Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/astroid/brain/brain_hypothesis.py: 53%

1# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html 

2# For details: https://github.com/pylint-dev/astroid/blob/main/LICENSE 

3# Copyright (c) https://github.com/pylint-dev/astroid/blob/main/CONTRIBUTORS.txt 

4 

5""" 

6Astroid hook for the Hypothesis library. 

7 

8Without this hook pylint reports no-value-for-parameter for use of strategies 

9defined using the `@hypothesis.strategies.composite` decorator. For example: 

10 

11 from hypothesis import strategies as st 

12 

13 @st.composite 

14 def a_strategy(draw): 

15 return draw(st.integers()) 

16 

17 a_strategy() 

18""" 

19 

20from astroid.manager import AstroidManager 

21from astroid.nodes.scoped_nodes import FunctionDef 

22 

23COMPOSITE_NAMES = ( 

24 "composite", 

25 "st.composite", 

26 "strategies.composite", 

27 "hypothesis.strategies.composite", 

28) 

29 

30 

31def is_decorated_with_st_composite(node: FunctionDef) -> bool: 

32 """Return whether a decorated node has @st.composite applied.""" 

33 if node.decorators and node.args.args and node.args.args[0].name == "draw": 

34 for decorator_attribute in node.decorators.nodes: 

35 if decorator_attribute.as_string() in COMPOSITE_NAMES: 

36 return True 

37 return False 

38 

39 

40def remove_draw_parameter_from_composite_strategy(node: FunctionDef) -> FunctionDef: 

41 """Given that the FunctionDef is decorated with @st.composite, remove the 

42 first argument (`draw`) - it's always supplied by Hypothesis so we don't 

43 need to emit the no-value-for-parameter lint. 

44 """ 

45 assert isinstance(node.args.args, list) 

46 del node.args.args[0] 

47 del node.args.annotations[0] 

48 del node.args.type_comment_args[0] 

49 return node 

50 

51 

52def register(manager: AstroidManager) -> None: 

53 manager.register_transform( 

54 node_class=FunctionDef, 

55 transform=remove_draw_parameter_from_composite_strategy, 

56 predicate=is_decorated_with_st_composite, 

57 )