find_file_dependencies.py 3.9 KB

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  1. import ast
  2. from typing import List, Optional, Tuple
  3. from ._importlib import _resolve_name
  4. class _ExtractModuleReferences(ast.NodeVisitor):
  5. """
  6. Extract the list of global variables a block of code will read and write
  7. """
  8. @classmethod
  9. def run(cls, src: str, package: str) -> List[Tuple[str, Optional[str]]]:
  10. visitor = cls(package)
  11. tree = ast.parse(src)
  12. visitor.visit(tree)
  13. return list(visitor.references.keys())
  14. def __init__(self, package):
  15. super().__init__()
  16. self.package = package
  17. self.references = {}
  18. def _absmodule(self, module_name: str, level: int) -> str:
  19. if level > 0:
  20. return _resolve_name(module_name, self.package, level)
  21. return module_name
  22. def visit_Import(self, node):
  23. for alias in node.names:
  24. self.references[(alias.name, None)] = True
  25. def visit_ImportFrom(self, node):
  26. name = self._absmodule(node.module, 0 if node.level is None else node.level)
  27. for alias in node.names:
  28. # from my_package import foo
  29. # foo may be a module, so we have to add it to the list of
  30. # potential references, if import of it fails, we will ignore it
  31. if alias.name != "*":
  32. self.references[(name, alias.name)] = True
  33. else:
  34. self.references[(name, None)] = True
  35. def _grab_node_int(self, node):
  36. return node.value
  37. def _grab_node_str(self, node):
  38. return node.value
  39. def visit_Call(self, node):
  40. # __import__ calls aren't routed to the visit_Import/From nodes
  41. if hasattr(node.func, "id") and node.func.id == "__import__":
  42. try:
  43. name = self._grab_node_str(node.args[0])
  44. fromlist = []
  45. level = 0
  46. if len(node.args) > 3:
  47. for v in node.args[3].elts:
  48. fromlist.append(self._grab_node_str(v))
  49. elif hasattr(node, "keywords"):
  50. for keyword in node.keywords:
  51. if keyword.arg == "fromlist":
  52. for v in keyword.value.elts:
  53. fromlist.append(self._grab_node_str(v))
  54. if len(node.args) > 4:
  55. level = self._grab_node_int(node.args[4])
  56. elif hasattr(node, "keywords"):
  57. for keyword in node.keywords:
  58. if keyword.arg == "level":
  59. level = self._grab_node_int(keyword.value)
  60. if fromlist == []:
  61. # the top-level package (the name up till the first dot) is returned
  62. # when the fromlist argument is empty in normal import system,
  63. # we need to include top level package to match this behavior and last
  64. # level package to capture the intended dependency of user
  65. self.references[(name, None)] = True
  66. top_name = name.rsplit(".", maxsplit=1)[0]
  67. if top_name != name:
  68. top_name = self._absmodule(top_name, level)
  69. self.references[(top_name, None)] = True
  70. else:
  71. name = self._absmodule(name, level)
  72. for alias in fromlist:
  73. # fromlist args may be submodules, so we have to add the fromlist args
  74. # to the list of potential references. If import of an arg fails we
  75. # will ignore it, similar to visit_ImportFrom
  76. if alias != "*":
  77. self.references[(name, alias)] = True
  78. else:
  79. self.references[(name, None)] = True
  80. except Exception as e:
  81. return
  82. find_files_source_depends_on = _ExtractModuleReferences.run