"""This module includes tests of the code object representation. >>> def f(x): ... def g(y): ... return x + y ... return g ... >>> dump(f.__code__) name: f argcount: 1 posonlyargcount: 0 kwonlyargcount: 0 names: () varnames: ('x', 'g') cellvars: ('x',) freevars: () nlocals: 2 flags: 3 consts: ('None', '') >>> dump(f(4).__code__) name: g argcount: 1 posonlyargcount: 0 kwonlyargcount: 0 names: () varnames: ('y',) cellvars: () freevars: ('x',) nlocals: 1 flags: 19 consts: ('None',) >>> def h(x, y): ... a = x + y ... b = x - y ... c = a * b ... return c ... >>> dump(h.__code__) name: h argcount: 2 posonlyargcount: 0 kwonlyargcount: 0 names: () varnames: ('x', 'y', 'a', 'b', 'c') cellvars: () freevars: () nlocals: 5 flags: 3 consts: ('None',) >>> def attrs(obj): ... print(obj.attr1) ... print(obj.attr2) ... print(obj.attr3) >>> dump(attrs.__code__) name: attrs argcount: 1 posonlyargcount: 0 kwonlyargcount: 0 names: ('print', 'attr1', 'attr2', 'attr3') varnames: ('obj',) cellvars: () freevars: () nlocals: 1 flags: 3 consts: ('None',) >>> def optimize_away(): ... 'doc string' ... 'not a docstring' ... 53 ... 0x53 >>> dump(optimize_away.__code__) name: optimize_away argcount: 0 posonlyargcount: 0 kwonlyargcount: 0 names: () varnames: () cellvars: () freevars: () nlocals: 0 flags: 3 consts: ("'doc string'", 'None') >>> def keywordonly_args(a,b,*,k1): ... return a,b,k1 ... >>> dump(keywordonly_args.__code__) name: keywordonly_args argcount: 2 posonlyargcount: 0 kwonlyargcount: 1 names: () varnames: ('a', 'b', 'k1') cellvars: () freevars: () nlocals: 3 flags: 3 consts: ('None',) >>> def posonly_args(a,b,/,c): ... return a,b,c ... >>> dump(posonly_args.__code__) name: posonly_args argcount: 3 posonlyargcount: 2 kwonlyargcount: 0 names: () varnames: ('a', 'b', 'c') cellvars: () freevars: () nlocals: 3 flags: 3 consts: ('None',) """ import copy import inspect import sys import threading import doctest import unittest import textwrap import weakref import dis try: import ctypes except ImportError: ctypes = None from test.support import (cpython_only, check_impl_detail, requires_debug_ranges, gc_collect) from test.support.script_helper import assert_python_ok from test.support import threading_helper from test.support.bytecode_helper import (BytecodeTestCase, instructions_with_positions) from opcode import opmap, opname COPY_FREE_VARS = opmap['COPY_FREE_VARS'] def consts(t): """Yield a doctest-safe sequence of object reprs.""" for elt in t: r = repr(elt) if r.startswith("" % elt.co_name else: yield r def dump(co): """Print out a text representation of a code object.""" for attr in ["name", "argcount", "posonlyargcount", "kwonlyargcount", "names", "varnames", "cellvars", "freevars", "nlocals", "flags"]: print("%s: %s" % (attr, getattr(co, "co_" + attr))) print("consts:", tuple(consts(co.co_consts))) # Needed for test_closure_injection below # Defined at global scope to avoid implicitly closing over __class__ def external_getitem(self, i): return f"Foreign getitem: {super().__getitem__(i)}" class CodeTest(unittest.TestCase): @cpython_only def test_newempty(self): import _testcapi co = _testcapi.code_newempty("filename", "funcname", 15) self.assertEqual(co.co_filename, "filename") self.assertEqual(co.co_name, "funcname") self.assertEqual(co.co_firstlineno, 15) #Empty code object should raise, but not crash the VM with self.assertRaises(Exception): exec(co) @cpython_only def test_closure_injection(self): # From https://bugs.python.org/issue32176 from types import FunctionType def create_closure(__class__): return (lambda: __class__).__closure__ def new_code(c): '''A new code object with a __class__ cell added to freevars''' return c.replace(co_freevars=c.co_freevars + ('__class__',), co_code=bytes([COPY_FREE_VARS, 1])+c.co_code) def add_foreign_method(cls, name, f): code = new_code(f.__code__) assert not f.__closure__ closure = create_closure(cls) defaults = f.__defaults__ setattr(cls, name, FunctionType(code, globals(), name, defaults, closure)) class List(list): pass add_foreign_method(List, "__getitem__", external_getitem) # Ensure the closure injection actually worked function = List.__getitem__ class_ref = function.__closure__[0].cell_contents self.assertIs(class_ref, List) # Ensure the zero-arg super() call in the injected method works obj = List([1, 2, 3]) self.assertEqual(obj[0], "Foreign getitem: 1") def test_constructor(self): def func(): pass co = func.__code__ CodeType = type(co) # test code constructor CodeType(co.co_argcount, co.co_posonlyargcount, co.co_kwonlyargcount, co.co_nlocals, co.co_stacksize, co.co_flags, co.co_code, co.co_consts, co.co_names, co.co_varnames, co.co_filename, co.co_name, co.co_qualname, co.co_firstlineno, co.co_linetable, co.co_exceptiontable, co.co_freevars, co.co_cellvars) def test_qualname(self): self.assertEqual( CodeTest.test_qualname.__code__.co_qualname, CodeTest.test_qualname.__qualname__ ) def test_replace(self): def func(): x = 1 return x code = func.__code__ # different co_name, co_varnames, co_consts def func2(): y = 2 z = 3 return y code2 = func2.__code__ for attr, value in ( ("co_argcount", 0), ("co_posonlyargcount", 0), ("co_kwonlyargcount", 0), ("co_nlocals", 1), ("co_stacksize", 1), ("co_flags", code.co_flags | inspect.CO_COROUTINE), ("co_firstlineno", 100), ("co_code", code2.co_code), ("co_consts", code2.co_consts), ("co_names", ("myname",)), ("co_varnames", ('spam',)), ("co_freevars", ("freevar",)), ("co_cellvars", ("cellvar",)), ("co_filename", "newfilename"), ("co_name", "newname"), ("co_linetable", code2.co_linetable), ): with self.subTest(attr=attr, value=value): new_code = code.replace(**{attr: value}) self.assertEqual(getattr(new_code, attr), value) new_code = copy.replace(code, **{attr: value}) self.assertEqual(getattr(new_code, attr), value) new_code = code.replace(co_varnames=code2.co_varnames, co_nlocals=code2.co_nlocals) self.assertEqual(new_code.co_varnames, code2.co_varnames) self.assertEqual(new_code.co_nlocals, code2.co_nlocals) new_code = copy.replace(code, co_varnames=code2.co_varnames, co_nlocals=code2.co_nlocals) self.assertEqual(new_code.co_varnames, code2.co_varnames) self.assertEqual(new_code.co_nlocals, code2.co_nlocals) def test_nlocals_mismatch(self): def func(): x = 1 return x co = func.__code__ assert co.co_nlocals > 0; # First we try the constructor. CodeType = type(co) for diff in (-1, 1): with self.assertRaises(ValueError): CodeType(co.co_argcount, co.co_posonlyargcount, co.co_kwonlyargcount, # This is the only change. co.co_nlocals + diff, co.co_stacksize, co.co_flags, co.co_code, co.co_consts, co.co_names, co.co_varnames, co.co_filename, co.co_name, co.co_qualname, co.co_firstlineno, co.co_linetable, co.co_exceptiontable, co.co_freevars, co.co_cellvars, ) # Then we try the replace method. with self.assertRaises(ValueError): co.replace(co_nlocals=co.co_nlocals - 1) with self.assertRaises(ValueError): co.replace(co_nlocals=co.co_nlocals + 1) def test_shrinking_localsplus(self): # Check that PyCode_NewWithPosOnlyArgs resizes both # localsplusnames and localspluskinds, if an argument is a cell. def func(arg): return lambda: arg code = func.__code__ newcode = code.replace(co_name="func") # Should not raise SystemError self.assertEqual(code, newcode) def test_empty_linetable(self): def func(): pass new_code = code = func.__code__.replace(co_linetable=b'') self.assertEqual(list(new_code.co_lines()), []) def test_co_lnotab_is_deprecated(self): # TODO: remove in 3.14 def func(): pass with self.assertWarns(DeprecationWarning): func.__code__.co_lnotab def test_invalid_bytecode(self): def foo(): pass # assert that opcode 229 is invalid self.assertEqual(opname[229], '<229>') # change first opcode to 0xeb (=229) foo.__code__ = foo.__code__.replace( co_code=b'\xe5' + foo.__code__.co_code[1:]) msg = "unknown opcode 229" with self.assertRaisesRegex(SystemError, msg): foo() @requires_debug_ranges() def test_co_positions_artificial_instructions(self): import dis namespace = {} exec(textwrap.dedent("""\ try: 1/0 except Exception as e: exc = e """), namespace) exc = namespace['exc'] traceback = exc.__traceback__ code = traceback.tb_frame.f_code artificial_instructions = [] for instr, positions in instructions_with_positions( dis.get_instructions(code), code.co_positions() ): # If any of the positions is None, then all have to # be None as well for the case above. There are still # some places in the compiler, where the artificial instructions # get assigned the first_lineno but they don't have other positions. # There is no easy way of inferring them at that stage, so for now # we don't support it. self.assertIn(positions.count(None), [0, 3, 4]) if not any(positions): artificial_instructions.append(instr) self.assertEqual( [ (instruction.opname, instruction.argval) for instruction in artificial_instructions ], [ ("PUSH_EXC_INFO", None), ("LOAD_CONST", None), # artificial 'None' ("STORE_NAME", "e"), # XX: we know the location for this ("DELETE_NAME", "e"), ("RERAISE", 1), ("COPY", 3), ("POP_EXCEPT", None), ("RERAISE", 1) ] ) def test_endline_and_columntable_none_when_no_debug_ranges(self): # Make sure that if `-X no_debug_ranges` is used, there is # minimal debug info code = textwrap.dedent(""" def f(): pass positions = f.__code__.co_positions() for line, end_line, column, end_column in positions: assert line == end_line assert column is None assert end_column is None """) assert_python_ok('-X', 'no_debug_ranges', '-c', code) def test_endline_and_columntable_none_when_no_debug_ranges_env(self): # Same as above but using the environment variable opt out. code = textwrap.dedent(""" def f(): pass positions = f.__code__.co_positions() for line, end_line, column, end_column in positions: assert line == end_line assert column is None assert end_column is None """) assert_python_ok('-c', code, PYTHONNODEBUGRANGES='1') # co_positions behavior when info is missing. @requires_debug_ranges() def test_co_positions_empty_linetable(self): def func(): x = 1 new_code = func.__code__.replace(co_linetable=b'') positions = new_code.co_positions() for line, end_line, column, end_column in positions: self.assertIsNone(line) self.assertEqual(end_line, new_code.co_firstlineno + 1) def test_code_equality(self): def f(): try: a() except: b() else: c() finally: d() code_a = f.__code__ code_b = code_a.replace(co_linetable=b"") code_c = code_a.replace(co_exceptiontable=b"") code_d = code_b.replace(co_exceptiontable=b"") self.assertNotEqual(code_a, code_b) self.assertNotEqual(code_a, code_c) self.assertNotEqual(code_a, code_d) self.assertNotEqual(code_b, code_c) self.assertNotEqual(code_b, code_d) self.assertNotEqual(code_c, code_d) def test_code_hash_uses_firstlineno(self): c1 = (lambda: 1).__code__ c2 = (lambda: 1).__code__ self.assertNotEqual(c1, c2) self.assertNotEqual(hash(c1), hash(c2)) c3 = c1.replace(co_firstlineno=17) self.assertNotEqual(c1, c3) self.assertNotEqual(hash(c1), hash(c3)) def test_code_hash_uses_order(self): # Swapping posonlyargcount and kwonlyargcount should change the hash. c = (lambda x, y, *, z=1, w=1: 1).__code__ self.assertEqual(c.co_argcount, 2) self.assertEqual(c.co_posonlyargcount, 0) self.assertEqual(c.co_kwonlyargcount, 2) swapped = c.replace(co_posonlyargcount=2, co_kwonlyargcount=0) self.assertNotEqual(c, swapped) self.assertNotEqual(hash(c), hash(swapped)) def test_code_hash_uses_bytecode(self): c = (lambda x, y: x + y).__code__ d = (lambda x, y: x * y).__code__ c1 = c.replace(co_code=d.co_code) self.assertNotEqual(c, c1) self.assertNotEqual(hash(c), hash(c1)) @cpython_only def test_code_equal_with_instrumentation(self): """ GH-109052 Make sure the instrumentation doesn't affect the code equality The validity of this test relies on the fact that "x is x" and "x in x" have only one different instruction and the instructions have the same argument. """ code1 = compile("x is x", "example.py", "eval") code2 = compile("x in x", "example.py", "eval") sys._getframe().f_trace_opcodes = True sys.settrace(lambda *args: None) exec(code1, {'x': []}) exec(code2, {'x': []}) self.assertNotEqual(code1, code2) sys.settrace(None) def isinterned(s): return s is sys.intern(('_' + s + '_')[1:-1]) class CodeConstsTest(unittest.TestCase): def find_const(self, consts, value): for v in consts: if v == value: return v self.assertIn(value, consts) # raises an exception self.fail('Should never be reached') def assertIsInterned(self, s): if not isinterned(s): self.fail('String %r is not interned' % (s,)) def assertIsNotInterned(self, s): if isinterned(s): self.fail('String %r is interned' % (s,)) @cpython_only def test_interned_string(self): co = compile('res = "str_value"', '?', 'exec') v = self.find_const(co.co_consts, 'str_value') self.assertIsInterned(v) @cpython_only def test_interned_string_in_tuple(self): co = compile('res = ("str_value",)', '?', 'exec') v = self.find_const(co.co_consts, ('str_value',)) self.assertIsInterned(v[0]) @cpython_only def test_interned_string_in_frozenset(self): co = compile('res = a in {"str_value"}', '?', 'exec') v = self.find_const(co.co_consts, frozenset(('str_value',))) self.assertIsInterned(tuple(v)[0]) @cpython_only def test_interned_string_default(self): def f(a='str_value'): return a self.assertIsInterned(f()) @cpython_only def test_interned_string_with_null(self): co = compile(r'res = "str\0value!"', '?', 'exec') v = self.find_const(co.co_consts, 'str\0value!') self.assertIsNotInterned(v) class CodeWeakRefTest(unittest.TestCase): def test_basic(self): # Create a code object in a clean environment so that we know we have # the only reference to it left. namespace = {} exec("def f(): pass", globals(), namespace) f = namespace["f"] del namespace self.called = False def callback(code): self.called = True # f is now the last reference to the function, and through it, the code # object. While we hold it, check that we can create a weakref and # deref it. Then delete it, and check that the callback gets called and # the reference dies. coderef = weakref.ref(f.__code__, callback) self.assertTrue(bool(coderef())) del f gc_collect() # For PyPy or other GCs. self.assertFalse(bool(coderef())) self.assertTrue(self.called) # Python implementation of location table parsing algorithm def read(it): return next(it) def read_varint(it): b = read(it) val = b & 63; shift = 0; while b & 64: b = read(it) shift += 6 val |= (b&63) << shift return val def read_signed_varint(it): uval = read_varint(it) if uval & 1: return -(uval >> 1) else: return uval >> 1 def parse_location_table(code): line = code.co_firstlineno it = iter(code.co_linetable) while True: try: first_byte = read(it) except StopIteration: return code = (first_byte >> 3) & 15 length = (first_byte & 7) + 1 if code == 15: yield (code, length, None, None, None, None) elif code == 14: line_delta = read_signed_varint(it) line += line_delta end_line = line + read_varint(it) col = read_varint(it) if col == 0: col = None else: col -= 1 end_col = read_varint(it) if end_col == 0: end_col = None else: end_col -= 1 yield (code, length, line, end_line, col, end_col) elif code == 13: # No column line_delta = read_signed_varint(it) line += line_delta yield (code, length, line, line, None, None) elif code in (10, 11, 12): # new line line_delta = code - 10 line += line_delta column = read(it) end_column = read(it) yield (code, length, line, line, column, end_column) else: assert (0 <= code < 10) second_byte = read(it) column = code << 3 | (second_byte >> 4) yield (code, length, line, line, column, column + (second_byte & 15)) def positions_from_location_table(code): for _, length, line, end_line, col, end_col in parse_location_table(code): for _ in range(length): yield (line, end_line, col, end_col) def dedup(lst, prev=object()): for item in lst: if item != prev: yield item prev = item def lines_from_postions(positions): return dedup(l for (l, _, _, _) in positions) def misshappen(): """ """ x = ( 4 + y ) y = ( a + b + d ) return q if ( x ) else p def bug93662(): example_report_generation_message= ( """ """ ).strip() raise ValueError() class CodeLocationTest(unittest.TestCase): def check_positions(self, func): pos1 = list(func.__code__.co_positions()) pos2 = list(positions_from_location_table(func.__code__)) for l1, l2 in zip(pos1, pos2): self.assertEqual(l1, l2) self.assertEqual(len(pos1), len(pos2)) def test_positions(self): self.check_positions(parse_location_table) self.check_positions(misshappen) self.check_positions(bug93662) def check_lines(self, func): co = func.__code__ lines1 = [line for _, _, line in co.co_lines()] self.assertEqual(lines1, list(dedup(lines1))) lines2 = list(lines_from_postions(positions_from_location_table(co))) for l1, l2 in zip(lines1, lines2): self.assertEqual(l1, l2) self.assertEqual(len(lines1), len(lines2)) def test_lines(self): self.check_lines(parse_location_table) self.check_lines(misshappen) self.check_lines(bug93662) @cpython_only def test_code_new_empty(self): # If this test fails, it means that the construction of PyCode_NewEmpty # needs to be modified! Please update this test *and* PyCode_NewEmpty, # so that they both stay in sync. def f(): pass PY_CODE_LOCATION_INFO_NO_COLUMNS = 13 f.__code__ = f.__code__.replace( co_stacksize=1, co_firstlineno=42, co_code=bytes( [ dis.opmap["RESUME"], 0, dis.opmap["LOAD_ASSERTION_ERROR"], 0, dis.opmap["RAISE_VARARGS"], 1, ] ), co_linetable=bytes( [ (1 << 7) | (PY_CODE_LOCATION_INFO_NO_COLUMNS << 3) | (3 - 1), 0, ] ), ) self.assertRaises(AssertionError, f) self.assertEqual( list(f.__code__.co_positions()), 3 * [(42, 42, None, None)], ) if check_impl_detail(cpython=True) and ctypes is not None: py = ctypes.pythonapi freefunc = ctypes.CFUNCTYPE(None,ctypes.c_voidp) RequestCodeExtraIndex = py.PyUnstable_Eval_RequestCodeExtraIndex RequestCodeExtraIndex.argtypes = (freefunc,) RequestCodeExtraIndex.restype = ctypes.c_ssize_t SetExtra = py.PyUnstable_Code_SetExtra SetExtra.argtypes = (ctypes.py_object, ctypes.c_ssize_t, ctypes.c_voidp) SetExtra.restype = ctypes.c_int GetExtra = py.PyUnstable_Code_GetExtra GetExtra.argtypes = (ctypes.py_object, ctypes.c_ssize_t, ctypes.POINTER(ctypes.c_voidp)) GetExtra.restype = ctypes.c_int LAST_FREED = None def myfree(ptr): global LAST_FREED LAST_FREED = ptr FREE_FUNC = freefunc(myfree) FREE_INDEX = RequestCodeExtraIndex(FREE_FUNC) class CoExtra(unittest.TestCase): def get_func(self): # Defining a function causes the containing function to have a # reference to the code object. We need the code objects to go # away, so we eval a lambda. return eval('lambda:42') def test_get_non_code(self): f = self.get_func() self.assertRaises(SystemError, SetExtra, 42, FREE_INDEX, ctypes.c_voidp(100)) self.assertRaises(SystemError, GetExtra, 42, FREE_INDEX, ctypes.c_voidp(100)) def test_bad_index(self): f = self.get_func() self.assertRaises(SystemError, SetExtra, f.__code__, FREE_INDEX+100, ctypes.c_voidp(100)) self.assertEqual(GetExtra(f.__code__, FREE_INDEX+100, ctypes.c_voidp(100)), 0) def test_free_called(self): # Verify that the provided free function gets invoked # when the code object is cleaned up. f = self.get_func() SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(100)) del f self.assertEqual(LAST_FREED, 100) def test_get_set(self): # Test basic get/set round tripping. f = self.get_func() extra = ctypes.c_voidp() SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(200)) # reset should free... SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(300)) self.assertEqual(LAST_FREED, 200) extra = ctypes.c_voidp() GetExtra(f.__code__, FREE_INDEX, extra) self.assertEqual(extra.value, 300) del f @threading_helper.requires_working_threading() def test_free_different_thread(self): # Freeing a code object on a different thread then # where the co_extra was set should be safe. f = self.get_func() class ThreadTest(threading.Thread): def __init__(self, f, test): super().__init__() self.f = f self.test = test def run(self): del self.f self.test.assertEqual(LAST_FREED, 500) SetExtra(f.__code__, FREE_INDEX, ctypes.c_voidp(500)) tt = ThreadTest(f, self) del f tt.start() tt.join() self.assertEqual(LAST_FREED, 500) def load_tests(loader, tests, pattern): tests.addTest(doctest.DocTestSuite()) return tests if __name__ == "__main__": unittest.main()