mirror of
https://github.com/python/cpython.git
synced 2025-07-29 22:24:49 +00:00
88f1c04215
Re http://bugs.python.org/issue4315 The symbol table used the same name dictionaries to recursively analyze each of its child blocks, even though the dictionaries are modified during analysis. The fix is to create new temporary dictionaries via the analyze_child_block(). The only information that needs to propagate back up is the names of the free variables. Add more comments and break out a helper function. This code doesn't get any easier to understand when you only look at it once a year.
665 lines
15 KiB
Python
665 lines
15 KiB
Python
import unittest
|
|
from test.test_support import check_syntax_error, run_unittest
|
|
|
|
import warnings
|
|
warnings.filterwarnings("ignore", r"import \*", SyntaxWarning, "<test string>")
|
|
warnings.filterwarnings("ignore", r"import \*", SyntaxWarning, "<string>")
|
|
|
|
class ScopeTests(unittest.TestCase):
|
|
|
|
def testSimpleNesting(self):
|
|
|
|
def make_adder(x):
|
|
def adder(y):
|
|
return x + y
|
|
return adder
|
|
|
|
inc = make_adder(1)
|
|
plus10 = make_adder(10)
|
|
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(-2), 8)
|
|
|
|
def testExtraNesting(self):
|
|
|
|
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)
|
|
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(-2), 8)
|
|
|
|
def testSimpleAndRebinding(self):
|
|
|
|
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)
|
|
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(-2), 8)
|
|
|
|
def testNestingGlobalNoFree(self):
|
|
|
|
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()
|
|
self.assertEqual(adder(1), 2)
|
|
|
|
global_x = 10
|
|
self.assertEqual(adder(-2), 8)
|
|
|
|
def testNestingThroughClass(self):
|
|
|
|
def make_adder5(x):
|
|
class Adder:
|
|
def __call__(self, y):
|
|
return x + y
|
|
return Adder()
|
|
|
|
inc = make_adder5(1)
|
|
plus10 = make_adder5(10)
|
|
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(-2), 8)
|
|
|
|
def testNestingPlusFreeRefToGlobal(self):
|
|
|
|
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)
|
|
|
|
self.assertEqual(inc(1), 11) # there's only one global
|
|
self.assertEqual(plus10(-2), 8)
|
|
|
|
def testNearestEnclosingScope(self):
|
|
|
|
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)
|
|
self.assertEqual(test_func(5), 47)
|
|
|
|
def testMixedFreevarsAndCellvars(self):
|
|
|
|
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)
|
|
self.assertEqual(h(), 39)
|
|
|
|
def testFreeVarInMethod(self):
|
|
|
|
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()
|
|
self.assertEqual(t.test(), "var")
|
|
self.assertEqual(t.method_and_var(), "method")
|
|
self.assertEqual(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()
|
|
self.assertEqual(t.test(), "var")
|
|
self.assertEqual(t.method_and_var(), "method")
|
|
self.assertEqual(t.actual_global(), "global")
|
|
|
|
def testRecursion(self):
|
|
|
|
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"
|
|
|
|
self.assertEqual(f(6), 720)
|
|
|
|
|
|
def testUnoptimizedNamespaces(self):
|
|
|
|
check_syntax_error(self, """\
|
|
def unoptimized_clash1(strip):
|
|
def f(s):
|
|
from string import *
|
|
return strip(s) # ambiguity: free or local
|
|
return f
|
|
""")
|
|
|
|
check_syntax_error(self, """\
|
|
def unoptimized_clash2():
|
|
from string import *
|
|
def f(s):
|
|
return strip(s) # ambiguity: global or local
|
|
return f
|
|
""")
|
|
|
|
check_syntax_error(self, """\
|
|
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_error(self, """\
|
|
def error(y):
|
|
exec "a = 1"
|
|
def f(x):
|
|
return x + y
|
|
return f
|
|
""")
|
|
|
|
check_syntax_error(self, """\
|
|
def f(x):
|
|
def g():
|
|
return x
|
|
del x # can't del name
|
|
""")
|
|
|
|
check_syntax_error(self, """\
|
|
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
|
|
"""
|
|
|
|
def testLambdas(self):
|
|
|
|
f1 = lambda x: lambda y: x + y
|
|
inc = f1(1)
|
|
plus10 = f1(10)
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(5), 15)
|
|
|
|
f2 = lambda x: (lambda : lambda y: x + y)()
|
|
inc = f2(1)
|
|
plus10 = f2(10)
|
|
self.assertEqual(inc(1), 2)
|
|
self.assertEqual(plus10(5), 15)
|
|
|
|
f3 = lambda x: lambda y: global_x + y
|
|
global_x = 1
|
|
inc = f3(None)
|
|
self.assertEqual(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)
|
|
self.assertEqual(h(), 18)
|
|
|
|
def testUnboundLocal(self):
|
|
|
|
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:
|
|
self.fail()
|
|
|
|
try:
|
|
errorInInner()
|
|
except NameError:
|
|
pass
|
|
else:
|
|
self.fail()
|
|
|
|
# test for bug #1501934: incorrect LOAD/STORE_GLOBAL generation
|
|
exec """
|
|
global_x = 1
|
|
def f():
|
|
global_x += 1
|
|
try:
|
|
f()
|
|
except UnboundLocalError:
|
|
pass
|
|
else:
|
|
fail('scope of global_x not correctly determined')
|
|
""" in {'fail': self.fail}
|
|
|
|
def testComplexDefinitions(self):
|
|
|
|
def makeReturner(*lst):
|
|
def returner():
|
|
return lst
|
|
return returner
|
|
|
|
self.assertEqual(makeReturner(1,2,3)(), (1,2,3))
|
|
|
|
def makeReturner2(**kwargs):
|
|
def returner():
|
|
return kwargs
|
|
return returner
|
|
|
|
self.assertEqual(makeReturner2(a=11)()['a'], 11)
|
|
|
|
def makeAddPair((a, b)):
|
|
def addPair((c, d)):
|
|
return (a + c, b + d)
|
|
return addPair
|
|
|
|
self.assertEqual(makeAddPair((1, 2))((100, 200)), (101,202))
|
|
|
|
def testScopeOfGlobalStmt(self):
|
|
# Examples posted by Samuele Pedroni to python-dev on 3/1/2001
|
|
|
|
exec """\
|
|
# I
|
|
x = 7
|
|
def f():
|
|
x = 1
|
|
def g():
|
|
global x
|
|
def i():
|
|
def h():
|
|
return x
|
|
return h()
|
|
return i()
|
|
return g()
|
|
self.assertEqual(f(), 7)
|
|
self.assertEqual(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()
|
|
self.assertEqual(f(), 2)
|
|
self.assertEqual(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()
|
|
self.assertEqual(f(), 2)
|
|
self.assertEqual(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()
|
|
self.assertEqual(f(), 2)
|
|
self.assertEqual(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()
|
|
self.assertEqual(g.get(), 13)
|
|
g.set(15)
|
|
self.assertEqual(g.get(), 13)
|
|
"""
|
|
|
|
def testLeaks(self):
|
|
|
|
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()
|
|
|
|
self.assertEqual(Foo.count, 0)
|
|
|
|
def testClassAndGlobal(self):
|
|
|
|
exec """\
|
|
def test(x):
|
|
class Foo:
|
|
global x
|
|
def __call__(self, y):
|
|
return x + y
|
|
return Foo()
|
|
|
|
x = 0
|
|
self.assertEqual(test(6)(2), 8)
|
|
x = -1
|
|
self.assertEqual(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
|
|
|
|
self.assert_(X.passed)
|
|
"""
|
|
|
|
def testLocalsFunction(self):
|
|
|
|
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)
|
|
self.assert_(d.has_key('h'))
|
|
del d['h']
|
|
self.assertEqual(d, {'x': 2, 'y': 7, 'w': 6})
|
|
|
|
def testLocalsClass(self):
|
|
# This test verifies that calling locals() does not pollute
|
|
# the local namespace of the class with free variables. Old
|
|
# versions of Python had a bug, where a free variable being
|
|
# passed through a class namespace would be inserted into
|
|
# locals() by locals() or exec or a trace function.
|
|
#
|
|
# The real bug lies in frame code that copies variables
|
|
# between fast locals and the locals dict, e.g. when executing
|
|
# a trace function.
|
|
|
|
def f(x):
|
|
class C:
|
|
x = 12
|
|
def m(self):
|
|
return x
|
|
locals()
|
|
return C
|
|
|
|
self.assertEqual(f(1).x, 12)
|
|
|
|
def f(x):
|
|
class C:
|
|
y = x
|
|
def m(self):
|
|
return x
|
|
z = list(locals())
|
|
return C
|
|
|
|
varnames = f(1).z
|
|
self.assert_("x" not in varnames)
|
|
self.assert_("y" in varnames)
|
|
|
|
def testLocalsClass_WithTrace(self):
|
|
# Issue23728: after the trace function returns, the locals()
|
|
# dictionary is used to update all variables, this used to
|
|
# include free variables. But in class statements, free
|
|
# variables are not inserted...
|
|
import sys
|
|
sys.settrace(lambda a,b,c:None)
|
|
try:
|
|
x = 12
|
|
|
|
class C:
|
|
def f(self):
|
|
return x
|
|
|
|
self.assertEquals(x, 12) # Used to raise UnboundLocalError
|
|
finally:
|
|
sys.settrace(None)
|
|
|
|
def testBoundAndFree(self):
|
|
# var is bound and free in class
|
|
|
|
def f(x):
|
|
class C:
|
|
def m(self):
|
|
return x
|
|
a = x
|
|
return C
|
|
|
|
inst = f(3)()
|
|
self.assertEqual(inst.a, inst.m())
|
|
|
|
def testInteractionWithTraceFunc(self):
|
|
|
|
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)
|
|
|
|
self.assertRaises(TypeError, sys.settrace)
|
|
|
|
def testEvalExecFreeVars(self):
|
|
|
|
def f(x):
|
|
return lambda: x + 1
|
|
|
|
g = f(3)
|
|
self.assertRaises(TypeError, eval, g.func_code)
|
|
|
|
try:
|
|
exec g.func_code in {}
|
|
except TypeError:
|
|
pass
|
|
else:
|
|
self.fail("exec should have failed, because code contained free vars")
|
|
|
|
def testListCompLocalVars(self):
|
|
|
|
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
|
|
|
|
def testEvalFreeVars(self):
|
|
|
|
def f(x):
|
|
def g():
|
|
x
|
|
eval("x + 1")
|
|
return g
|
|
|
|
f(4)()
|
|
|
|
def testFreeingCell(self):
|
|
# Test what happens when a finalizer accesses
|
|
# the cell where the object was stored.
|
|
class Special:
|
|
def __del__(self):
|
|
nestedcell_get()
|
|
|
|
def f():
|
|
global nestedcell_get
|
|
def nestedcell_get():
|
|
return c
|
|
|
|
c = (Special(),)
|
|
c = 2
|
|
|
|
f() # used to crash the interpreter...
|
|
|
|
def testGlobalInParallelNestedFunctions(self):
|
|
# A symbol table bug leaked the global statement from one
|
|
# function to other nested functions in the same block.
|
|
# This test verifies that a global statement in the first
|
|
# function does not affect the second function.
|
|
CODE = """def f():
|
|
y = 1
|
|
def g():
|
|
global y
|
|
return y
|
|
def h():
|
|
return y + 1
|
|
return g, h
|
|
|
|
y = 9
|
|
g, h = f()
|
|
result9 = g()
|
|
result2 = h()
|
|
"""
|
|
local_ns = {}
|
|
global_ns = {}
|
|
exec CODE in local_ns, global_ns
|
|
self.assertEqual(2, global_ns["result2"])
|
|
self.assertEqual(9, global_ns["result9"])
|
|
|
|
|
|
def test_main():
|
|
run_unittest(ScopeTests)
|
|
|
|
if __name__ == '__main__':
|
|
test_main()
|