mirror of
https://github.com/python/cpython.git
synced 2024-11-25 10:54:51 +08:00
310 lines
9.6 KiB
Python
310 lines
9.6 KiB
Python
import unittest
|
|
from test import support
|
|
|
|
def funcattrs(**kwds):
|
|
def decorate(func):
|
|
func.__dict__.update(kwds)
|
|
return func
|
|
return decorate
|
|
|
|
class MiscDecorators (object):
|
|
@staticmethod
|
|
def author(name):
|
|
def decorate(func):
|
|
func.__dict__['author'] = name
|
|
return func
|
|
return decorate
|
|
|
|
# -----------------------------------------------
|
|
|
|
class DbcheckError (Exception):
|
|
def __init__(self, exprstr, func, args, kwds):
|
|
# A real version of this would set attributes here
|
|
Exception.__init__(self, "dbcheck %r failed (func=%s args=%s kwds=%s)" %
|
|
(exprstr, func, args, kwds))
|
|
|
|
|
|
def dbcheck(exprstr, globals=None, locals=None):
|
|
"Decorator to implement debugging assertions"
|
|
def decorate(func):
|
|
expr = compile(exprstr, "dbcheck-%s" % func.__name__, "eval")
|
|
def check(*args, **kwds):
|
|
if not eval(expr, globals, locals):
|
|
raise DbcheckError(exprstr, func, args, kwds)
|
|
return func(*args, **kwds)
|
|
return check
|
|
return decorate
|
|
|
|
# -----------------------------------------------
|
|
|
|
def countcalls(counts):
|
|
"Decorator to count calls to a function"
|
|
def decorate(func):
|
|
func_name = func.__name__
|
|
counts[func_name] = 0
|
|
def call(*args, **kwds):
|
|
counts[func_name] += 1
|
|
return func(*args, **kwds)
|
|
call.__name__ = func_name
|
|
return call
|
|
return decorate
|
|
|
|
# -----------------------------------------------
|
|
|
|
def memoize(func):
|
|
saved = {}
|
|
def call(*args):
|
|
try:
|
|
return saved[args]
|
|
except KeyError:
|
|
res = func(*args)
|
|
saved[args] = res
|
|
return res
|
|
except TypeError:
|
|
# Unhashable argument
|
|
return func(*args)
|
|
call.__name__ = func.__name__
|
|
return call
|
|
|
|
# -----------------------------------------------
|
|
|
|
class TestDecorators(unittest.TestCase):
|
|
|
|
def test_single(self):
|
|
class C(object):
|
|
@staticmethod
|
|
def foo(): return 42
|
|
self.assertEqual(C.foo(), 42)
|
|
self.assertEqual(C().foo(), 42)
|
|
|
|
def test_staticmethod_function(self):
|
|
@staticmethod
|
|
def notamethod(x):
|
|
return x
|
|
self.assertRaises(TypeError, notamethod, 1)
|
|
|
|
def test_dotted(self):
|
|
decorators = MiscDecorators()
|
|
@decorators.author('Cleese')
|
|
def foo(): return 42
|
|
self.assertEqual(foo(), 42)
|
|
self.assertEqual(foo.author, 'Cleese')
|
|
|
|
def test_argforms(self):
|
|
# A few tests of argument passing, as we use restricted form
|
|
# of expressions for decorators.
|
|
|
|
def noteargs(*args, **kwds):
|
|
def decorate(func):
|
|
setattr(func, 'dbval', (args, kwds))
|
|
return func
|
|
return decorate
|
|
|
|
args = ( 'Now', 'is', 'the', 'time' )
|
|
kwds = dict(one=1, two=2)
|
|
@noteargs(*args, **kwds)
|
|
def f1(): return 42
|
|
self.assertEqual(f1(), 42)
|
|
self.assertEqual(f1.dbval, (args, kwds))
|
|
|
|
@noteargs('terry', 'gilliam', eric='idle', john='cleese')
|
|
def f2(): return 84
|
|
self.assertEqual(f2(), 84)
|
|
self.assertEqual(f2.dbval, (('terry', 'gilliam'),
|
|
dict(eric='idle', john='cleese')))
|
|
|
|
@noteargs(1, 2,)
|
|
def f3(): pass
|
|
self.assertEqual(f3.dbval, ((1, 2), {}))
|
|
|
|
def test_dbcheck(self):
|
|
@dbcheck('args[1] is not None')
|
|
def f(a, b):
|
|
return a + b
|
|
self.assertEqual(f(1, 2), 3)
|
|
self.assertRaises(DbcheckError, f, 1, None)
|
|
|
|
def test_memoize(self):
|
|
counts = {}
|
|
|
|
@memoize
|
|
@countcalls(counts)
|
|
def double(x):
|
|
return x * 2
|
|
self.assertEqual(double.__name__, 'double')
|
|
|
|
self.assertEqual(counts, dict(double=0))
|
|
|
|
# Only the first call with a given argument bumps the call count:
|
|
#
|
|
self.assertEqual(double(2), 4)
|
|
self.assertEqual(counts['double'], 1)
|
|
self.assertEqual(double(2), 4)
|
|
self.assertEqual(counts['double'], 1)
|
|
self.assertEqual(double(3), 6)
|
|
self.assertEqual(counts['double'], 2)
|
|
|
|
# Unhashable arguments do not get memoized:
|
|
#
|
|
self.assertEqual(double([10]), [10, 10])
|
|
self.assertEqual(counts['double'], 3)
|
|
self.assertEqual(double([10]), [10, 10])
|
|
self.assertEqual(counts['double'], 4)
|
|
|
|
def test_errors(self):
|
|
# Test syntax restrictions - these are all compile-time errors:
|
|
#
|
|
for expr in [ "1+2", "x[3]", "(1, 2)" ]:
|
|
# Sanity check: is expr is a valid expression by itself?
|
|
compile(expr, "testexpr", "exec")
|
|
|
|
codestr = "@%s\ndef f(): pass" % expr
|
|
self.assertRaises(SyntaxError, compile, codestr, "test", "exec")
|
|
|
|
# You can't put multiple decorators on a single line:
|
|
#
|
|
self.assertRaises(SyntaxError, compile,
|
|
"@f1 @f2\ndef f(): pass", "test", "exec")
|
|
|
|
# Test runtime errors
|
|
|
|
def unimp(func):
|
|
raise NotImplementedError
|
|
context = dict(nullval=None, unimp=unimp)
|
|
|
|
for expr, exc in [ ("undef", NameError),
|
|
("nullval", TypeError),
|
|
("nullval.attr", AttributeError),
|
|
("unimp", NotImplementedError)]:
|
|
codestr = "@%s\ndef f(): pass\nassert f() is None" % expr
|
|
code = compile(codestr, "test", "exec")
|
|
self.assertRaises(exc, eval, code, context)
|
|
|
|
def test_double(self):
|
|
class C(object):
|
|
@funcattrs(abc=1, xyz="haha")
|
|
@funcattrs(booh=42)
|
|
def foo(self): return 42
|
|
self.assertEqual(C().foo(), 42)
|
|
self.assertEqual(C.foo.abc, 1)
|
|
self.assertEqual(C.foo.xyz, "haha")
|
|
self.assertEqual(C.foo.booh, 42)
|
|
|
|
def test_order(self):
|
|
# Test that decorators are applied in the proper order to the function
|
|
# they are decorating.
|
|
def callnum(num):
|
|
"""Decorator factory that returns a decorator that replaces the
|
|
passed-in function with one that returns the value of 'num'"""
|
|
def deco(func):
|
|
return lambda: num
|
|
return deco
|
|
@callnum(2)
|
|
@callnum(1)
|
|
def foo(): return 42
|
|
self.assertEqual(foo(), 2,
|
|
"Application order of decorators is incorrect")
|
|
|
|
def test_eval_order(self):
|
|
# Evaluating a decorated function involves four steps for each
|
|
# decorator-maker (the function that returns a decorator):
|
|
#
|
|
# 1: Evaluate the decorator-maker name
|
|
# 2: Evaluate the decorator-maker arguments (if any)
|
|
# 3: Call the decorator-maker to make a decorator
|
|
# 4: Call the decorator
|
|
#
|
|
# When there are multiple decorators, these steps should be
|
|
# performed in the above order for each decorator, but we should
|
|
# iterate through the decorators in the reverse of the order they
|
|
# appear in the source.
|
|
|
|
actions = []
|
|
|
|
def make_decorator(tag):
|
|
actions.append('makedec' + tag)
|
|
def decorate(func):
|
|
actions.append('calldec' + tag)
|
|
return func
|
|
return decorate
|
|
|
|
class NameLookupTracer (object):
|
|
def __init__(self, index):
|
|
self.index = index
|
|
|
|
def __getattr__(self, fname):
|
|
if fname == 'make_decorator':
|
|
opname, res = ('evalname', make_decorator)
|
|
elif fname == 'arg':
|
|
opname, res = ('evalargs', str(self.index))
|
|
else:
|
|
assert False, "Unknown attrname %s" % fname
|
|
actions.append('%s%d' % (opname, self.index))
|
|
return res
|
|
|
|
c1, c2, c3 = map(NameLookupTracer, [ 1, 2, 3 ])
|
|
|
|
expected_actions = [ 'evalname1', 'evalargs1', 'makedec1',
|
|
'evalname2', 'evalargs2', 'makedec2',
|
|
'evalname3', 'evalargs3', 'makedec3',
|
|
'calldec3', 'calldec2', 'calldec1' ]
|
|
|
|
actions = []
|
|
@c1.make_decorator(c1.arg)
|
|
@c2.make_decorator(c2.arg)
|
|
@c3.make_decorator(c3.arg)
|
|
def foo(): return 42
|
|
self.assertEqual(foo(), 42)
|
|
|
|
self.assertEqual(actions, expected_actions)
|
|
|
|
# Test the equivalence claim in chapter 7 of the reference manual.
|
|
#
|
|
actions = []
|
|
def bar(): return 42
|
|
bar = c1.make_decorator(c1.arg)(c2.make_decorator(c2.arg)(c3.make_decorator(c3.arg)(bar)))
|
|
self.assertEqual(bar(), 42)
|
|
self.assertEqual(actions, expected_actions)
|
|
|
|
class TestClassDecorators(unittest.TestCase):
|
|
|
|
def test_simple(self):
|
|
def plain(x):
|
|
x.extra = 'Hello'
|
|
return x
|
|
@plain
|
|
class C(object): pass
|
|
self.assertEqual(C.extra, 'Hello')
|
|
|
|
def test_double(self):
|
|
def ten(x):
|
|
x.extra = 10
|
|
return x
|
|
def add_five(x):
|
|
x.extra += 5
|
|
return x
|
|
|
|
@add_five
|
|
@ten
|
|
class C(object): pass
|
|
self.assertEqual(C.extra, 15)
|
|
|
|
def test_order(self):
|
|
def applied_first(x):
|
|
x.extra = 'first'
|
|
return x
|
|
def applied_second(x):
|
|
x.extra = 'second'
|
|
return x
|
|
@applied_second
|
|
@applied_first
|
|
class C(object): pass
|
|
self.assertEqual(C.extra, 'second')
|
|
|
|
def test_main():
|
|
support.run_unittest(TestDecorators)
|
|
support.run_unittest(TestClassDecorators)
|
|
|
|
if __name__=="__main__":
|
|
test_main()
|