lib-python.2.5.test.test_scope.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
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)()