def assertDepends(self, source, edges, undefined=None, modified=None):
mod = ast.parse(source)
gen = GraphGen(call_deps=True)
gen.visit(mod)
self.assertSetEqual(set(gen.graph.edges()), edges)
if undefined is not None:
self.assertSetEqual(set(gen.undefined), undefined)
if modified is not None:
self.assertSetEqual(set(gen.modified), modified)
tested.update(mod)
return gen
def assertDepends(self, source, edges, undefined=None, modified=None):
mod = ast.parse(source)
gen = GraphGen(call_deps=True)
gen.visit(mod)
self.assertSetEqual(set(gen.graph.edges()), edges)
if undefined is not None:
self.assertSetEqual(set(gen.undefined), undefined)
if modified is not None:
self.assertSetEqual(set(gen.modified), modified)
tested.update(mod)
return gen
def remove_unused_assign(root, symbol):
'''
Remove redundant statements.
The statement `a = 1` will be removed::
a = 1
a = 2
The statement `a = 1` will not be removed because `b` depends on it::
a = 1
b = a + 2
a = 2
:param root: ast node
'''
gen = GatherAssignments()
gen.visit(root)
to_remove = []
if symbol not in gen.assign_id_map:
return
assignments = gen.assign_id_map[symbol]
if len(assignments) < 2:
return
for j in range(len(assignments) - 1):
i1 = root.body.index(assignments[j].root)
i2 = root.body.index(assignments[j + 1].root)
body = root.body[i1 + 1:i2]
grapher = GraphGen()
for stmnt in body:
grapher.visit(stmnt)
if symbol not in grapher.used:
to_remove.extend(assignments[j].assignments)
Pass = lambda node: _ast.Pass(lineno=node.lineno, col_offset=node.col_offset)
for old in to_remove:
replace_nodes(root, old, Pass(old))