for 'str' and 'unicode', and can be used instead of
types.StringTypes, e.g. to test whether something is "a string":
isinstance(x, string) is True for Unicode and 8-bit strings. This
is an abstract base class and cannot be instantiated directly.
don't understand how this function works, also beefed up the docs. The
most common usage error is of this form (often spread out across gotos):
if (_PyString_Resize(&s, n) < 0) {
Py_DECREF(s);
s = NULL;
goto outtahere;
}
The error is that if _PyString_Resize runs out of memory, it automatically
decrefs the input string object s (which also deallocates it, since its
refcount must be 1 upon entry), and sets s to NULL. So if the "if"
branch ever triggers, it's an error to call Py_DECREF(s): s is already
NULL! A correct way to write the above is the simpler (and intended)
if (_PyString_Resize(&s, n) < 0)
goto outtahere;
Bugfix candidate.
This implements ideas from Marc-Andre, Martin, Guido and me on Python-Dev.
"Short" Unicode strings are encoded into a "big enough" stack buffer,
then exactly as much string space as they turn out to need is allocated
at the end. This should have speed benefits akin to Martin's "measure
once, allocate once" strategy, but without needing a distinct measuring
pass.
"Long" Unicode strings allocate as much heap space as they could possibly
need (4 x # Unicode chars), and do a realloc at the end to return the
untouched excess. Since the overallocation is likely to be substantial,
this shouldn't burden the platform realloc with unusably small excess
blocks.
Also simplified uses of the PyString_xyz functions. Also added a release-
build check that 4*size doesn't overflow a C int. Sooner or later, that's
going to happen.
http://www.python.org/sf/444708
This adds the optional argument for str.strip
to unicode.strip too and makes it possible
to call str.strip with a unicode argument
and unicode.strip with a str argument.
pointers is a signed type. Changing "allocated" to a signed int makes
undetected overflow more likely, but there was no overflow detection
before either.
Add a method zfill to str, unicode and UserString and change
Lib/string.py accordingly.
This activates the zfill version in unicodeobject.c that was
commented out and implements the same in stringobject.c. It also
adds the test for unicode support in Lib/string.py back in and
uses repr() instead() of str() (as it was before Lib/string.py 1.62)
PEP 285. Everything described in the PEP is here, and there is even
some documentation. I had to fix 12 unit tests; all but one of these
were printing Boolean outcomes that changed from 0/1 to False/True.
(The exception is test_unicode.py, which did a type(x) == type(y)
style comparison. I could've fixed that with a single line using
issubtype(x, type(y)), but instead chose to be explicit about those
places where a bool is expected.
Still to do: perhaps more documentation; change standard library
modules to return False/True from predicates.
Objects/
fileobject.c
stringobject.c
unicodeobject.c
This commit doesn't include the cleanup patches for stringobject.c and
unicodeobject.c which are shown separately in the patch manager. Those
patches will be regenerated and applied in a subsequent commit, so as
to preserve a fallback position (this commit to those files).
Fix for the UTF-8 decoder: it will now accept isolated surrogates
(previously it raised an exception which causes round-trips to
fail).
Added new tests for UTF-8 round-trip safety (we rely on UTF-8 for
marshalling Unicode objects, so we better make sure it works for
all Unicode code points, including isolated surrogates).
Bumped the PYC magic in a non-standard way -- please review. This
was needed because the old PYC format used illegal UTF-8 sequences
for isolated high surrogates which now raise an exception.
This is best reproduced by
while 1:
class U(unicode):
pass
U(u"xxxxxx")
The unicode_dealloc() code wasn't properly freeing the str and defenc
fields of the Unicode object when freeing a subtype instance. Fixed
this by a subtle refactoring that actually reduces the amount of code
slightly.
This patch implements what we have discussed on python-dev late in
September: str(obj) and unicode(obj) should behave similar, while
the old behaviour is retained for unicode(obj, encoding, errors).
The patch also adds a new feature with which objects can provide
unicode(obj) with input data: the __unicode__ method. Currently no
new tp_unicode slot is implemented; this is left as option for the
future.
Note that PyUnicode_FromEncodedObject() no longer accepts Unicode
objects as input. The API name already suggests that Unicode
objects do not belong in the list of acceptable objects and the
functionality was only needed because
PyUnicode_FromEncodedObject() was being used directly by
unicode(). The latter was changed in the discussed way:
* unicode(obj) calls PyObject_Unicode()
* unicode(obj, encoding, errors) calls PyUnicode_FromEncodedObject()
One thing left open to discussion is whether to leave the
PyUnicode_FromObject() API as a thin API extension on top of
PyUnicode_FromEncodedObject() or to turn it into a (macro) alias
for PyObject_Unicode() and deprecate it. Doing so would have some
surprising consequences though, e.g. u"abc" + 123 would turn out
as u"abc123"...
[Marc-Andre didn't have time to check this in before the deadline. I
hope this is OK, Marc-Andre! You can still make changes and commit
them on the trunk after the branch has been made, but then please mail
Barry a context diff if you want the change to be merged into the
2.2b1 release branch. GvR]
many types were subclassable but had a xxx_dealloc function that
called PyObject_DEL(self) directly instead of deferring to
self->ob_type->tp_free(self). It is permissible to set tp_free in the
type object directly to _PyObject_Del, for non-GC types, or to
_PyObject_GC_Del, for GC types. Still, PyObject_DEL was a tad faster,
so I'm fearing that our pystone rating is going down again. I'm not
sure if doing something like
void xxx_dealloc(PyObject *self)
{
if (PyXxxCheckExact(self))
PyObject_DEL(self);
else
self->ob_type->tp_free(self);
}
is any faster than always calling the else branch, so I haven't
attempted that -- however those types whose own dealloc is fancier
(int, float, unicode) do use this pattern.
elements which are not Unicode objects or strings. (This matches
the string.join() behaviour.)
Fix a memory leak in the .join() method which occurs in case
the Unicode resize fails.
Restore the test_unicode output.
+ These were leaving the hash fields at 0, which all string and unicode
routines believe is a legitimate hash code. As a result, hash() applied
to str and unicode subclass instances always returned 0, which in turn
confused dict operations, etc.
+ Changed local names "new"; no point to antagonizing C++ compilers.
Removed all instances of Py_UCS2 from the codebase, and so also (I hope)
the last remaining reliance on the platform having an integral type
with exactly 16 bits.
PyUnicode_DecodeUTF16() and PyUnicode_EncodeUTF16() now read and write
one byte at a time.
And remove all the extern decls in the middle of .c files.
Apparently, it was excluded from the header file because it is
intended for internal use by the interpreter. It's still intended for
internal use and documented as such in the header file.
#caused warnings with the VMS C compiler. (SF bug #442998, in part.)
On a narrow system the current code should never be executed since ch
will always be < 0x10000.
Marc-Andre: you may end up fixing this a different way, since I
believe you have plans to generate \U for surrogate pairs. I'll leave
that to you.