# Copyright (c) 2015-2016 Claudiu Popa <pcmanticore@gmail.com>
# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html
# For details: https://github.com/PyCQA/astroid/blob/master/COPYING.LESSER
import contextlib
import unittest
import astroid
from astroid import extract_node
from astroid.test_utils import require_version
from astroid import InferenceError
from astroid import nodes
from astroid import util
from astroid.node_classes import AssignName, Const, Name, Starred
@contextlib.contextmanager
def _add_transform(manager, node, transform, predicate=None):
manager.register_transform(node, transform, predicate)
try:
yield
finally:
manager.unregister_transform(node, transform, predicate)
class ProtocolTests(unittest.TestCase):
def assertConstNodesEqual(self, nodes_list_expected, nodes_list_got):
self.assertEqual(len(nodes_list_expected), len(nodes_list_got))
for node in nodes_list_got:
self.assertIsInstance(node, Const)
for node, expected_value in zip(nodes_list_got, nodes_list_expected):
self.assertEqual(expected_value, node.value)
def assertNameNodesEqual(self, nodes_list_expected, nodes_list_got):
self.assertEqual(len(nodes_list_expected), len(nodes_list_got))
for node in nodes_list_got:
self.assertIsInstance(node, Name)
for node, expected_name in zip(nodes_list_got, nodes_list_expected):
self.assertEqual(expected_name, node.name)
def test_assigned_stmts_simple_for(self):
assign_stmts = extract_node("""
for a in (1, 2, 3): #@
pass
for b in range(3): #@
pass
""")
for1_assnode = next(assign_stmts[0].nodes_of_class(AssignName))
assigned = list(for1_assnode.assigned_stmts())
self.assertConstNodesEqual([1, 2, 3], assigned)
for2_assnode = next(assign_stmts[1].nodes_of_class(AssignName))
self.assertRaises(InferenceError,
list, for2_assnode.assigned_stmts())
@require_version(minver='3.0')
def test_assigned_stmts_starred_for(self):
assign_stmts = extract_node("""
for *a, b in ((1, 2, 3), (4, 5, 6, 7)): #@
pass
""")
for1_starred = next(assign_stmts.nodes_of_class(Starred))
assigned = next(for1_starred.assigned_stmts())
self.assertEqual(assigned, util.Uninferable)
def _get_starred_stmts(self, code):
assign_stmt = extract_node("{} #@".format(code))
starred = next(assign_stmt.nodes_of_class(Starred))
return next(starred.assigned_stmts())
def _helper_starred_expected_const(self, code, expected):
stmts = self._get_starred_stmts(code)
self.assertIsInstance(stmts, nodes.List)
stmts = stmts.elts
self.assertConstNodesEqual(expected, stmts)
def _helper_starred_expected(self, code, expected):
stmts = self._get_starred_stmts(code)
self.assertEqual(expected, stmts)
def _helper_starred_inference_error(self, code):
assign_stmt = extract_node("{} #@".format(code))
starred = next(assign_stmt.nodes_of_class(Starred))
self.assertRaises(InferenceError, list, starred.assigned_stmts())
@require_version(minver='3.0')
def test_assigned_stmts_starred_assnames(self):
self._helper_starred_expected_const(
"a, *b = (1, 2, 3, 4) #@", [2, 3, 4])
self._helper_starred_expected_const(
"*a, b = (1, 2, 3) #@", [1, 2])
self._helper_starred_expected_const(
"a, *b, c = (1, 2, 3, 4, 5) #@",
[2, 3, 4])
self._helper_starred_expected_const(
"a, *b = (1, 2) #@", [2])
self._helper_starred_expected_const(
"*b, a = (1, 2) #@", [1])
self._helper_starred_expected_const(
"[*b] = (1, 2) #@", [1, 2])
@require_version(minver='3.0')
def test_assigned_stmts_starred_yes(self):
# Not something iterable and known
self._helper_starred_expected("a, *b = range(3) #@", util.Uninferable)
# Not something inferrable
self._helper_starred_expected("a, *b = balou() #@", util.Uninferable)
# In function, unknown.
self._helper_starred_expected("""
def test(arg):
head, *tail = arg #@""", util.Uninferable)
# These cases aren't worth supporting.
self._helper_starred_expected(
"a, (*b, c), d = (1, (2, 3, 4), 5) #@", util.Uninferable)
@require_version(minver='3.0')
def test_assign_stmts_starred_fails(self):
# Too many starred
self._helper_starred_inference_error("a, *b, *c = (1, 2, 3) #@")
# Too many lhs values
self._helper_starred_inference_error("a, *b, c = (1, 2) #@")
# This could be solved properly, but it complicates needlessly the
# code for assigned_stmts, without offering real benefit.
self._helper_starred_inference_error(
"(*a, b), (c, *d) = (1, 2, 3), (4, 5, 6) #@")
def test_assigned_stmts_assignments(self):
assign_stmts = extract_node("""
c = a #@
d, e = b, c #@
""")
simple_assnode = next(assign_stmts[0].nodes_of_class(AssignName))
assigned = list(simple_assnode.assigned_stmts())
self.assertNameNodesEqual(['a'], assigned)
assnames = assign_stmts[1].nodes_of_class(AssignName)
simple_mul_assnode_1 = next(assnames)
assigned = list(simple_mul_assnode_1.assigned_stmts())
self.assertNameNodesEqual(['b'], assigned)
simple_mul_assnode_2 = next(assnames)
assigned = list(simple_mul_assnode_2.assigned_stmts())
self.assertNameNodesEqual(['c'], assigned)
@require_version(minver='3.6')
def test_assigned_stmts_annassignments(self):
annassign_stmts = extract_node("""
a: str = "abc" #@
b: str #@
""")
simple_annassign_node = next(annassign_stmts[0].nodes_of_class(AssignName))
assigned = list(simple_annassign_node.assigned_stmts())
self.assertEqual(1, len(assigned))
self.assertIsInstance(assigned[0], Const)
self.assertEqual(assigned[0].value, "abc")
empty_annassign_node = next(annassign_stmts[1].nodes_of_class(AssignName))
assigned = list(empty_annassign_node.assigned_stmts())
self.assertEqual(1, len(assigned))
self.assertIs(assigned[0], util.Uninferable)
def test_sequence_assigned_stmts_not_accepting_empty_node(self):
def transform(node):
node.root().locals['__all__'] = [node.value]
manager = astroid.MANAGER
with _add_transform(manager, astroid.Assign, transform):
module = astroid.parse('''
__all__ = ['a']
''')
module.wildcard_import_names()
if __name__ == '__main__':
unittest.main()