Follow-up work on top of the initial Python 2.x removal: it finishes the
removal and fixes several issues found while reviewing the change.
Correctness fixes:
- pyrun.swg: SwigPyPacked_str passed the type name straight to
PyUnicode_FromFormat as its format string, so a type name containing a
'%' would be misinterpreted. Use PyUnicode_FromString instead.
- Doc/Manual/Varargs.html: the (...) varargs freearg typemap example lost
its free() loop when the surrounding Python 2 guard was removed, leaking
the memory the in typemap allocates. Restore the loop, now unconditional.
- Doc/Manual/Typemaps.html: the PyInt_Check to PyLong_Check substitution
left two typecheck excerpts reading PyLong_Check || PyLong_Check; collapse
each back to a single check.
Code generator (Source/Modules/python.cxx):
- Emit the native class X(..., metaclass=_SwigNonDynamicMeta) form for
nondynamic classes in all three base-list branches (object, Exception and
explicit bases), and drop the Python 2 _swig_add_metaclass helper.
- Emit a plain import builtins as __builtin__ instead of the Python 2
try/except import fallback.
- Update a stale Python 2.x comment.
Remove the deprecated embed.i library (it only ever worked with Python 2):
- Delete Lib/python/embed.i and the Lib/python/Makefile.in reference to it.
- Remove the python_static and python_static_cpp targets from
Examples/Makefile.in and the now-orphaned static: targets that used them
from the Examples/python example Makefiles.
- Remove the embed.i section from the manual.
Python test suite (Examples/test-suite/python):
- profiletest_runme.py: convert the Python 2 print statements to print().
- doxygen_constructors_runme.py: drop the dead sys.version_info < (3, 0)
branch, keeping the Python 3 super().__init__() form.
- li_cdata_bytes_runme.py and li_cdata_bytes_cpp_runme.py: drop the dead
exit-on-Python-2 version guard.
- file_test_runme.py and python_abstractbase_runme.py: drop the now-unused
import sys left behind by guard removal.
Documentation (Doc/Manual/Python.html):
- Drop the embed.i and SWIG_PYTHON_STRICT_UNICODE_WCHAR sections; the latter
macro was Python 2 only and no longer exists, wide strings are unicode-only
by default.
- De-duplicate the %pythonabc example and drop a stale collections.abc
compatibility note.
- Update the version support statement and other stale Python 2 mentions.
Other cleanups:
- Tools/mkdist.py: raise the minimum Python version check to Python 3.
- Reword stale Python 2 comments in pyrun.swg, pyiterators.swg and
pycontainer.swg, and fix a PyString_FromFormat left in a pyclasses.swg
doc comment.
- CHANGES.current: record that Python 2 support has been dropped.
Assisted-by: Claude Code (Opus 4.8)
Found via `codespell -q 3 -L ans,anumber,ba,bae,chello,clos,cmo,coo,dout,fo,funktion,goin,inout,methid,nd,nin,nnumber,object,objekt,od,ois,packag,parm,parms,pres,statics,strack,struc,tempdate,te,thru,uint,upto,writen`
Only one import of the low-level C/C++ module from the pure Python module is
attempted now. Previously a second import of the low-level C/C++ module was attempted
after an ImportError occurred and was done to support 'split modules'. A 'split module' is
a configuration where the pure Python module is a module within a Python package and the
low-level C/C++ module is a global Python module. Now a 'split module' configuration is
no longer supported by default. This configuration can be supported with a simple
customization, such as:
%module(package="mypackage", moduleimport="import $module") foo
or if using -builtin:
%module(package="mypackage", moduleimport="from $module import *") foo
instead of
%module(package="mypackage") foo
See the updated Python chapter titled "Location of modules" in the documentation.
Closes#848#1343
Getting these kind of errors on Appveyor which uses mingw/cygwin to run
a Python interpreter:
Native windows Python 3.6 running under cygwin and mingw Python 3.7 running under mingw:
Fatal Python error: _Py_HashRandomization_Init: failed to get random
numbers to initialize Python
Cygwin Python 2.7 running under cygwin:
0 [main] python2.7 496 child_info_fork::abort: address space needed by '_foo.dll' (0x6D0000)
is already occupied
William S Fulton