bpo-30863: Rewrite PyUnicode_AsWideChar() and PyUnicode_AsWideCharString(). #2599
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…ing(). They no longer cache the wchar_t* representation of string objects.
Misc/NEWS
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| C API | ||
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| - bpo-30863: PyUnicode_AsWideChar() and PyUnicode_AsWideCharString() no longer |
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I think this should change to use blurb.
Objects/unicodeobject.c
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| Py_ssize_t res; | ||
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| assert(unicode != NULL); | ||
| assert(PyUnicode_IS_READY(unicode)); |
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Can't we get not ready string here? IMHO it should be put after the following if block.
Objects/unicodeobject.c
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| "embedded null character"); | ||
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| buflen = unicode_get_widechar_size(unicode); | ||
| if (buflen < 0) { |
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Why could it be < 0? It looks to me assert(buflen >= 0) is right.
Objects/unicodeobject.c
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| } | ||
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| buffer = PyMem_NEW(wchar_t, buflen + 1); | ||
| buffer = (wchar_t *) PyMem_MALLOC(sizeof(wchar_t) * (buflen + 1)); |
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Do we need overflow check here?
Objects/unicodeobject.c
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| memcpy(w, wstr, size * sizeof(wchar_t)); | ||
| return; | ||
| } | ||
| assert(PyUnicode_KIND(unicode) != SIZEOF_WCHAR_T); |
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I'd suggest remove this assertion since we have two more specific assertions below and they are easier to read and understand.
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Both. Deprecating |
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No. I just mean if that's also a goal, it's better to mention it in the NEWS. Currently the NEWS takes removing the cache as the only goal. |
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If deprecating |
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I mean something like
Is it acceptable to you? If not, doesn't matter, just merge it since the code already LGTM. :-) |
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@serhiy-storchaka and @zhangyangyu: ping |
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I was going to discuss this change on Python-Dev first. |
https://mail.python.org/pipermail/python-dev/2018-October/155530.html |
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I started a new Pipelines build at https://dev.azure.com/python/cpython/_build/results?buildId=32792&view=logs to get a first check on whether there are significant performance regressions in the test suite. If it comes out about equal (with, say, this recent build), then I have no concerns. |
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Looks good to me 👍 |
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Thanks @serhiy-storchaka and @zooba: I wanted to do this change since Python 3.3 :-) I already attempted to make this change previously, but I failed. Mostly, because the legacy API was still very popular. |
10 participants
They no longer cache the
wchar_t*representation of string objects.https://bugs.python.org/issue30863