Trac #30984: sage_setup: Replace imports from distutils by setuptools

... in anticipation of the `distutils` deprecation
(https://www.python.org/dev/peps/pep-0632/)

From https://setuptools.readthedocs.io/en/latest/deprecated/distutils-
legacy.html

- `distutils.core.setup` → `setuptools.setup`
- `distutils.cmd.Command` → `setuptools.Command`
- `distutils.log` → `(no replacement yet)`
- `distutils.version.*` → `packaging.version.*`

"If a project relies on uses of distutils that do not have a suitable
replacement above, please search the Setuptools issue tracker and file a
request, describing the use-case so that Setuptools’ maintainers can
investigate."

Part of #31295 (Meta-ticket: Replace imports from deprecated distutils)

URL: https://trac.sagemath.org/30984
Reported by: mkoeppe
Ticket author(s): Frédéric Chapoton, Matthias Koeppe
Reviewer(s): Matthias Koeppe, John Palmieri

Author: Release Manager

src/sage_setup/command/sage_build.py

@@ -1,3 +1,7 @@
+# Import setuptools before importing distutils, so that setuptools
+# can replace distutils by its own vendored copy.
+import setuptools
+
 from distutils import log
 from distutils.command.build import build
 

src/sage_setup/command/sage_build_cython.py

@@ -8,10 +8,13 @@
 import sys
 import time
 import json
+
+# Import setuptools before importing distutils, so that setuptools
+# can replace distutils by its own vendored copy.
+import setuptools
+
 from distutils import log
-from distutils.cmd import Command
-from distutils.errors import (DistutilsModuleError,
-                              DistutilsOptionError)
+from setuptools import Command
 
 from sage_setup.util import stable_uniq
 from sage_setup.find import find_extra_files
@@ -130,12 +133,12 @@ def finalize_options(self):
         try:
             self.parallel = int(self.parallel)
         except ValueError:
-            raise DistutilsOptionError("parallel should be an integer")
+            raise ValueError("parallel should be an integer")
 
         try:
             import Cython
         except ImportError:
-            raise DistutilsModuleError(
+            raise ImportError(
                 "Cython must be installed and importable in order to run "
                 "the cythonize command")
 

src/sage_setup/command/sage_build_ext.py

@@ -1,7 +1,12 @@
 import os
 import errno
+
+# Import setuptools before importing distutils, so that setuptools
+# can replace distutils by its own vendored copy.
+import setuptools
+
 from distutils import log
-from distutils.command.build_ext import build_ext
+from setuptools.command.build_ext import build_ext
 from distutils.dep_util import newer_group
 from distutils.errors import DistutilsSetupError
 from sage_setup.run_parallel import execute_list_of_commands

src/sage_setup/command/sage_install.py

@@ -4,6 +4,11 @@
 
 import os
 import time
+
+# Import setuptools before importing distutils, so that setuptools
+# can replace distutils by its own vendored copy.
+import setuptools
+
 from distutils import log
 from distutils.command.install import install
 

src/sage_setup/find.py

@@ -1,16 +1,15 @@
 """
 Recursive Directory Contents
 """
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2014 Volker Braun <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
 #                  http://www.gnu.org/licenses/
-#*****************************************************************************
-
+# ****************************************************************************
 
 import importlib.machinery
 import importlib.util
@@ -19,6 +18,7 @@
 
 from collections import defaultdict
 
+
 def read_distribution(src_file):
     """
     Parse ``src_file`` for a ``# sage_setup: distribution = PKG`` directive.
@@ -58,6 +58,7 @@ def read_distribution(src_file):
                     return value
     return ''
 
+
 def find_python_sources(src_dir, modules=['sage'], distributions=None):
     """
     Find all Python packages and Python/Cython modules in the sources.
@@ -115,7 +116,7 @@ def find_python_sources(src_dir, modules=['sage'], distributions=None):
     Filtering by distribution (distutils package)::
 
         sage: find_python_sources(SAGE_SRC, distributions=['sage-tdlib'])
-        ([], [], [<distutils.extension.Extension('sage.graphs.graph_decompositions.tdlib')...>])
+        ([], [], [<setuptools.extension.Extension('sage.graphs.graph_decompositions.tdlib')...>])
 
     Benchmarking::
 
@@ -130,7 +131,7 @@ def find_python_sources(src_dir, modules=['sage'], distributions=None):
         sage: find_python_sources(SAGE_SRC, modules=['sage_setup'])
         (['sage_setup', ...], [...'sage_setup.find'...], [])
     """
-    from distutils.extension import Extension
+    from setuptools import Extension
 
     PYMOD_EXT = get_extensions('source')[0]
     INIT_FILE = '__init__' + PYMOD_EXT
@@ -172,6 +173,7 @@ def is_in_distributions(filename):
         os.chdir(cwd)
     return python_packages, python_modules, cython_modules
 
+
 def find_extra_files(src_dir, modules, cythonized_dir, special_filenames=[]):
     """
     Find all extra files which should be installed.

src/sage_setup/optional_extension.py

@@ -7,18 +7,17 @@
 package which must be installed.
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2015 Jeroen Demeyer <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
-
-from distutils.extension import Extension
+from setuptools.extension import Extension
 from sage.misc.package import list_packages
 
 all_packages = list_packages(local=True)
@@ -40,6 +39,7 @@ class CythonizeExtension(Extension):
     """
     skip_build = True
 
+
 def is_package_installed_and_updated(pkg):
     from sage.misc.package import is_package_installed
     try:
@@ -51,6 +51,7 @@ def is_package_installed_and_updated(pkg):
         condition = (pkginfo["installed_version"] == pkginfo["remote_version"])
     return condition
 
+
 def OptionalExtension(*args, **kwds):
     """
     If some condition (see INPUT) is satisfied, return an ``Extension``.