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Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
from test.test_support import verify, TestFailed, check_syntax, vereq
import warnings
warnings.filterwarnings("ignore", r"import \*", SyntaxWarning, "")
print "1. simple nesting"
def make_adder(x):
def adder(y):
return x + y
return adder
inc = make_adder(1)
plus10 = make_adder(10)
vereq(inc(1), 2)
vereq(plus10(-2), 8)
print "2. extra nesting"
def make_adder2(x):
def extra(): # check freevars passing through non-use scopes
def adder(y):
return x + y
return adder
return extra()
inc = make_adder2(1)
plus10 = make_adder2(10)
vereq(inc(1), 2)
vereq(plus10(-2), 8)
print "3. simple nesting + rebinding"
def make_adder3(x):
def adder(y):
return x + y
x = x + 1 # check tracking of assignment to x in defining scope
return adder
inc = make_adder3(0)
plus10 = make_adder3(9)
vereq(inc(1), 2)
vereq(plus10(-2), 8)
print "4. nesting with global but no free"
def make_adder4(): # XXX add exta level of indirection
def nest():
def nest():
def adder(y):
return global_x + y # check that plain old globals work
return adder
return nest()
return nest()
global_x = 1
adder = make_adder4()
vereq(adder(1), 2)
global_x = 10
vereq(adder(-2), 8)
print "5. nesting through class"
def make_adder5(x):
class Adder:
def __call__(self, y):
return x + y
return Adder()
inc = make_adder5(1)
plus10 = make_adder5(10)
vereq(inc(1), 2)
vereq(plus10(-2), 8)
print "6. nesting plus free ref to global"
def make_adder6(x):
global global_nest_x
def adder(y):
return global_nest_x + y
global_nest_x = x
return adder
inc = make_adder6(1)
plus10 = make_adder6(10)
vereq(inc(1), 11) # there's only one global
vereq(plus10(-2), 8)
print "7. nearest enclosing scope"
def f(x):
def g(y):
x = 42 # check that this masks binding in f()
def h(z):
return x + z
return h
return g(2)
test_func = f(10)
vereq(test_func(5), 47)
print "8. mixed freevars and cellvars"
def identity(x):
return x
def f(x, y, z):
def g(a, b, c):
a = a + x # 3
def h():
# z * (4 + 9)
# 3 * 13
return identity(z * (b + y))
y = c + z # 9
return h
return g
g = f(1, 2, 3)
h = g(2, 4, 6)
vereq(h(), 39)
print "9. free variable in method"
def test():
method_and_var = "var"
class Test:
def method_and_var(self):
return "method"
def test(self):
return method_and_var
def actual_global(self):
return str("global")
def str(self):
return str(self)
return Test()
t = test()
vereq(t.test(), "var")
vereq(t.method_and_var(), "method")
vereq(t.actual_global(), "global")
method_and_var = "var"
class Test:
# this class is not nested, so the rules are different
def method_and_var(self):
return "method"
def test(self):
return method_and_var
def actual_global(self):
return str("global")
def str(self):
return str(self)
t = Test()
vereq(t.test(), "var")
vereq(t.method_and_var(), "method")
vereq(t.actual_global(), "global")
print "10. recursion"
def f(x):
def fact(n):
if n == 0:
return 1
else:
return n * fact(n - 1)
if x >= 0:
return fact(x)
else:
raise ValueError, "x must be >= 0"
vereq(f(6), 720)
print "11. unoptimized namespaces"
check_syntax("""\
def unoptimized_clash1(strip):
def f(s):
from string import *
return strip(s) # ambiguity: free or local
return f
""")
check_syntax("""\
def unoptimized_clash2():
from string import *
def f(s):
return strip(s) # ambiguity: global or local
return f
""")
check_syntax("""\
def unoptimized_clash2():
from string import *
def g():
def f(s):
return strip(s) # ambiguity: global or local
return f
""")
# XXX could allow this for exec with const argument, but what's the point
check_syntax("""\
def error(y):
exec "a = 1"
def f(x):
return x + y
return f
""")
check_syntax("""\
def f(x):
def g():
return x
del x # can't del name
""")
check_syntax("""\
def f():
def g():
from string import *
return strip # global or local?
""")
# and verify a few cases that should work
exec """
def noproblem1():
from string import *
f = lambda x:x
def noproblem2():
from string import *
def f(x):
return x + 1
def noproblem3():
from string import *
def f(x):
global y
y = x
"""
print "12. lambdas"
f1 = lambda x: lambda y: x + y
inc = f1(1)
plus10 = f1(10)
vereq(inc(1), 2)
vereq(plus10(5), 15)
f2 = lambda x: (lambda : lambda y: x + y)()
inc = f2(1)
plus10 = f2(10)
vereq(inc(1), 2)
vereq(plus10(5), 15)
f3 = lambda x: lambda y: global_x + y
global_x = 1
inc = f3(None)
vereq(inc(2), 3)
f8 = lambda x, y, z: lambda a, b, c: lambda : z * (b + y)
g = f8(1, 2, 3)
h = g(2, 4, 6)
vereq(h(), 18)
print "13. UnboundLocal"
def errorInOuter():
print y
def inner():
return y
y = 1
def errorInInner():
def inner():
return y
inner()
y = 1
try:
errorInOuter()
except UnboundLocalError:
pass
else:
raise TestFailed
try:
errorInInner()
except NameError:
pass
else:
raise TestFailed
# test for bug #1501934: incorrect LOAD/STORE_GLOBAL generation
global_x = 1
def f():
global_x += 1
try:
f()
except UnboundLocalError:
pass
else:
raise TestFailed, 'scope of global_x not correctly determined'
print "14. complex definitions"
def makeReturner(*lst):
def returner():
return lst
return returner
vereq(makeReturner(1,2,3)(), (1,2,3))
def makeReturner2(**kwargs):
def returner():
return kwargs
return returner
vereq(makeReturner2(a=11)()['a'], 11)
def makeAddPair((a, b)):
def addPair((c, d)):
return (a + c, b + d)
return addPair
vereq(makeAddPair((1, 2))((100, 200)), (101,202))
print "15. scope of global statements"
# Examples posted by Samuele Pedroni to python-dev on 3/1/2001
# I
x = 7
def f():
x = 1
def g():
global x
def i():
def h():
return x
return h()
return i()
return g()
vereq(f(), 7)
vereq(x, 7)
# II
x = 7
def f():
x = 1
def g():
x = 2
def i():
def h():
return x
return h()
return i()
return g()
vereq(f(), 2)
vereq(x, 7)
# III
x = 7
def f():
x = 1
def g():
global x
x = 2
def i():
def h():
return x
return h()
return i()
return g()
vereq(f(), 2)
vereq(x, 2)
# IV
x = 7
def f():
x = 3
def g():
global x
x = 2
def i():
def h():
return x
return h()
return i()
return g()
vereq(f(), 2)
vereq(x, 2)
# XXX what about global statements in class blocks?
# do they affect methods?
x = 12
class Global:
global x
x = 13
def set(self, val):
x = val
def get(self):
return x
g = Global()
vereq(g.get(), 13)
g.set(15)
vereq(g.get(), 13)
print "16. check leaks"
class Foo:
count = 0
def __init__(self):
Foo.count += 1
def __del__(self):
Foo.count -= 1
def f1():
x = Foo()
def f2():
return x
f2()
for i in range(100):
f1()
vereq(Foo.count, 0)
print "17. class and global"
def test(x):
class Foo:
global x
def __call__(self, y):
return x + y
return Foo()
x = 0
vereq(test(6)(2), 8)
x = -1
vereq(test(3)(2), 5)
looked_up_by_load_name = False
class X:
# Implicit globals inside classes are be looked up by LOAD_NAME, not
# LOAD_GLOBAL.
locals()['looked_up_by_load_name'] = True
passed = looked_up_by_load_name
verify(X.passed)
print "18. verify that locals() works"
def f(x):
def g(y):
def h(z):
return y + z
w = x + y
y += 3
return locals()
return g
d = f(2)(4)
verify(d.has_key('h'))
del d['h']
vereq(d, {'x': 2, 'y': 7, 'w': 6})
print "19. var is bound and free in class"
def f(x):
class C:
def m(self):
return x
a = x
return C
inst = f(3)()
vereq(inst.a, inst.m())
print "20. interaction with trace function"
import sys
def tracer(a,b,c):
return tracer
def adaptgetter(name, klass, getter):
kind, des = getter
if kind == 1: # AV happens when stepping from this line to next
if des == "":
des = "_%s__%s" % (klass.__name__, name)
return lambda obj: getattr(obj, des)
class TestClass:
pass
sys.settrace(tracer)
adaptgetter("foo", TestClass, (1, ""))
sys.settrace(None)
try: sys.settrace()
except TypeError: pass
else: raise TestFailed, 'sys.settrace() did not raise TypeError'
print "20. eval and exec with free variables"
def f(x):
return lambda: x + 1
g = f(3)
try:
eval(g.func_code)
except TypeError:
pass
else:
print "eval() should have failed, because code contained free vars"
try:
exec g.func_code
except TypeError:
pass
else:
print "exec should have failed, because code contained free vars"
print "21. list comprehension with local variables"
try:
print bad
except NameError:
pass
else:
print "bad should not be defined"
def x():
[bad for s in 'a b' for bad in s.split()]
x()
try:
print bad
except NameError:
pass
print "22. eval with free variables"
def f(x):
def g():
x
eval("x + 1")
return g
f(4)()