Fix over-aggressive PyErr_Clear(). The same code fragment appears in
various guises in list.extend(), map(), filter(), zip(), and internally
in PySequence_Tuple().
* set_merge() cannot assume that the table doesn't resize during iteration.
* convert some unnecessary tests to asserts -- they were necessary in
dictobject.c because PyDict_Next() is a public function. The same is
not true for set_next().
* re-arrange the order of functions to more closely match the order
in dictobject.c. This makes it must easier to compare the two
and ought to simplify any issues of maintaining both.
was never called during interpreter shutdown GC, so the f_back!=NULL
assertion was correct. Now that generators get close()d during GC,
the assertion was being triggered because the generator close() was being
called as the top-level frame. However, nothing actually is broken by
this; it's just that the condition was unexpected in previous Python
versions.
a frozenset conversion when the initial search attempt fails with a
TypeError and the key is some type of set. Add a testcase.
* Eliminate a duplicate if-stmt.
s|=s, s&=s, s-=s, or s^=s). Add related tests.
* Improve names for several variables and functions.
* Provide alternate table access functions (next, contains, add, and discard)
that work with an entry argument instead of just a key. This improves
set-vs-set operations because we already have a hash value for each key
and can avoid unnecessary calls to PyObject_Hash(). Provides a 5% to 20%
speed-up for quick hashing elements like strings and integers. Provides
much more substantial improvements for slow hashing elements like tuples
or objects defining a custom __hash__() function.
* Have difference operations resize() when 1/5 of the elements are dummies.
Formerly, it was 1/6. The new ratio triggers less frequently and only
in cases that it can resize quicker and with greater benefit. The right
answer is probably either 1/4, 1/5, or 1/6. Picked the middle value for
an even trade-off between resize time and the space/time costs of dummy
entries.
* Bring in free list from dictionary code.
* Improve several comments.
* Differencing can leave many dummy entries. If more than
1/6 are dummies, then resize them away.
* Factor-out common code with new macro, PyAnySet_CheckExact.
* Give set_lookkey_string() a fast alternate path when no dummy entries
are present.
* Have set_swap_bodies() reset the hash field to -1 whenever either of
bodies is not a frozenset. Maintains the invariant of regular sets
always having -1 in the hash field; otherwise, any mutation would make
the hash value invalid.
* Use an entry pointer to simplify the code in frozenset_hash().
dictobject.c.
* Have frozenset_hash() use entry->hash instead of re-computing each
individual hash with PyObject_Hash(o);
* Finalize the dummy entry before a system exit.
- Handle both frozenset() and frozenset([]).
- Do not use singleton for frozenset subclasses.
- Finalize the singleton.
- Add test cases.
* Factor-out set_update_internal() from set_update(). Simplifies the
code for several internal callers.
* Factor constant expressions out of loop in set_merge_internal().
* Minor comment touch-ups.
In addition, long_pow() skipped a necessary (albeit extremely unlikely
to trigger) error check when converting an int modulus to long.
Alas, I was unable to write a test case that crashed due to either
cause.
Bugfix candidate.
[ 1229429 ] missing Py_DECREF in PyObject_CallMethod
Add a test in test_enumerate, which is a bit random, but suffices
(reversed_new calls PyObject_CallMethod under some circumstances).
managed by C, because it's possible for the block to be smaller than the
new requested size, and at the end of allocated VM. Trying to copy over
nbytes bytes to a Python small-object block can segfault then, and there's
no portable way to avoid this (we would have to know how many bytes
starting at p are addressable, and std C has no means to determine that).
Bugfix candidate. Should be backported to 2.4, but I'm out of time.
[ 1181301 ] make float packing copy bytes when they can
which hasn't been reviewed, despite numerous threats to check it in
anyway if noone reviews it. Please read the diff on the checkin list,
at least!
The basic idea is to examine the bytes of some 'probe values' to see if
the current platform is a IEEE 754-ish platform, and if so
_PyFloat_{Pack,Unpack}{4,8} just copy bytes around.
The rest is hair for testing, and tests.
conversion using the proper magic slot (e.g., __int__()). Also move conversion
code out of PyNumber_*() functions in the C API into the nb_* function.
Applied patch #1109424. Thanks Walter Doewald.
[ 1165306 ] Property access with decorator makes interpreter crash
Don't allow the creation of unbound methods with NULL im_class, because
attempting to call such crashes.
Backport candidate.
* Speed-up "x in y" where x has more than one character.
The existing code made excessive calls to the expensive memcmp() function.
The new code uses memchr() to rapidly find a start point for memcmp().
In addition to knowing that the first character is a match, the new code
also checks that the last character is a match. This significantly reduces
the incidence of false starts (saving memcmp() calls and making quadratic
behavior less likely).
Improves the timings on:
python -m timeit -r7 -s"x='a'*1000" "'ab' in x"
python -m timeit -r7 -s"x='a'*1000" "'bc' in x"
Once this code has proven itself, then string_find_internal() should refer
to it rather than running its own version. Also, something similar may
apply to unicode objects.
[ 1124295 ] Function's __name__ no longer accessible in restricted mode
which I introduced with a bit of mindless copy-paste when making
__name__ writable. You can't assign to __name__ in restricted mode,
which I'm going to pretend was intentional :)