CasperSecurity
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
Test cases for the L{twisted.python.reflect} module.
"""
import os
import weakref
from collections import deque
from twisted.python import reflect
from twisted.python.reflect import (
accumulateMethods,
addMethodNamesToDict,
fullyQualifiedName,
prefixedMethodNames,
prefixedMethods,
)
from twisted.trial.unittest import SynchronousTestCase as TestCase
class Base:
"""
A no-op class which can be used to verify the behavior of
method-discovering APIs.
"""
def method(self):
"""
A no-op method which can be discovered.
"""
class Sub(Base):
"""
A subclass of a class with a method which can be discovered.
"""
class Separate:
"""
A no-op class with methods with differing prefixes.
"""
def good_method(self):
"""
A no-op method which a matching prefix to be discovered.
"""
def bad_method(self):
"""
A no-op method with a mismatched prefix to not be discovered.
"""
class AccumulateMethodsTests(TestCase):
"""
Tests for L{accumulateMethods} which finds methods on a class hierarchy and
adds them to a dictionary.
"""
def test_ownClass(self):
"""
If x is and instance of Base and Base defines a method named method,
L{accumulateMethods} adds an item to the given dictionary with
C{"method"} as the key and a bound method object for Base.method value.
"""
x = Base()
output = {}
accumulateMethods(x, output)
self.assertEqual({"method": x.method}, output)
def test_baseClass(self):
"""
If x is an instance of Sub and Sub is a subclass of Base and Base
defines a method named method, L{accumulateMethods} adds an item to the
given dictionary with C{"method"} as the key and a bound method object
for Base.method as the value.
"""
x = Sub()
output = {}
accumulateMethods(x, output)
self.assertEqual({"method": x.method}, output)
def test_prefix(self):
"""
If a prefix is given, L{accumulateMethods} limits its results to
methods beginning with that prefix. Keys in the resulting dictionary
also have the prefix removed from them.
"""
x = Separate()
output = {}
accumulateMethods(x, output, "good_")
self.assertEqual({"method": x.good_method}, output)
class PrefixedMethodsTests(TestCase):
"""
Tests for L{prefixedMethods} which finds methods on a class hierarchy and
adds them to a dictionary.
"""
def test_onlyObject(self):
"""
L{prefixedMethods} returns a list of the methods discovered on an
object.
"""
x = Base()
output = prefixedMethods(x)
self.assertEqual([x.method], output)
def test_prefix(self):
"""
If a prefix is given, L{prefixedMethods} returns only methods named
with that prefix.
"""
x = Separate()
output = prefixedMethods(x, "good_")
self.assertEqual([x.good_method], output)
class PrefixedMethodNamesTests(TestCase):
"""
Tests for L{prefixedMethodNames}.
"""
def test_method(self):
"""
L{prefixedMethodNames} returns a list including methods with the given
prefix defined on the class passed to it.
"""
self.assertEqual(["method"], prefixedMethodNames(Separate, "good_"))
def test_inheritedMethod(self):
"""
L{prefixedMethodNames} returns a list included methods with the given
prefix defined on base classes of the class passed to it.
"""
class Child(Separate):
pass
self.assertEqual(["method"], prefixedMethodNames(Child, "good_"))
class AddMethodNamesToDictTests(TestCase):
"""
Tests for L{addMethodNamesToDict}.
"""
def test_baseClass(self):
"""
If C{baseClass} is passed to L{addMethodNamesToDict}, only methods which
are a subclass of C{baseClass} are added to the result dictionary.
"""
class Alternate:
pass
class Child(Separate, Alternate):
def good_alternate(self):
pass
result = {}
addMethodNamesToDict(Child, result, "good_", Alternate)
self.assertEqual({"alternate": 1}, result)
class Summer:
"""
A class we look up as part of the LookupsTests.
"""
def reallySet(self):
"""
Do something.
"""
class LookupsTests(TestCase):
"""
Tests for L{namedClass}, L{namedModule}, and L{namedAny}.
"""
def test_namedClassLookup(self):
"""
L{namedClass} should return the class object for the name it is passed.
"""
self.assertIs(reflect.namedClass("twisted.test.test_reflect.Summer"), Summer)
def test_namedModuleLookup(self):
"""
L{namedModule} should return the module object for the name it is
passed.
"""
from twisted.python import monkey
self.assertIs(reflect.namedModule("twisted.python.monkey"), monkey)
def test_namedAnyPackageLookup(self):
"""
L{namedAny} should return the package object for the name it is passed.
"""
import twisted.python
self.assertIs(reflect.namedAny("twisted.python"), twisted.python)
def test_namedAnyModuleLookup(self):
"""
L{namedAny} should return the module object for the name it is passed.
"""
from twisted.python import monkey
self.assertIs(reflect.namedAny("twisted.python.monkey"), monkey)
def test_namedAnyClassLookup(self):
"""
L{namedAny} should return the class object for the name it is passed.
"""
self.assertIs(reflect.namedAny("twisted.test.test_reflect.Summer"), Summer)
def test_namedAnyAttributeLookup(self):
"""
L{namedAny} should return the object an attribute of a non-module,
non-package object is bound to for the name it is passed.
"""
# Note - not assertIs because unbound method lookup creates a new
# object every time. This is a foolishness of Python's object
# implementation, not a bug in Twisted.
self.assertEqual(
reflect.namedAny("twisted.test.test_reflect.Summer.reallySet"),
Summer.reallySet,
)
def test_namedAnySecondAttributeLookup(self):
"""
L{namedAny} should return the object an attribute of an object which
itself was an attribute of a non-module, non-package object is bound to
for the name it is passed.
"""
self.assertIs(
reflect.namedAny("twisted.test.test_reflect." "Summer.reallySet.__doc__"),
Summer.reallySet.__doc__,
)
def test_importExceptions(self):
"""
Exceptions raised by modules which L{namedAny} causes to be imported
should pass through L{namedAny} to the caller.
"""
self.assertRaises(
ZeroDivisionError, reflect.namedAny, "twisted.test.reflect_helper_ZDE"
)
# Make sure that there is post-failed-import cleanup
self.assertRaises(
ZeroDivisionError, reflect.namedAny, "twisted.test.reflect_helper_ZDE"
)
self.assertRaises(
ValueError, reflect.namedAny, "twisted.test.reflect_helper_VE"
)
# Modules which themselves raise ImportError when imported should
# result in an ImportError
self.assertRaises(
ImportError, reflect.namedAny, "twisted.test.reflect_helper_IE"
)
def test_attributeExceptions(self):
"""
If segments on the end of a fully-qualified Python name represents
attributes which aren't actually present on the object represented by
the earlier segments, L{namedAny} should raise an L{AttributeError}.
"""
self.assertRaises(
AttributeError, reflect.namedAny, "twisted.nosuchmoduleintheworld"
)
# ImportError behaves somewhat differently between "import
# extant.nonextant" and "import extant.nonextant.nonextant", so test
# the latter as well.
self.assertRaises(
AttributeError, reflect.namedAny, "twisted.nosuch.modulein.theworld"
)
self.assertRaises(
AttributeError,
reflect.namedAny,
"twisted.test.test_reflect.Summer.nosuchattribute",
)
def test_invalidNames(self):
"""
Passing a name which isn't a fully-qualified Python name to L{namedAny}
should result in one of the following exceptions:
- L{InvalidName}: the name is not a dot-separated list of Python
objects
- L{ObjectNotFound}: the object doesn't exist
- L{ModuleNotFound}: the object doesn't exist and there is only one
component in the name
"""
err = self.assertRaises(
reflect.ModuleNotFound, reflect.namedAny, "nosuchmoduleintheworld"
)
self.assertEqual(str(err), "No module named 'nosuchmoduleintheworld'")
# This is a dot-separated list, but it isn't valid!
err = self.assertRaises(
reflect.ObjectNotFound, reflect.namedAny, "@#$@(#.!@(#!@#"
)
self.assertEqual(str(err), "'@#$@(#.!@(#!@#' does not name an object")
err = self.assertRaises(
reflect.ObjectNotFound, reflect.namedAny, "tcelfer.nohtyp.detsiwt"
)
self.assertEqual(str(err), "'tcelfer.nohtyp.detsiwt' does not name an object")
err = self.assertRaises(reflect.InvalidName, reflect.namedAny, "")
self.assertEqual(str(err), "Empty module name")
for invalidName in [".twisted", "twisted.", "twisted..python"]:
err = self.assertRaises(reflect.InvalidName, reflect.namedAny, invalidName)
self.assertEqual(
str(err),
"name must be a string giving a '.'-separated list of Python "
"identifiers, not %r" % (invalidName,),
)
def test_requireModuleImportError(self):
"""
When module import fails with ImportError it returns the specified
default value.
"""
for name in ["nosuchmtopodule", "no.such.module"]:
default = object()
result = reflect.requireModule(name, default=default)
self.assertIs(result, default)
def test_requireModuleDefaultNone(self):
"""
When module import fails it returns L{None} by default.
"""
result = reflect.requireModule("no.such.module")
self.assertIsNone(result)
def test_requireModuleRequestedImport(self):
"""
When module import succeed it returns the module and not the default
value.
"""
from twisted.python import monkey
default = object()
self.assertIs(
reflect.requireModule("twisted.python.monkey", default=default),
monkey,
)
class Breakable:
breakRepr = False
breakStr = False
def __str__(self) -> str:
if self.breakStr:
raise RuntimeError("str!")
else:
return "<Breakable>"
def __repr__(self) -> str:
if self.breakRepr:
raise RuntimeError("repr!")
else:
return "Breakable()"
class BrokenType(Breakable, type):
breakName = False
@property
def __name__(self):
if self.breakName:
raise RuntimeError("no name")
return "BrokenType"
BTBase = BrokenType("BTBase", (Breakable,), {"breakRepr": True, "breakStr": True})
class NoClassAttr(Breakable):
__class__ = property(lambda x: x.not_class) # type: ignore[assignment]
class SafeReprTests(TestCase):
"""
Tests for L{reflect.safe_repr} function.
"""
def test_workingRepr(self):
"""
L{reflect.safe_repr} produces the same output as C{repr} on a working
object.
"""
xs = ([1, 2, 3], b"a")
self.assertEqual(list(map(reflect.safe_repr, xs)), list(map(repr, xs)))
def test_brokenRepr(self):
"""
L{reflect.safe_repr} returns a string with class name, address, and
traceback when the repr call failed.
"""
b = Breakable()
b.breakRepr = True
bRepr = reflect.safe_repr(b)
self.assertIn("Breakable instance at 0x", bRepr)
# Check that the file is in the repr, but without the extension as it
# can be .py/.pyc
self.assertIn(os.path.splitext(__file__)[0], bRepr)
self.assertIn("RuntimeError: repr!", bRepr)
def test_brokenStr(self):
"""
L{reflect.safe_repr} isn't affected by a broken C{__str__} method.
"""
b = Breakable()
b.breakStr = True
self.assertEqual(reflect.safe_repr(b), repr(b))
def test_brokenClassRepr(self):
class X(BTBase):
breakRepr = True
reflect.safe_repr(X)
reflect.safe_repr(X())
def test_brokenReprIncludesID(self):
"""
C{id} is used to print the ID of the object in case of an error.
L{safe_repr} includes a traceback after a newline, so we only check
against the first line of the repr.
"""
class X(BTBase):
breakRepr = True
xRepr = reflect.safe_repr(X)
xReprExpected = f"<BrokenType instance at 0x{id(X):x} with repr error:"
self.assertEqual(xReprExpected, xRepr.split("\n")[0])
def test_brokenClassStr(self):
class X(BTBase):
breakStr = True
reflect.safe_repr(X)
reflect.safe_repr(X())
def test_brokenClassAttribute(self):
"""
If an object raises an exception when accessing its C{__class__}
attribute, L{reflect.safe_repr} uses C{type} to retrieve the class
object.
"""
b = NoClassAttr()
b.breakRepr = True
bRepr = reflect.safe_repr(b)
self.assertIn("NoClassAttr instance at 0x", bRepr)
self.assertIn(os.path.splitext(__file__)[0], bRepr)
self.assertIn("RuntimeError: repr!", bRepr)
def test_brokenClassNameAttribute(self):
"""
If a class raises an exception when accessing its C{__name__} attribute
B{and} when calling its C{__str__} implementation, L{reflect.safe_repr}
returns 'BROKEN CLASS' instead of the class name.
"""
class X(BTBase):
breakName = True
xRepr = reflect.safe_repr(X())
self.assertIn("<BROKEN CLASS AT 0x", xRepr)
self.assertIn(os.path.splitext(__file__)[0], xRepr)
self.assertIn("RuntimeError: repr!", xRepr)
class SafeStrTests(TestCase):
"""
Tests for L{reflect.safe_str} function.
"""
def test_workingStr(self):
x = [1, 2, 3]
self.assertEqual(reflect.safe_str(x), str(x))
def test_brokenStr(self):
b = Breakable()
b.breakStr = True
reflect.safe_str(b)
def test_workingAscii(self):
"""
L{safe_str} for C{str} with ascii-only data should return the
value unchanged.
"""
x = "a"
self.assertEqual(reflect.safe_str(x), "a")
def test_workingUtf8_3(self):
"""
L{safe_str} for C{bytes} with utf-8 encoded data should return
the value decoded into C{str}.
"""
x = b"t\xc3\xbcst"
self.assertEqual(reflect.safe_str(x), x.decode("utf-8"))
def test_brokenUtf8(self):
"""
Use str() for non-utf8 bytes: "b'non-utf8'"
"""
x = b"\xff"
xStr = reflect.safe_str(x)
self.assertEqual(xStr, str(x))
def test_brokenRepr(self):
b = Breakable()
b.breakRepr = True
reflect.safe_str(b)
def test_brokenClassStr(self):
class X(BTBase):
breakStr = True
reflect.safe_str(X)
reflect.safe_str(X())
def test_brokenClassRepr(self):
class X(BTBase):
breakRepr = True
reflect.safe_str(X)
reflect.safe_str(X())
def test_brokenClassAttribute(self):
"""
If an object raises an exception when accessing its C{__class__}
attribute, L{reflect.safe_str} uses C{type} to retrieve the class
object.
"""
b = NoClassAttr()
b.breakStr = True
bStr = reflect.safe_str(b)
self.assertIn("NoClassAttr instance at 0x", bStr)
self.assertIn(os.path.splitext(__file__)[0], bStr)
self.assertIn("RuntimeError: str!", bStr)
def test_brokenClassNameAttribute(self):
"""
If a class raises an exception when accessing its C{__name__} attribute
B{and} when calling its C{__str__} implementation, L{reflect.safe_str}
returns 'BROKEN CLASS' instead of the class name.
"""
class X(BTBase):
breakName = True
xStr = reflect.safe_str(X())
self.assertIn("<BROKEN CLASS AT 0x", xStr)
self.assertIn(os.path.splitext(__file__)[0], xStr)
self.assertIn("RuntimeError: str!", xStr)
class FilenameToModuleTests(TestCase):
"""
Test L{filenameToModuleName} detection.
"""
def setUp(self):
self.path = os.path.join(self.mktemp(), "fakepackage", "test")
os.makedirs(self.path)
with open(os.path.join(self.path, "__init__.py"), "w") as f:
f.write("")
with open(os.path.join(os.path.dirname(self.path), "__init__.py"), "w") as f:
f.write("")
def test_directory(self):
"""
L{filenameToModuleName} returns the correct module (a package) given a
directory.
"""
module = reflect.filenameToModuleName(self.path)
self.assertEqual(module, "fakepackage.test")
module = reflect.filenameToModuleName(self.path + os.path.sep)
self.assertEqual(module, "fakepackage.test")
def test_file(self):
"""
L{filenameToModuleName} returns the correct module given the path to
its file.
"""
module = reflect.filenameToModuleName(
os.path.join(self.path, "test_reflect.py")
)
self.assertEqual(module, "fakepackage.test.test_reflect")
def test_bytes(self):
"""
L{filenameToModuleName} returns the correct module given a C{bytes}
path to its file.
"""
module = reflect.filenameToModuleName(
os.path.join(self.path.encode("utf-8"), b"test_reflect.py")
)
# Module names are always native string:
self.assertEqual(module, "fakepackage.test.test_reflect")
class FullyQualifiedNameTests(TestCase):
"""
Test for L{fullyQualifiedName}.
"""
def _checkFullyQualifiedName(self, obj, expected):
"""
Helper to check that fully qualified name of C{obj} results to
C{expected}.
"""
self.assertEqual(fullyQualifiedName(obj), expected)
def test_package(self):
"""
L{fullyQualifiedName} returns the full name of a package and a
subpackage.
"""
import twisted
self._checkFullyQualifiedName(twisted, "twisted")
import twisted.python
self._checkFullyQualifiedName(twisted.python, "twisted.python")
def test_module(self):
"""
L{fullyQualifiedName} returns the name of a module inside a package.
"""
import twisted.python.compat
self._checkFullyQualifiedName(twisted.python.compat, "twisted.python.compat")
def test_class(self):
"""
L{fullyQualifiedName} returns the name of a class and its module.
"""
self._checkFullyQualifiedName(
FullyQualifiedNameTests, f"{__name__}.FullyQualifiedNameTests"
)
def test_function(self):
"""
L{fullyQualifiedName} returns the name of a function inside its module.
"""
self._checkFullyQualifiedName(
fullyQualifiedName, "twisted.python.reflect.fullyQualifiedName"
)
def test_boundMethod(self):
"""
L{fullyQualifiedName} returns the name of a bound method inside its
class and its module.
"""
self._checkFullyQualifiedName(
self.test_boundMethod,
f"{__name__}.{self.__class__.__name__}.test_boundMethod",
)
def test_unboundMethod(self):
"""
L{fullyQualifiedName} returns the name of an unbound method inside its
class and its module.
"""
self._checkFullyQualifiedName(
self.__class__.test_unboundMethod,
f"{__name__}.{self.__class__.__name__}.test_unboundMethod",
)
class ObjectGrepTests(TestCase):
def test_dictionary(self):
"""
Test references search through a dictionary, as a key or as a value.
"""
o = object()
d1 = {None: o}
d2 = {o: None}
self.assertIn("[None]", reflect.objgrep(d1, o, reflect.isSame))
self.assertIn("{None}", reflect.objgrep(d2, o, reflect.isSame))
def test_list(self):
"""
Test references search through a list.
"""
o = object()
L = [None, o]
self.assertIn("[1]", reflect.objgrep(L, o, reflect.isSame))
def test_tuple(self):
"""
Test references search through a tuple.
"""
o = object()
T = (o, None)
self.assertIn("[0]", reflect.objgrep(T, o, reflect.isSame))
def test_instance(self):
"""
Test references search through an object attribute.
"""
class Dummy:
pass
o = object()
d = Dummy()
d.o = o
self.assertIn(".o", reflect.objgrep(d, o, reflect.isSame))
def test_weakref(self):
"""
Test references search through a weakref object.
"""
class Dummy:
pass
o = Dummy()
w1 = weakref.ref(o)
self.assertIn("()", reflect.objgrep(w1, o, reflect.isSame))
def test_boundMethod(self):
"""
Test references search through method special attributes.
"""
class Dummy:
def dummy(self):
pass
o = Dummy()
m = o.dummy
self.assertIn(".__self__", reflect.objgrep(m, m.__self__, reflect.isSame))
self.assertIn(
".__self__.__class__",
reflect.objgrep(m, m.__self__.__class__, reflect.isSame),
)
self.assertIn(".__func__", reflect.objgrep(m, m.__func__, reflect.isSame))
def test_everything(self):
"""
Test references search using complex set of objects.
"""
class Dummy:
def method(self):
pass
o = Dummy()
D1 = {(): "baz", None: "Quux", o: "Foosh"}
L = [None, (), D1, 3]
T = (L, {}, Dummy())
D2 = {0: "foo", 1: "bar", 2: T}
i = Dummy()
i.attr = D2
m = i.method
w = weakref.ref(m)
self.assertIn(
"().__self__.attr[2][0][2]{'Foosh'}", reflect.objgrep(w, o, reflect.isSame)
)
def test_depthLimit(self):
"""
Test the depth of references search.
"""
a = []
b = [a]
c = [a, b]
d = [a, c]
self.assertEqual(["[0]"], reflect.objgrep(d, a, reflect.isSame, maxDepth=1))
self.assertEqual(
["[0]", "[1][0]"], reflect.objgrep(d, a, reflect.isSame, maxDepth=2)
)
self.assertEqual(
["[0]", "[1][0]", "[1][1][0]"],
reflect.objgrep(d, a, reflect.isSame, maxDepth=3),
)
def test_deque(self):
"""
Test references search through a deque object.
"""
o = object()
D = deque()
D.append(None)
D.append(o)
self.assertIn("[1]", reflect.objgrep(D, o, reflect.isSame))
class GetClassTests(TestCase):
def test_new(self):
class NewClass:
pass
new = NewClass()
self.assertEqual(reflect.getClass(NewClass).__name__, "type")
self.assertEqual(reflect.getClass(new).__name__, "NewClass")