Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/prompt_toolkit/lexers/base.py: 55%

1""" 

2Base classes for prompt_toolkit lexers. 

3""" 

4 

5from __future__ import annotations 

6 

7from abc import ABCMeta, abstractmethod 

8from typing import Callable, Hashable 

9 

10from prompt_toolkit.document import Document 

11from prompt_toolkit.formatted_text.base import StyleAndTextTuples 

12 

13__all__ = [ 

14 "Lexer", 

15 "SimpleLexer", 

16 "DynamicLexer", 

17] 

18 

19 

20class Lexer(metaclass=ABCMeta): 

21 """ 

22 Base class for all lexers. 

23 """ 

24 

25 @abstractmethod 

26 def lex_document(self, document: Document) -> Callable[[int], StyleAndTextTuples]: 

27 """ 

28 Takes a :class:`~prompt_toolkit.document.Document` and returns a 

29 callable that takes a line number and returns a list of 

30 ``(style_str, text)`` tuples for that line. 

31 

32 XXX: Note that in the past, this was supposed to return a list 

33 of ``(Token, text)`` tuples, just like a Pygments lexer. 

34 """ 

35 

36 def invalidation_hash(self) -> Hashable: 

37 """ 

38 When this changes, `lex_document` could give a different output. 

39 (Only used for `DynamicLexer`.) 

40 """ 

41 return id(self) 

42 

43 

44class SimpleLexer(Lexer): 

45 """ 

46 Lexer that doesn't do any tokenizing and returns the whole input as one 

47 token. 

48 

49 :param style: The style string for this lexer. 

50 """ 

51 

52 def __init__(self, style: str = "") -> None: 

53 self.style = style 

54 

55 def lex_document(self, document: Document) -> Callable[[int], StyleAndTextTuples]: 

56 lines = document.lines 

57 

58 def get_line(lineno: int) -> StyleAndTextTuples: 

59 "Return the tokens for the given line." 

60 try: 

61 return [(self.style, lines[lineno])] 

62 except IndexError: 

63 return [] 

64 

65 return get_line 

66 

67 

68class DynamicLexer(Lexer): 

69 """ 

70 Lexer class that can dynamically returns any Lexer. 

71 

72 :param get_lexer: Callable that returns a :class:`.Lexer` instance. 

73 """ 

74 

75 def __init__(self, get_lexer: Callable[[], Lexer | None]) -> None: 

76 self.get_lexer = get_lexer 

77 self._dummy = SimpleLexer() 

78 

79 def lex_document(self, document: Document) -> Callable[[int], StyleAndTextTuples]: 

80 lexer = self.get_lexer() or self._dummy 

81 return lexer.lex_document(document) 

82 

83 def invalidation_hash(self) -> Hashable: 

84 lexer = self.get_lexer() or self._dummy 

85 return id(lexer)