swig/Examples/python/extend
William S Fulton 2598574915 Complete the Python 2 removal and fix issues found reviewing it
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)
2026-07-06 23:50:31 +01:00
..
Makefile Complete the Python 2 removal and fix issues found reviewing it 2026-07-06 23:50:31 +01:00
example.cxx Minor tidyup mods 2003-09-08 22:07:49 +00:00
example.h Fix compiler warnings in examples when using -std=c++98 -std=gnu89 -pedantic -Wreturn-type 2014-05-24 13:13:32 +01:00
example.i Minor tidyup mods 2003-09-08 22:07:49 +00:00
index.html Remove cvs $Header$ 2007-10-17 21:47:25 +00:00
runme.py Modify examples to be both Python 2 and 3 compatible 2020-08-15 16:46:01 +01:00