def group_expressions(
expressions: Iterable[Tuple[ast.expr, Any]]
) -> List[Tuple[List[ast.expr], Any]]:
"""
Organise expression nodes and their values such that equivalent nodes are together.
Two nodes are considered equivalent if they have the same structure,
ignoring context (Load, Store, or Delete) and location (lineno, col_offset).
For example, this will group together the same variable name mentioned multiple times in an expression.
This will not check the values of the nodes. Equivalent nodes should have the same values,
unless threads are involved.
This is a low level API, typically you will use `interesting_expressions_grouped`.
:param expressions: pairs of AST expressions and their values, as obtained from
`Evaluator.find_expressions`, or `(node, evaluator[node])`.
:return: A list of pairs (tuples) containing:
- A list of equivalent AST expressions
- The value of the first expression node
(which should be the same for all nodes, unless threads are involved)
"""
result = {}
for node, value in expressions:
dump = ast.dump(copy_ast_without_context(node))
result.setdefault(dump, ([], value))[0].append(node)
return list(result.values())
def check_copy_ast_without_context(tree):
tree2 = copy_ast_without_context(tree)
dump1 = ast.dump(tree)
dump2 = ast.dump(tree2)
normalised_dump1 = re.sub(
r", ctx=(Load|Store|Del)\(\)",
"",
dump1
)
assert normalised_dump1 == dump2