""" The `Document` that implements all the text operations/querying. """ import bisect import re import string import weakref from typing import Callable, Dict, Iterable, List, Optional, Pattern, Tuple, 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): """ 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) -> None: 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: Optional[_ImmutableLineList] = None #: List of index positions, pointing to the start of all the lines. self.line_indexes: Optional[List[int]] = 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: Optional[int] = None, selection: Optional[SelectionState] = 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( "cursor_position=%r, len_text=%r" % (cursor_position, len(text)) ) # 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 "%s(%r, %r)" % (self.__class__.__name__, self.text, self.cursor_position) 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) -> Optional[SelectionState]: " :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, ) -> Optional[int]: """ 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, ) -> Optional[int]: """ 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: Optional[Pattern[str]] = 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: Optional[Pattern[str]] = 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: Optional[Pattern[str]] = None ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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 ) -> Optional[int]: """ 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: Optional[int] = 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: Optional[int] = 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: Optional[int] = None ) -> Optional[int]: """ 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: Optional[int] = None ) -> Optional[int]: """ 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: Optional[int] = None, end_pos: Optional[int] = 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) -> Optional[Tuple[int, int]]: """ 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, )