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chromium/external/github.com/python/cpython/df4f0cbfad8a1ed0146cabd30d01efd135d4d048/./Lib/test/test_ast/test_ast.py
blob: 77596eca5d8b74798beae5fb778fa85fbc7ae55b [file]
import ast
import builtins
import copy
import dis
import enum
import os
import re
import sys
import textwrap
import types
import unittest
import weakref
from textwrap import dedent
try:
import _testinternalcapi
except ImportError:
_testinternalcapi = None
from test import support
from test.support import os_helper, script_helper
from test.support.ast_helper import ASTTestMixin
from test.test_ast.utils import to_tuple
from test.test_ast.snippets import (
eval_tests, eval_results, exec_tests, exec_results, single_tests, single_results
)
STDLIB = os.path.dirname(ast.__file__)
STDLIB_FILES = [fn for fn in os.listdir(STDLIB) if fn.endswith(".py")]
STDLIB_FILES.extend(["test/test_grammar.py", "test/test_unpack_ex.py"])
class AST_Tests(unittest.TestCase):
maxDiff = None
def _is_ast_node(self, name, node):
if not isinstance(node, type):
return False
if "ast" not in node.__module__:
return False
return name != 'AST' and name[0].isupper()
def _assertTrueorder(self, ast_node, parent_pos):
if not isinstance(ast_node, ast.AST) or ast_node._fields is None:
return
if isinstance(ast_node, (ast.expr, ast.stmt, ast.excepthandler)):
node_pos = (ast_node.lineno, ast_node.col_offset)
self.assertGreaterEqual(node_pos, parent_pos)
parent_pos = (ast_node.lineno, ast_node.col_offset)
for name in ast_node._fields:
value = getattr(ast_node, name)
if isinstance(value, list):
first_pos = parent_pos
if value and name == 'decorator_list':
first_pos = (value[0].lineno, value[0].col_offset)
for child in value:
self._assertTrueorder(child, first_pos)
elif value is not None:
self._assertTrueorder(value, parent_pos)
self.assertEqual(ast_node._fields, ast_node.__match_args__)
def test_AST_objects(self):
x = ast.AST()
self.assertEqual(x._fields, ())
x.foobar = 42
self.assertEqual(x.foobar, 42)
self.assertEqual(x.__dict__["foobar"], 42)
with self.assertRaises(AttributeError):
x.vararg
with self.assertRaises(TypeError):
# "ast.AST constructor takes 0 positional arguments"
ast.AST(2)
def test_AST_garbage_collection(self):
class X:
pass
a = ast.AST()
a.x = X()
a.x.a = a
ref = weakref.ref(a.x)
del a
support.gc_collect()
self.assertIsNone(ref())
def test_snippets(self):
for input, output, kind in ((exec_tests, exec_results, "exec"),
(single_tests, single_results, "single"),
(eval_tests, eval_results, "eval")):
for i, o in zip(input, output):
with self.subTest(action="parsing", input=i):
ast_tree = compile(i, "?", kind, ast.PyCF_ONLY_AST)
self.assertEqual(to_tuple(ast_tree), o)
self._assertTrueorder(ast_tree, (0, 0))
with self.subTest(action="compiling", input=i, kind=kind):
compile(ast_tree, "?", kind)
def test_ast_validation(self):
# compile() is the only function that calls PyAST_Validate
snippets_to_validate = exec_tests + single_tests + eval_tests
for snippet in snippets_to_validate:
tree = ast.parse(snippet)
compile(tree, '<string>', 'exec')
def test_optimization_levels__debug__(self):
cases = [(-1, '__debug__'), (0, '__debug__'), (1, False), (2, False)]
for (optval, expected) in cases:
with self.subTest(optval=optval, expected=expected):
res1 = ast.parse("__debug__", optimize=optval)
res2 = ast.parse(ast.parse("__debug__"), optimize=optval)
for res in [res1, res2]:
self.assertIsInstance(res.body[0], ast.Expr)
if isinstance(expected, bool):
self.assertIsInstance(res.body[0].value, ast.Constant)
self.assertEqual(res.body[0].value.value, expected)
else:
self.assertIsInstance(res.body[0].value, ast.Name)
self.assertEqual(res.body[0].value.id, expected)
def test_optimization_levels_const_folding(self):
folded = ('Expr', (1, 0, 1, 5), ('Constant', (1, 0, 1, 5), 3, None))
not_folded = ('Expr', (1, 0, 1, 5),
('BinOp', (1, 0, 1, 5),
('Constant', (1, 0, 1, 1), 1, None),
('Add',),
('Constant', (1, 4, 1, 5), 2, None)))
cases = [(-1, not_folded), (0, not_folded), (1, folded), (2, folded)]
for (optval, expected) in cases:
with self.subTest(optval=optval):
tree1 = ast.parse("1 + 2", optimize=optval)
tree2 = ast.parse(ast.parse("1 + 2"), optimize=optval)
for tree in [tree1, tree2]:
res = to_tuple(tree.body[0])
self.assertEqual(res, expected)
def test_invalid_position_information(self):
invalid_linenos = [
(10, 1), (-10, -11), (10, -11), (-5, -2), (-5, 1)
]
for lineno, end_lineno in invalid_linenos:
with self.subTest(f"Check invalid linenos {lineno}:{end_lineno}"):
snippet = "a = 1"
tree = ast.parse(snippet)
tree.body[0].lineno = lineno
tree.body[0].end_lineno = end_lineno
with self.assertRaises(ValueError):
compile(tree, '<string>', 'exec')
invalid_col_offsets = [
(10, 1), (-10, -11), (10, -11), (-5, -2), (-5, 1)
]
for col_offset, end_col_offset in invalid_col_offsets:
with self.subTest(f"Check invalid col_offset {col_offset}:{end_col_offset}"):
snippet = "a = 1"
tree = ast.parse(snippet)
tree.body[0].col_offset = col_offset
tree.body[0].end_col_offset = end_col_offset
with self.assertRaises(ValueError):
compile(tree, '<string>', 'exec')
def test_compilation_of_ast_nodes_with_default_end_position_values(self):
tree = ast.Module(body=[
ast.Import(names=[ast.alias(name='builtins', lineno=1, col_offset=0)], lineno=1, col_offset=0),
ast.Import(names=[ast.alias(name='traceback', lineno=0, col_offset=0)], lineno=0, col_offset=1)
], type_ignores=[])
# Check that compilation doesn't crash. Note: this may crash explicitly only on debug mode.
compile(tree, "<string>", "exec")
def test_slice(self):
slc = ast.parse("x[::]").body[0].value.slice
self.assertIsNone(slc.upper)
self.assertIsNone(slc.lower)
self.assertIsNone(slc.step)
def test_from_import(self):
im = ast.parse("from . import y").body[0]
self.assertIsNone(im.module)
def test_non_interned_future_from_ast(self):
mod = ast.parse("from __future__ import division")
self.assertIsInstance(mod.body[0], ast.ImportFrom)
mod.body[0].module = " __future__ ".strip()
compile(mod, "<test>", "exec")
def test_alias(self):
im = ast.parse("from bar import y").body[0]
self.assertEqual(len(im.names), 1)
alias = im.names[0]
self.assertEqual(alias.name, 'y')
self.assertIsNone(alias.asname)
self.assertEqual(alias.lineno, 1)
self.assertEqual(alias.end_lineno, 1)
self.assertEqual(alias.col_offset, 16)
self.assertEqual(alias.end_col_offset, 17)
im = ast.parse("from bar import *").body[0]
alias = im.names[0]
self.assertEqual(alias.name, '*')
self.assertIsNone(alias.asname)
self.assertEqual(alias.lineno, 1)
self.assertEqual(alias.end_lineno, 1)
self.assertEqual(alias.col_offset, 16)
self.assertEqual(alias.end_col_offset, 17)
im = ast.parse("from bar import y as z").body[0]
alias = im.names[0]
self.assertEqual(alias.name, "y")
self.assertEqual(alias.asname, "z")
self.assertEqual(alias.lineno, 1)
self.assertEqual(alias.end_lineno, 1)
self.assertEqual(alias.col_offset, 16)
self.assertEqual(alias.end_col_offset, 22)
im = ast.parse("import bar as foo").body[0]
alias = im.names[0]
self.assertEqual(alias.name, "bar")
self.assertEqual(alias.asname, "foo")
self.assertEqual(alias.lineno, 1)
self.assertEqual(alias.end_lineno, 1)
self.assertEqual(alias.col_offset, 7)
self.assertEqual(alias.end_col_offset, 17)
def test_base_classes(self):
self.assertTrue(issubclass(ast.For, ast.stmt))
self.assertTrue(issubclass(ast.Name, ast.expr))
self.assertTrue(issubclass(ast.stmt, ast.AST))
self.assertTrue(issubclass(ast.expr, ast.AST))
self.assertTrue(issubclass(ast.comprehension, ast.AST))
self.assertTrue(issubclass(ast.Gt, ast.AST))
def test_field_attr_existence(self):
for name, item in ast.__dict__.items():
# constructor has a different signature
if name == 'Index':
continue
if self._is_ast_node(name, item):
x = self._construct_ast_class(item)
if isinstance(x, ast.AST):
self.assertIs(type(x._fields), tuple)
def _construct_ast_class(self, cls):
kwargs = {}
for name, typ in cls.__annotations__.items():
if typ is str:
kwargs[name] = 'capybara'
elif typ is int:
kwargs[name] = 42
elif typ is object:
kwargs[name] = b'capybara'
elif isinstance(typ, type) and issubclass(typ, ast.AST):
kwargs[name] = self._construct_ast_class(typ)
return cls(**kwargs)
def test_arguments(self):
x = ast.arguments()
self.assertEqual(x._fields, ('posonlyargs', 'args', 'vararg', 'kwonlyargs',
'kw_defaults', 'kwarg', 'defaults'))
self.assertEqual(x.__annotations__, {
'posonlyargs': list[ast.arg],
'args': list[ast.arg],
'vararg': ast.arg | None,
'kwonlyargs': list[ast.arg],
'kw_defaults': list[ast.expr],
'kwarg': ast.arg | None,
'defaults': list[ast.expr],
})
self.assertEqual(x.args, [])
self.assertIsNone(x.vararg)
x = ast.arguments(*range(1, 8))
self.assertEqual(x.args, 2)
self.assertEqual(x.vararg, 3)
def test_field_attr_writable(self):
x = ast.Constant(1)
# We can assign to _fields
x._fields = 666
self.assertEqual(x._fields, 666)
def test_classattrs(self):
with self.assertWarns(DeprecationWarning):
x = ast.Constant()
self.assertEqual(x._fields, ('value', 'kind'))
with self.assertRaises(AttributeError):
x.value
x = ast.Constant(42)
self.assertEqual(x.value, 42)
with self.assertRaises(AttributeError):
x.lineno
with self.assertRaises(AttributeError):
x.foobar
x = ast.Constant(lineno=2, value=3)
self.assertEqual(x.lineno, 2)
x = ast.Constant(42, lineno=0)
self.assertEqual(x.lineno, 0)
self.assertEqual(x._fields, ('value', 'kind'))
self.assertEqual(x.value, 42)
self.assertRaises(TypeError, ast.Constant, 1, None, 2)
self.assertRaises(TypeError, ast.Constant, 1, None, 2, lineno=0)
# Arbitrary keyword arguments are supported (but deprecated)
with self.assertWarns(DeprecationWarning):
self.assertEqual(ast.Constant(1, foo='bar').foo, 'bar')
with self.assertRaisesRegex(TypeError, "Constant got multiple values for argument 'value'"):
ast.Constant(1, value=2)
self.assertEqual(ast.Constant(42).value, 42)
self.assertEqual(ast.Constant(4.25).value, 4.25)
self.assertEqual(ast.Constant(4.25j).value, 4.25j)
self.assertEqual(ast.Constant('42').value, '42')
self.assertEqual(ast.Constant(b'42').value, b'42')
self.assertIs(ast.Constant(True).value, True)
self.assertIs(ast.Constant(False).value, False)
self.assertIs(ast.Constant(None).value, None)
self.assertIs(ast.Constant(...).value, ...)
def test_constant_subclasses(self):
class N(ast.Constant):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.z = 'spam'
class N2(ast.Constant):
pass
n = N(42)
self.assertEqual(n.value, 42)
self.assertEqual(n.z, 'spam')
self.assertEqual(type(n), N)
self.assertTrue(isinstance(n, N))
self.assertTrue(isinstance(n, ast.Constant))
self.assertFalse(isinstance(n, N2))
self.assertFalse(isinstance(ast.Constant(42), N))
n = N(value=42)
self.assertEqual(n.value, 42)
self.assertEqual(type(n), N)
def test_module(self):
body = [ast.Constant(42)]
x = ast.Module(body, [])
self.assertEqual(x.body, body)
def test_nodeclasses(self):
# Zero arguments constructor explicitly allowed (but deprecated)
with self.assertWarns(DeprecationWarning):
x = ast.BinOp()
self.assertEqual(x._fields, ('left', 'op', 'right'))
# Random attribute allowed too
x.foobarbaz = 5
self.assertEqual(x.foobarbaz, 5)
n1 = ast.Constant(1)
n3 = ast.Constant(3)
addop = ast.Add()
x = ast.BinOp(n1, addop, n3)
self.assertEqual(x.left, n1)
self.assertEqual(x.op, addop)
self.assertEqual(x.right, n3)
x = ast.BinOp(1, 2, 3)
self.assertEqual(x.left, 1)
self.assertEqual(x.op, 2)
self.assertEqual(x.right, 3)
x = ast.BinOp(1, 2, 3, lineno=0)
self.assertEqual(x.left, 1)
self.assertEqual(x.op, 2)
self.assertEqual(x.right, 3)
self.assertEqual(x.lineno, 0)
# node raises exception when given too many arguments
self.assertRaises(TypeError, ast.BinOp, 1, 2, 3, 4)
# node raises exception when given too many arguments
self.assertRaises(TypeError, ast.BinOp, 1, 2, 3, 4, lineno=0)
# can set attributes through kwargs too
x = ast.BinOp(left=1, op=2, right=3, lineno=0)
self.assertEqual(x.left, 1)
self.assertEqual(x.op, 2)
self.assertEqual(x.right, 3)
self.assertEqual(x.lineno, 0)
# Random kwargs also allowed (but deprecated)
with self.assertWarns(DeprecationWarning):
x = ast.BinOp(1, 2, 3, foobarbaz=42)
self.assertEqual(x.foobarbaz, 42)
def test_no_fields(self):
# this used to fail because Sub._fields was None
x = ast.Sub()
self.assertEqual(x._fields, ())
def test_invalid_sum(self):
pos = dict(lineno=2, col_offset=3)
m = ast.Module([ast.Expr(ast.expr(**pos), **pos)], [])
with self.assertRaises(TypeError) as cm:
compile(m, "<test>", "exec")
self.assertIn("but got <ast.expr", str(cm.exception))
def test_invalid_identifier(self):
m = ast.Module([ast.Expr(ast.Name(42, ast.Load()))], [])
ast.fix_missing_locations(m)
with self.assertRaises(TypeError) as cm:
compile(m, "<test>", "exec")
self.assertIn("identifier must be of type str", str(cm.exception))
def test_invalid_constant(self):
for invalid_constant in int, (1, 2, int), frozenset((1, 2, int)):
e = ast.Expression(body=ast.Constant(invalid_constant))
ast.fix_missing_locations(e)
with self.assertRaisesRegex(
TypeError, "invalid type in Constant: type"
):
compile(e, "<test>", "eval")
def test_empty_yield_from(self):
# Issue 16546: yield from value is not optional.
empty_yield_from = ast.parse("def f():\n yield from g()")
empty_yield_from.body[0].body[0].value.value = None
with self.assertRaises(ValueError) as cm:
compile(empty_yield_from, "<test>", "exec")
self.assertIn("field 'value' is required", str(cm.exception))
@support.cpython_only
def test_issue31592(self):
# There shouldn't be an assertion failure in case of a bad
# unicodedata.normalize().
import unicodedata
def bad_normalize(*args):
return None
with support.swap_attr(unicodedata, 'normalize', bad_normalize):
self.assertRaises(TypeError, ast.parse, '\u03D5')
def test_issue18374_binop_col_offset(self):
tree = ast.parse('4+5+6+7')
parent_binop = tree.body[0].value
child_binop = parent_binop.left
grandchild_binop = child_binop.left
self.assertEqual(parent_binop.col_offset, 0)
self.assertEqual(parent_binop.end_col_offset, 7)
self.assertEqual(child_binop.col_offset, 0)
self.assertEqual(child_binop.end_col_offset, 5)
self.assertEqual(grandchild_binop.col_offset, 0)
self.assertEqual(grandchild_binop.end_col_offset, 3)
tree = ast.parse('4+5-\\\n 6-7')
parent_binop = tree.body[0].value
child_binop = parent_binop.left
grandchild_binop = child_binop.left
self.assertEqual(parent_binop.col_offset, 0)
self.assertEqual(parent_binop.lineno, 1)
self.assertEqual(parent_binop.end_col_offset, 4)
self.assertEqual(parent_binop.end_lineno, 2)
self.assertEqual(child_binop.col_offset, 0)
self.assertEqual(child_binop.lineno, 1)
self.assertEqual(child_binop.end_col_offset, 2)
self.assertEqual(child_binop.end_lineno, 2)
self.assertEqual(grandchild_binop.col_offset, 0)
self.assertEqual(grandchild_binop.lineno, 1)
self.assertEqual(grandchild_binop.end_col_offset, 3)
self.assertEqual(grandchild_binop.end_lineno, 1)
def test_issue39579_dotted_name_end_col_offset(self):
tree = ast.parse('@a.b.c\ndef f(): pass')
attr_b = tree.body[0].decorator_list[0].value
self.assertEqual(attr_b.end_col_offset, 4)
def test_ast_asdl_signature(self):
self.assertEqual(ast.withitem.__doc__, "withitem(expr context_expr, expr? optional_vars)")
self.assertEqual(ast.GtE.__doc__, "GtE")
self.assertEqual(ast.Name.__doc__, "Name(identifier id, expr_context ctx)")
self.assertEqual(ast.cmpop.__doc__, "cmpop = Eq | NotEq | Lt | LtE | Gt | GtE | Is | IsNot | In | NotIn")
expressions = [f" | {node.__doc__}" for node in ast.expr.__subclasses__()]
expressions[0] = f"expr = {ast.expr.__subclasses__()[0].__doc__}"
self.assertCountEqual(ast.expr.__doc__.split("\n"), expressions)
def test_compare_basics(self):
self.assertTrue(ast.compare(ast.parse("x = 10"), ast.parse("x = 10")))
self.assertFalse(ast.compare(ast.parse("x = 10"), ast.parse("")))
self.assertFalse(ast.compare(ast.parse("x = 10"), ast.parse("x")))
self.assertFalse(
ast.compare(ast.parse("x = 10;y = 20"), ast.parse("class C:pass"))
)
def test_compare_modified_ast(self):
# The ast API is a bit underspecified. The objects are mutable,
# and even _fields and _attributes are mutable. The compare() does
# some simple things to accommodate mutability.
a = ast.parse("m * x + b", mode="eval")
b = ast.parse("m * x + b", mode="eval")
self.assertTrue(ast.compare(a, b))
a._fields = a._fields + ("spam",)
a.spam = "Spam"
self.assertNotEqual(a._fields, b._fields)
self.assertFalse(ast.compare(a, b))
self.assertFalse(ast.compare(b, a))
b._fields = a._fields
b.spam = a.spam
self.assertTrue(ast.compare(a, b))
self.assertTrue(ast.compare(b, a))
b._attributes = b._attributes + ("eggs",)
b.eggs = "eggs"
self.assertNotEqual(a._attributes, b._attributes)
self.assertFalse(ast.compare(a, b, compare_attributes=True))
self.assertFalse(ast.compare(b, a, compare_attributes=True))
a._attributes = b._attributes
a.eggs = b.eggs
self.assertTrue(ast.compare(a, b, compare_attributes=True))
self.assertTrue(ast.compare(b, a, compare_attributes=True))
def test_compare_literals(self):
constants = (
-20,
20,
20.0,
1,
1.0,
True,
0,
False,
frozenset(),
tuple(),
"ABCD",
"abcd",
"中文字",
1e1000,
-1e1000,
)
for next_index, constant in enumerate(constants[:-1], 1):
next_constant = constants[next_index]
with self.subTest(literal=constant, next_literal=next_constant):
self.assertTrue(
ast.compare(ast.Constant(constant), ast.Constant(constant))
)
self.assertFalse(
ast.compare(
ast.Constant(constant), ast.Constant(next_constant)
)
)
same_looking_literal_cases = [
{1, 1.0, True, 1 + 0j},
{0, 0.0, False, 0 + 0j},
]
for same_looking_literals in same_looking_literal_cases:
for literal in same_looking_literals:
for same_looking_literal in same_looking_literals - {literal}:
self.assertFalse(
ast.compare(
ast.Constant(literal),
ast.Constant(same_looking_literal),
)
)
def test_compare_fieldless(self):
self.assertTrue(ast.compare(ast.Add(), ast.Add()))
self.assertFalse(ast.compare(ast.Sub(), ast.Add()))
# test that missing runtime fields is handled in ast.compare()
a1, a2 = ast.Name('a'), ast.Name('a')
self.assertTrue(ast.compare(a1, a2))
self.assertTrue(ast.compare(a1, a2))
del a1.id
self.assertFalse(ast.compare(a1, a2))
del a2.id
self.assertTrue(ast.compare(a1, a2))
def test_compare_modes(self):
for mode, sources in (
("exec", exec_tests),
("eval", eval_tests),
("single", single_tests),
):
for source in sources:
a = ast.parse(source, mode=mode)
b = ast.parse(source, mode=mode)
self.assertTrue(
ast.compare(a, b), f"{ast.dump(a)} != {ast.dump(b)}"
)
def test_compare_attributes_option(self):
def parse(a, b):
return ast.parse(a), ast.parse(b)
a, b = parse("2 + 2", "2+2")
self.assertTrue(ast.compare(a, b))
self.assertTrue(ast.compare(a, b, compare_attributes=False))
self.assertFalse(ast.compare(a, b, compare_attributes=True))
def test_compare_attributes_option_missing_attribute(self):
# test that missing runtime attributes is handled in ast.compare()
a1, a2 = ast.Name('a', lineno=1), ast.Name('a', lineno=1)
self.assertTrue(ast.compare(a1, a2))
self.assertTrue(ast.compare(a1, a2, compare_attributes=True))
del a1.lineno
self.assertFalse(ast.compare(a1, a2, compare_attributes=True))
del a2.lineno
self.assertTrue(ast.compare(a1, a2, compare_attributes=True))
def test_positional_only_feature_version(self):
ast.parse('def foo(x, /): ...', feature_version=(3, 8))
ast.parse('def bar(x=1, /): ...', feature_version=(3, 8))
with self.assertRaises(SyntaxError):
ast.parse('def foo(x, /): ...', feature_version=(3, 7))
with self.assertRaises(SyntaxError):
ast.parse('def bar(x=1, /): ...', feature_version=(3, 7))
ast.parse('lambda x, /: ...', feature_version=(3, 8))
ast.parse('lambda x=1, /: ...', feature_version=(3, 8))
with self.assertRaises(SyntaxError):
ast.parse('lambda x, /: ...', feature_version=(3, 7))
with self.assertRaises(SyntaxError):
ast.parse('lambda x=1, /: ...', feature_version=(3, 7))
def test_assignment_expression_feature_version(self):
ast.parse('(x := 0)', feature_version=(3, 8))
with self.assertRaises(SyntaxError):
ast.parse('(x := 0)', feature_version=(3, 7))
def test_conditional_context_managers_parse_with_low_feature_version(self):
# regression test for gh-115881
ast.parse('with (x() if y else z()): ...', feature_version=(3, 8))
def test_exception_groups_feature_version(self):
code = dedent('''
try: ...
except* Exception: ...
''')
ast.parse(code)
with self.assertRaises(SyntaxError):
ast.parse(code, feature_version=(3, 10))
def test_type_params_feature_version(self):
samples = [
"type X = int",
"class X[T]: pass",
"def f[T](): pass",
]
for sample in samples:
with self.subTest(sample):
ast.parse(sample)
with self.assertRaises(SyntaxError):
ast.parse(sample, feature_version=(3, 11))
def test_type_params_default_feature_version(self):
samples = [
"type X[*Ts=int] = int",
"class X[T=int]: pass",
"def f[**P=int](): pass",
]
for sample in samples:
with self.subTest(sample):
ast.parse(sample)
with self.assertRaises(SyntaxError):
ast.parse(sample, feature_version=(3, 12))
def test_invalid_major_feature_version(self):
with self.assertRaises(ValueError):
ast.parse('pass', feature_version=(2, 7))
with self.assertRaises(ValueError):
ast.parse('pass', feature_version=(4, 0))
def test_constant_as_name(self):
for constant in "True", "False", "None":
expr = ast.Expression(ast.Name(constant, ast.Load()))
ast.fix_missing_locations(expr)
with self.assertRaisesRegex(ValueError, f"identifier field can't represent '{constant}' constant"):
compile(expr, "<test>", "eval")
def test_precedence_enum(self):
class _Precedence(enum.IntEnum):
"""Precedence table that originated from python grammar."""
NAMED_EXPR = enum.auto() # <target> := <expr1>
TUPLE = enum.auto() # <expr1>, <expr2>
YIELD = enum.auto() # 'yield', 'yield from'
TEST = enum.auto() # 'if'-'else', 'lambda'
OR = enum.auto() # 'or'
AND = enum.auto() # 'and'
NOT = enum.auto() # 'not'
CMP = enum.auto() # '<', '>', '==', '>=', '<=', '!=',
# 'in', 'not in', 'is', 'is not'
EXPR = enum.auto()
BOR = EXPR # '|'
BXOR = enum.auto() # '^'
BAND = enum.auto() # '&'
SHIFT = enum.auto() # '<<', '>>'
ARITH = enum.auto() # '+', '-'
TERM = enum.auto() # '*', '@', '/', '%', '//'
FACTOR = enum.auto() # unary '+', '-', '~'
POWER = enum.auto() # '**'
AWAIT = enum.auto() # 'await'
ATOM = enum.auto()
def next(self):
try:
return self.__class__(self + 1)
except ValueError:
return self
enum._test_simple_enum(_Precedence, ast._Precedence)
@support.cpython_only
def test_ast_recursion_limit(self):
fail_depth = support.exceeds_recursion_limit()
crash_depth = 100_000
success_depth = int(support.get_c_recursion_limit() * 0.8)
if _testinternalcapi is not None:
remaining = _testinternalcapi.get_c_recursion_remaining()
success_depth = min(success_depth, remaining)
def check_limit(prefix, repeated):
expect_ok = prefix + repeated * success_depth
ast.parse(expect_ok)
for depth in (fail_depth, crash_depth):
broken = prefix + repeated * depth
details = "Compiling ({!r} + {!r} * {})".format(
prefix, repeated, depth)
with self.assertRaises(RecursionError, msg=details):
with support.infinite_recursion():
ast.parse(broken)
check_limit("a", "()")
check_limit("a", ".b")
check_limit("a", "[0]")
check_limit("a", "*a")
def test_null_bytes(self):
with self.assertRaises(SyntaxError,
msg="source code string cannot contain null bytes"):
ast.parse("a\0b")
def assert_none_check(self, node: type[ast.AST], attr: str, source: str) -> None:
with self.subTest(f"{node.__name__}.{attr}"):
tree = ast.parse(source)
found = 0
for child in ast.walk(tree):
if isinstance(child, node):
setattr(child, attr, None)
found += 1
self.assertEqual(found, 1)
e = re.escape(f"field '{attr}' is required for {node.__name__}")
with self.assertRaisesRegex(ValueError, f"^{e}$"):
compile(tree, "<test>", "exec")
def test_none_checks(self) -> None:
tests = [
(ast.alias, "name", "import spam as SPAM"),
(ast.arg, "arg", "def spam(SPAM): spam"),
(ast.comprehension, "target", "[spam for SPAM in spam]"),
(ast.comprehension, "iter", "[spam for spam in SPAM]"),
(ast.keyword, "value", "spam(**SPAM)"),
(ast.match_case, "pattern", "match spam:\n case SPAM: spam"),
(ast.withitem, "context_expr", "with SPAM: spam"),
]
for node, attr, source in tests:
self.assert_none_check(node, attr, source)
class CopyTests(unittest.TestCase):
"""Test copying and pickling AST nodes."""
@staticmethod
def iter_ast_classes():
"""Iterate over the (native) subclasses of ast.AST recursively.
This excludes the special class ast.Index since its constructor
returns an integer.
"""
def do(cls):
if cls.__module__ != 'ast':
return
if cls is ast.Index:
return
yield cls
for sub in cls.__subclasses__():
yield from do(sub)
yield from do(ast.AST)
def test_pickling(self):
import pickle
for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
for code in exec_tests:
with self.subTest(code=code, protocol=protocol):
tree = compile(code, "?", "exec", 0x400)
ast2 = pickle.loads(pickle.dumps(tree, protocol))
self.assertEqual(to_tuple(ast2), to_tuple(tree))
def test_copy_with_parents(self):
# gh-120108
code = """
('',)
while i < n:
if ch == '':
ch = format[i]
if ch == '':
if freplace is None:
'' % getattr(object)
elif ch == '':
if zreplace is None:
if hasattr:
offset = object.utcoffset()
if offset is not None:
if offset.days < 0:
offset = -offset
h = divmod(timedelta(hours=0))
if u:
zreplace = '' % (sign,)
elif s:
zreplace = '' % (sign,)
else:
zreplace = '' % (sign,)
elif ch == '':
if Zreplace is None:
Zreplace = ''
if hasattr(object):
s = object.tzname()
if s is not None:
Zreplace = s.replace('')
newformat.append(Zreplace)
else:
push('')
else:
push(ch)
"""
tree = ast.parse(textwrap.dedent(code))
for node in ast.walk(tree):
for child in ast.iter_child_nodes(node):
child.parent = node
try:
with support.infinite_recursion(200):
tree2 = copy.deepcopy(tree)
finally:
# Singletons like ast.Load() are shared; make sure we don't
# leave them mutated after this test.
for node in ast.walk(tree):
if hasattr(node, "parent"):
del node.parent
for node in ast.walk(tree2):
for child in ast.iter_child_nodes(node):
if hasattr(child, "parent") and not isinstance(child, (
ast.expr_context, ast.boolop, ast.unaryop, ast.cmpop, ast.operator,
)):
self.assertEqual(to_tuple(child.parent), to_tuple(node))
def test_replace_interface(self):
for klass in self.iter_ast_classes():
with self.subTest(klass=klass):
self.assertTrue(hasattr(klass, '__replace__'))
fields = set(klass._fields)
with self.subTest(klass=klass, fields=fields):
node = klass(**dict.fromkeys(fields))
# forbid positional arguments in replace()
self.assertRaises(TypeError, copy.replace, node, 1)
self.assertRaises(TypeError, node.__replace__, 1)
def test_replace_native(self):
for klass in self.iter_ast_classes():
fields = set(klass._fields)
attributes = set(klass._attributes)
with self.subTest(klass=klass, fields=fields, attributes=attributes):
# use of object() to ensure that '==' and 'is'
# behave similarly in ast.compare(node, repl)
old_fields = {field: object() for field in fields}
old_attrs = {attr: object() for attr in attributes}
# check shallow copy
node = klass(**old_fields)
repl = copy.replace(node)
self.assertTrue(ast.compare(node, repl, compare_attributes=True))
# check when passing using attributes (they may be optional!)
node = klass(**old_fields, **old_attrs)
repl = copy.replace(node)
self.assertTrue(ast.compare(node, repl, compare_attributes=True))
for field in fields:
# check when we sometimes have attributes and sometimes not
for init_attrs in [{}, old_attrs]:
node = klass(**old_fields, **init_attrs)
# only change a single field (do not change attributes)
new_value = object()
repl = copy.replace(node, **{field: new_value})
for f in fields:
old_value = old_fields[f]
# assert that there is no side-effect
self.assertIs(getattr(node, f), old_value)
# check the changes
if f != field:
self.assertIs(getattr(repl, f), old_value)
else:
self.assertIs(getattr(repl, f), new_value)
self.assertFalse(ast.compare(node, repl, compare_attributes=True))
for attribute in attributes:
node = klass(**old_fields, **old_attrs)
# only change a single attribute (do not change fields)
new_attr = object()
repl = copy.replace(node, **{attribute: new_attr})
for a in attributes:
old_attr = old_attrs[a]
# assert that there is no side-effect
self.assertIs(getattr(node, a), old_attr)
# check the changes
if a != attribute:
self.assertIs(getattr(repl, a), old_attr)
else:
self.assertIs(getattr(repl, a), new_attr)
self.assertFalse(ast.compare(node, repl, compare_attributes=True))
def test_replace_accept_known_class_fields(self):
nid, ctx = object(), object()
node = ast.Name(id=nid, ctx=ctx)
self.assertIs(node.id, nid)
self.assertIs(node.ctx, ctx)
new_nid = object()
repl = copy.replace(node, id=new_nid)
# assert that there is no side-effect
self.assertIs(node.id, nid)
self.assertIs(node.ctx, ctx)
# check the changes
self.assertIs(repl.id, new_nid)
self.assertIs(repl.ctx, node.ctx) # no changes
def test_replace_accept_known_class_attributes(self):
node = ast.parse('x').body[0].value
self.assertEqual(node.id, 'x')
self.assertEqual(node.lineno, 1)
# constructor allows any type so replace() should do the same
lineno = object()
repl = copy.replace(node, lineno=lineno)
# assert that there is no side-effect
self.assertEqual(node.lineno, 1)
# check the changes
self.assertEqual(repl.id, node.id)
self.assertEqual(repl.ctx, node.ctx)
self.assertEqual(repl.lineno, lineno)
_, _, state = node.__reduce__()
self.assertEqual(state['id'], 'x')
self.assertEqual(state['ctx'], node.ctx)
self.assertEqual(state['lineno'], 1)
_, _, state = repl.__reduce__()
self.assertEqual(state['id'], 'x')
self.assertEqual(state['ctx'], node.ctx)
self.assertEqual(state['lineno'], lineno)
def test_replace_accept_known_custom_class_fields(self):
class MyNode(ast.AST):
_fields = ('name', 'data')
__annotations__ = {'name': str, 'data': object}
__match_args__ = ('name', 'data')
name, data = 'name', object()
node = MyNode(name, data)
self.assertIs(node.name, name)
self.assertIs(node.data, data)
# check shallow copy
repl = copy.replace(node)
# assert that there is no side-effect
self.assertIs(node.name, name)
self.assertIs(node.data, data)
# check the shallow copy
self.assertIs(repl.name, name)
self.assertIs(repl.data, data)
node = MyNode(name, data)
repl_data = object()
# replace custom but known field
repl = copy.replace(node, data=repl_data)
# assert that there is no side-effect
self.assertIs(node.name, name)
self.assertIs(node.data, data)
# check the changes
self.assertIs(repl.name, node.name)
self.assertIs(repl.data, repl_data)
def test_replace_accept_known_custom_class_attributes(self):
class MyNode(ast.AST):
x = 0
y = 1
_attributes = ('x', 'y')
node = MyNode()
self.assertEqual(node.x, 0)
self.assertEqual(node.y, 1)
y = object()
repl = copy.replace(node, y=y)
# assert that there is no side-effect
self.assertEqual(node.x, 0)
self.assertEqual(node.y, 1)
# check the changes
self.assertEqual(repl.x, 0)
self.assertEqual(repl.y, y)
def test_replace_ignore_known_custom_instance_fields(self):
node = ast.parse('x').body[0].value
node.extra = extra = object() # add instance 'extra' field
context = node.ctx
# assert initial values
self.assertIs(node.id, 'x')
self.assertIs(node.ctx, context)
self.assertIs(node.extra, extra)
# shallow copy, but drops extra fields
repl = copy.replace(node)
# assert that there is no side-effect
self.assertIs(node.id, 'x')
self.assertIs(node.ctx, context)
self.assertIs(node.extra, extra)
# verify that the 'extra' field is not kept
self.assertIs(repl.id, 'x')
self.assertIs(repl.ctx, context)
self.assertRaises(AttributeError, getattr, repl, 'extra')
# change known native field
repl = copy.replace(node, id='y')
# assert that there is no side-effect
self.assertIs(node.id, 'x')
self.assertIs(node.ctx, context)
self.assertIs(node.extra, extra)
# verify that the 'extra' field is not kept
self.assertIs(repl.id, 'y')
self.assertIs(repl.ctx, context)
self.assertRaises(AttributeError, getattr, repl, 'extra')
def test_replace_reject_missing_field(self):
# case: warn if deleted field is not replaced
node = ast.parse('x').body[0].value
context = node.ctx
del node.id
self.assertRaises(AttributeError, getattr, node, 'id')
self.assertIs(node.ctx, context)
msg = "Name.__replace__ missing 1 keyword argument: 'id'."
with self.assertRaisesRegex(TypeError, re.escape(msg)):
copy.replace(node)
# assert that there is no side-effect
self.assertRaises(AttributeError, getattr, node, 'id')
self.assertIs(node.ctx, context)
# case: do not raise if deleted field is replaced
node = ast.parse('x').body[0].value
context = node.ctx
del node.id
self.assertRaises(AttributeError, getattr, node, 'id')
self.assertIs(node.ctx, context)
repl = copy.replace(node, id='y')
# assert that there is no side-effect
self.assertRaises(AttributeError, getattr, node, 'id')
self.assertIs(node.ctx, context)
self.assertIs(repl.id, 'y')
self.assertIs(repl.ctx, context)
def test_replace_reject_known_custom_instance_fields_commits(self):
node = ast.parse('x').body[0].value
node.extra = extra = object() # add instance 'extra' field
context = node.ctx
# explicit rejection of known instance fields
self.assertTrue(hasattr(node, 'extra'))
msg = "Name.__replace__ got an unexpected keyword argument 'extra'."
with self.assertRaisesRegex(TypeError, re.escape(msg)):
copy.replace(node, extra=1)
# assert that there is no side-effect
self.assertIs(node.id, 'x')
self.assertIs(node.ctx, context)
self.assertIs(node.extra, extra)
def test_replace_reject_unknown_instance_fields(self):
node = ast.parse('x').body[0].value
context = node.ctx
# explicit rejection of unknown extra fields
self.assertRaises(AttributeError, getattr, node, 'unknown')
msg = "Name.__replace__ got an unexpected keyword argument 'unknown'."
with self.assertRaisesRegex(TypeError, re.escape(msg)):
copy.replace(node, unknown=1)
# assert that there is no side-effect
self.assertIs(node.id, 'x')
self.assertIs(node.ctx, context)
self.assertRaises(AttributeError, getattr, node, 'unknown')
class ASTHelpers_Test(unittest.TestCase):
maxDiff = None
def test_parse(self):
a = ast.parse('foo(1 + 1)')
b = compile('foo(1 + 1)', '<unknown>', 'exec', ast.PyCF_ONLY_AST)
self.assertEqual(ast.dump(a), ast.dump(b))
def test_parse_in_error(self):
try:
1/0
except Exception:
with self.assertRaises(SyntaxError) as e:
ast.literal_eval(r"'\U'")
self.assertIsNotNone(e.exception.__context__)
def test_dump(self):
node = ast.parse('spam(eggs, "and cheese")')
self.assertEqual(ast.dump(node),
"Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load()), "
"args=[Name(id='eggs', ctx=Load()), Constant(value='and cheese')]))])"
)
self.assertEqual(ast.dump(node, annotate_fields=False),
"Module([Expr(Call(Name('spam', Load()), [Name('eggs', Load()), "
"Constant('and cheese')]))])"
)
self.assertEqual(ast.dump(node, include_attributes=True),
"Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load(), "
"lineno=1, col_offset=0, end_lineno=1, end_col_offset=4), "
"args=[Name(id='eggs', ctx=Load(), lineno=1, col_offset=5, "
"end_lineno=1, end_col_offset=9), Constant(value='and cheese', "
"lineno=1, col_offset=11, end_lineno=1, end_col_offset=23)], "
"lineno=1, col_offset=0, end_lineno=1, end_col_offset=24), "
"lineno=1, col_offset=0, end_lineno=1, end_col_offset=24)])"
)
def test_dump_indent(self):
node = ast.parse('spam(eggs, "and cheese")')
self.assertEqual(ast.dump(node, indent=3), """\
Module(
body=[
Expr(
value=Call(
func=Name(id='spam', ctx=Load()),
args=[
Name(id='eggs', ctx=Load()),
Constant(value='and cheese')]))])""")
self.assertEqual(ast.dump(node, annotate_fields=False, indent='\t'), """\
Module(
\t[
\t\tExpr(
\t\t\tCall(
\t\t\t\tName('spam', Load()),
\t\t\t\t[
\t\t\t\t\tName('eggs', Load()),
\t\t\t\t\tConstant('and cheese')]))])""")
self.assertEqual(ast.dump(node, include_attributes=True, indent=3), """\
Module(
body=[
Expr(
value=Call(
func=Name(
id='spam',
ctx=Load(),
lineno=1,
col_offset=0,
end_lineno=1,
end_col_offset=4),
args=[
Name(
id='eggs',
ctx=Load(),
lineno=1,
col_offset=5,
end_lineno=1,
end_col_offset=9),
Constant(
value='and cheese',
lineno=1,
col_offset=11,
end_lineno=1,
end_col_offset=23)],
lineno=1,
col_offset=0,
end_lineno=1,
end_col_offset=24),
lineno=1,
col_offset=0,
end_lineno=1,
end_col_offset=24)])""")
def test_dump_incomplete(self):
node = ast.Raise(lineno=3, col_offset=4)
self.assertEqual(ast.dump(node),
"Raise()"
)
self.assertEqual(ast.dump(node, include_attributes=True),
"Raise(lineno=3, col_offset=4)"
)
node = ast.Raise(exc=ast.Name(id='e', ctx=ast.Load()), lineno=3, col_offset=4)
self.assertEqual(ast.dump(node),
"Raise(exc=Name(id='e', ctx=Load()))"
)
self.assertEqual(ast.dump(node, annotate_fields=False),
"Raise(Name('e', Load()))"
)
self.assertEqual(ast.dump(node, include_attributes=True),
"Raise(exc=Name(id='e', ctx=Load()), lineno=3, col_offset=4)"
)
self.assertEqual(ast.dump(node, annotate_fields=False, include_attributes=True),
"Raise(Name('e', Load()), lineno=3, col_offset=4)"
)
node = ast.Raise(cause=ast.Name(id='e', ctx=ast.Load()))
self.assertEqual(ast.dump(node),
"Raise(cause=Name(id='e', ctx=Load()))"
)
self.assertEqual(ast.dump(node, annotate_fields=False),
"Raise(cause=Name('e', Load()))"
)
# Arguments:
node = ast.arguments(args=[ast.arg("x")])
self.assertEqual(ast.dump(node, annotate_fields=False),
"arguments([], [arg('x')])",
)
node = ast.arguments(posonlyargs=[ast.arg("x")])
self.assertEqual(ast.dump(node, annotate_fields=False),
"arguments([arg('x')])",
)
node = ast.arguments(posonlyargs=[ast.arg("x")], kwonlyargs=[ast.arg('y')])
self.assertEqual(ast.dump(node, annotate_fields=False),
"arguments([arg('x')], kwonlyargs=[arg('y')])",
)
node = ast.arguments(args=[ast.arg("x")], kwonlyargs=[ast.arg('y')])
self.assertEqual(ast.dump(node, annotate_fields=False),
"arguments([], [arg('x')], kwonlyargs=[arg('y')])",
)
node = ast.arguments()
self.assertEqual(ast.dump(node, annotate_fields=False),
"arguments()",
)
# Classes:
node = ast.ClassDef(
'T',
[],
[ast.keyword('a', ast.Constant(None))],
[],
[ast.Name('dataclass', ctx=ast.Load())],
)
self.assertEqual(ast.dump(node),
"ClassDef(name='T', keywords=[keyword(arg='a', value=Constant(value=None))], decorator_list=[Name(id='dataclass', ctx=Load())])",
)
self.assertEqual(ast.dump(node, annotate_fields=False),
"ClassDef('T', [], [keyword('a', Constant(None))], [], [Name('dataclass', Load())])",
)
def test_dump_show_empty(self):
def check_node(node, empty, full, **kwargs):
with self.subTest(show_empty=False):
self.assertEqual(
ast.dump(node, show_empty=False, **kwargs),
empty,
)
with self.subTest(show_empty=True):
self.assertEqual(
ast.dump(node, show_empty=True, **kwargs),
full,
)
def check_text(code, empty, full, **kwargs):
check_node(ast.parse(code), empty, full, **kwargs)
check_node(
ast.arguments(),
empty="arguments()",
full="arguments(posonlyargs=[], args=[], kwonlyargs=[], kw_defaults=[], defaults=[])",
)
check_node(
# Corner case: there are no real `Name` instances with `id=''`:
ast.Name(id='', ctx=ast.Load()),
empty="Name(id='', ctx=Load())",
full="Name(id='', ctx=Load())",
)
check_node(
ast.MatchSingleton(value=None),
empty="MatchSingleton(value=None)",
full="MatchSingleton(value=None)",
)
check_node(
ast.Constant(value=None),
empty="Constant(value=None)",
full="Constant(value=None)",
)
check_node(
ast.Constant(value=''),
empty="Constant(value='')",
full="Constant(value='')",
)
check_text(
"def a(b: int = 0, *, c): ...",
empty="Module(body=[FunctionDef(name='a', args=arguments(args=[arg(arg='b', annotation=Name(id='int', ctx=Load()))], kwonlyargs=[arg(arg='c')], kw_defaults=[None], defaults=[Constant(value=0)]), body=[Expr(value=Constant(value=Ellipsis))])])",
full="Module(body=[FunctionDef(name='a', args=arguments(posonlyargs=[], args=[arg(arg='b', annotation=Name(id='int', ctx=Load()))], kwonlyargs=[arg(arg='c')], kw_defaults=[None], defaults=[Constant(value=0)]), body=[Expr(value=Constant(value=Ellipsis))], decorator_list=[], type_params=[])], type_ignores=[])",
)
check_text(
"def a(b: int = 0, *, c): ...",
empty="Module(body=[FunctionDef(name='a', args=arguments(args=[arg(arg='b', annotation=Name(id='int', ctx=Load(), lineno=1, col_offset=9, end_lineno=1, end_col_offset=12), lineno=1, col_offset=6, end_lineno=1, end_col_offset=12)], kwonlyargs=[arg(arg='c', lineno=1, col_offset=21, end_lineno=1, end_col_offset=22)], kw_defaults=[None], defaults=[Constant(value=0, lineno=1, col_offset=15, end_lineno=1, end_col_offset=16)]), body=[Expr(value=Constant(value=Ellipsis, lineno=1, col_offset=25, end_lineno=1, end_col_offset=28), lineno=1, col_offset=25, end_lineno=1, end_col_offset=28)], lineno=1, col_offset=0, end_lineno=1, end_col_offset=28)])",
full="Module(body=[FunctionDef(name='a', args=arguments(posonlyargs=[], args=[arg(arg='b', annotation=Name(id='int', ctx=Load(), lineno=1, col_offset=9, end_lineno=1, end_col_offset=12), lineno=1, col_offset=6, end_lineno=1, end_col_offset=12)], kwonlyargs=[arg(arg='c', lineno=1, col_offset=21, end_lineno=1, end_col_offset=22)], kw_defaults=[None], defaults=[Constant(value=0, lineno=1, col_offset=15, end_lineno=1, end_col_offset=16)]), body=[Expr(value=Constant(value=Ellipsis, lineno=1, col_offset=25, end_lineno=1, end_col_offset=28), lineno=1, col_offset=25, end_lineno=1, end_col_offset=28)], decorator_list=[], type_params=[], lineno=1, col_offset=0, end_lineno=1, end_col_offset=28)], type_ignores=[])",
include_attributes=True,
)
check_text(
'spam(eggs, "and cheese")',
empty="Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load()), args=[Name(id='eggs', ctx=Load()), Constant(value='and cheese')]))])",
full="Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load()), args=[Name(id='eggs', ctx=Load()), Constant(value='and cheese')], keywords=[]))], type_ignores=[])",
)
check_text(
'spam(eggs, text="and cheese")',
empty="Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load()), args=[Name(id='eggs', ctx=Load())], keywords=[keyword(arg='text', value=Constant(value='and cheese'))]))])",
full="Module(body=[Expr(value=Call(func=Name(id='spam', ctx=Load()), args=[Name(id='eggs', ctx=Load())], keywords=[keyword(arg='text', value=Constant(value='and cheese'))]))], type_ignores=[])",
)
check_text(
"import _ast as ast; from module import sub",
empty="Module(body=[Import(names=[alias(name='_ast', asname='ast')]), ImportFrom(module='module', names=[alias(name='sub')], level=0)])",
full="Module(body=[Import(names=[alias(name='_ast', asname='ast')]), ImportFrom(module='module', names=[alias(name='sub')], level=0)], type_ignores=[])",
)
def test_copy_location(self):
src = ast.parse('1 + 1', mode='eval')
src.body.right = ast.copy_location(ast.Constant(2), src.body.right)
self.assertEqual(ast.dump(src, include_attributes=True),
'Expression(body=BinOp(left=Constant(value=1, lineno=1, col_offset=0, '
'end_lineno=1, end_col_offset=1), op=Add(), right=Constant(value=2, '
'lineno=1, col_offset=4, end_lineno=1, end_col_offset=5), lineno=1, '
'col_offset=0, end_lineno=1, end_col_offset=5))'
)
func = ast.Name('spam', ast.Load())
src = ast.Call(col_offset=1, lineno=1, end_lineno=1, end_col_offset=1, func=func)
new = ast.copy_location(src, ast.Call(col_offset=None, lineno=None, func=func))
self.assertIsNone(new.end_lineno)
self.assertIsNone(new.end_col_offset)
self.assertEqual(new.lineno, 1)
self.assertEqual(new.col_offset, 1)
def test_fix_missing_locations(self):
src = ast.parse('write("spam")')
src.body.append(ast.Expr(ast.Call(ast.Name('spam', ast.Load()),
[ast.Constant('eggs')], [])))
self.assertEqual(src, ast.fix_missing_locations(src))
self.maxDiff = None
self.assertEqual(ast.dump(src, include_attributes=True),
"Module(body=[Expr(value=Call(func=Name(id='write', ctx=Load(), "
"lineno=1, col_offset=0, end_lineno=1, end_col_offset=5), "
"args=[Constant(value='spam', lineno=1, col_offset=6, end_lineno=1, "
"end_col_offset=12)], lineno=1, col_offset=0, end_lineno=1, "
"end_col_offset=13), lineno=1, col_offset=0, end_lineno=1, "
"end_col_offset=13), Expr(value=Call(func=Name(id='spam', ctx=Load(), "
"lineno=1, col_offset=0, end_lineno=1, end_col_offset=0), "
"args=[Constant(value='eggs', lineno=1, col_offset=0, end_lineno=1, "
"end_col_offset=0)], lineno=1, col_offset=0, end_lineno=1, "
"end_col_offset=0), lineno=1, col_offset=0, end_lineno=1, end_col_offset=0)])"
)
def test_increment_lineno(self):
src = ast.parse('1 + 1', mode='eval')
self.assertEqual(ast.increment_lineno(src, n=3), src)
self.assertEqual(ast.dump(src, include_attributes=True),
'Expression(body=BinOp(left=Constant(value=1, lineno=4, col_offset=0, '
'end_lineno=4, end_col_offset=1), op=Add(), right=Constant(value=1, '
'lineno=4, col_offset=4, end_lineno=4, end_col_offset=5), lineno=4, '
'col_offset=0, end_lineno=4, end_col_offset=5))'
)
# issue10869: do not increment lineno of root twice
src = ast.parse('1 + 1', mode='eval')
self.assertEqual(ast.increment_lineno(src.body, n=3), src.body)
self.assertEqual(ast.dump(src, include_attributes=True),
'Expression(body=BinOp(left=Constant(value=1, lineno=4, col_offset=0, '
'end_lineno=4, end_col_offset=1), op=Add(), right=Constant(value=1, '
'lineno=4, col_offset=4, end_lineno=4, end_col_offset=5), lineno=4, '
'col_offset=0, end_lineno=4, end_col_offset=5))'
)
src = ast.Call(
func=ast.Name("test", ast.Load()), args=[], keywords=[], lineno=1
)
self.assertEqual(ast.increment_lineno(src).lineno, 2)
self.assertIsNone(ast.increment_lineno(src).end_lineno)
def test_increment_lineno_on_module(self):
src = ast.parse(dedent("""\
a = 1
b = 2 # type: ignore
c = 3
d = 4 # type: ignore@tag
"""), type_comments=True)
ast.increment_lineno(src, n=5)
self.assertEqual(src.type_ignores[0].lineno, 7)
self.assertEqual(src.type_ignores[1].lineno, 9)
self.assertEqual(src.type_ignores[1].tag, '@tag')
def test_iter_fields(self):
node = ast.parse('foo()', mode='eval')
d = dict(ast.iter_fields(node.body))
self.assertEqual(d.pop('func').id, 'foo')
self.assertEqual(d, {'keywords': [], 'args': []})
def test_iter_child_nodes(self):
node = ast.parse("spam(23, 42, eggs='leek')", mode='eval')
self.assertEqual(len(list(ast.iter_child_nodes(node.body))), 4)
iterator = ast.iter_child_nodes(node.body)
self.assertEqual(next(iterator).id, 'spam')
self.assertEqual(next(iterator).value, 23)
self.assertEqual(next(iterator).value, 42)
self.assertEqual(ast.dump(next(iterator)),
"keyword(arg='eggs', value=Constant(value='leek'))"
)
def test_get_docstring(self):
node = ast.parse('"""line one\n line two"""')
self.assertEqual(ast.get_docstring(node),
'line one\nline two')
node = ast.parse('class foo:\n """line one\n line two"""')
self.assertEqual(ast.get_docstring(node.body[0]),
'line one\nline two')
node = ast.parse('def foo():\n """line one\n line two"""')
self.assertEqual(ast.get_docstring(node.body[0]),
'line one\nline two')
node = ast.parse('async def foo():\n """spam\n ham"""')
self.assertEqual(ast.get_docstring(node.body[0]), 'spam\nham')
node = ast.parse('async def foo():\n """spam\n ham"""')
self.assertEqual(ast.get_docstring(node.body[0], clean=False), 'spam\n ham')
node = ast.parse('x')
self.assertRaises(TypeError, ast.get_docstring, node.body[0])
def test_get_docstring_none(self):
self.assertIsNone(ast.get_docstring(ast.parse('')))
node = ast.parse('x = "not docstring"')
self.assertIsNone(ast.get_docstring(node))
node = ast.parse('def foo():\n pass')
self.assertIsNone(ast.get_docstring(node))
node = ast.parse('class foo:\n pass')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('class foo:\n x = "not docstring"')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('class foo:\n def bar(self): pass')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('def foo():\n pass')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('def foo():\n x = "not docstring"')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('async def foo():\n pass')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('async def foo():\n x = "not docstring"')
self.assertIsNone(ast.get_docstring(node.body[0]))
node = ast.parse('async def foo():\n 42')
self.assertIsNone(ast.get_docstring(node.body[0]))
def test_multi_line_docstring_col_offset_and_lineno_issue16806(self):
node = ast.parse(
'"""line one\nline two"""\n\n'
'def foo():\n """line one\n line two"""\n\n'
' def bar():\n """line one\n line two"""\n'
' """line one\n line two"""\n'
'"""line one\nline two"""\n\n'
)
self.assertEqual(node.body[0].col_offset, 0)
self.assertEqual(node.body[0].lineno, 1)
self.assertEqual(node.body[1].body[0].col_offset, 2)
self.assertEqual(node.body[1].body[0].lineno, 5)
self.assertEqual(node.body[1].body[1].body[0].col_offset, 4)
self.assertEqual(node.body[1].body[1].body[0].lineno, 9)
self.assertEqual(node.body[1].body[2].col_offset, 2)
self.assertEqual(node.body[1].body[2].lineno, 11)
self.assertEqual(node.body[2].col_offset, 0)
self.assertEqual(node.body[2].lineno, 13)
def test_elif_stmt_start_position(self):
node = ast.parse('if a:\n pass\nelif b:\n pass\n')
elif_stmt = node.body[0].orelse[0]
self.assertEqual(elif_stmt.lineno, 3)
self.assertEqual(elif_stmt.col_offset, 0)
def test_elif_stmt_start_position_with_else(self):
node = ast.parse('if a:\n pass\nelif b:\n pass\nelse:\n pass\n')
elif_stmt = node.body[0].orelse[0]
self.assertEqual(elif_stmt.lineno, 3)
self.assertEqual(elif_stmt.col_offset, 0)
def test_starred_expr_end_position_within_call(self):
node = ast.parse('f(*[0, 1])')
starred_expr = node.body[0].value.args[0]
self.assertEqual(starred_expr.end_lineno, 1)
self.assertEqual(starred_expr.end_col_offset, 9)
def test_literal_eval(self):
self.assertEqual(ast.literal_eval('[1, 2, 3]'), [1, 2, 3])
self.assertEqual(ast.literal_eval('{"foo": 42}'), {"foo": 42})
self.assertEqual(ast.literal_eval('(True, False, None)'), (True, False, None))
self.assertEqual(ast.literal_eval('{1, 2, 3}'), {1, 2, 3})
self.assertEqual(ast.literal_eval('b"hi"'), b"hi")
self.assertEqual(ast.literal_eval('set()'), set())
self.assertRaises(ValueError, ast.literal_eval, 'foo()')
self.assertEqual(ast.literal_eval('6'), 6)
self.assertEqual(ast.literal_eval('+6'), 6)
self.assertEqual(ast.literal_eval('-6'), -6)
self.assertEqual(ast.literal_eval('3.25'), 3.25)
self.assertEqual(ast.literal_eval('+3.25'), 3.25)
self.assertEqual(ast.literal_eval('-3.25'), -3.25)
self.assertEqual(repr(ast.literal_eval('-0.0')), '-0.0')
self.assertRaises(ValueError, ast.literal_eval, '++6')
self.assertRaises(ValueError, ast.literal_eval, '+True')
self.assertRaises(ValueError, ast.literal_eval, '2+3')
def test_literal_eval_str_int_limit(self):
with support.adjust_int_max_str_digits(4000):
ast.literal_eval('3'*4000) # no error
with self.assertRaises(SyntaxError) as err_ctx:
ast.literal_eval('3'*4001)
self.assertIn('Exceeds the limit ', str(err_ctx.exception))
self.assertIn(' Consider hexadecimal ', str(err_ctx.exception))
def test_literal_eval_complex(self):
# Issue #4907
self.assertEqual(ast.literal_eval('6j'), 6j)
self.assertEqual(ast.literal_eval('-6j'), -6j)
self.assertEqual(ast.literal_eval('6.75j'), 6.75j)
self.assertEqual(ast.literal_eval('-6.75j'), -6.75j)
self.assertEqual(ast.literal_eval('3+6j'), 3+6j)
self.assertEqual(ast.literal_eval('-3+6j'), -3+6j)
self.assertEqual(ast.literal_eval('3-6j'), 3-6j)
self.assertEqual(ast.literal_eval('-3-6j'), -3-6j)
self.assertEqual(ast.literal_eval('3.25+6.75j'), 3.25+6.75j)
self.assertEqual(ast.literal_eval('-3.25+6.75j'), -3.25+6.75j)
self.assertEqual(ast.literal_eval('3.25-6.75j'), 3.25-6.75j)
self.assertEqual(ast.literal_eval('-3.25-6.75j'), -3.25-6.75j)
self.assertEqual(ast.literal_eval('(3+6j)'), 3+6j)
self.assertRaises(ValueError, ast.literal_eval, '-6j+3')
self.assertRaises(ValueError, ast.literal_eval, '-6j+3j')
self.assertRaises(ValueError, ast.literal_eval, '3+-6j')
self.assertRaises(ValueError, ast.literal_eval, '3+(0+6j)')
self.assertRaises(ValueError, ast.literal_eval, '-(3+6j)')
def test_literal_eval_malformed_dict_nodes(self):
malformed = ast.Dict(keys=[ast.Constant(1), ast.Constant(2)], values=[ast.Constant(3)])
self.assertRaises(ValueError, ast.literal_eval, malformed)
malformed = ast.Dict(keys=[ast.Constant(1)], values=[ast.Constant(2), ast.Constant(3)])
self.assertRaises(ValueError, ast.literal_eval, malformed)
def test_literal_eval_trailing_ws(self):
self.assertEqual(ast.literal_eval(" -1"), -1)
self.assertEqual(ast.literal_eval("\t\t-1"), -1)
self.assertEqual(ast.literal_eval(" \t -1"), -1)
self.assertRaises(IndentationError, ast.literal_eval, "\n -1")
def test_literal_eval_malformed_lineno(self):
msg = r'malformed node or string on line 3:'
with self.assertRaisesRegex(ValueError, msg):
ast.literal_eval("{'a': 1,\n'b':2,\n'c':++3,\n'd':4}")
node = ast.UnaryOp(
ast.UAdd(), ast.UnaryOp(ast.UAdd(), ast.Constant(6)))
self.assertIsNone(getattr(node, 'lineno', None))
msg = r'malformed node or string:'
with self.assertRaisesRegex(ValueError, msg):
ast.literal_eval(node)
def test_literal_eval_syntax_errors(self):
with self.assertRaisesRegex(SyntaxError, "unexpected indent"):
ast.literal_eval(r'''
\
(\
\ ''')
def test_bad_integer(self):
# issue13436: Bad error message with invalid numeric values
body = [ast.ImportFrom(module='time',
names=[ast.alias(name='sleep')],
level=None,
lineno=None, col_offset=None)]
mod = ast.Module(body, [])
with self.assertRaises(ValueError) as cm:
compile(mod, 'test', 'exec')
self.assertIn("invalid integer value: None", str(cm.exception))
def test_level_as_none(self):
body = [ast.ImportFrom(module='time',
names=[ast.alias(name='sleep',
lineno=0, col_offset=0)],
level=None,
lineno=0, col_offset=0)]
mod = ast.Module(body, [])
code = compile(mod, 'test', 'exec')
ns = {}
exec(code, ns)
self.assertIn('sleep', ns)
def test_recursion_direct(self):
e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))
e.operand = e
with self.assertRaises(RecursionError):
with support.infinite_recursion():
compile(ast.Expression(e), "<test>", "eval")
def test_recursion_indirect(self):
e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))
f = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1))
e.operand = f
f.operand = e
with self.assertRaises(RecursionError):
with support.infinite_recursion():
compile(ast.Expression(e), "<test>", "eval")
class ASTValidatorTests(unittest.TestCase):
def mod(self, mod, msg=None, mode="exec", *, exc=ValueError):
mod.lineno = mod.col_offset = 0
ast.fix_missing_locations(mod)
if msg is None:
compile(mod, "<test>", mode)
else:
with self.assertRaises(exc) as cm:
compile(mod, "<test>", mode)
self.assertIn(msg, str(cm.exception))
def expr(self, node, msg=None, *, exc=ValueError):
mod = ast.Module([ast.Expr(node)], [])
self.mod(mod, msg, exc=exc)
def stmt(self, stmt, msg=None):
mod = ast.Module([stmt], [])
self.mod(mod, msg)
def test_module(self):
m = ast.Interactive([ast.Expr(ast.Name("x", ast.Store()))])
self.mod(m, "must have Load context", "single")
m = ast.Expression(ast.Name("x", ast.Store()))
self.mod(m, "must have Load context", "eval")
def _check_arguments(self, fac, check):
def arguments(args=None, posonlyargs=None, vararg=None,
kwonlyargs=None, kwarg=None,
defaults=None, kw_defaults=None):
if args is None:
args = []
if posonlyargs is None:
posonlyargs = []
if kwonlyargs is None:
kwonlyargs = []
if defaults is None:
defaults = []
if kw_defaults is None:
kw_defaults = []
args = ast.arguments(args, posonlyargs, vararg, kwonlyargs,
kw_defaults, kwarg, defaults)
return fac(args)
args = [ast.arg("x", ast.Name("x", ast.Store()))]
check(arguments(args=args), "must have Load context")
check(arguments(posonlyargs=args), "must have Load context")
check(arguments(kwonlyargs=args), "must have Load context")
check(arguments(defaults=[ast.Constant(3)]),
"more positional defaults than args")
check(arguments(kw_defaults=[ast.Constant(4)]),
"length of kwonlyargs is not the same as kw_defaults")
args = [ast.arg("x", ast.Name("x", ast.Load()))]
check(arguments(args=args, defaults=[ast.Name("x", ast.Store())]),
"must have Load context")
args = [ast.arg("a", ast.Name("x", ast.Load())),
ast.arg("b", ast.Name("y", ast.Load()))]
check(arguments(kwonlyargs=args,
kw_defaults=[None, ast.Name("x", ast.Store())]),
"must have Load context")
def test_funcdef(self):
a = ast.arguments([], [], None, [], [], None, [])
f = ast.FunctionDef("x", a, [], [], None, None, [])
self.stmt(f, "empty body on FunctionDef")
f = ast.FunctionDef("x", a, [ast.Pass()], [ast.Name("x", ast.Store())], None, None, [])
self.stmt(f, "must have Load context")
f = ast.FunctionDef("x", a, [ast.Pass()], [],
ast.Name("x", ast.Store()), None, [])
self.stmt(f, "must have Load context")
f = ast.FunctionDef("x", ast.arguments(), [ast.Pass()])
self.stmt(f)
def fac(args):
return ast.FunctionDef("x", args, [ast.Pass()], [], None, None, [])
self._check_arguments(fac, self.stmt)
def test_funcdef_pattern_matching(self):
# gh-104799: New fields on FunctionDef should be added at the end
def matcher(node):
match node:
case ast.FunctionDef("foo", ast.arguments(args=[ast.arg("bar")]),
[ast.Pass()],
[ast.Name("capybara", ast.Load())],
ast.Name("pacarana", ast.Load())):
return True
case _:
return False
code = """
@capybara
def foo(bar) -> pacarana:
pass
"""
source = ast.parse(textwrap.dedent(code))
funcdef = source.body[0]
self.assertIsInstance(funcdef, ast.FunctionDef)
self.assertTrue(matcher(funcdef))
def test_classdef(self):
def cls(bases=None, keywords=None, body=None, decorator_list=None, type_params=None):
if bases is None:
bases = []
if keywords is None:
keywords = []
if body is None:
body = [ast.Pass()]
if decorator_list is None:
decorator_list = []
if type_params is None:
type_params = []
return ast.ClassDef("myclass", bases, keywords,
body, decorator_list, type_params)
self.stmt(cls(bases=[ast.Name("x", ast.Store())]),
"must have Load context")
self.stmt(cls(keywords=[ast.keyword("x", ast.Name("x", ast.Store()))]),
"must have Load context")
self.stmt(cls(body=[]), "empty body on ClassDef")
self.stmt(cls(body=[None]), "None disallowed")
self.stmt(cls(decorator_list=[ast.Name("x", ast.Store())]),
"must have Load context")
def test_delete(self):
self.stmt(ast.Delete([]), "empty targets on Delete")
self.stmt(ast.Delete([None]), "None disallowed")
self.stmt(ast.Delete([ast.Name("x", ast.Load())]),
"must have Del context")
def test_assign(self):
self.stmt(ast.Assign([], ast.Constant(3)), "empty targets on Assign")
self.stmt(ast.Assign([None], ast.Constant(3)), "None disallowed")
self.stmt(ast.Assign([ast.Name("x", ast.Load())], ast.Constant(3)),
"must have Store context")
self.stmt(ast.Assign([ast.Name("x", ast.Store())],
ast.Name("y", ast.Store())),
"must have Load context")
def test_augassign(self):
aug = ast.AugAssign(ast.Name("x", ast.Load()), ast.Add(),
ast.Name("y", ast.Load()))
self.stmt(aug, "must have Store context")
aug = ast.AugAssign(ast.Name("x", ast.Store()), ast.Add(),
ast.Name("y", ast.Store()))
self.stmt(aug, "must have Load context")
def test_for(self):
x = ast.Name("x", ast.Store())
y = ast.Name("y", ast.Load())
p = ast.Pass()
self.stmt(ast.For(x, y, [], []), "empty body on For")
self.stmt(ast.For(ast.Name("x", ast.Load()), y, [p], []),
"must have Store context")
self.stmt(ast.For(x, ast.Name("y", ast.Store()), [p], []),
"must have Load context")
e = ast.Expr(ast.Name("x", ast.Store()))
self.stmt(ast.For(x, y, [e], []), "must have Load context")
self.stmt(ast.For(x, y, [p], [e]), "must have Load context")
def test_while(self):
self.stmt(ast.While(ast.Constant(3), [], []), "empty body on While")
self.stmt(ast.While(ast.Name("x", ast.Store()), [ast.Pass()], []),
"must have Load context")
self.stmt(ast.While(ast.Constant(3), [ast.Pass()],
[ast.Expr(ast.Name("x", ast.Store()))]),
"must have Load context")
def test_if(self):
self.stmt(ast.If(ast.Constant(3), [], []), "empty body on If")
i = ast.If(ast.Name("x", ast.Store()), [ast.Pass()], [])
self.stmt(i, "must have Load context")
i = ast.If(ast.Constant(3), [ast.Expr(ast.Name("x", ast.Store()))], [])
self.stmt(i, "must have Load context")
i = ast.If(ast.Constant(3), [ast.Pass()],
[ast.Expr(ast.Name("x", ast.Store()))])
self.stmt(i, "must have Load context")
def test_with(self):
p = ast.Pass()
self.stmt(ast.With([], [p]), "empty items on With")
i = ast.withitem(ast.Constant(3), None)
self.stmt(ast.With([i], []), "empty body on With")
i = ast.withitem(ast.Name("x", ast.Store()), None)
self.stmt(ast.With([i], [p]), "must have Load context")
i = ast.withitem(ast.Constant(3), ast.Name("x", ast.Load()))
self.stmt(ast.With([i], [p]), "must have Store context")
def test_raise(self):
r = ast.Raise(None, ast.Constant(3))
self.stmt(r, "Raise with cause but no exception")
r = ast.Raise(ast.Name("x", ast.Store()), None)
self.stmt(r, "must have Load context")
r = ast.Raise(ast.Constant(4), ast.Name("x", ast.Store()))
self.stmt(r, "must have Load context")
def test_try(self):
p = ast.Pass()
t = ast.Try([], [], [], [p])
self.stmt(t, "empty body on Try")
t = ast.Try([ast.Expr(ast.Name("x", ast.Store()))], [], [], [p])
self.stmt(t, "must have Load context")
t = ast.Try([p], [], [], [])
self.stmt(t, "Try has neither except handlers nor finalbody")
t = ast.Try([p], [], [p], [p])
self.stmt(t, "Try has orelse but no except handlers")
t = ast.Try([p], [ast.ExceptHandler(None, "x", [])], [], [])
self.stmt(t, "empty body on ExceptHandler")
e = [ast.ExceptHandler(ast.Name("x", ast.Store()), "y", [p])]
self.stmt(ast.Try([p], e, [], []), "must have Load context")
e = [ast.ExceptHandler(None, "x", [p])]
t = ast.Try([p], e, [ast.Expr(ast.Name("x", ast.Store()))], [p])
self.stmt(t, "must have Load context")
t = ast.Try([p], e, [p], [ast.Expr(ast.Name("x", ast.Store()))])
self.stmt(t, "must have Load context")
def test_try_star(self):
p = ast.Pass()
t = ast.TryStar([], [], [], [p])
self.stmt(t, "empty body on TryStar")
t = ast.TryStar([ast.Expr(ast.Name("x", ast.Store()))], [], [], [p])
self.stmt(t, "must have Load context")
t = ast.TryStar([p], [], [], [])
self.stmt(t, "TryStar has neither except handlers nor finalbody")
t = ast.TryStar([p], [], [p], [p])
self.stmt(t, "TryStar has orelse but no except handlers")
t = ast.TryStar([p], [ast.ExceptHandler(None, "x", [])], [], [])
self.stmt(t, "empty body on ExceptHandler")
e = [ast.ExceptHandler(ast.Name("x", ast.Store()), "y", [p])]
self.stmt(ast.TryStar([p], e, [], []), "must have Load context")
e = [ast.ExceptHandler(None, "x", [p])]
t = ast.TryStar([p], e, [ast.Expr(ast.Name("x", ast.Store()))], [p])
self.stmt(t, "must have Load context")
t = ast.TryStar([p], e, [p], [ast.Expr(ast.Name("x", ast.Store()))])
self.stmt(t, "must have Load context")
def test_assert(self):
self.stmt(ast.Assert(ast.Name("x", ast.Store()), None),
"must have Load context")
assrt = ast.Assert(ast.Name("x", ast.Load()),
ast.Name("y", ast.Store()))
self.stmt(assrt, "must have Load context")
def test_import(self):
self.stmt(ast.Import([]), "empty names on Import")
def test_importfrom(self):
imp = ast.ImportFrom(None, [ast.alias("x", None)], -42)
self.stmt(imp, "Negative ImportFrom level")
self.stmt(ast.ImportFrom(None, [], 0), "empty names on ImportFrom")
def test_global(self):
self.stmt(ast.Global([]), "empty names on Global")
def test_nonlocal(self):
self.stmt(ast.Nonlocal([]), "empty names on Nonlocal")
def test_expr(self):
e = ast.Expr(ast.Name("x", ast.Store()))
self.stmt(e, "must have Load context")
def test_boolop(self):
b = ast.BoolOp(ast.And(), [])
self.expr(b, "less than 2 values")
b = ast.BoolOp(ast.And(), [ast.Constant(3)])
self.expr(b, "less than 2 values")
b = ast.BoolOp(ast.And(), [ast.Constant(4), None])
self.expr(b, "None disallowed")
b = ast.BoolOp(ast.And(), [ast.Constant(4), ast.Name("x", ast.Store())])
self.expr(b, "must have Load context")
def test_unaryop(self):
u = ast.UnaryOp(ast.Not(), ast.Name("x", ast.Store()))
self.expr(u, "must have Load context")
def test_lambda(self):
a = ast.arguments([], [], None, [], [], None, [])
self.expr(ast.Lambda(a, ast.Name("x", ast.Store())),
"must have Load context")
def fac(args):
return ast.Lambda(args, ast.Name("x", ast.Load()))
self._check_arguments(fac, self.expr)
def test_ifexp(self):
l = ast.Name("x", ast.Load())
s = ast.Name("y", ast.Store())
for args in (s, l, l), (l, s, l), (l, l, s):
self.expr(ast.IfExp(*args), "must have Load context")
def test_dict(self):
d = ast.Dict([], [ast.Name("x", ast.Load())])
self.expr(d, "same number of keys as values")
d = ast.Dict([ast.Name("x", ast.Load())], [None])
self.expr(d, "None disallowed")
def test_set(self):
self.expr(ast.Set([None]), "None disallowed")
s = ast.Set([ast.Name("x", ast.Store())])
self.expr(s, "must have Load context")
def _check_comprehension(self, fac):
self.expr(fac([]), "comprehension with no generators")
g = ast.comprehension(ast.Name("x", ast.Load()),
ast.Name("x", ast.Load()), [], 0)
self.expr(fac([g]), "must have Store context")
g = ast.comprehension(ast.Name("x", ast.Store()),
ast.Name("x", ast.Store()), [], 0)
self.expr(fac([g]), "must have Load context")
x = ast.Name("x", ast.Store())
y = ast.Name("y", ast.Load())
g = ast.comprehension(x, y, [None], 0)
self.expr(fac([g]), "None disallowed")
g = ast.comprehension(x, y, [ast.Name("x", ast.Store())], 0)
self.expr(fac([g]), "must have Load context")
def _simple_comp(self, fac):
g = ast.comprehension(ast.Name("x", ast.Store()),
ast.Name("x", ast.Load()), [], 0)
self.expr(fac(ast.Name("x", ast.Store()), [g]),
"must have Load context")
def wrap(gens):
return fac(ast.Name("x", ast.Store()), gens)
self._check_comprehension(wrap)
def test_listcomp(self):
self._simple_comp(ast.ListComp)
def test_setcomp(self):
self._simple_comp(ast.SetComp)
def test_generatorexp(self):
self._simple_comp(ast.GeneratorExp)
def test_dictcomp(self):
g = ast.comprehension(ast.Name("y", ast.Store()),
ast.Name("p", ast.Load()), [], 0)
c = ast.DictComp(ast.Name("x", ast.Store()),
ast.Name("y", ast.Load()), [g])
self.expr(c, "must have Load context")
c = ast.DictComp(ast.Name("x", ast.Load()),
ast.Name("y", ast.Store()), [g])
self.expr(c, "must have Load context")
def factory(comps):
k = ast.Name("x", ast.Load())
v = ast.Name("y", ast.Load())
return ast.DictComp(k, v, comps)
self._check_comprehension(factory)
def test_yield(self):
self.expr(ast.Yield(ast.Name("x", ast.Store())), "must have Load")
self.expr(ast.YieldFrom(ast.Name("x", ast.Store())), "must have Load")
def test_compare(self):
left = ast.Name("x", ast.Load())
comp = ast.Compare(left, [ast.In()], [])
self.expr(comp, "no comparators")
comp = ast.Compare(left, [ast.In()], [ast.Constant(4), ast.Constant(5)])
self.expr(comp, "different number of comparators and operands")
comp = ast.Compare(ast.Constant("blah"), [ast.In()], [left])
self.expr(comp)
comp = ast.Compare(left, [ast.In()], [ast.Constant("blah")])
self.expr(comp)
def test_call(self):
func = ast.Name("x", ast.Load())
args = [ast.Name("y", ast.Load())]
keywords = [ast.keyword("w", ast.Name("z", ast.Load()))]
call = ast.Call(ast.Name("x", ast.Store()), args, keywords)
self.expr(call, "must have Load context")
call = ast.Call(func, [None], keywords)
self.expr(call, "None disallowed")
bad_keywords = [ast.keyword("w", ast.Name("z", ast.Store()))]
call = ast.Call(func, args, bad_keywords)
self.expr(call, "must have Load context")
def test_attribute(self):
attr = ast.Attribute(ast.Name("x", ast.Store()), "y", ast.Load())
self.expr(attr, "must have Load context")
def test_subscript(self):
sub = ast.Subscript(ast.Name("x", ast.Store()), ast.Constant(3),
ast.Load())
self.expr(sub, "must have Load context")
x = ast.Name("x", ast.Load())
sub = ast.Subscript(x, ast.Name("y", ast.Store()),
ast.Load())
self.expr(sub, "must have Load context")
s = ast.Name("x", ast.Store())
for args in (s, None, None), (None, s, None), (None, None, s):
sl = ast.Slice(*args)
self.expr(ast.Subscript(x, sl, ast.Load()),
"must have Load context")
sl = ast.Tuple([], ast.Load())
self.expr(ast.Subscript(x, sl, ast.Load()))
sl = ast.Tuple([s], ast.Load())
self.expr(ast.Subscript(x, sl, ast.Load()), "must have Load context")
def test_starred(self):
left = ast.List([ast.Starred(ast.Name("x", ast.Load()), ast.Store())],
ast.Store())
assign = ast.Assign([left], ast.Constant(4))
self.stmt(assign, "must have Store context")
def _sequence(self, fac):
self.expr(fac([None], ast.Load()), "None disallowed")
self.expr(fac([ast.Name("x", ast.Store())], ast.Load()),
"must have Load context")
def test_list(self):
self._sequence(ast.List)
def test_tuple(self):
self._sequence(ast.Tuple)
@support.requires_resource('cpu')
def test_stdlib_validates(self):
for module in STDLIB_FILES:
with self.subTest(module):
fn = os.path.join(STDLIB, module)
with open(fn, "r", encoding="utf-8") as fp:
source = fp.read()
mod = ast.parse(source, fn)
compile(mod, fn, "exec")
mod2 = ast.parse(source, fn)
self.assertTrue(ast.compare(mod, mod2))
constant_1 = ast.Constant(1)
pattern_1 = ast.MatchValue(constant_1)
constant_x = ast.Constant('x')
pattern_x = ast.MatchValue(constant_x)
constant_true = ast.Constant(True)
pattern_true = ast.MatchSingleton(True)
name_carter = ast.Name('carter', ast.Load())
_MATCH_PATTERNS = [
ast.MatchValue(
ast.Attribute(
ast.Attribute(
ast.Name('x', ast.Store()),
'y', ast.Load()
),
'z', ast.Load()
)
),
ast.MatchValue(
ast.Attribute(
ast.Attribute(
ast.Name('x', ast.Load()),
'y', ast.Store()
),
'z', ast.Load()
)
),
ast.MatchValue(
ast.Constant(...)
),
ast.MatchValue(
ast.Constant(True)
),
ast.MatchValue(
ast.Constant((1,2,3))
),
ast.MatchSingleton('string'),
ast.MatchSequence([
ast.MatchSingleton('string')
]),
ast.MatchSequence(
[
ast.MatchSequence(
[
ast.MatchSingleton('string')
]
)
]
),
ast.MatchMapping(
[constant_1, constant_true],
[pattern_x]
),
ast.MatchMapping(
[constant_true, constant_1],
[pattern_x, pattern_1],
rest='True'
),
ast.MatchMapping(
[constant_true, ast.Starred(ast.Name('lol', ast.Load()), ast.Load())],
[pattern_x, pattern_1],
rest='legit'
),
ast.MatchClass(
ast.Attribute(
ast.Attribute(
constant_x,
'y', ast.Load()),
'z', ast.Load()),
patterns=[], kwd_attrs=[], kwd_patterns=[]
),
ast.MatchClass(
name_carter,
patterns=[],
kwd_attrs=['True'],
kwd_patterns=[pattern_1]
),
ast.MatchClass(
name_carter,
patterns=[],
kwd_attrs=[],
kwd_patterns=[pattern_1]
),
ast.MatchClass(
name_carter,
patterns=[ast.MatchSingleton('string')],
kwd_attrs=[],
kwd_patterns=[]
),
ast.MatchClass(
name_carter,
patterns=[ast.MatchStar()],
kwd_attrs=[],
kwd_patterns=[]
),
ast.MatchClass(
name_carter,
patterns=[],
kwd_attrs=[],
kwd_patterns=[ast.MatchStar()]
),
ast.MatchClass(
constant_true, # invalid name
patterns=[],
kwd_attrs=['True'],
kwd_patterns=[pattern_1]
),
ast.MatchSequence(
[
ast.MatchStar("True")
]
),
ast.MatchAs(
name='False'
),
ast.MatchOr(
[]
),
ast.MatchOr(
[pattern_1]
),
ast.MatchOr(
[pattern_1, pattern_x, ast.MatchSingleton('xxx')]
),
ast.MatchAs(name="_"),
ast.MatchStar(name="x"),
ast.MatchSequence([ast.MatchStar("_")]),
ast.MatchMapping([], [], rest="_"),
]
def test_match_validation_pattern(self):
name_x = ast.Name('x', ast.Load())
for pattern in self._MATCH_PATTERNS:
with self.subTest(ast.dump(pattern, indent=4)):
node = ast.Match(
subject=name_x,
cases = [
ast.match_case(
pattern=pattern,
body = [ast.Pass()]
)
]
)
node = ast.fix_missing_locations(node)
module = ast.Module([node], [])
with self.assertRaises(ValueError):
compile(module, "<test>", "exec")
class ConstantTests(unittest.TestCase):
"""Tests on the ast.Constant node type."""
def compile_constant(self, value):
tree = ast.parse("x = 123")
node = tree.body[0].value
new_node = ast.Constant(value=value)
ast.copy_location(new_node, node)
tree.body[0].value = new_node
code = compile(tree, "<string>", "exec")
ns = {}
exec(code, ns)
return ns['x']
def test_validation(self):
with self.assertRaises(TypeError) as cm:
self.compile_constant([1, 2, 3])
self.assertEqual(str(cm.exception),
"got an invalid type in Constant: list")
def test_singletons(self):
for const in (None, False, True, Ellipsis, b'', frozenset()):
with self.subTest(const=const):
value = self.compile_constant(const)
self.assertIs(value, const)
def test_values(self):
nested_tuple = (1,)
nested_frozenset = frozenset({1})
for level in range(3):
nested_tuple = (nested_tuple, 2)
nested_frozenset = frozenset({nested_frozenset, 2})
values = (123, 123.0, 123j,
"unicode", b'bytes',
tuple("tuple"), frozenset("frozenset"),
nested_tuple, nested_frozenset)
for value in values:
with self.subTest(value=value):
result = self.compile_constant(value)
self.assertEqual(result, value)
def test_assign_to_constant(self):
tree = ast.parse("x = 1")
target = tree.body[0].targets[0]
new_target = ast.Constant(value=1)
ast.copy_location(new_target, target)
tree.body[0].targets[0] = new_target
with self.assertRaises(ValueError) as cm:
compile(tree, "string", "exec")
self.assertEqual(str(cm.exception),
"expression which can't be assigned "
"to in Store context")
def test_get_docstring(self):
tree = ast.parse("'docstring'\nx = 1")
self.assertEqual(ast.get_docstring(tree), 'docstring')
def get_load_const(self, tree):
# Compile to bytecode, disassemble and get parameter of LOAD_CONST
# instructions
co = compile(tree, '<string>', 'exec')
consts = []
for instr in dis.get_instructions(co):
if instr.opname == 'LOAD_CONST' or instr.opname == 'RETURN_CONST':
consts.append(instr.argval)
return consts
@support.cpython_only
def test_load_const(self):
consts = [None,
True, False,
124,
2.0,
3j,
"unicode",
b'bytes',
(1, 2, 3)]
code = '\n'.join(['x={!r}'.format(const) for const in consts])
code += '\nx = ...'
consts.extend((Ellipsis, None))
tree = ast.parse(code)
self.assertEqual(self.get_load_const(tree),
consts)
# Replace expression nodes with constants
for assign, const in zip(tree.body, consts):
assert isinstance(assign, ast.Assign), ast.dump(assign)
new_node = ast.Constant(value=const)
ast.copy_location(new_node, assign.value)
assign.value = new_node
self.assertEqual(self.get_load_const(tree),
consts)
def test_literal_eval(self):
tree = ast.parse("1 + 2")
binop = tree.body[0].value
new_left = ast.Constant(value=10)
ast.copy_location(new_left, binop.left)
binop.left = new_left
new_right = ast.Constant(value=20j)
ast.copy_location(new_right, binop.right)
binop.right = new_right
self.assertEqual(ast.literal_eval(binop), 10+20j)
def test_string_kind(self):
c = ast.parse('"x"', mode='eval').body
self.assertEqual(c.value, "x")
self.assertEqual(c.kind, None)
c = ast.parse('u"x"', mode='eval').body
self.assertEqual(c.value, "x")
self.assertEqual(c.kind, "u")
c = ast.parse('r"x"', mode='eval').body
self.assertEqual(c.value, "x")
self.assertEqual(c.kind, None)
c = ast.parse('b"x"', mode='eval').body
self.assertEqual(c.value, b"x")
self.assertEqual(c.kind, None)
class EndPositionTests(unittest.TestCase):
"""Tests for end position of AST nodes.
Testing end positions of nodes requires a bit of extra care
because of how LL parsers work.
"""
def _check_end_pos(self, ast_node, end_lineno, end_col_offset):
self.assertEqual(ast_node.end_lineno, end_lineno)
self.assertEqual(ast_node.end_col_offset, end_col_offset)
def _check_content(self, source, ast_node, content):
self.assertEqual(ast.get_source_segment(source, ast_node), content)
def _parse_value(self, s):
# Use duck-typing to support both single expression
# and a right hand side of an assignment statement.
return ast.parse(s).body[0].value
def test_lambda(self):
s = 'lambda x, *y: None'
lam = self._parse_value(s)
self._check_content(s, lam.body, 'None')
self._check_content(s, lam.args.args[0], 'x')
self._check_content(s, lam.args.vararg, 'y')
def test_func_def(self):
s = dedent('''
def func(x: int,
*args: str,
z: float = 0,
**kwargs: Any) -> bool:
return True
''').strip()
fdef = ast.parse(s).body[0]
self._check_end_pos(fdef, 5, 15)
self._check_content(s, fdef.body[0], 'return True')
self._check_content(s, fdef.args.args[0], 'x: int')
self._check_content(s, fdef.args.args[0].annotation, 'int')
self._check_content(s, fdef.args.kwarg, 'kwargs: Any')
self._check_content(s, fdef.args.kwarg.annotation, 'Any')
def test_call(self):
s = 'func(x, y=2, **kw)'
call = self._parse_value(s)
self._check_content(s, call.func, 'func')
self._check_content(s, call.keywords[0].value, '2')
self._check_content(s, call.keywords[1].value, 'kw')
def test_call_noargs(self):
s = 'x[0]()'
call = self._parse_value(s)
self._check_content(s, call.func, 'x[0]')
self._check_end_pos(call, 1, 6)
def test_class_def(self):
s = dedent('''
class C(A, B):
x: int = 0
''').strip()
cdef = ast.parse(s).body[0]
self._check_end_pos(cdef, 2, 14)
self._check_content(s, cdef.bases[1], 'B')
self._check_content(s, cdef.body[0], 'x: int = 0')
def test_class_kw(self):
s = 'class S(metaclass=abc.ABCMeta): pass'
cdef = ast.parse(s).body[0]
self._check_content(s, cdef.keywords[0].value, 'abc.ABCMeta')
def test_multi_line_str(self):
s = dedent('''
x = """Some multi-line text.
It goes on starting from same indent."""
''').strip()
assign = ast.parse(s).body[0]
self._check_end_pos(assign, 3, 40)
self._check_end_pos(assign.value, 3, 40)
def test_continued_str(self):
s = dedent('''
x = "first part" \\
"second part"
''').strip()
assign = ast.parse(s).body[0]
self._check_end_pos(assign, 2, 13)
self._check_end_pos(assign.value, 2, 13)
def test_suites(self):
# We intentionally put these into the same string to check
# that empty lines are not part of the suite.
s = dedent('''
while True:
pass
if one():
x = None
elif other():
y = None
else:
z = None
for x, y in stuff:
assert True
try:
raise RuntimeError
except TypeError as e:
pass
pass
''').strip()
mod = ast.parse(s)
while_loop = mod.body[0]
if_stmt = mod.body[1]
for_loop = mod.body[2]
try_stmt = mod.body[3]
pass_stmt = mod.body[4]
self._check_end_pos(while_loop, 2, 8)
self._check_end_pos(if_stmt, 9, 12)
self._check_end_pos(for_loop, 12, 15)
self._check_end_pos(try_stmt, 17, 8)
self._check_end_pos(pass_stmt, 19, 4)
self._check_content(s, while_loop.test, 'True')
self._check_content(s, if_stmt.body[0], 'x = None')
self._check_content(s, if_stmt.orelse[0].test, 'other()')
self._check_content(s, for_loop.target, 'x, y')
self._check_content(s, try_stmt.body[0], 'raise RuntimeError')
self._check_content(s, try_stmt.handlers[0].type, 'TypeError')
def test_fstring(self):
s = 'x = f"abc {x + y} abc"'
fstr = self._parse_value(s)
binop = fstr.values[1].value
self._check_content(s, binop, 'x + y')
def test_fstring_multi_line(self):
s = dedent('''
f"""Some multi-line text.
{
arg_one
+
arg_two
}
It goes on..."""
''').strip()
fstr = self._parse_value(s)
binop = fstr.values[1].value
self._check_end_pos(binop, 5, 7)
self._check_content(s, binop.left, 'arg_one')
self._check_content(s, binop.right, 'arg_two')
def test_import_from_multi_line(self):
s = dedent('''
from x.y.z import (
a, b, c as c
)
''').strip()
imp = ast.parse(s).body[0]
self._check_end_pos(imp, 3, 1)
self._check_end_pos(imp.names[2], 2, 16)
def test_slices(self):
s1 = 'f()[1, 2] [0]'
s2 = 'x[ a.b: c.d]'
sm = dedent('''
x[ a.b: f () ,
g () : c.d
]
''').strip()
i1, i2, im = map(self._parse_value, (s1, s2, sm))
self._check_content(s1, i1.value, 'f()[1, 2]')
self._check_content(s1, i1.value.slice, '1, 2')
self._check_content(s2, i2.slice.lower, 'a.b')
self._check_content(s2, i2.slice.upper, 'c.d')
self._check_content(sm, im.slice.elts[0].upper, 'f ()')
self._check_content(sm, im.slice.elts[1].lower, 'g ()')
self._check_end_pos(im, 3, 3)
def test_binop(self):
s = dedent('''
(1 * 2 + (3 ) +
4
)
''').strip()
binop = self._parse_value(s)
self._check_end_pos(binop, 2, 6)
self._check_content(s, binop.right, '4')
self._check_content(s, binop.left, '1 * 2 + (3 )')
self._check_content(s, binop.left.right, '3')
def test_boolop(self):
s = dedent('''
if (one_condition and
(other_condition or yet_another_one)):
pass
''').strip()
bop = ast.parse(s).body[0].test
self._check_end_pos(bop, 2, 44)
self._check_content(s, bop.values[1],
'other_condition or yet_another_one')
def test_tuples(self):
s1 = 'x = () ;'
s2 = 'x = 1 , ;'
s3 = 'x = (1 , 2 ) ;'
sm = dedent('''
x = (
a, b,
)
''').strip()
t1, t2, t3, tm = map(self._parse_value, (s1, s2, s3, sm))
self._check_content(s1, t1, '()')
self._check_content(s2, t2, '1 ,')
self._check_content(s3, t3, '(1 , 2 )')
self._check_end_pos(tm, 3, 1)
def test_attribute_spaces(self):
s = 'func(x. y .z)'
call = self._parse_value(s)
self._check_content(s, call, s)
self._check_content(s, call.args[0], 'x. y .z')
def test_redundant_parenthesis(self):
s = '( ( ( a + b ) ) )'
v = ast.parse(s).body[0].value
self.assertEqual(type(v).__name__, 'BinOp')
self._check_content(s, v, 'a + b')
s2 = 'await ' + s
v = ast.parse(s2).body[0].value.value
self.assertEqual(type(v).__name__, 'BinOp')
self._check_content(s2, v, 'a + b')
def test_trailers_with_redundant_parenthesis(self):
tests = (
('( ( ( a ) ) ) ( )', 'Call'),
('( ( ( a ) ) ) ( b )', 'Call'),
('( ( ( a ) ) ) [ b ]', 'Subscript'),
('( ( ( a ) ) ) . b', 'Attribute'),
)
for s, t in tests:
with self.subTest(s):
v = ast.parse(s).body[0].value
self.assertEqual(type(v).__name__, t)
self._check_content(s, v, s)
s2 = 'await ' + s
v = ast.parse(s2).body[0].value.value
self.assertEqual(type(v).__name__, t)
self._check_content(s2, v, s)
def test_displays(self):
s1 = '[{}, {1, }, {1, 2,} ]'
s2 = '{a: b, f (): g () ,}'
c1 = self._parse_value(s1)
c2 = self._parse_value(s2)
self._check_content(s1, c1.elts[0], '{}')
self._check_content(s1, c1.elts[1], '{1, }')
self._check_content(s1, c1.elts[2], '{1, 2,}')
self._check_content(s2, c2.keys[1], 'f ()')
self._check_content(s2, c2.values[1], 'g ()')
def test_comprehensions(self):
s = dedent('''
x = [{x for x, y in stuff
if cond.x} for stuff in things]
''').strip()
cmp = self._parse_value(s)
self._check_end_pos(cmp, 2, 37)
self._check_content(s, cmp.generators[0].iter, 'things')
self._check_content(s, cmp.elt.generators[0].iter, 'stuff')
self._check_content(s, cmp.elt.generators[0].ifs[0], 'cond.x')
self._check_content(s, cmp.elt.generators[0].target, 'x, y')
def test_yield_await(self):
s = dedent('''
async def f():
yield x
await y
''').strip()
fdef = ast.parse(s).body[0]
self._check_content(s, fdef.body[0].value, 'yield x')
self._check_content(s, fdef.body[1].value, 'await y')
def test_source_segment_multi(self):
s_orig = dedent('''
x = (
a, b,
) + ()
''').strip()
s_tuple = dedent('''
(
a, b,
)
''').strip()
binop = self._parse_value(s_orig)
self.assertEqual(ast.get_source_segment(s_orig, binop.left), s_tuple)
def test_source_segment_padded(self):
s_orig = dedent('''
class C:
def fun(self) -> None:
"ЖЖЖЖЖ"
''').strip()
s_method = ' def fun(self) -> None:\n' \
' "ЖЖЖЖЖ"'
cdef = ast.parse(s_orig).body[0]
self.assertEqual(ast.get_source_segment(s_orig, cdef.body[0], padded=True),
s_method)
def test_source_segment_endings(self):
s = 'v = 1\r\nw = 1\nx = 1\n\ry = 1\rz = 1\r\n'
v, w, x, y, z = ast.parse(s).body
self._check_content(s, v, 'v = 1')
self._check_content(s, w, 'w = 1')
self._check_content(s, x, 'x = 1')
self._check_content(s, y, 'y = 1')
self._check_content(s, z, 'z = 1')
def test_source_segment_tabs(self):
s = dedent('''
class C:
\t\f def fun(self) -> None:
\t\f pass
''').strip()
s_method = ' \t\f def fun(self) -> None:\n' \
' \t\f pass'
cdef = ast.parse(s).body[0]
self.assertEqual(ast.get_source_segment(s, cdef.body[0], padded=True), s_method)
def test_source_segment_newlines(self):
s = 'def f():\n pass\ndef g():\r pass\r\ndef h():\r\n pass\r\n'
f, g, h = ast.parse(s).body
self._check_content(s, f, 'def f():\n pass')
self._check_content(s, g, 'def g():\r pass')
self._check_content(s, h, 'def h():\r\n pass')
s = 'def f():\n a = 1\r b = 2\r\n c = 3\n'
f = ast.parse(s).body[0]
self._check_content(s, f, s.rstrip())
def test_source_segment_missing_info(self):
s = 'v = 1\r\nw = 1\nx = 1\n\ry = 1\r\n'
v, w, x, y = ast.parse(s).body
del v.lineno
del w.end_lineno
del x.col_offset
del y.end_col_offset
self.assertIsNone(ast.get_source_segment(s, v))
self.assertIsNone(ast.get_source_segment(s, w))
self.assertIsNone(ast.get_source_segment(s, x))
self.assertIsNone(ast.get_source_segment(s, y))
class NodeTransformerTests(ASTTestMixin, unittest.TestCase):
def assertASTTransformation(self, transformer_class,
initial_code, expected_code):
initial_ast = ast.parse(dedent(initial_code))
expected_ast = ast.parse(dedent(expected_code))
transformer = transformer_class()
result_ast = ast.fix_missing_locations(transformer.visit(initial_ast))
self.assertASTEqual(result_ast, expected_ast)
def test_node_remove_single(self):
code = 'def func(arg) -> SomeType: ...'
expected = 'def func(arg): ...'
# Since `FunctionDef.returns` is defined as a single value, we test
# the `if isinstance(old_value, AST):` branch here.
class SomeTypeRemover(ast.NodeTransformer):
def visit_Name(self, node: ast.Name):
self.generic_visit(node)
if node.id == 'SomeType':
return None
return node
self.assertASTTransformation(SomeTypeRemover, code, expected)
def test_node_remove_from_list(self):
code = """
def func(arg):
print(arg)
yield arg
"""
expected = """
def func(arg):
print(arg)
"""
# Since `FunctionDef.body` is defined as a list, we test
# the `if isinstance(old_value, list):` branch here.
class YieldRemover(ast.NodeTransformer):
def visit_Expr(self, node: ast.Expr):
self.generic_visit(node)
if isinstance(node.value, ast.Yield):
return None # Remove `yield` from a function
return node
self.assertASTTransformation(YieldRemover, code, expected)
def test_node_return_list(self):
code = """
class DSL(Base, kw1=True): ...
"""
expected = """
class DSL(Base, kw1=True, kw2=True, kw3=False): ...
"""
class ExtendKeywords(ast.NodeTransformer):
def visit_keyword(self, node: ast.keyword):
self.generic_visit(node)
if node.arg == 'kw1':
return [
node,
ast.keyword('kw2', ast.Constant(True)),
ast.keyword('kw3', ast.Constant(False)),
]
return node
self.assertASTTransformation(ExtendKeywords, code, expected)
def test_node_mutate(self):
code = """
def func(arg):
print(arg)
"""
expected = """
def func(arg):
log(arg)
"""
class PrintToLog(ast.NodeTransformer):
def visit_Call(self, node: ast.Call):
self.generic_visit(node)
if isinstance(node.func, ast.Name) and node.func.id == 'print':
node.func.id = 'log'
return node
self.assertASTTransformation(PrintToLog, code, expected)
def test_node_replace(self):
code = """
def func(arg):
print(arg)
"""
expected = """
def func(arg):
logger.log(arg, debug=True)
"""
class PrintToLog(ast.NodeTransformer):
def visit_Call(self, node: ast.Call):
self.generic_visit(node)
if isinstance(node.func, ast.Name) and node.func.id == 'print':
return ast.Call(
func=ast.Attribute(
ast.Name('logger', ctx=ast.Load()),
attr='log',
ctx=ast.Load(),
),
args=node.args,
keywords=[ast.keyword('debug', ast.Constant(True))],
)
return node
self.assertASTTransformation(PrintToLog, code, expected)
class ASTConstructorTests(unittest.TestCase):
"""Test the autogenerated constructors for AST nodes."""
def test_FunctionDef(self):
args = ast.arguments()
self.assertEqual(args.args, [])
self.assertEqual(args.posonlyargs, [])
with self.assertWarnsRegex(DeprecationWarning,
r"FunctionDef\.__init__ missing 1 required positional argument: 'name'"):
node = ast.FunctionDef(args=args)
self.assertFalse(hasattr(node, "name"))
self.assertEqual(node.decorator_list, [])
node = ast.FunctionDef(name='foo', args=args)
self.assertEqual(node.name, 'foo')
self.assertEqual(node.decorator_list, [])
def test_expr_context(self):
name = ast.Name("x")
self.assertEqual(name.id, "x")
self.assertIsInstance(name.ctx, ast.Load)
name2 = ast.Name("x", ast.Store())
self.assertEqual(name2.id, "x")
self.assertIsInstance(name2.ctx, ast.Store)
name3 = ast.Name("x", ctx=ast.Del())
self.assertEqual(name3.id, "x")
self.assertIsInstance(name3.ctx, ast.Del)
with self.assertWarnsRegex(DeprecationWarning,
r"Name\.__init__ missing 1 required positional argument: 'id'"):
name3 = ast.Name()
def test_custom_subclass_with_no_fields(self):
class NoInit(ast.AST):
pass
obj = NoInit()
self.assertIsInstance(obj, NoInit)
self.assertEqual(obj.__dict__, {})
def test_fields_but_no_field_types(self):
class Fields(ast.AST):
_fields = ('a',)
obj = Fields()
with self.assertRaises(AttributeError):
obj.a
obj = Fields(a=1)
self.assertEqual(obj.a, 1)
def test_fields_and_types(self):
class FieldsAndTypes(ast.AST):
_fields = ('a',)
_field_types = {'a': int | None}
a: int | None = None
obj = FieldsAndTypes()
self.assertIs(obj.a, None)
obj = FieldsAndTypes(a=1)
self.assertEqual(obj.a, 1)
def test_custom_attributes(self):
class MyAttrs(ast.AST):
_attributes = ("a", "b")
obj = MyAttrs(a=1, b=2)
self.assertEqual(obj.a, 1)
self.assertEqual(obj.b, 2)
with self.assertWarnsRegex(DeprecationWarning,
r"MyAttrs.__init__ got an unexpected keyword argument 'c'."):
obj = MyAttrs(c=3)
def test_fields_and_types_no_default(self):
class FieldsAndTypesNoDefault(ast.AST):
_fields = ('a',)
_field_types = {'a': int}
with self.assertWarnsRegex(DeprecationWarning,
r"FieldsAndTypesNoDefault\.__init__ missing 1 required positional argument: 'a'\."):
obj = FieldsAndTypesNoDefault()
with self.assertRaises(AttributeError):
obj.a
obj = FieldsAndTypesNoDefault(a=1)
self.assertEqual(obj.a, 1)
def test_incomplete_field_types(self):
class MoreFieldsThanTypes(ast.AST):
_fields = ('a', 'b')
_field_types = {'a': int | None}
a: int | None = None
b: int | None = None
with self.assertWarnsRegex(
DeprecationWarning,
r"Field 'b' is missing from MoreFieldsThanTypes\._field_types"
):
obj = MoreFieldsThanTypes()
self.assertIs(obj.a, None)
self.assertIs(obj.b, None)
obj = MoreFieldsThanTypes(a=1, b=2)
self.assertEqual(obj.a, 1)
self.assertEqual(obj.b, 2)
def test_complete_field_types(self):
class _AllFieldTypes(ast.AST):
_fields = ('a', 'b')
_field_types = {'a': int | None, 'b': list[str]}
# This must be set explicitly
a: int | None = None
# This will add an implicit empty list default
b: list[str]
obj = _AllFieldTypes()
self.assertIs(obj.a, None)
self.assertEqual(obj.b, [])
@support.cpython_only
class ModuleStateTests(unittest.TestCase):
# bpo-41194, bpo-41261, bpo-41631: The _ast module uses a global state.
def check_ast_module(self):
# Check that the _ast module still works as expected
code = 'x + 1'
filename = '<string>'
mode = 'eval'
# Create _ast.AST subclasses instances
ast_tree = compile(code, filename, mode, flags=ast.PyCF_ONLY_AST)
# Call PyAST_Check()
code = compile(ast_tree, filename, mode)
self.assertIsInstance(code, types.CodeType)
def test_reload_module(self):
# bpo-41194: Importing the _ast module twice must not crash.
with support.swap_item(sys.modules, '_ast', None):
del sys.modules['_ast']
import _ast as ast1
del sys.modules['_ast']
import _ast as ast2
self.check_ast_module()
# Unloading the two _ast module instances must not crash.
del ast1
del ast2
support.gc_collect()
self.check_ast_module()
def test_sys_modules(self):
# bpo-41631: Test reproducing a Mercurial crash when PyAST_Check()
# imported the _ast module internally.
lazy_mod = object()
def my_import(name, *args, **kw):
sys.modules[name] = lazy_mod
return lazy_mod
with support.swap_item(sys.modules, '_ast', None):
del sys.modules['_ast']
with support.swap_attr(builtins, '__import__', my_import):
# Test that compile() does not import the _ast module
self.check_ast_module()
self.assertNotIn('_ast', sys.modules)
# Sanity check of the test itself
import _ast
self.assertIs(_ast, lazy_mod)
def test_subinterpreter(self):
# bpo-41631: Importing and using the _ast module in a subinterpreter
# must not crash.
code = dedent('''
import _ast
import ast
import gc
import sys
import types
# Create _ast.AST subclasses instances and call PyAST_Check()
ast_tree = compile('x+1', '<string>', 'eval',
flags=ast.PyCF_ONLY_AST)
code = compile(ast_tree, 'string', 'eval')
if not isinstance(code, types.CodeType):
raise AssertionError
# Unloading the _ast module must not crash.
del ast, _ast
del sys.modules['ast'], sys.modules['_ast']
gc.collect()
''')
res = support.run_in_subinterp(code)
self.assertEqual(res, 0)
class ASTMainTests(unittest.TestCase):
# Tests `ast.main()` function.
def test_cli_file_input(self):
code = "print(1, 2, 3)"
expected = ast.dump(ast.parse(code), indent=3)
with os_helper.temp_dir() as tmp_dir:
filename = os.path.join(tmp_dir, "test_module.py")
with open(filename, 'w', encoding='utf-8') as f:
f.write(code)
res, _ = script_helper.run_python_until_end("-m", "ast", filename)
self.assertEqual(res.err, b"")
self.assertEqual(expected.splitlines(),
res.out.decode("utf8").splitlines())
self.assertEqual(res.rc, 0)
class ASTOptimiziationTests(unittest.TestCase):
binop = {
"+": ast.Add(),
"-": ast.Sub(),
"*": ast.Mult(),
"/": ast.Div(),
"%": ast.Mod(),
"<<": ast.LShift(),
">>": ast.RShift(),
"|": ast.BitOr(),
"^": ast.BitXor(),
"&": ast.BitAnd(),
"//": ast.FloorDiv(),
"**": ast.Pow(),
}
unaryop = {
"~": ast.Invert(),
"+": ast.UAdd(),
"-": ast.USub(),
}
def wrap_expr(self, expr):
return ast.Module(body=[ast.Expr(value=expr)])
def wrap_statement(self, statement):
return ast.Module(body=[statement])
def assert_ast(self, code, non_optimized_target, optimized_target):
non_optimized_tree = ast.parse(code, optimize=-1)
optimized_tree = ast.parse(code, optimize=1)
# Is a non-optimized tree equal to a non-optimized target?
self.assertTrue(
ast.compare(non_optimized_tree, non_optimized_target),
f"{ast.dump(non_optimized_target)} must equal "
f"{ast.dump(non_optimized_tree)}",
)
# Is a optimized tree equal to a non-optimized target?
self.assertFalse(
ast.compare(optimized_tree, non_optimized_target),
f"{ast.dump(non_optimized_target)} must not equal "
f"{ast.dump(non_optimized_tree)}"
)
# Is a optimized tree is equal to an optimized target?
self.assertTrue(
ast.compare(optimized_tree, optimized_target),
f"{ast.dump(optimized_target)} must equal "
f"{ast.dump(optimized_tree)}",
)
def create_binop(self, operand, left=ast.Constant(1), right=ast.Constant(1)):
return ast.BinOp(left=left, op=self.binop[operand], right=right)
def test_folding_binop(self):
code = "1 %s 1"
operators = self.binop.keys()
for op in operators:
result_code = code % op
non_optimized_target = self.wrap_expr(self.create_binop(op))
optimized_target = self.wrap_expr(ast.Constant(value=eval(result_code)))
with self.subTest(
result_code=result_code,
non_optimized_target=non_optimized_target,
optimized_target=optimized_target
):
self.assert_ast(result_code, non_optimized_target, optimized_target)
# Multiplication of constant tuples must be folded
code = "(1,) * 3"
non_optimized_target = self.wrap_expr(self.create_binop("*", ast.Tuple(elts=[ast.Constant(value=1)]), ast.Constant(value=3)))
optimized_target = self.wrap_expr(ast.Constant(eval(code)))
self.assert_ast(code, non_optimized_target, optimized_target)
def test_folding_unaryop(self):
code = "%s1"
operators = self.unaryop.keys()
def create_unaryop(operand):
return ast.UnaryOp(op=self.unaryop[operand], operand=ast.Constant(1))
for op in operators:
result_code = code % op
non_optimized_target = self.wrap_expr(create_unaryop(op))
optimized_target = self.wrap_expr(ast.Constant(eval(result_code)))
with self.subTest(
result_code=result_code,
non_optimized_target=non_optimized_target,
optimized_target=optimized_target
):
self.assert_ast(result_code, non_optimized_target, optimized_target)
def test_folding_not(self):
code = "not (1 %s (1,))"
operators = {
"in": ast.In(),
"is": ast.Is(),
}
opt_operators = {
"is": ast.IsNot(),
"in": ast.NotIn(),
}
def create_notop(operand):
return ast.UnaryOp(op=ast.Not(), operand=ast.Compare(
left=ast.Constant(value=1),
ops=[operators[operand]],
comparators=[ast.Tuple(elts=[ast.Constant(value=1)])]
))
for op in operators.keys():
result_code = code % op
non_optimized_target = self.wrap_expr(create_notop(op))
optimized_target = self.wrap_expr(
ast.Compare(left=ast.Constant(1), ops=[opt_operators[op]], comparators=[ast.Constant(value=(1,))])
)
with self.subTest(
result_code=result_code,
non_optimized_target=non_optimized_target,
optimized_target=optimized_target
):
self.assert_ast(result_code, non_optimized_target, optimized_target)
def test_folding_format(self):
code = "'%s' % (a,)"
non_optimized_target = self.wrap_expr(
ast.BinOp(
left=ast.Constant(value="%s"),
op=ast.Mod(),
right=ast.Tuple(elts=[ast.Name(id='a')]))
)
optimized_target = self.wrap_expr(
ast.JoinedStr(
values=[
ast.FormattedValue(value=ast.Name(id='a'), conversion=115)
]
)
)
self.assert_ast(code, non_optimized_target, optimized_target)
def test_folding_tuple(self):
code = "(1,)"
non_optimized_target = self.wrap_expr(ast.Tuple(elts=[ast.Constant(1)]))
optimized_target = self.wrap_expr(ast.Constant(value=(1,)))
self.assert_ast(code, non_optimized_target, optimized_target)
def test_folding_comparator(self):
code = "1 %s %s1%s"
operators = [("in", ast.In()), ("not in", ast.NotIn())]
braces = [
("[", "]", ast.List, (1,)),
("{", "}", ast.Set, frozenset({1})),
]
for left, right, non_optimized_comparator, optimized_comparator in braces:
for op, node in operators:
non_optimized_target = self.wrap_expr(ast.Compare(
left=ast.Constant(1), ops=[node],
comparators=[non_optimized_comparator(elts=[ast.Constant(1)])]
))
optimized_target = self.wrap_expr(ast.Compare(
left=ast.Constant(1), ops=[node],
comparators=[ast.Constant(value=optimized_comparator)]
))
self.assert_ast(code % (op, left, right), non_optimized_target, optimized_target)
def test_folding_iter(self):
code = "for _ in %s1%s: pass"
braces = [
("[", "]", ast.List, (1,)),
("{", "}", ast.Set, frozenset({1})),
]
for left, right, ast_cls, optimized_iter in braces:
non_optimized_target = self.wrap_statement(ast.For(
target=ast.Name(id="_", ctx=ast.Store()),
iter=ast_cls(elts=[ast.Constant(1)]),
body=[ast.Pass()]
))
optimized_target = self.wrap_statement(ast.For(
target=ast.Name(id="_", ctx=ast.Store()),
iter=ast.Constant(value=optimized_iter),
body=[ast.Pass()]
))
self.assert_ast(code % (left, right), non_optimized_target, optimized_target)
def test_folding_subscript(self):
code = "(1,)[0]"
non_optimized_target = self.wrap_expr(
ast.Subscript(value=ast.Tuple(elts=[ast.Constant(value=1)]), slice=ast.Constant(value=0))
)
optimized_target = self.wrap_expr(ast.Constant(value=1))
self.assert_ast(code, non_optimized_target, optimized_target)
def test_folding_type_param_in_function_def(self):
code = "def foo[%s = 1 + 1](): pass"
unoptimized_binop = self.create_binop("+")
unoptimized_type_params = [
("T", "T", ast.TypeVar),
("**P", "P", ast.ParamSpec),
("*Ts", "Ts", ast.TypeVarTuple),
]
for type, name, type_param in unoptimized_type_params:
result_code = code % type
optimized_target = self.wrap_statement(
ast.FunctionDef(
name='foo',
args=ast.arguments(),
body=[ast.Pass()],
type_params=[type_param(name=name, default_value=ast.Constant(2))]
)
)
non_optimized_target = self.wrap_statement(
ast.FunctionDef(
name='foo',
args=ast.arguments(),
body=[ast.Pass()],
type_params=[type_param(name=name, default_value=unoptimized_binop)]
)
)
self.assert_ast(result_code, non_optimized_target, optimized_target)
def test_folding_type_param_in_class_def(self):
code = "class foo[%s = 1 + 1]: pass"
unoptimized_binop = self.create_binop("+")
unoptimized_type_params = [
("T", "T", ast.TypeVar),
("**P", "P", ast.ParamSpec),
("*Ts", "Ts", ast.TypeVarTuple),
]
for type, name, type_param in unoptimized_type_params:
result_code = code % type
optimized_target = self.wrap_statement(
ast.ClassDef(
name='foo',
body=[ast.Pass()],
type_params=[type_param(name=name, default_value=ast.Constant(2))]
)
)
non_optimized_target = self.wrap_statement(
ast.ClassDef(
name='foo',
body=[ast.Pass()],
type_params=[type_param(name=name, default_value=unoptimized_binop)]
)
)
self.assert_ast(result_code, non_optimized_target, optimized_target)
def test_folding_type_param_in_type_alias(self):
code = "type foo[%s = 1 + 1] = 1"
unoptimized_binop = self.create_binop("+")
unoptimized_type_params = [
("T", "T", ast.TypeVar),
("**P", "P", ast.ParamSpec),
("*Ts", "Ts", ast.TypeVarTuple),
]
for type, name, type_param in unoptimized_type_params:
result_code = code % type
optimized_target = self.wrap_statement(
ast.TypeAlias(
name=ast.Name(id='foo', ctx=ast.Store()),
type_params=[type_param(name=name, default_value=ast.Constant(2))],
value=ast.Constant(value=1),
)
)
non_optimized_target = self.wrap_statement(
ast.TypeAlias(
name=ast.Name(id='foo', ctx=ast.Store()),
type_params=[type_param(name=name, default_value=unoptimized_binop)],
value=ast.Constant(value=1),
)
)
self.assert_ast(result_code, non_optimized_target, optimized_target)
if __name__ == "__main__":
unittest.main()