Coverage for src/rejuvenation/remove_unused_variable.py: 85%

1"""AI: Example script demonstrating removal of unused variables from C source via the cleanup refactoring recipe.""" 

2 

3from more_itertools import flatten 

4 

5from renaissance.integrations.clang import ClangASTNode 

6from renaissance.integrations.clang.clang_json_ast_node import ClangJsonASTNode 

7from renaissance.integrations.clang.predicates import is_clang_compound_statement 

8from renaissance.recipes import CleanupRefactoring 

9from renaissance.syntax_tree import ( 

10 ASTFactory, 

11 ASTNode, 

12 ASTProcessor, 

13 ASTRewriter, 

14 ASTShower, 

15) 

16from renaissance.syntax_tree.ast_finder import find_nodes 

17from renaissance.syntax_tree.semantic_kind import SemanticKind 

18 

19example_code = """ 

20 int a = 1; 

21 int b = 2; 

22 int c = 3; 

23 int d = 4; 

24 void x(int a) { 

25 } 

26 void f(){ 

27 int unused = 0; 

28 int unused2 = 0; //must be removed 

29 if (a==1) { 

30 int unused = 0; 

31 int unused2 = 0; //should be kept 

32 int c = unused2; 

33 x(c); 

34 } 

35 } 

36 """ 

37expected_result_refactor = """ 

38 int a = 1; 

39 int b = 2; 

40 int c = 3; 

41 int d = 4; 

42 void x(int a) { 

43 } 

44 void f(){ 

45 if (a==1) { 

46 int unused2 = 0; //should be kept 

47 int c = unused2; 

48 x(c); 

49 } 

50 }""".strip() 

51 

52 

53def remove_unused_variable_using_refactor_method(node_type1: type[ASTNode]): 

54 """AI: Remove unused variables from the example code via `CleanupRefactoring.remove_unused_variables`.""" 

55 factory = ASTFactory(node_type1, []) 

56 # create translation unit 

57 atu = factory.create_from_text(example_code, "test.c") 

58 # create a Refactor 

59 refactor = ASTProcessor(atu, factory, in_memory=True) 

60 

61 CleanupRefactoring.remove_unused_variables(refactor) 

62 result = refactor.apply_to_string().strip() 

63 # print the rewritten code 

64 print(f"Using cleanup refactoring results {node_type1.__name__}:") 

65 print(result) 

66 

67 return result, expected_result_refactor 

68 

69 

70def remove_unused_variable_low_level(node_type1: type[ASTNode]): 

71 """AI: Remove unused variables from the example code using low-level pattern matching directly.""" 

72 factory = ASTFactory(ClangJsonASTNode, []) 

73 # Create a pattern factory (using the factory (hence also its args) 

74 # create translation unit 

75 atu = factory.create_from_text(example_code, "test.c") 

76 

77 # create an ASTRewriter 

78 rewriter = ASTRewriter(atu) 

79 

80 ASTShower.show_node(atu) 

81 # search matches and replace them 

82 funcs = flatten( 

83 find_nodes(func, lambda node: node.semantic_kind is SemanticKind.DECLARATION) 

84 for func in find_nodes(atu, is_clang_compound_statement) 

85 ) 

86 [rewriter.remove(node.parent, True, True) for node in funcs if len(node.referenced_by) == 0] 

87 

88 # print the rewritten code 

89 print(f"Low level results using {node_type1.__name__}:") 

90 result = rewriter.apply_to_string().strip() 

91 print(result) 

92 return result, expected_result_refactor 

93 

94 

95if __name__ == "__main__": 

96 for node_type in [ClangASTNode, ClangJsonASTNode]: 

97 remove_unused_variable_low_level(node_type) 

98 remove_unused_variable_using_refactor_method(node_type)