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from test.test_support import verify, TestFailed
print "1. simple nesting"
def make_adder(x):
def adder(y):
return x + y
return adder
inc = make_adder(1)
plus10 = make_adder(10)
verify(inc(1) == 2)
verify(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)
verify(inc(1) == 2)
verify(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)
verify(inc(1) == 2)
verify(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()
verify(adder(1) == 2)
global_x = 10
verify(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)
verify(inc(1) == 2)
verify(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)
verify(inc(1) == 11) # there's only one global
verify(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)
verify(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)
verify(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()
verify(t.test() == "var")
verify(t.method_and_var() == "method")
verify(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()
verify(t.test() == "var")
verify(t.method_and_var() == "method")
verify(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"
verify(f(6) == 720)
print "11. unoptimized namespaces"
def check_syntax(s):
try:
compile(s, '?', 'exec')
except SyntaxError:
pass
else:
raise TestFailed
# XXX for now, it is easiest to call this a syntax error:
# explicit is better than implicit...
test1 = \
"""def unoptimized_clash1(strip):
def f(s):
from string import *
return strip(s) # ambiguity: free or local
return f
"""
check_syntax(test1)
# a little harder to reject this one, but possible...
test2 = \
"""def unoptimized_clash2():
from string import *
def f(s):
return strip(s) # ambiguity: global or local
return f
"""
# check_syntax(test2)
# XXX could allow this for exec with const argument, but what's the point
test3 = \
"""def error(y):
exec "a = 1"
def f(x):
return x + y
return f
"""
check_syntax(test3)
test4 = \
"""def f(x):
def g():
return x
del x
"""
check_syntax(test4)
print "12. lambdas"
f1 = lambda x: lambda y: x + y
inc = f1(1)
plus10 = f1(10)
verify(inc(1) == 2)
verify(plus10(5) == 15)
f2 = lambda x: (lambda : lambda y: x + y)()
inc = f2(1)
plus10 = f2(10)
verify(inc(1) == 2)
verify(plus10(5) == 15)
f3 = lambda x: lambda y: global_x + y
global_x = 1
inc = f3(None)
verify(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)
verify(h() == 18)
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