index].ljust(start_column)
+ lines[index] = (
+ lines[index][:start_column]
+ + line * count
+ + lines[index][start_column:]
+ )
+
+ new_text = "\n".join(lines)
+ new_cursor_position = self.cursor_position + (0 if before else 1)
+
+ return Document(text=new_text, cursor_position=new_cursor_position)
+
+ def empty_line_count_at_the_end(self) -> int:
+ """
+ Return number of empty lines at the end of the document.
+ """
+ count = 0
+ for line in self.lines[::-1]:
+ if not line or line.isspace():
+ count += 1
+ else:
+ break
+
+ return count
+
+ def start_of_paragraph(self, count: int = 1, before: bool = False) -> int:
+ """
+ Return the start of the current paragraph. (Relative cursor position.)
+ """
+
+ def match_func(text: str) -> bool:
+ return not text or text.isspace()
+
+ line_index = self.find_previous_matching_line(
+ match_func=match_func, count=count
+ )
+
+ if line_index:
+ add = 0 if before else 1
+ return min(0, self.get_cursor_up_position(count=-line_index) + add)
+ else:
+ return -self.cursor_position
+
+ def end_of_paragraph(self, count: int = 1, after: bool = False) -> int:
+ """
+ Return the end of the current paragraph. (Relative cursor position.)
+ """
+
+ def match_func(text: str) -> bool:
+ return not text or text.isspace()
+
+ line_index = self.find_next_matching_line(match_func=match_func, count=count)
+
+ if line_index:
+ add = 0 if after else 1
+ return max(0, self.get_cursor_down_position(count=line_index) - add)
+ else:
+ return len(self.text_after_cursor)
+
+ # Modifiers.
+
+ def insert_after(self, text: str) -> Document:
+ """
+ Create a new document, with this text inserted after the buffer.
+ It keeps selection ranges and cursor position in sync.
+ """
+ return Document(
+ text=self.text + text,
+ cursor_position=self.cursor_position,
+ selection=self.selection,
+ )
+
+ def insert_before(self, text: str) -> Document:
+ """
+ Create a new document, with this text inserted before the buffer.
+ It keeps selection ranges and cursor position in sync.
+ """
+ selection_state = self.selection
+
+ if selection_state:
+ selection_state = SelectionState(
+ original_cursor_position=selection_state.original_cursor_position
+ + len(text),
+ type=selection_state.type,
+ )
+
+ return Document(
+ text=text + self.text,
+ cursor_position=self.cursor_position + len(text),
+ selection=selection_state,
+ )