cpython/Lib/test/test_compile.py

1535 lines
51 KiB
Python

import dis
import math
import os
import unittest
import sys
import ast
import _ast
import tempfile
import types
import textwrap
from test import support
from test.support import script_helper, requires_debug_ranges
from test.support.os_helper import FakePath
class TestSpecifics(unittest.TestCase):
def compile_single(self, source):
compile(source, "<single>", "single")
def assertInvalidSingle(self, source):
self.assertRaises(SyntaxError, self.compile_single, source)
def test_no_ending_newline(self):
compile("hi", "<test>", "exec")
compile("hi\r", "<test>", "exec")
def test_empty(self):
compile("", "<test>", "exec")
def test_other_newlines(self):
compile("\r\n", "<test>", "exec")
compile("\r", "<test>", "exec")
compile("hi\r\nstuff\r\ndef f():\n pass\r", "<test>", "exec")
compile("this_is\rreally_old_mac\rdef f():\n pass", "<test>", "exec")
def test_debug_assignment(self):
# catch assignments to __debug__
self.assertRaises(SyntaxError, compile, '__debug__ = 1', '?', 'single')
import builtins
prev = builtins.__debug__
setattr(builtins, '__debug__', 'sure')
self.assertEqual(__debug__, prev)
setattr(builtins, '__debug__', prev)
def test_argument_handling(self):
# detect duplicate positional and keyword arguments
self.assertRaises(SyntaxError, eval, 'lambda a,a:0')
self.assertRaises(SyntaxError, eval, 'lambda a,a=1:0')
self.assertRaises(SyntaxError, eval, 'lambda a=1,a=1:0')
self.assertRaises(SyntaxError, exec, 'def f(a, a): pass')
self.assertRaises(SyntaxError, exec, 'def f(a = 0, a = 1): pass')
self.assertRaises(SyntaxError, exec, 'def f(a): global a; a = 1')
def test_syntax_error(self):
self.assertRaises(SyntaxError, compile, "1+*3", "filename", "exec")
def test_none_keyword_arg(self):
self.assertRaises(SyntaxError, compile, "f(None=1)", "<string>", "exec")
def test_duplicate_global_local(self):
self.assertRaises(SyntaxError, exec, 'def f(a): global a; a = 1')
def test_exec_with_general_mapping_for_locals(self):
class M:
"Test mapping interface versus possible calls from eval()."
def __getitem__(self, key):
if key == 'a':
return 12
raise KeyError
def __setitem__(self, key, value):
self.results = (key, value)
def keys(self):
return list('xyz')
m = M()
g = globals()
exec('z = a', g, m)
self.assertEqual(m.results, ('z', 12))
try:
exec('z = b', g, m)
except NameError:
pass
else:
self.fail('Did not detect a KeyError')
exec('z = dir()', g, m)
self.assertEqual(m.results, ('z', list('xyz')))
exec('z = globals()', g, m)
self.assertEqual(m.results, ('z', g))
exec('z = locals()', g, m)
self.assertEqual(m.results, ('z', m))
self.assertRaises(TypeError, exec, 'z = b', m)
class A:
"Non-mapping"
pass
m = A()
self.assertRaises(TypeError, exec, 'z = a', g, m)
# Verify that dict subclasses work as well
class D(dict):
def __getitem__(self, key):
if key == 'a':
return 12
return dict.__getitem__(self, key)
d = D()
exec('z = a', g, d)
self.assertEqual(d['z'], 12)
def test_extended_arg(self):
longexpr = 'x = x or ' + '-x' * 2500
g = {}
code = '''
def f(x):
%s
%s
%s
%s
%s
%s
%s
%s
%s
%s
# the expressions above have no effect, x == argument
while x:
x -= 1
# EXTENDED_ARG/JUMP_ABSOLUTE here
return x
''' % ((longexpr,)*10)
exec(code, g)
self.assertEqual(g['f'](5), 0)
def test_argument_order(self):
self.assertRaises(SyntaxError, exec, 'def f(a=1, b): pass')
def test_float_literals(self):
# testing bad float literals
self.assertRaises(SyntaxError, eval, "2e")
self.assertRaises(SyntaxError, eval, "2.0e+")
self.assertRaises(SyntaxError, eval, "1e-")
self.assertRaises(SyntaxError, eval, "3-4e/21")
def test_indentation(self):
# testing compile() of indented block w/o trailing newline"
s = """
if 1:
if 2:
pass"""
compile(s, "<string>", "exec")
# This test is probably specific to CPython and may not generalize
# to other implementations. We are trying to ensure that when
# the first line of code starts after 256, correct line numbers
# in tracebacks are still produced.
def test_leading_newlines(self):
s256 = "".join(["\n"] * 256 + ["spam"])
co = compile(s256, 'fn', 'exec')
self.assertEqual(co.co_firstlineno, 1)
lines = list(co.co_lines())
self.assertEqual(lines[0][2], None)
self.assertEqual(lines[1][2], 257)
def test_literals_with_leading_zeroes(self):
for arg in ["077787", "0xj", "0x.", "0e", "090000000000000",
"080000000000000", "000000000000009", "000000000000008",
"0b42", "0BADCAFE", "0o123456789", "0b1.1", "0o4.2",
"0b101j", "0o153j", "0b100e1", "0o777e1", "0777",
"000777", "000000000000007"]:
self.assertRaises(SyntaxError, eval, arg)
self.assertEqual(eval("0xff"), 255)
self.assertEqual(eval("0777."), 777)
self.assertEqual(eval("0777.0"), 777)
self.assertEqual(eval("000000000000000000000000000000000000000000000000000777e0"), 777)
self.assertEqual(eval("0777e1"), 7770)
self.assertEqual(eval("0e0"), 0)
self.assertEqual(eval("0000e-012"), 0)
self.assertEqual(eval("09.5"), 9.5)
self.assertEqual(eval("0777j"), 777j)
self.assertEqual(eval("000"), 0)
self.assertEqual(eval("00j"), 0j)
self.assertEqual(eval("00.0"), 0)
self.assertEqual(eval("0e3"), 0)
self.assertEqual(eval("090000000000000."), 90000000000000.)
self.assertEqual(eval("090000000000000.0000000000000000000000"), 90000000000000.)
self.assertEqual(eval("090000000000000e0"), 90000000000000.)
self.assertEqual(eval("090000000000000e-0"), 90000000000000.)
self.assertEqual(eval("090000000000000j"), 90000000000000j)
self.assertEqual(eval("000000000000008."), 8.)
self.assertEqual(eval("000000000000009."), 9.)
self.assertEqual(eval("0b101010"), 42)
self.assertEqual(eval("-0b000000000010"), -2)
self.assertEqual(eval("0o777"), 511)
self.assertEqual(eval("-0o0000010"), -8)
def test_unary_minus(self):
# Verify treatment of unary minus on negative numbers SF bug #660455
if sys.maxsize == 2147483647:
# 32-bit machine
all_one_bits = '0xffffffff'
self.assertEqual(eval(all_one_bits), 4294967295)
self.assertEqual(eval("-" + all_one_bits), -4294967295)
elif sys.maxsize == 9223372036854775807:
# 64-bit machine
all_one_bits = '0xffffffffffffffff'
self.assertEqual(eval(all_one_bits), 18446744073709551615)
self.assertEqual(eval("-" + all_one_bits), -18446744073709551615)
else:
self.fail("How many bits *does* this machine have???")
# Verify treatment of constant folding on -(sys.maxsize+1)
# i.e. -2147483648 on 32 bit platforms. Should return int.
self.assertIsInstance(eval("%s" % (-sys.maxsize - 1)), int)
self.assertIsInstance(eval("%s" % (-sys.maxsize - 2)), int)
if sys.maxsize == 9223372036854775807:
def test_32_63_bit_values(self):
a = +4294967296 # 1 << 32
b = -4294967296 # 1 << 32
c = +281474976710656 # 1 << 48
d = -281474976710656 # 1 << 48
e = +4611686018427387904 # 1 << 62
f = -4611686018427387904 # 1 << 62
g = +9223372036854775807 # 1 << 63 - 1
h = -9223372036854775807 # 1 << 63 - 1
for variable in self.test_32_63_bit_values.__code__.co_consts:
if variable is not None:
self.assertIsInstance(variable, int)
def test_sequence_unpacking_error(self):
# Verify sequence packing/unpacking with "or". SF bug #757818
i,j = (1, -1) or (-1, 1)
self.assertEqual(i, 1)
self.assertEqual(j, -1)
def test_none_assignment(self):
stmts = [
'None = 0',
'None += 0',
'__builtins__.None = 0',
'def None(): pass',
'class None: pass',
'(a, None) = 0, 0',
'for None in range(10): pass',
'def f(None): pass',
'import None',
'import x as None',
'from x import None',
'from x import y as None'
]
for stmt in stmts:
stmt += "\n"
self.assertRaises(SyntaxError, compile, stmt, 'tmp', 'single')
self.assertRaises(SyntaxError, compile, stmt, 'tmp', 'exec')
def test_import(self):
succeed = [
'import sys',
'import os, sys',
'import os as bar',
'import os.path as bar',
'from __future__ import nested_scopes, generators',
'from __future__ import (nested_scopes,\ngenerators)',
'from __future__ import (nested_scopes,\ngenerators,)',
'from sys import stdin, stderr, stdout',
'from sys import (stdin, stderr,\nstdout)',
'from sys import (stdin, stderr,\nstdout,)',
'from sys import (stdin\n, stderr, stdout)',
'from sys import (stdin\n, stderr, stdout,)',
'from sys import stdin as si, stdout as so, stderr as se',
'from sys import (stdin as si, stdout as so, stderr as se)',
'from sys import (stdin as si, stdout as so, stderr as se,)',
]
fail = [
'import (os, sys)',
'import (os), (sys)',
'import ((os), (sys))',
'import (sys',
'import sys)',
'import (os,)',
'import os As bar',
'import os.path a bar',
'from sys import stdin As stdout',
'from sys import stdin a stdout',
'from (sys) import stdin',
'from __future__ import (nested_scopes',
'from __future__ import nested_scopes)',
'from __future__ import nested_scopes,\ngenerators',
'from sys import (stdin',
'from sys import stdin)',
'from sys import stdin, stdout,\nstderr',
'from sys import stdin si',
'from sys import stdin,',
'from sys import (*)',
'from sys import (stdin,, stdout, stderr)',
'from sys import (stdin, stdout),',
]
for stmt in succeed:
compile(stmt, 'tmp', 'exec')
for stmt in fail:
self.assertRaises(SyntaxError, compile, stmt, 'tmp', 'exec')
def test_for_distinct_code_objects(self):
# SF bug 1048870
def f():
f1 = lambda x=1: x
f2 = lambda x=2: x
return f1, f2
f1, f2 = f()
self.assertNotEqual(id(f1.__code__), id(f2.__code__))
def test_lambda_doc(self):
l = lambda: "foo"
self.assertIsNone(l.__doc__)
def test_encoding(self):
code = b'# -*- coding: badencoding -*-\npass\n'
self.assertRaises(SyntaxError, compile, code, 'tmp', 'exec')
code = '# -*- coding: badencoding -*-\n"\xc2\xa4"\n'
compile(code, 'tmp', 'exec')
self.assertEqual(eval(code), '\xc2\xa4')
code = '"\xc2\xa4"\n'
self.assertEqual(eval(code), '\xc2\xa4')
code = b'"\xc2\xa4"\n'
self.assertEqual(eval(code), '\xa4')
code = b'# -*- coding: latin1 -*-\n"\xc2\xa4"\n'
self.assertEqual(eval(code), '\xc2\xa4')
code = b'# -*- coding: utf-8 -*-\n"\xc2\xa4"\n'
self.assertEqual(eval(code), '\xa4')
code = b'# -*- coding: iso8859-15 -*-\n"\xc2\xa4"\n'
self.assertEqual(eval(code), '\xc2\u20ac')
code = '"""\\\n# -*- coding: iso8859-15 -*-\n\xc2\xa4"""\n'
self.assertEqual(eval(code), '# -*- coding: iso8859-15 -*-\n\xc2\xa4')
code = b'"""\\\n# -*- coding: iso8859-15 -*-\n\xc2\xa4"""\n'
self.assertEqual(eval(code), '# -*- coding: iso8859-15 -*-\n\xa4')
def test_subscripts(self):
# SF bug 1448804
# Class to make testing subscript results easy
class str_map(object):
def __init__(self):
self.data = {}
def __getitem__(self, key):
return self.data[str(key)]
def __setitem__(self, key, value):
self.data[str(key)] = value
def __delitem__(self, key):
del self.data[str(key)]
def __contains__(self, key):
return str(key) in self.data
d = str_map()
# Index
d[1] = 1
self.assertEqual(d[1], 1)
d[1] += 1
self.assertEqual(d[1], 2)
del d[1]
self.assertNotIn(1, d)
# Tuple of indices
d[1, 1] = 1
self.assertEqual(d[1, 1], 1)
d[1, 1] += 1
self.assertEqual(d[1, 1], 2)
del d[1, 1]
self.assertNotIn((1, 1), d)
# Simple slice
d[1:2] = 1
self.assertEqual(d[1:2], 1)
d[1:2] += 1
self.assertEqual(d[1:2], 2)
del d[1:2]
self.assertNotIn(slice(1, 2), d)
# Tuple of simple slices
d[1:2, 1:2] = 1
self.assertEqual(d[1:2, 1:2], 1)
d[1:2, 1:2] += 1
self.assertEqual(d[1:2, 1:2], 2)
del d[1:2, 1:2]
self.assertNotIn((slice(1, 2), slice(1, 2)), d)
# Extended slice
d[1:2:3] = 1
self.assertEqual(d[1:2:3], 1)
d[1:2:3] += 1
self.assertEqual(d[1:2:3], 2)
del d[1:2:3]
self.assertNotIn(slice(1, 2, 3), d)
# Tuple of extended slices
d[1:2:3, 1:2:3] = 1
self.assertEqual(d[1:2:3, 1:2:3], 1)
d[1:2:3, 1:2:3] += 1
self.assertEqual(d[1:2:3, 1:2:3], 2)
del d[1:2:3, 1:2:3]
self.assertNotIn((slice(1, 2, 3), slice(1, 2, 3)), d)
# Ellipsis
d[...] = 1
self.assertEqual(d[...], 1)
d[...] += 1
self.assertEqual(d[...], 2)
del d[...]
self.assertNotIn(Ellipsis, d)
# Tuple of Ellipses
d[..., ...] = 1
self.assertEqual(d[..., ...], 1)
d[..., ...] += 1
self.assertEqual(d[..., ...], 2)
del d[..., ...]
self.assertNotIn((Ellipsis, Ellipsis), d)
def test_annotation_limit(self):
# more than 255 annotations, should compile ok
s = "def f(%s): pass"
s %= ', '.join('a%d:%d' % (i,i) for i in range(300))
compile(s, '?', 'exec')
def test_mangling(self):
class A:
def f():
__mangled = 1
__not_mangled__ = 2
import __mangled_mod
import __package__.module
self.assertIn("_A__mangled", A.f.__code__.co_varnames)
self.assertIn("__not_mangled__", A.f.__code__.co_varnames)
self.assertIn("_A__mangled_mod", A.f.__code__.co_varnames)
self.assertIn("__package__", A.f.__code__.co_varnames)
def test_compile_ast(self):
fname = __file__
if fname.lower().endswith('pyc'):
fname = fname[:-1]
with open(fname, encoding='utf-8') as f:
fcontents = f.read()
sample_code = [
['<assign>', 'x = 5'],
['<ifblock>', """if True:\n pass\n"""],
['<forblock>', """for n in [1, 2, 3]:\n print(n)\n"""],
['<deffunc>', """def foo():\n pass\nfoo()\n"""],
[fname, fcontents],
]
for fname, code in sample_code:
co1 = compile(code, '%s1' % fname, 'exec')
ast = compile(code, '%s2' % fname, 'exec', _ast.PyCF_ONLY_AST)
self.assertTrue(type(ast) == _ast.Module)
co2 = compile(ast, '%s3' % fname, 'exec')
self.assertEqual(co1, co2)
# the code object's filename comes from the second compilation step
self.assertEqual(co2.co_filename, '%s3' % fname)
# raise exception when node type doesn't match with compile mode
co1 = compile('print(1)', '<string>', 'exec', _ast.PyCF_ONLY_AST)
self.assertRaises(TypeError, compile, co1, '<ast>', 'eval')
# raise exception when node type is no start node
self.assertRaises(TypeError, compile, _ast.If(), '<ast>', 'exec')
# raise exception when node has invalid children
ast = _ast.Module()
ast.body = [_ast.BoolOp()]
self.assertRaises(TypeError, compile, ast, '<ast>', 'exec')
def test_dict_evaluation_order(self):
i = 0
def f():
nonlocal i
i += 1
return i
d = {f(): f(), f(): f()}
self.assertEqual(d, {1: 2, 3: 4})
def test_compile_filename(self):
for filename in 'file.py', b'file.py':
code = compile('pass', filename, 'exec')
self.assertEqual(code.co_filename, 'file.py')
for filename in bytearray(b'file.py'), memoryview(b'file.py'):
with self.assertWarns(DeprecationWarning):
code = compile('pass', filename, 'exec')
self.assertEqual(code.co_filename, 'file.py')
self.assertRaises(TypeError, compile, 'pass', list(b'file.py'), 'exec')
@support.cpython_only
def test_same_filename_used(self):
s = """def f(): pass\ndef g(): pass"""
c = compile(s, "myfile", "exec")
for obj in c.co_consts:
if isinstance(obj, types.CodeType):
self.assertIs(obj.co_filename, c.co_filename)
def test_single_statement(self):
self.compile_single("1 + 2")
self.compile_single("\n1 + 2")
self.compile_single("1 + 2\n")
self.compile_single("1 + 2\n\n")
self.compile_single("1 + 2\t\t\n")
self.compile_single("1 + 2\t\t\n ")
self.compile_single("1 + 2 # one plus two")
self.compile_single("1; 2")
self.compile_single("import sys; sys")
self.compile_single("def f():\n pass")
self.compile_single("while False:\n pass")
self.compile_single("if x:\n f(x)")
self.compile_single("if x:\n f(x)\nelse:\n g(x)")
self.compile_single("class T:\n pass")
self.compile_single("c = '''\na=1\nb=2\nc=3\n'''")
def test_bad_single_statement(self):
self.assertInvalidSingle('1\n2')
self.assertInvalidSingle('def f(): pass')
self.assertInvalidSingle('a = 13\nb = 187')
self.assertInvalidSingle('del x\ndel y')
self.assertInvalidSingle('f()\ng()')
self.assertInvalidSingle('f()\n# blah\nblah()')
self.assertInvalidSingle('f()\nxy # blah\nblah()')
self.assertInvalidSingle('x = 5 # comment\nx = 6\n')
self.assertInvalidSingle("c = '''\nd=1\n'''\na = 1\n\nb = 2\n")
def test_particularly_evil_undecodable(self):
# Issue 24022
src = b'0000\x00\n00000000000\n\x00\n\x9e\n'
with tempfile.TemporaryDirectory() as tmpd:
fn = os.path.join(tmpd, "bad.py")
with open(fn, "wb") as fp:
fp.write(src)
res = script_helper.run_python_until_end(fn)[0]
self.assertIn(b"Non-UTF-8", res.err)
def test_yet_more_evil_still_undecodable(self):
# Issue #25388
src = b"#\x00\n#\xfd\n"
with tempfile.TemporaryDirectory() as tmpd:
fn = os.path.join(tmpd, "bad.py")
with open(fn, "wb") as fp:
fp.write(src)
res = script_helper.run_python_until_end(fn)[0]
self.assertIn(b"Non-UTF-8", res.err)
@support.cpython_only
def test_compiler_recursion_limit(self):
# Expected limit is sys.getrecursionlimit() * the scaling factor
# in symtable.c (currently 3)
# We expect to fail *at* that limit, because we use up some of
# the stack depth limit in the test suite code
# So we check the expected limit and 75% of that
# XXX (ncoghlan): duplicating the scaling factor here is a little
# ugly. Perhaps it should be exposed somewhere...
fail_depth = sys.getrecursionlimit() * 3
crash_depth = sys.getrecursionlimit() * 300
success_depth = int(fail_depth * 0.75)
def check_limit(prefix, repeated, mode="single"):
expect_ok = prefix + repeated * success_depth
compile(expect_ok, '<test>', mode)
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):
compile(broken, '<test>', mode)
check_limit("a", "()")
check_limit("a", ".b")
check_limit("a", "[0]")
check_limit("a", "*a")
# XXX Crashes in the parser.
# check_limit("a", " if a else a")
# check_limit("if a: pass", "\nelif a: pass", mode="exec")
def test_null_terminated(self):
# The source code is null-terminated internally, but bytes-like
# objects are accepted, which could be not terminated.
with self.assertRaisesRegex(ValueError, "cannot contain null"):
compile("123\x00", "<dummy>", "eval")
with self.assertRaisesRegex(ValueError, "cannot contain null"):
compile(memoryview(b"123\x00"), "<dummy>", "eval")
code = compile(memoryview(b"123\x00")[1:-1], "<dummy>", "eval")
self.assertEqual(eval(code), 23)
code = compile(memoryview(b"1234")[1:-1], "<dummy>", "eval")
self.assertEqual(eval(code), 23)
code = compile(memoryview(b"$23$")[1:-1], "<dummy>", "eval")
self.assertEqual(eval(code), 23)
# Also test when eval() and exec() do the compilation step
self.assertEqual(eval(memoryview(b"1234")[1:-1]), 23)
namespace = dict()
exec(memoryview(b"ax = 123")[1:-1], namespace)
self.assertEqual(namespace['x'], 12)
def check_constant(self, func, expected):
for const in func.__code__.co_consts:
if repr(const) == repr(expected):
break
else:
self.fail("unable to find constant %r in %r"
% (expected, func.__code__.co_consts))
# Merging equal constants is not a strict requirement for the Python
# semantics, it's a more an implementation detail.
@support.cpython_only
def test_merge_constants(self):
# Issue #25843: compile() must merge constants which are equal
# and have the same type.
def check_same_constant(const):
ns = {}
code = "f1, f2 = lambda: %r, lambda: %r" % (const, const)
exec(code, ns)
f1 = ns['f1']
f2 = ns['f2']
self.assertIs(f1.__code__, f2.__code__)
self.check_constant(f1, const)
self.assertEqual(repr(f1()), repr(const))
check_same_constant(None)
check_same_constant(0)
check_same_constant(0.0)
check_same_constant(b'abc')
check_same_constant('abc')
# Note: "lambda: ..." emits "LOAD_CONST Ellipsis",
# whereas "lambda: Ellipsis" emits "LOAD_GLOBAL Ellipsis"
f1, f2 = lambda: ..., lambda: ...
self.assertIs(f1.__code__, f2.__code__)
self.check_constant(f1, Ellipsis)
self.assertEqual(repr(f1()), repr(Ellipsis))
# Merge constants in tuple or frozenset
f1, f2 = lambda: "not a name", lambda: ("not a name",)
f3 = lambda x: x in {("not a name",)}
self.assertIs(f1.__code__.co_consts[1],
f2.__code__.co_consts[1][0])
self.assertIs(next(iter(f3.__code__.co_consts[1])),
f2.__code__.co_consts[1])
# {0} is converted to a constant frozenset({0}) by the peephole
# optimizer
f1, f2 = lambda x: x in {0}, lambda x: x in {0}
self.assertIs(f1.__code__, f2.__code__)
self.check_constant(f1, frozenset({0}))
self.assertTrue(f1(0))
# Merging equal co_linetable is not a strict requirement
# for the Python semantics, it's a more an implementation detail.
@support.cpython_only
def test_merge_code_attrs(self):
# See https://bugs.python.org/issue42217
f1 = lambda x: x.y.z
f2 = lambda a: a.b.c
self.assertIs(f1.__code__.co_linetable, f2.__code__.co_linetable)
# Stripping unused constants is not a strict requirement for the
# Python semantics, it's a more an implementation detail.
@support.cpython_only
def test_strip_unused_consts(self):
# Python 3.10rc1 appended None to co_consts when None is not used
# at all. See bpo-45056.
def f1():
"docstring"
return 42
self.assertEqual(f1.__code__.co_consts, ("docstring", 42))
# This is a regression test for a CPython specific peephole optimizer
# implementation bug present in a few releases. It's assertion verifies
# that peephole optimization was actually done though that isn't an
# indication of the bugs presence or not (crashing is).
@support.cpython_only
def test_peephole_opt_unreachable_code_array_access_in_bounds(self):
"""Regression test for issue35193 when run under clang msan."""
def unused_code_at_end():
return 3
raise RuntimeError("unreachable")
# The above function definition will trigger the out of bounds
# bug in the peephole optimizer as it scans opcodes past the
# RETURN_VALUE opcode. This does not always crash an interpreter.
# When you build with the clang memory sanitizer it reliably aborts.
self.assertEqual(
'RETURN_VALUE',
list(dis.get_instructions(unused_code_at_end))[-1].opname)
def test_dont_merge_constants(self):
# Issue #25843: compile() must not merge constants which are equal
# but have a different type.
def check_different_constants(const1, const2):
ns = {}
exec("f1, f2 = lambda: %r, lambda: %r" % (const1, const2), ns)
f1 = ns['f1']
f2 = ns['f2']
self.assertIsNot(f1.__code__, f2.__code__)
self.assertNotEqual(f1.__code__, f2.__code__)
self.check_constant(f1, const1)
self.check_constant(f2, const2)
self.assertEqual(repr(f1()), repr(const1))
self.assertEqual(repr(f2()), repr(const2))
check_different_constants(0, 0.0)
check_different_constants(+0.0, -0.0)
check_different_constants((0,), (0.0,))
check_different_constants('a', b'a')
check_different_constants(('a',), (b'a',))
# check_different_constants() cannot be used because repr(-0j) is
# '(-0-0j)', but when '(-0-0j)' is evaluated to 0j: we loose the sign.
f1, f2 = lambda: +0.0j, lambda: -0.0j
self.assertIsNot(f1.__code__, f2.__code__)
self.check_constant(f1, +0.0j)
self.check_constant(f2, -0.0j)
self.assertEqual(repr(f1()), repr(+0.0j))
self.assertEqual(repr(f2()), repr(-0.0j))
# {0} is converted to a constant frozenset({0}) by the peephole
# optimizer
f1, f2 = lambda x: x in {0}, lambda x: x in {0.0}
self.assertIsNot(f1.__code__, f2.__code__)
self.check_constant(f1, frozenset({0}))
self.check_constant(f2, frozenset({0.0}))
self.assertTrue(f1(0))
self.assertTrue(f2(0.0))
def test_path_like_objects(self):
# An implicit test for PyUnicode_FSDecoder().
compile("42", FakePath("test_compile_pathlike"), "single")
def test_stack_overflow(self):
# bpo-31113: Stack overflow when compile a long sequence of
# complex statements.
compile("if a: b\n" * 200000, "<dummy>", "exec")
# Multiple users rely on the fact that CPython does not generate
# bytecode for dead code blocks. See bpo-37500 for more context.
@support.cpython_only
def test_dead_blocks_do_not_generate_bytecode(self):
def unused_block_if():
if 0:
return 42
def unused_block_while():
while 0:
return 42
def unused_block_if_else():
if 1:
return None
else:
return 42
def unused_block_while_else():
while 1:
return None
else:
return 42
funcs = [unused_block_if, unused_block_while,
unused_block_if_else, unused_block_while_else]
for func in funcs:
opcodes = list(dis.get_instructions(func))
self.assertLessEqual(len(opcodes), 4)
self.assertEqual('LOAD_CONST', opcodes[-2].opname)
self.assertEqual(None, opcodes[-2].argval)
self.assertEqual('RETURN_VALUE', opcodes[-1].opname)
def test_false_while_loop(self):
def break_in_while():
while False:
break
def continue_in_while():
while False:
continue
funcs = [break_in_while, continue_in_while]
# Check that we did not raise but we also don't generate bytecode
for func in funcs:
opcodes = list(dis.get_instructions(func))
self.assertEqual(3, len(opcodes))
self.assertEqual('LOAD_CONST', opcodes[1].opname)
self.assertEqual(None, opcodes[1].argval)
self.assertEqual('RETURN_VALUE', opcodes[2].opname)
def test_consts_in_conditionals(self):
def and_true(x):
return True and x
def and_false(x):
return False and x
def or_true(x):
return True or x
def or_false(x):
return False or x
funcs = [and_true, and_false, or_true, or_false]
# Check that condition is removed.
for func in funcs:
with self.subTest(func=func):
opcodes = list(dis.get_instructions(func))
self.assertLessEqual(len(opcodes), 3)
self.assertIn('LOAD_', opcodes[-2].opname)
self.assertEqual('RETURN_VALUE', opcodes[-1].opname)
def test_imported_load_method(self):
sources = [
"""\
import os
def foo():
return os.uname()
""",
"""\
import os as operating_system
def foo():
return operating_system.uname()
""",
"""\
from os import path
def foo(x):
return path.join(x)
""",
"""\
from os import path as os_path
def foo(x):
return os_path.join(x)
"""
]
for source in sources:
namespace = {}
exec(textwrap.dedent(source), namespace)
func = namespace['foo']
with self.subTest(func=func.__name__):
opcodes = list(dis.get_instructions(func))
instructions = [opcode.opname for opcode in opcodes]
self.assertNotIn('LOAD_METHOD', instructions)
self.assertIn('LOAD_ATTR', instructions)
self.assertIn('PRECALL', instructions)
def test_lineno_procedure_call(self):
def call():
(
print()
)
line1 = call.__code__.co_firstlineno + 1
assert line1 not in [line for (_, _, line) in call.__code__.co_lines()]
def test_lineno_after_implicit_return(self):
TRUE = True
# Don't use constant True or False, as compiler will remove test
def if1(x):
x()
if TRUE:
pass
def if2(x):
x()
if TRUE:
pass
else:
pass
def if3(x):
x()
if TRUE:
pass
else:
return None
def if4(x):
x()
if not TRUE:
pass
funcs = [ if1, if2, if3, if4]
lastlines = [ 3, 3, 3, 2]
frame = None
def save_caller_frame():
nonlocal frame
frame = sys._getframe(1)
for func, lastline in zip(funcs, lastlines, strict=True):
with self.subTest(func=func):
func(save_caller_frame)
self.assertEqual(frame.f_lineno-frame.f_code.co_firstlineno, lastline)
def test_lineno_after_no_code(self):
def no_code1():
"doc string"
def no_code2():
a: int
for func in (no_code1, no_code2):
with self.subTest(func=func):
code = func.__code__
lines = list(code.co_lines())
start, end, line = lines[0]
self.assertEqual(start, 0)
self.assertEqual(line, code.co_firstlineno)
def get_code_lines(self, code):
last_line = -2
res = []
for _, _, line in code.co_lines():
if line is not None and line != last_line:
res.append(line - code.co_firstlineno)
last_line = line
return res
def test_lineno_attribute(self):
def load_attr():
return (
o.
a
)
load_attr_lines = [ 0, 2, 3, 1 ]
def load_method():
return (
o.
m(
0
)
)
load_method_lines = [ 0, 2, 3, 4, 3, 1 ]
def store_attr():
(
o.
a
) = (
v
)
store_attr_lines = [ 0, 5, 2, 3 ]
def aug_store_attr():
(
o.
a
) += (
v
)
aug_store_attr_lines = [ 0, 2, 3, 5, 1, 3 ]
funcs = [ load_attr, load_method, store_attr, aug_store_attr]
func_lines = [ load_attr_lines, load_method_lines,
store_attr_lines, aug_store_attr_lines]
for func, lines in zip(funcs, func_lines, strict=True):
with self.subTest(func=func):
code_lines = self.get_code_lines(func.__code__)
self.assertEqual(lines, code_lines)
def test_line_number_genexp(self):
def return_genexp():
return (1
for
x
in
y)
genexp_lines = [0, 2, 0]
genexp_code = return_genexp.__code__.co_consts[1]
code_lines = self.get_code_lines(genexp_code)
self.assertEqual(genexp_lines, code_lines)
def test_line_number_implicit_return_after_async_for(self):
async def test(aseq):
async for i in aseq:
body
expected_lines = [0, 1, 2, 1]
code_lines = self.get_code_lines(test.__code__)
self.assertEqual(expected_lines, code_lines)
def test_big_dict_literal(self):
# The compiler has a flushing point in "compiler_dict" that calls compiles
# a portion of the dictionary literal when the loop that iterates over the items
# reaches 0xFFFF elements but the code was not including the boundary element,
# dropping the key at position 0xFFFF. See bpo-41531 for more information
dict_size = 0xFFFF + 1
the_dict = "{" + ",".join(f"{x}:{x}" for x in range(dict_size)) + "}"
self.assertEqual(len(eval(the_dict)), dict_size)
def test_redundant_jump_in_if_else_break(self):
# Check if bytecode containing jumps that simply point to the next line
# is generated around if-else-break style structures. See bpo-42615.
def if_else_break():
val = 1
while True:
if val > 0:
val -= 1
else:
break
val = -1
INSTR_SIZE = 2
HANDLED_JUMPS = (
'POP_JUMP_IF_FALSE',
'POP_JUMP_IF_TRUE',
'JUMP_ABSOLUTE',
'JUMP_FORWARD',
)
for line, instr in enumerate(
dis.Bytecode(if_else_break, show_caches=True)
):
if instr.opname == 'JUMP_FORWARD':
self.assertNotEqual(instr.arg, 0)
elif instr.opname in HANDLED_JUMPS:
self.assertNotEqual(instr.arg, (line + 1)*INSTR_SIZE)
def test_no_wraparound_jump(self):
# See https://bugs.python.org/issue46724
def while_not_chained(a, b, c):
while not (a < b < c):
pass
for instr in dis.Bytecode(while_not_chained):
self.assertNotEqual(instr.opname, "EXTENDED_ARG")
@requires_debug_ranges()
class TestSourcePositions(unittest.TestCase):
# Ensure that compiled code snippets have correct line and column numbers
# in `co_positions()`.
def check_positions_against_ast(self, snippet):
# Basic check that makes sure each line and column is at least present
# in one of the AST nodes of the source code.
code = compile(snippet, 'test_compile.py', 'exec')
ast_tree = compile(snippet, 'test_compile.py', 'exec', _ast.PyCF_ONLY_AST)
self.assertTrue(type(ast_tree) == _ast.Module)
# Use an AST visitor that notes all the offsets.
lines, end_lines, columns, end_columns = set(), set(), set(), set()
class SourceOffsetVisitor(ast.NodeVisitor):
def generic_visit(self, node):
super().generic_visit(node)
if not isinstance(node, ast.expr) and not isinstance(node, ast.stmt):
return
lines.add(node.lineno)
end_lines.add(node.end_lineno)
columns.add(node.col_offset)
end_columns.add(node.end_col_offset)
SourceOffsetVisitor().visit(ast_tree)
# Check against the positions in the code object.
for (line, end_line, col, end_col) in code.co_positions():
# If the offset is not None (indicating missing data), ensure that
# it was part of one of the AST nodes.
if line is not None:
self.assertIn(line, lines)
if end_line is not None:
self.assertIn(end_line, end_lines)
if col is not None:
self.assertIn(col, columns)
if end_col is not None:
self.assertIn(end_col, end_columns)
return code, ast_tree
def assertOpcodeSourcePositionIs(self, code, opcode,
line, end_line, column, end_column, occurrence=1):
for instr, position in zip(
dis.Bytecode(code, show_caches=True), code.co_positions(), strict=True
):
if instr.opname == opcode:
occurrence -= 1
if not occurrence:
self.assertEqual(position[0], line)
self.assertEqual(position[1], end_line)
self.assertEqual(position[2], column)
self.assertEqual(position[3], end_column)
return
self.fail(f"Opcode {opcode} not found in code")
def test_simple_assignment(self):
snippet = "x = 1"
self.check_positions_against_ast(snippet)
def test_compiles_to_extended_op_arg(self):
# Make sure we still have valid positions when the code compiles to an
# EXTENDED_ARG by performing a loop which needs a JUMP_ABSOLUTE after
# a bunch of opcodes.
snippet = "x = x\n" * 10_000
snippet += ("while x != 0:\n"
" x -= 1\n"
"while x != 0:\n"
" x += 1\n"
)
compiled_code, _ = self.check_positions_against_ast(snippet)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=10_000 + 2, end_line=10_000 + 2,
column=2, end_column=8, occurrence=1)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=10_000 + 4, end_line=10_000 + 4,
column=2, end_column=9, occurrence=2)
def test_multiline_expression(self):
snippet = """\
f(
1, 2, 3, 4
)
"""
compiled_code, _ = self.check_positions_against_ast(snippet)
self.assertOpcodeSourcePositionIs(compiled_code, 'CALL',
line=1, end_line=3, column=0, end_column=1)
def test_very_long_line_end_offset(self):
# Make sure we get the correct column offset for offsets
# too large to store in a byte.
long_string = "a" * 1000
snippet = f"g('{long_string}')"
compiled_code, _ = self.check_positions_against_ast(snippet)
self.assertOpcodeSourcePositionIs(compiled_code, 'CALL',
line=1, end_line=1, column=0, end_column=1005)
def test_complex_single_line_expression(self):
snippet = "a - b @ (c * x['key'] + 23)"
compiled_code, _ = self.check_positions_against_ast(snippet)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_SUBSCR',
line=1, end_line=1, column=13, end_column=21)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=1, end_line=1, column=9, end_column=21, occurrence=1)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=1, end_line=1, column=9, end_column=26, occurrence=2)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=1, end_line=1, column=4, end_column=27, occurrence=3)
self.assertOpcodeSourcePositionIs(compiled_code, 'BINARY_OP',
line=1, end_line=1, column=0, end_column=27, occurrence=4)
class TestExpressionStackSize(unittest.TestCase):
# These tests check that the computed stack size for a code object
# stays within reasonable bounds (see issue #21523 for an example
# dysfunction).
N = 100
def check_stack_size(self, code):
# To assert that the alleged stack size is not O(N), we
# check that it is smaller than log(N).
if isinstance(code, str):
code = compile(code, "<foo>", "single")
max_size = math.ceil(math.log(len(code.co_code)))
self.assertLessEqual(code.co_stacksize, max_size)
def test_and(self):
self.check_stack_size("x and " * self.N + "x")
def test_or(self):
self.check_stack_size("x or " * self.N + "x")
def test_and_or(self):
self.check_stack_size("x and x or " * self.N + "x")
def test_chained_comparison(self):
self.check_stack_size("x < " * self.N + "x")
def test_if_else(self):
self.check_stack_size("x if x else " * self.N + "x")
def test_binop(self):
self.check_stack_size("x + " * self.N + "x")
def test_list(self):
self.check_stack_size("[" + "x, " * self.N + "x]")
def test_tuple(self):
self.check_stack_size("(" + "x, " * self.N + "x)")
def test_set(self):
self.check_stack_size("{" + "x, " * self.N + "x}")
def test_dict(self):
self.check_stack_size("{" + "x:x, " * self.N + "x:x}")
def test_func_args(self):
self.check_stack_size("f(" + "x, " * self.N + ")")
def test_func_kwargs(self):
kwargs = (f'a{i}=x' for i in range(self.N))
self.check_stack_size("f(" + ", ".join(kwargs) + ")")
def test_meth_args(self):
self.check_stack_size("o.m(" + "x, " * self.N + ")")
def test_meth_kwargs(self):
kwargs = (f'a{i}=x' for i in range(self.N))
self.check_stack_size("o.m(" + ", ".join(kwargs) + ")")
def test_func_and(self):
code = "def f(x):\n"
code += " x and x\n" * self.N
self.check_stack_size(code)
class TestStackSizeStability(unittest.TestCase):
# Check that repeating certain snippets doesn't increase the stack size
# beyond what a single snippet requires.
def check_stack_size(self, snippet, async_=False):
def compile_snippet(i):
ns = {}
script = """def func():\n""" + i * snippet
if async_:
script = "async " + script
code = compile(script, "<script>", "exec")
exec(code, ns, ns)
return ns['func'].__code__
sizes = [compile_snippet(i).co_stacksize for i in range(2, 5)]
if len(set(sizes)) != 1:
import dis, io
out = io.StringIO()
dis.dis(compile_snippet(1), file=out)
self.fail("stack sizes diverge with # of consecutive snippets: "
"%s\n%s\n%s" % (sizes, snippet, out.getvalue()))
def test_if(self):
snippet = """
if x:
a
"""
self.check_stack_size(snippet)
def test_if_else(self):
snippet = """
if x:
a
elif y:
b
else:
c
"""
self.check_stack_size(snippet)
def test_try_except_bare(self):
snippet = """
try:
a
except:
b
"""
self.check_stack_size(snippet)
def test_try_except_qualified(self):
snippet = """
try:
a
except ImportError:
b
except:
c
else:
d
"""
self.check_stack_size(snippet)
def test_try_except_as(self):
snippet = """
try:
a
except ImportError as e:
b
except:
c
else:
d
"""
self.check_stack_size(snippet)
def test_try_except_star_qualified(self):
snippet = """
try:
a
except* ImportError:
b
else:
c
"""
self.check_stack_size(snippet)
def test_try_except_star_as(self):
snippet = """
try:
a
except* ImportError as e:
b
else:
c
"""
self.check_stack_size(snippet)
def test_try_except_star_finally(self):
snippet = """
try:
a
except* A:
b
finally:
c
"""
self.check_stack_size(snippet)
def test_try_finally(self):
snippet = """
try:
a
finally:
b
"""
self.check_stack_size(snippet)
def test_with(self):
snippet = """
with x as y:
a
"""
self.check_stack_size(snippet)
def test_while_else(self):
snippet = """
while x:
a
else:
b
"""
self.check_stack_size(snippet)
def test_for(self):
snippet = """
for x in y:
a
"""
self.check_stack_size(snippet)
def test_for_else(self):
snippet = """
for x in y:
a
else:
b
"""
self.check_stack_size(snippet)
def test_for_break_continue(self):
snippet = """
for x in y:
if z:
break
elif u:
continue
else:
a
else:
b
"""
self.check_stack_size(snippet)
def test_for_break_continue_inside_try_finally_block(self):
snippet = """
for x in y:
try:
if z:
break
elif u:
continue
else:
a
finally:
f
else:
b
"""
self.check_stack_size(snippet)
def test_for_break_continue_inside_finally_block(self):
snippet = """
for x in y:
try:
t
finally:
if z:
break
elif u:
continue
else:
a
else:
b
"""
self.check_stack_size(snippet)
def test_for_break_continue_inside_except_block(self):
snippet = """
for x in y:
try:
t
except:
if z:
break
elif u:
continue
else:
a
else:
b
"""
self.check_stack_size(snippet)
def test_for_break_continue_inside_with_block(self):
snippet = """
for x in y:
with c:
if z:
break
elif u:
continue
else:
a
else:
b
"""
self.check_stack_size(snippet)
def test_return_inside_try_finally_block(self):
snippet = """
try:
if z:
return
else:
a
finally:
f
"""
self.check_stack_size(snippet)
def test_return_inside_finally_block(self):
snippet = """
try:
t
finally:
if z:
return
else:
a
"""
self.check_stack_size(snippet)
def test_return_inside_except_block(self):
snippet = """
try:
t
except:
if z:
return
else:
a
"""
self.check_stack_size(snippet)
def test_return_inside_with_block(self):
snippet = """
with c:
if z:
return
else:
a
"""
self.check_stack_size(snippet)
def test_async_with(self):
snippet = """
async with x as y:
a
"""
self.check_stack_size(snippet, async_=True)
def test_async_for(self):
snippet = """
async for x in y:
a
"""
self.check_stack_size(snippet, async_=True)
def test_async_for_else(self):
snippet = """
async for x in y:
a
else:
b
"""
self.check_stack_size(snippet, async_=True)
def test_for_break_continue_inside_async_with_block(self):
snippet = """
for x in y:
async with c:
if z:
break
elif u:
continue
else:
a
else:
b
"""
self.check_stack_size(snippet, async_=True)
def test_return_inside_async_with_block(self):
snippet = """
async with c:
if z:
return
else:
a
"""
self.check_stack_size(snippet, async_=True)
if __name__ == "__main__":
unittest.main()