bugtests.test381.py Maven / Gradle / Ivy
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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.
"""
namespace (PyStringMap) deletion-confused insert bug
"""
#==============================================
# we need some stuff to find a pair of keys
# with the same initial index in hash table
import support
from java.lang.System import identityHashCode
from java.lang import String
def hashCode(key):
return identityHashCode(String.intern(key))
def scanKeys(base, r, sz, deep):
for i in xrange(65,91): #chars 'A'-'Z'
key = base+chr(i)
#sz is hash table size
if hashCode(key)%sz == r:
break
if deep:
key = scanKeys(base, r, sz, deep-1)
if key is not None:
break
return key
# find a key with the same hash index as key1
def findPairKey(key1, sz=7):
#in empty PyStringMap hash table has size 7
r=hashCode(key1)%sz
base=""
for deep in xrange(0,15):
key = scanKeys(base, r, sz, deep)
if key is not None: return key
class AA: pass
d = AA().__dict__
# now d is an empty PyStringMap dict
key1="key1"
#find a pair key for key1
key2 = findPairKey(key1)
# key2 consists of upper case characters (by construction)
# and always differs from key1
#print "key1=",repr(key1)," key2=",repr(key2)
d[key2] = "foo" #key2 occupies initial slot
d[key1] = "value1" #key1 occupies next slot
del d[key2] #initial slot is marked by ""
d[key1] = "value2" #key1 replaces "" in the first
#slot but not old key1 value!
del d[key1]
#we hope key1 is not in the dict any more...
try:
v=d[key1]
#print "Oops! d[key1]=",repr(v) #Oops! Magically ressurected!
raise support.TestError,"namespace deletion-confused insert bug"
except KeyError:
#print "OK"
pass