Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/pydantic/_internal/_docs_extraction.py: 23%

1"""Utilities related to attribute docstring extraction.""" 

2 

3from __future__ import annotations 

4 

5import ast 

6import inspect 

7import textwrap 

8from typing import Any 

9 

10 

11class DocstringVisitor(ast.NodeVisitor): 

12 def __init__(self) -> None: 

13 super().__init__() 

14 

15 self.target: str | None = None 

16 self.attrs: dict[str, str] = {} 

17 self.previous_node_type: type[ast.AST] | None = None 

18 

19 def visit(self, node: ast.AST) -> Any: 

20 node_result = super().visit(node) 

21 self.previous_node_type = type(node) 

22 return node_result 

23 

24 def visit_AnnAssign(self, node: ast.AnnAssign) -> Any: 

25 if isinstance(node.target, ast.Name): 

26 self.target = node.target.id 

27 

28 def visit_Expr(self, node: ast.Expr) -> Any: 

29 if ( 

30 isinstance(node.value, ast.Constant) 

31 and isinstance(node.value.value, str) 

32 and self.previous_node_type is ast.AnnAssign 

33 ): 

34 docstring = inspect.cleandoc(node.value.value) 

35 if self.target: 

36 self.attrs[self.target] = docstring 

37 self.target = None 

38 

39 

40def _dedent_source_lines(source: list[str]) -> str: 

41 # Required for nested class definitions, e.g. in a function block 

42 dedent_source = textwrap.dedent(''.join(source)) 

43 if dedent_source.startswith((' ', '\t')): 

44 # We are in the case where there's a dedented (usually multiline) string 

45 # at a lower indentation level than the class itself. We wrap our class 

46 # in a function as a workaround. 

47 dedent_source = f'def dedent_workaround():\n{dedent_source}' 

48 return dedent_source 

49 

50 

51def _extract_source_from_frame(cls: type[Any]) -> list[str] | None: 

52 frame = inspect.currentframe() 

53 

54 while frame: 

55 if inspect.getmodule(frame) is inspect.getmodule(cls): 

56 lnum = frame.f_lineno 

57 try: 

58 lines, _ = inspect.findsource(frame) 

59 except OSError: # pragma: no cover 

60 # Source can't be retrieved (maybe because running in an interactive terminal), 

61 # we don't want to error here. 

62 pass 

63 else: 

64 block_lines = inspect.getblock(lines[lnum - 1 :]) 

65 dedent_source = _dedent_source_lines(block_lines) 

66 try: 

67 block_tree = ast.parse(dedent_source) 

68 except SyntaxError: 

69 pass 

70 else: 

71 stmt = block_tree.body[0] 

72 if isinstance(stmt, ast.FunctionDef) and stmt.name == 'dedent_workaround': 

73 # `_dedent_source_lines` wrapped the class around the workaround function 

74 stmt = stmt.body[0] 

75 if isinstance(stmt, ast.ClassDef) and stmt.name == cls.__name__: 

76 return block_lines 

77 

78 frame = frame.f_back 

79 

80 

81def extract_docstrings_from_cls(cls: type[Any], use_inspect: bool = False) -> dict[str, str]: 

82 """Map model attributes and their corresponding docstring. 

83 

84 Args: 

85 cls: The class of the Pydantic model to inspect. 

86 use_inspect: Whether to skip usage of frames to find the object and use 

87 the `inspect` module instead. 

88 

89 Returns: 

90 A mapping containing attribute names and their corresponding docstring. 

91 """ 

92 if use_inspect: 

93 # Might not work as expected if two classes have the same name in the same source file. 

94 try: 

95 source, _ = inspect.getsourcelines(cls) 

96 except OSError: # pragma: no cover 

97 return {} 

98 else: 

99 source = _extract_source_from_frame(cls) 

100 

101 if not source: 

102 return {} 

103 

104 dedent_source = _dedent_source_lines(source) 

105 

106 visitor = DocstringVisitor() 

107 visitor.visit(ast.parse(dedent_source)) 

108 return visitor.attrs