Get rid of the superstitious "~" in dict hashing's "i = (~hash) & mask".
The comment following used to say:
/* We use ~hash instead of hash, as degenerate hash functions, such
as for ints <sigh>, can have lots of leading zeros. It's not
really a performance risk, but better safe than sorry.
12-Dec-00 tim: so ~hash produces lots of leading ones instead --
what's the gain? */
That is, there was never a good reason for doing it. And to the contrary,
as explained on Python-Dev last December, it tended to make the *sum*
(i + incr) & mask (which is the first table index examined in case of
collison) the same "too often" across distinct hashes.
Changing to the simpler "i = hash & mask" reduced the number of string-dict
collisions (== # number of times we go around the lookup for-loop) from about
6 million to 5 million during a full run of the test suite (these are
approximate because the test suite does some random stuff from run to run).
The number of collisions in non-string dicts also decreased, but not as
dramatically.
Note that this may, for a given dict, change the order (wrt previous
releases) of entries exposed by .keys(), .values() and .items(). A number
of std tests suffered bogus failures as a result. For dicts keyed by
small ints, or (less so) by characters, the order is much more likely to be
in increasing order of key now; e.g.,
>>> d = {}
>>> for i in range(10):
... d[i] = i
...
>>> d
{0: 0, 1: 1, 2: 2, 3: 3, 4: 4, 5: 5, 6: 6, 7: 7, 8: 8, 9: 9}
>>>
Unfortunately. people may latch on to that in small examples and draw a
bogus conclusion.
test_support.py
Moved test_extcall's sortdict() into test_support, made it stronger,
and imported sortdict into other std tests that needed it.
test_unicode.py
Excluced cp875 from the "roundtrip over range(128)" test, because
cp875 doesn't have a well-defined inverse for unicode("?", "cp875").
See Python-Dev for excruciating details.
Cookie.py
Chaged various output functions to sort dicts before building
strings from them.
test_extcall
Fiddled the expected-result file. This remains sensitive to native
dict ordering, because, e.g., if there are multiple errors in a
keyword-arg dict (and test_extcall sets up many cases like that), the
specific error Python complains about first depends on native dict
ordering.
diff --git a/Lib/test/output/test_cookie b/Lib/test/output/test_cookie
index 64b9d04..221c72a 100644
--- a/Lib/test/output/test_cookie
+++ b/Lib/test/output/test_cookie
@@ -1,11 +1,11 @@
test_cookie
-<SimpleCookie: vienna='finger' chips='ahoy'>
-Set-Cookie: vienna=finger;
+<SimpleCookie: chips='ahoy' vienna='finger'>
Set-Cookie: chips=ahoy;
- vienna 'finger' 'finger'
Set-Cookie: vienna=finger;
chips 'ahoy' 'ahoy'
Set-Cookie: chips=ahoy;
+ vienna 'finger' 'finger'
+Set-Cookie: vienna=finger;
<SimpleCookie: keebler='E=mc2; L="Loves"; fudge=\n;'>
Set-Cookie: keebler="E=mc2; L=\"Loves\"; fudge=\012;";
keebler 'E=mc2; L="Loves"; fudge=\n;' 'E=mc2; L="Loves"; fudge=\n;'
diff --git a/Lib/test/output/test_extcall b/Lib/test/output/test_extcall
index 58f52d4..24e8c8c 100644
--- a/Lib/test/output/test_extcall
+++ b/Lib/test/output/test_extcall
@@ -40,7 +40,7 @@
za () {'a': 'aa'} -> ok za aa B D E V a
za () {'d': 'dd'} -> za() got an unexpected keyword argument 'd'
za () {'a': 'aa', 'd': 'dd'} -> za() got an unexpected keyword argument 'd'
-za () {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> za() got an unexpected keyword argument 'd'
+za () {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> za() got an unexpected keyword argument 'b'
za (1, 2) {} -> za() takes exactly 1 argument (2 given)
za (1, 2) {'a': 'aa'} -> za() takes exactly 1 non-keyword argument (2 given)
za (1, 2) {'d': 'dd'} -> za() takes exactly 1 non-keyword argument (2 given)
@@ -59,8 +59,8 @@
zade (1, 2) {} -> ok zade 1 B 2 e V e
zade (1, 2) {'a': 'aa'} -> zade() got multiple values for keyword argument 'a'
zade (1, 2) {'d': 'dd'} -> zade() got multiple values for keyword argument 'd'
-zade (1, 2) {'a': 'aa', 'd': 'dd'} -> zade() got multiple values for keyword argument 'd'
-zade (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zade() got multiple values for keyword argument 'd'
+zade (1, 2) {'a': 'aa', 'd': 'dd'} -> zade() got multiple values for keyword argument 'a'
+zade (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zade() got multiple values for keyword argument 'a'
zade (1, 2, 3, 4, 5) {} -> zade() takes at most 3 arguments (5 given)
zade (1, 2, 3, 4, 5) {'a': 'aa'} -> zade() takes at most 3 non-keyword arguments (5 given)
zade (1, 2, 3, 4, 5) {'d': 'dd'} -> zade() takes at most 3 non-keyword arguments (5 given)
@@ -75,7 +75,7 @@
zabk (1, 2) {'a': 'aa'} -> zabk() got multiple values for keyword argument 'a'
zabk (1, 2) {'d': 'dd'} -> ok zabk 1 2 D E V {'d': 'dd'}
zabk (1, 2) {'a': 'aa', 'd': 'dd'} -> zabk() got multiple values for keyword argument 'a'
-zabk (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabk() got multiple values for keyword argument 'b'
+zabk (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabk() got multiple values for keyword argument 'a'
zabk (1, 2, 3, 4, 5) {} -> zabk() takes exactly 2 arguments (5 given)
zabk (1, 2, 3, 4, 5) {'a': 'aa'} -> zabk() takes exactly 2 non-keyword arguments (5 given)
zabk (1, 2, 3, 4, 5) {'d': 'dd'} -> zabk() takes exactly 2 non-keyword arguments (5 given)
@@ -90,12 +90,12 @@
zabdv (1, 2) {'a': 'aa'} -> zabdv() got multiple values for keyword argument 'a'
zabdv (1, 2) {'d': 'dd'} -> ok zabdv 1 2 dd E () d
zabdv (1, 2) {'a': 'aa', 'd': 'dd'} -> zabdv() got multiple values for keyword argument 'a'
-zabdv (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdv() got an unexpected keyword argument 'e'
+zabdv (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdv() got multiple values for keyword argument 'a'
zabdv (1, 2, 3, 4, 5) {} -> ok zabdv 1 2 3 E (4, 5) e
zabdv (1, 2, 3, 4, 5) {'a': 'aa'} -> zabdv() got multiple values for keyword argument 'a'
zabdv (1, 2, 3, 4, 5) {'d': 'dd'} -> zabdv() got multiple values for keyword argument 'd'
-zabdv (1, 2, 3, 4, 5) {'a': 'aa', 'd': 'dd'} -> zabdv() got multiple values for keyword argument 'd'
-zabdv (1, 2, 3, 4, 5) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdv() got multiple values for keyword argument 'd'
+zabdv (1, 2, 3, 4, 5) {'a': 'aa', 'd': 'dd'} -> zabdv() got multiple values for keyword argument 'a'
+zabdv (1, 2, 3, 4, 5) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdv() got multiple values for keyword argument 'a'
zabdevk () {} -> zabdevk() takes at least 2 arguments (0 given)
zabdevk () {'a': 'aa'} -> zabdevk() takes at least 2 non-keyword arguments (1 given)
zabdevk () {'d': 'dd'} -> zabdevk() takes at least 2 non-keyword arguments (0 given)
@@ -105,9 +105,9 @@
zabdevk (1, 2) {'a': 'aa'} -> zabdevk() got multiple values for keyword argument 'a'
zabdevk (1, 2) {'d': 'dd'} -> ok zabdevk 1 2 dd e () {}
zabdevk (1, 2) {'a': 'aa', 'd': 'dd'} -> zabdevk() got multiple values for keyword argument 'a'
-zabdevk (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdevk() got multiple values for keyword argument 'b'
+zabdevk (1, 2) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdevk() got multiple values for keyword argument 'a'
zabdevk (1, 2, 3, 4, 5) {} -> ok zabdevk 1 2 3 4 (5,) {}
zabdevk (1, 2, 3, 4, 5) {'a': 'aa'} -> zabdevk() got multiple values for keyword argument 'a'
zabdevk (1, 2, 3, 4, 5) {'d': 'dd'} -> zabdevk() got multiple values for keyword argument 'd'
-zabdevk (1, 2, 3, 4, 5) {'a': 'aa', 'd': 'dd'} -> zabdevk() got multiple values for keyword argument 'd'
-zabdevk (1, 2, 3, 4, 5) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdevk() got multiple values for keyword argument 'd'
+zabdevk (1, 2, 3, 4, 5) {'a': 'aa', 'd': 'dd'} -> zabdevk() got multiple values for keyword argument 'a'
+zabdevk (1, 2, 3, 4, 5) {'a': 'aa', 'b': 'bb', 'd': 'dd', 'e': 'ee'} -> zabdevk() got multiple values for keyword argument 'a'
diff --git a/Lib/test/test_cookie.py b/Lib/test/test_cookie.py
index 2063dbf..40c881f 100644
--- a/Lib/test/test_cookie.py
+++ b/Lib/test/test_cookie.py
@@ -20,7 +20,9 @@
C = Cookie.SimpleCookie() ; C.load(data)
print repr(C)
print str(C)
- for k, v in dict.items():
+ items = dict.items()
+ items.sort()
+ for k, v in items:
print ' ', k, repr( C[k].value ), repr(v)
verify(C[k].value == v)
print C[k]
diff --git a/Lib/test/test_extcall.py b/Lib/test/test_extcall.py
index 274e943..9effac7 100644
--- a/Lib/test/test_extcall.py
+++ b/Lib/test/test_extcall.py
@@ -1,14 +1,6 @@
-from test_support import verify, verbose, TestFailed
+from test_support import verify, verbose, TestFailed, sortdict
from UserList import UserList
-def sortdict(d):
- keys = d.keys()
- keys.sort()
- lst = []
- for k in keys:
- lst.append("%r: %r" % (k, d[k]))
- return "{%s}" % ", ".join(lst)
-
def f(*a, **k):
print a, sortdict(k)
@@ -228,8 +220,9 @@
lambda x: '%s="%s"' % (x, x), defargs)
if vararg: arglist.append('*' + vararg)
if kwarg: arglist.append('**' + kwarg)
- decl = 'def %s(%s): print "ok %s", a, b, d, e, v, k' % (
- name, ', '.join(arglist), name)
+ decl = (('def %s(%s): print "ok %s", a, b, d, e, v, ' +
+ 'type(k) is type ("") and k or sortdict(k)')
+ % (name, ', '.join(arglist), name))
exec(decl)
func = eval(name)
funcs.append(func)
diff --git a/Lib/test/test_pyexpat.py b/Lib/test/test_pyexpat.py
index fecb27e..873dd69 100644
--- a/Lib/test/test_pyexpat.py
+++ b/Lib/test/test_pyexpat.py
@@ -5,9 +5,11 @@
from xml.parsers import expat
+from test_support import sortdict
+
class Outputter:
def StartElementHandler(self, name, attrs):
- print 'Start element:\n\t', repr(name), attrs
+ print 'Start element:\n\t', repr(name), sortdict(attrs)
def EndElementHandler(self, name):
print 'End element:\n\t', repr(name)
diff --git a/Lib/test/test_regex.py b/Lib/test/test_regex.py
index a324821..b6260d2 100644
--- a/Lib/test/test_regex.py
+++ b/Lib/test/test_regex.py
@@ -1,4 +1,4 @@
-from test_support import verbose
+from test_support import verbose, sortdict
import warnings
warnings.filterwarnings("ignore", "the regex module is deprecated",
DeprecationWarning, __name__)
@@ -40,7 +40,7 @@
print cre.group(1, 2)
print cre.group('one', 'two')
print 'realpat:', cre.realpat
-print 'groupindex:', cre.groupindex
+print 'groupindex:', sortdict(cre.groupindex)
re = 'world'
cre = regex.compile(re)
diff --git a/Lib/test/test_support.py b/Lib/test/test_support.py
index 943ba8a..330b9c8 100644
--- a/Lib/test/test_support.py
+++ b/Lib/test/test_support.py
@@ -90,6 +90,14 @@
if not condition:
raise TestFailed(reason)
+def sortdict(dict):
+ "Like repr(dict), but in sorted order."
+ items = dict.items()
+ items.sort()
+ reprpairs = ["%r: %r" % pair for pair in items]
+ withcommas = ", ".join(reprpairs)
+ return "{%s}" % withcommas
+
def check_syntax(statement):
try:
compile(statement, '<string>', 'exec')
diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index 0df8217..c82ac69 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -5,7 +5,7 @@
(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
"""#"
-from test_support import verify, verbose
+from test_support import verify, verbose, TestFailed
import sys
def test(method, input, output, *args):
@@ -493,11 +493,14 @@
'cp856', 'cp857', 'cp864', 'cp869', 'cp874',
'mac_greek', 'mac_iceland','mac_roman', 'mac_turkish',
- 'cp1006', 'cp875', 'iso8859_8',
+ 'cp1006', 'iso8859_8',
### These have undefined mappings:
#'cp424',
+ ### These fail the round-trip:
+ #'cp875'
+
):
try:
verify(unicode(s,encoding).encode(encoding) == s)