Implement PEP 3115 -- new metaclass syntax and semantics.
The compiler package hasn't been updated yet; test_compiler.py fails.
Otherwise all tests seem to be passing now. There are no occurrences
of __metaclass__ left in the standard library.
Docs have not been updated.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index e8db29e..6cd8ccd 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -616,9 +616,8 @@
vereq(a[100:200], (100,200))
def metaclass():
- if verbose: print("Testing __metaclass__...")
- class C:
- __metaclass__ = type
+ if verbose: print("Testing metaclass...")
+ class C(metaclass=type):
def __init__(self):
self.__state = 0
def getstate(self):
@@ -629,9 +628,10 @@
vereq(a.getstate(), 0)
a.setstate(10)
vereq(a.getstate(), 10)
- class D:
- class __metaclass__(type):
- def myself(cls): return cls
+ class _metaclass(type):
+ def myself(cls): return cls
+ class D(metaclass=_metaclass):
+ pass
vereq(D.myself(), D)
d = D()
verify(d.__class__ is D)
@@ -639,8 +639,8 @@
def __new__(cls, name, bases, dict):
dict['__spam__'] = 1
return type.__new__(cls, name, bases, dict)
- class C:
- __metaclass__ = M1
+ class C(metaclass=M1):
+ pass
vereq(C.__spam__, 1)
c = C()
vereq(c.__spam__, 1)
@@ -663,8 +663,7 @@
continue
setattr(it, key, self.dict[key].__get__(it, self))
return it
- class C:
- __metaclass__ = M2
+ class C(metaclass=M2):
def spam(self):
return 42
vereq(C.name, 'C')
@@ -690,8 +689,7 @@
name = "__super"
setattr(cls, name, super(cls))
return cls
- class A:
- __metaclass__ = autosuper
+ class A(metaclass=autosuper):
def meth(self):
return "A"
class B(A):
@@ -729,8 +727,7 @@
dict[key] = property(get, set)
return super(autoproperty, metaclass).__new__(metaclass,
name, bases, dict)
- class A:
- __metaclass__ = autoproperty
+ class A(metaclass=autoproperty):
def _get_x(self):
return -self.__x
def _set_x(self, x):
@@ -744,8 +741,7 @@
class multimetaclass(autoproperty, autosuper):
# Merge of multiple cooperating metaclasses
pass
- class A:
- __metaclass__ = multimetaclass
+ class A(metaclass=multimetaclass):
def _get_x(self):
return "A"
class B(A):
@@ -764,8 +760,8 @@
counter = 0
def __init__(self, *args):
T.counter += 1
- class C:
- __metaclass__ = T
+ class C(metaclass=T):
+ pass
vereq(T.counter, 1)
a = C()
vereq(type(a), C)
@@ -1273,8 +1269,8 @@
# Test comparison of classes with dynamic metaclasses
class dynamicmetaclass(type):
pass
- class someclass:
- __metaclass__ = dynamicmetaclass
+ class someclass(metaclass=dynamicmetaclass):
+ pass
verify(someclass != object)
def errors():
@@ -1505,36 +1501,39 @@
L = type.mro(cls)
L.reverse()
return L
- class X(D,B,C,A):
- __metaclass__ = PerverseMetaType
+ class X(D,B,C,A, metaclass=PerverseMetaType):
+ pass
vereq(X.__mro__, (object, A, C, B, D, X))
vereq(X().f(), "A")
try:
- class X(object):
- class __metaclass__(type):
- def mro(self):
- return [self, dict, object]
+ class _metaclass(type):
+ def mro(self):
+ return [self, dict, object]
+ class X(object, metaclass=_metaclass):
+ pass
except TypeError:
pass
else:
raise TestFailed, "devious mro() return not caught"
try:
- class X(object):
- class __metaclass__(type):
- def mro(self):
- return [1]
+ class _metaclass(type):
+ def mro(self):
+ return [1]
+ class X(object, metaclass=_metaclass):
+ pass
except TypeError:
pass
else:
raise TestFailed, "non-class mro() return not caught"
try:
- class X(object):
- class __metaclass__(type):
- def mro(self):
- return 1
+ class _metaclass(type):
+ def mro(self):
+ return 1
+ class X(object, metaclass=_metaclass):
+ pass
except TypeError:
pass
else:
@@ -3575,11 +3574,11 @@
class E(D):
pass
- class F(D):
- __metaclass__ = WorkOnce
+ class F(D, metaclass=WorkOnce):
+ pass
- class G(D):
- __metaclass__ = WorkAlways
+ class G(D, metaclass=WorkAlways):
+ pass
# Immediate subclasses have their mro's adjusted in alphabetical
# order, so E's will get adjusted before adjusting F's fails. We
@@ -3690,15 +3689,15 @@
def dict_type_with_metaclass():
if verbose:
- print("Testing type of __dict__ when __metaclass__ set...")
+ print("Testing type of __dict__ when metaclass set...")
class B(object):
pass
class M(type):
pass
- class C:
+ class C(metaclass=M):
# In 2.3a1, C.__dict__ was a real dict rather than a dict proxy
- __metaclass__ = M
+ pass
veris(type(C.__dict__), type(B.__dict__))
def meth_class_get():