cpython/Lib/test/test_tools/test_unparse.py

292 lines
7.4 KiB
Python

"""Tests for the unparse.py script in the Tools/parser directory."""
import unittest
import test.support
import io
import os
import random
import tokenize
import ast
from test.test_tools import basepath, toolsdir, skip_if_missing
skip_if_missing()
parser_path = os.path.join(toolsdir, "parser")
with test.support.DirsOnSysPath(parser_path):
import unparse
def read_pyfile(filename):
"""Read and return the contents of a Python source file (as a
string), taking into account the file encoding."""
with open(filename, "rb") as pyfile:
encoding = tokenize.detect_encoding(pyfile.readline)[0]
with open(filename, "r", encoding=encoding) as pyfile:
source = pyfile.read()
return source
for_else = """\
def f():
for x in range(10):
break
else:
y = 2
z = 3
"""
while_else = """\
def g():
while True:
break
else:
y = 2
z = 3
"""
relative_import = """\
from . import fred
from .. import barney
from .australia import shrimp as prawns
"""
nonlocal_ex = """\
def f():
x = 1
def g():
nonlocal x
x = 2
y = 7
def h():
nonlocal x, y
"""
# also acts as test for 'except ... as ...'
raise_from = """\
try:
1 / 0
except ZeroDivisionError as e:
raise ArithmeticError from e
"""
class_decorator = """\
@f1(arg)
@f2
class Foo: pass
"""
elif1 = """\
if cond1:
suite1
elif cond2:
suite2
else:
suite3
"""
elif2 = """\
if cond1:
suite1
elif cond2:
suite2
"""
try_except_finally = """\
try:
suite1
except ex1:
suite2
except ex2:
suite3
else:
suite4
finally:
suite5
"""
with_simple = """\
with f():
suite1
"""
with_as = """\
with f() as x:
suite1
"""
with_two_items = """\
with f() as x, g() as y:
suite1
"""
class ASTTestCase(unittest.TestCase):
def assertASTEqual(self, ast1, ast2):
self.assertEqual(ast.dump(ast1), ast.dump(ast2))
def check_roundtrip(self, code1, filename="internal"):
ast1 = compile(code1, filename, "exec", ast.PyCF_ONLY_AST)
unparse_buffer = io.StringIO()
unparse.Unparser(ast1, unparse_buffer)
code2 = unparse_buffer.getvalue()
ast2 = compile(code2, filename, "exec", ast.PyCF_ONLY_AST)
self.assertASTEqual(ast1, ast2)
class UnparseTestCase(ASTTestCase):
# Tests for specific bugs found in earlier versions of unparse
def test_fstrings(self):
# See issue 25180
self.check_roundtrip(r"""f'{f"{0}"*3}'""")
self.check_roundtrip(r"""f'{f"{y}"*3}'""")
self.check_roundtrip(r"""f'{f"{\'x\'}"*3}'""")
self.check_roundtrip(r'''f"{r'x' f'{\"s\"}'}"''')
self.check_roundtrip(r'''f"{r'x'rf'{\"s\"}'}"''')
def test_del_statement(self):
self.check_roundtrip("del x, y, z")
def test_shifts(self):
self.check_roundtrip("45 << 2")
self.check_roundtrip("13 >> 7")
def test_for_else(self):
self.check_roundtrip(for_else)
def test_while_else(self):
self.check_roundtrip(while_else)
def test_unary_parens(self):
self.check_roundtrip("(-1)**7")
self.check_roundtrip("(-1.)**8")
self.check_roundtrip("(-1j)**6")
self.check_roundtrip("not True or False")
self.check_roundtrip("True or not False")
def test_integer_parens(self):
self.check_roundtrip("3 .__abs__()")
def test_huge_float(self):
self.check_roundtrip("1e1000")
self.check_roundtrip("-1e1000")
self.check_roundtrip("1e1000j")
self.check_roundtrip("-1e1000j")
def test_min_int(self):
self.check_roundtrip(str(-2**31))
self.check_roundtrip(str(-2**63))
def test_imaginary_literals(self):
self.check_roundtrip("7j")
self.check_roundtrip("-7j")
self.check_roundtrip("0j")
self.check_roundtrip("-0j")
def test_lambda_parentheses(self):
self.check_roundtrip("(lambda: int)()")
def test_chained_comparisons(self):
self.check_roundtrip("1 < 4 <= 5")
self.check_roundtrip("a is b is c is not d")
def test_function_arguments(self):
self.check_roundtrip("def f(): pass")
self.check_roundtrip("def f(a): pass")
self.check_roundtrip("def f(b = 2): pass")
self.check_roundtrip("def f(a, b): pass")
self.check_roundtrip("def f(a, b = 2): pass")
self.check_roundtrip("def f(a = 5, b = 2): pass")
self.check_roundtrip("def f(*, a = 1, b = 2): pass")
self.check_roundtrip("def f(*, a = 1, b): pass")
self.check_roundtrip("def f(*, a, b = 2): pass")
self.check_roundtrip("def f(a, b = None, *, c, **kwds): pass")
self.check_roundtrip("def f(a=2, *args, c=5, d, **kwds): pass")
self.check_roundtrip("def f(*args, **kwargs): pass")
def test_relative_import(self):
self.check_roundtrip(relative_import)
def test_nonlocal(self):
self.check_roundtrip(nonlocal_ex)
def test_raise_from(self):
self.check_roundtrip(raise_from)
def test_bytes(self):
self.check_roundtrip("b'123'")
def test_annotations(self):
self.check_roundtrip("def f(a : int): pass")
self.check_roundtrip("def f(a: int = 5): pass")
self.check_roundtrip("def f(*args: [int]): pass")
self.check_roundtrip("def f(**kwargs: dict): pass")
self.check_roundtrip("def f() -> None: pass")
def test_set_literal(self):
self.check_roundtrip("{'a', 'b', 'c'}")
def test_set_comprehension(self):
self.check_roundtrip("{x for x in range(5)}")
def test_dict_comprehension(self):
self.check_roundtrip("{x: x*x for x in range(10)}")
def test_class_decorators(self):
self.check_roundtrip(class_decorator)
def test_class_definition(self):
self.check_roundtrip("class A(metaclass=type, *[], **{}): pass")
def test_elifs(self):
self.check_roundtrip(elif1)
self.check_roundtrip(elif2)
def test_try_except_finally(self):
self.check_roundtrip(try_except_finally)
def test_starred_assignment(self):
self.check_roundtrip("a, *b, c = seq")
self.check_roundtrip("a, (*b, c) = seq")
self.check_roundtrip("a, *b[0], c = seq")
self.check_roundtrip("a, *(b, c) = seq")
def test_with_simple(self):
self.check_roundtrip(with_simple)
def test_with_as(self):
self.check_roundtrip(with_as)
def test_with_two_items(self):
self.check_roundtrip(with_two_items)
class DirectoryTestCase(ASTTestCase):
"""Test roundtrip behaviour on all files in Lib and Lib/test."""
# test directories, relative to the root of the distribution
test_directories = 'Lib', os.path.join('Lib', 'test')
def test_files(self):
# get names of files to test
names = []
for d in self.test_directories:
test_dir = os.path.join(basepath, d)
for n in os.listdir(test_dir):
if n.endswith('.py') and not n.startswith('bad'):
names.append(os.path.join(test_dir, n))
# Test limited subset of files unless the 'cpu' resource is specified.
if not test.support.is_resource_enabled("cpu"):
names = random.sample(names, 10)
for filename in names:
if test.support.verbose:
print('Testing %s' % filename)
source = read_pyfile(filename)
self.check_roundtrip(source)
if __name__ == '__main__':
unittest.main()