Implement PEP 660 allowing both "strict" and "lax/loose" approaches

bootstrap.egg-info/entry_points.txt

@@ -2,6 +2,7 @@
 egg_info = setuptools.command.egg_info:egg_info
 build_py = setuptools.command.build_py:build_py
 sdist = setuptools.command.sdist:sdist
+editable_wheel = setuptools.command.editable_wheel:editable_wheel
 
 [distutils.setup_keywords]
 include_package_data = setuptools.dist:assert_bool

setup.cfg

@@ -113,6 +113,7 @@ distutils.commands =
 	develop = setuptools.command.develop:develop
 	dist_info = setuptools.command.dist_info:dist_info
 	easy_install = setuptools.command.easy_install:easy_install
+	editable_wheel = setuptools.command.editable_wheel:editable_wheel
 	egg_info = setuptools.command.egg_info:egg_info
 	install = setuptools.command.install:install
 	install_egg_info = setuptools.command.install_egg_info:install_egg_info

setuptools/build_meta.py

@@ -46,6 +46,8 @@
            'prepare_metadata_for_build_wheel',
            'build_wheel',
            'build_sdist',
+           'get_requires_for_build_editable',
+           'build_editable',
            '__legacy__',
            'SetupRequirementsError']
 
@@ -183,7 +185,7 @@ def get_requires_for_build_sdist(self, config_settings=None):
     def prepare_metadata_for_build_wheel(self, metadata_directory,
                                          config_settings=None):
         sys.argv = sys.argv[:1] + [
-            'dist_info', '--egg-base', metadata_directory]
+            'dist_info', '--output-dir', metadata_directory]
         with no_install_setup_requires():
             self.run_setup()
 
@@ -249,6 +251,28 @@ def build_sdist(self, sdist_directory, config_settings=None):
                                          '.tar.gz', sdist_directory,
                                          config_settings)
 
+    # PEP660 hooks:
+    # build_editable
+    # get_requires_for_build_editable
+    # prepare_metadata_for_build_editable
+    def build_editable(
+        self, wheel_directory, config_settings=None, metadata_directory=None
+    ):
+        # XXX can or should we hide our editable_wheel command normally?
+        return self._build_with_temp_dir(
+            ["editable_wheel", "--dist-info-dir", metadata_directory],
+            ".whl", wheel_directory, config_settings
+        )
+
+    def get_requires_for_build_editable(self, config_settings=None):
+        return self.get_requires_for_build_wheel(config_settings)
+
+    def prepare_metadata_for_build_editable(self, metadata_directory,
+                                            config_settings=None):
+        return self.prepare_metadata_for_build_wheel(
+            metadata_directory, config_settings
+        )
+
 
 class _BuildMetaLegacyBackend(_BuildMetaBackend):
     """Compatibility backend for setuptools
@@ -295,9 +319,12 @@ def run_setup(self, setup_script='setup.py'):
 
 get_requires_for_build_wheel = _BACKEND.get_requires_for_build_wheel
 get_requires_for_build_sdist = _BACKEND.get_requires_for_build_sdist
+get_requires_for_build_editable = _BACKEND.get_requires_for_build_editable
 prepare_metadata_for_build_wheel = _BACKEND.prepare_metadata_for_build_wheel
+prepare_metadata_for_build_editable = _BACKEND.prepare_metadata_for_build_editable
 build_wheel = _BACKEND.build_wheel
 build_sdist = _BACKEND.build_sdist
+build_editable = _BACKEND.build_editable
 
 
 # The legacy backend

setuptools/command/build_ext.py

@@ -3,7 +3,6 @@
 import itertools
 from importlib.machinery import EXTENSION_SUFFIXES
 from distutils.command.build_ext import build_ext as _du_build_ext
-from distutils.file_util import copy_file
 from distutils.ccompiler import new_compiler
 from distutils.sysconfig import customize_compiler, get_config_var
 from distutils.errors import DistutilsError
@@ -96,10 +95,7 @@ def copy_extensions_to_source(self):
             # Always copy, even if source is older than destination, to ensure
             # that the right extensions for the current Python/platform are
             # used.
-            copy_file(
-                src_filename, dest_filename, verbose=self.verbose,
-                dry_run=self.dry_run
-            )
+            build_py.copy_file(src_filename, dest_filename)
             if ext._needs_stub:
                 self.write_stub(package_dir or os.curdir, ext, True)
 

setuptools/command/build_py.py

@@ -36,6 +36,17 @@ def finalize_options(self):
         if 'data_files' in self.__dict__:
             del self.__dict__['data_files']
         self.__updated_files = []
+        self.use_links = None
+
+    def copy_file(self, infile, outfile, preserve_mode=1, preserve_times=1,
+                  link=None, level=1):
+        # Overwrite base class to allow using links
+        link = getattr(self, "use_links", None) if link is None else link
+        if link:
+            infile = str(Path(infile).resolve())
+            outfile = str(Path(outfile).resolve())
+        return super().copy_file(infile, outfile, preserve_mode,
+                                 preserve_times, link, level)
 
     def run(self):
         """Build modules, packages, and copy data files to build directory"""

setuptools/command/dist_info.py

@@ -7,10 +7,12 @@
 import re
 import warnings
 from inspect import cleandoc
+from pathlib import Path
 
 from distutils.core import Command
 from distutils import log
 from setuptools.extern import packaging
+from setuptools._deprecation_warning import SetuptoolsDeprecationWarning
 
 
 class dist_info(Command):
@@ -19,28 +21,46 @@ class dist_info(Command):
 
     user_options = [
         ('egg-base=', 'e', "directory containing .egg-info directories"
-                           " (default: top of the source tree)"),
+                           " (default: top of the source tree)"
+                           " DEPRECATED: use --output-dir."),
+        ('output-dir=', 'o', "directory inside of which the .dist-info will be"
+                             "created (default: top of the source tree)"),
     ]
 
     def initialize_options(self):
         self.egg_base = None
+        self.output_dir = None
+        self.name = None
+        self.dist_info_dir = None
 
     def finalize_options(self):
-        pass
+        if self.egg_base:
+            msg = "--egg-base is deprecated for dist_info command. Use --output-dir."
+            warnings.warn(msg, SetuptoolsDeprecationWarning)
+            self.output_dir = self.egg_base or self.output_dir
 
-    def run(self):
-        egg_info = self.get_finalized_command('egg_info')
-        egg_info.egg_base = self.egg_base
+        dist = self.distribution
+        project_dir = dist.src_root or os.curdir
+        self.output_dir = Path(self.output_dir or project_dir)
+
+        egg_info = self.reinitialize_command('egg_info')
+        egg_info.egg_base = str(self.output_dir)
         egg_info.finalize_options()
-        egg_info.run()
-        name = _safe(self.distribution.get_name())
-        version = _version(self.distribution.get_version())
-        base = self.egg_base or os.curdir
-        dist_info_dir = os.path.join(base, f"{name}-{version}.dist-info")
-        log.info("creating '{}'".format(os.path.abspath(dist_info_dir)))
+        self.egg_info = egg_info
 
+        name = _safe(dist.get_name())
+        version = _version(dist.get_version())
+        self.name = f"{name}-{version}"
+        self.dist_info_dir = os.path.join(self.output_dir, f"{self.name}.dist-info")
+
+    def run(self):
+        self.output_dir.mkdir(parents=True, exist_ok=True)
+        self.egg_info.run()
+        egg_info_dir = self.egg_info.egg_info
+        log.info("creating '{}'".format(os.path.abspath(self.dist_info_dir)))
         bdist_wheel = self.get_finalized_command('bdist_wheel')
-        bdist_wheel.egg2dist(egg_info.egg_info, dist_info_dir)
+        bdist_wheel.egg2dist(egg_info_dir, self.dist_info_dir)
+        assert os.path.exists(egg_info_dir) is False
 
 
 def _safe(component: str) -> str: