diff options
Diffstat (limited to '')
-rw-r--r-- | src/prompt_toolkit/document.py | 1181 |
1 files changed, 1181 insertions, 0 deletions
diff --git a/src/prompt_toolkit/document.py b/src/prompt_toolkit/document.py new file mode 100644 index 0000000..74f4c13 --- /dev/null +++ b/src/prompt_toolkit/document.py @@ -0,0 +1,1181 @@ +""" +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, + ) |