from test_support import verify, TestFailed, check_syntax 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) 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" 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) 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) 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 print "14. complex definitions" def makeReturner(*lst): def returner(): return lst return returner verify(makeReturner(1,2,3)() == (1,2,3)) def makeReturner2(**kwargs): def returner(): return kwargs return returner verify(makeReturner2(a=11)()['a'] == 11) def makeAddPair((a, b)): def addPair((c, d)): return (a + c, b + d) return addPair verify(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() verify(f() == 7) verify(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() verify(f() == 2) verify(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() verify(f() == 2) verify(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() verify(f() == 2) verify(x == 2) 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() import os if os.name == 'java': from java.lang import System, Thread System.gc() Thread.sleep(100) System.gc() verify(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 verify(test(6)(2) == 8) x = -1 verify(test(3)(2) == 5) 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'] verify(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)() verify(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)()