--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/python3.8/site-packages/setuptools/command/build_py.py	Mon Jul 27 03:47:31 2020 -0400
@@ -0,0 +1,270 @@
+from glob import glob
+from distutils.util import convert_path
+import distutils.command.build_py as orig
+import os
+import fnmatch
+import textwrap
+import io
+import distutils.errors
+import itertools
+
+from setuptools.extern import six
+from setuptools.extern.six.moves import map, filter, filterfalse
+
+try:
+    from setuptools.lib2to3_ex import Mixin2to3
+except ImportError:
+
+    class Mixin2to3:
+        def run_2to3(self, files, doctests=True):
+            "do nothing"
+
+
+class build_py(orig.build_py, Mixin2to3):
+    """Enhanced 'build_py' command that includes data files with packages
+
+    The data files are specified via a 'package_data' argument to 'setup()'.
+    See 'setuptools.dist.Distribution' for more details.
+
+    Also, this version of the 'build_py' command allows you to specify both
+    'py_modules' and 'packages' in the same setup operation.
+    """
+
+    def finalize_options(self):
+        orig.build_py.finalize_options(self)
+        self.package_data = self.distribution.package_data
+        self.exclude_package_data = (self.distribution.exclude_package_data or
+                                     {})
+        if 'data_files' in self.__dict__:
+            del self.__dict__['data_files']
+        self.__updated_files = []
+        self.__doctests_2to3 = []
+
+    def run(self):
+        """Build modules, packages, and copy data files to build directory"""
+        if not self.py_modules and not self.packages:
+            return
+
+        if self.py_modules:
+            self.build_modules()
+
+        if self.packages:
+            self.build_packages()
+            self.build_package_data()
+
+        self.run_2to3(self.__updated_files, False)
+        self.run_2to3(self.__updated_files, True)
+        self.run_2to3(self.__doctests_2to3, True)
+
+        # Only compile actual .py files, using our base class' idea of what our
+        # output files are.
+        self.byte_compile(orig.build_py.get_outputs(self, include_bytecode=0))
+
+    def __getattr__(self, attr):
+        "lazily compute data files"
+        if attr == 'data_files':
+            self.data_files = self._get_data_files()
+            return self.data_files
+        return orig.build_py.__getattr__(self, attr)
+
+    def build_module(self, module, module_file, package):
+        if six.PY2 and isinstance(package, six.string_types):
+            # avoid errors on Python 2 when unicode is passed (#190)
+            package = package.split('.')
+        outfile, copied = orig.build_py.build_module(self, module, module_file,
+                                                     package)
+        if copied:
+            self.__updated_files.append(outfile)
+        return outfile, copied
+
+    def _get_data_files(self):
+        """Generate list of '(package,src_dir,build_dir,filenames)' tuples"""
+        self.analyze_manifest()
+        return list(map(self._get_pkg_data_files, self.packages or ()))
+
+    def _get_pkg_data_files(self, package):
+        # Locate package source directory
+        src_dir = self.get_package_dir(package)
+
+        # Compute package build directory
+        build_dir = os.path.join(*([self.build_lib] + package.split('.')))
+
+        # Strip directory from globbed filenames
+        filenames = [
+            os.path.relpath(file, src_dir)
+            for file in self.find_data_files(package, src_dir)
+        ]
+        return package, src_dir, build_dir, filenames
+
+    def find_data_files(self, package, src_dir):
+        """Return filenames for package's data files in 'src_dir'"""
+        patterns = self._get_platform_patterns(
+            self.package_data,
+            package,
+            src_dir,
+        )
+        globs_expanded = map(glob, patterns)
+        # flatten the expanded globs into an iterable of matches
+        globs_matches = itertools.chain.from_iterable(globs_expanded)
+        glob_files = filter(os.path.isfile, globs_matches)
+        files = itertools.chain(
+            self.manifest_files.get(package, []),
+            glob_files,
+        )
+        return self.exclude_data_files(package, src_dir, files)
+
+    def build_package_data(self):
+        """Copy data files into build directory"""
+        for package, src_dir, build_dir, filenames in self.data_files:
+            for filename in filenames:
+                target = os.path.join(build_dir, filename)
+                self.mkpath(os.path.dirname(target))
+                srcfile = os.path.join(src_dir, filename)
+                outf, copied = self.copy_file(srcfile, target)
+                srcfile = os.path.abspath(srcfile)
+                if (copied and
+                        srcfile in self.distribution.convert_2to3_doctests):
+                    self.__doctests_2to3.append(outf)
+
+    def analyze_manifest(self):
+        self.manifest_files = mf = {}
+        if not self.distribution.include_package_data:
+            return
+        src_dirs = {}
+        for package in self.packages or ():
+            # Locate package source directory
+            src_dirs[assert_relative(self.get_package_dir(package))] = package
+
+        self.run_command('egg_info')
+        ei_cmd = self.get_finalized_command('egg_info')
+        for path in ei_cmd.filelist.files:
+            d, f = os.path.split(assert_relative(path))
+            prev = None
+            oldf = f
+            while d and d != prev and d not in src_dirs:
+                prev = d
+                d, df = os.path.split(d)
+                f = os.path.join(df, f)
+            if d in src_dirs:
+                if path.endswith('.py') and f == oldf:
+                    continue  # it's a module, not data
+                mf.setdefault(src_dirs[d], []).append(path)
+
+    def get_data_files(self):
+        pass  # Lazily compute data files in _get_data_files() function.
+
+    def check_package(self, package, package_dir):
+        """Check namespace packages' __init__ for declare_namespace"""
+        try:
+            return self.packages_checked[package]
+        except KeyError:
+            pass
+
+        init_py = orig.build_py.check_package(self, package, package_dir)
+        self.packages_checked[package] = init_py
+
+        if not init_py or not self.distribution.namespace_packages:
+            return init_py
+
+        for pkg in self.distribution.namespace_packages:
+            if pkg == package or pkg.startswith(package + '.'):
+                break
+        else:
+            return init_py
+
+        with io.open(init_py, 'rb') as f:
+            contents = f.read()
+        if b'declare_namespace' not in contents:
+            raise distutils.errors.DistutilsError(
+                "Namespace package problem: %s is a namespace package, but "
+                "its\n__init__.py does not call declare_namespace()! Please "
+                'fix it.\n(See the setuptools manual under '
+                '"Namespace Packages" for details.)\n"' % (package,)
+            )
+        return init_py
+
+    def initialize_options(self):
+        self.packages_checked = {}
+        orig.build_py.initialize_options(self)
+
+    def get_package_dir(self, package):
+        res = orig.build_py.get_package_dir(self, package)
+        if self.distribution.src_root is not None:
+            return os.path.join(self.distribution.src_root, res)
+        return res
+
+    def exclude_data_files(self, package, src_dir, files):
+        """Filter filenames for package's data files in 'src_dir'"""
+        files = list(files)
+        patterns = self._get_platform_patterns(
+            self.exclude_package_data,
+            package,
+            src_dir,
+        )
+        match_groups = (
+            fnmatch.filter(files, pattern)
+            for pattern in patterns
+        )
+        # flatten the groups of matches into an iterable of matches
+        matches = itertools.chain.from_iterable(match_groups)
+        bad = set(matches)
+        keepers = (
+            fn
+            for fn in files
+            if fn not in bad
+        )
+        # ditch dupes
+        return list(_unique_everseen(keepers))
+
+    @staticmethod
+    def _get_platform_patterns(spec, package, src_dir):
+        """
+        yield platform-specific path patterns (suitable for glob
+        or fn_match) from a glob-based spec (such as
+        self.package_data or self.exclude_package_data)
+        matching package in src_dir.
+        """
+        raw_patterns = itertools.chain(
+            spec.get('', []),
+            spec.get(package, []),
+        )
+        return (
+            # Each pattern has to be converted to a platform-specific path
+            os.path.join(src_dir, convert_path(pattern))
+            for pattern in raw_patterns
+        )
+
+
+# from Python docs
+def _unique_everseen(iterable, key=None):
+    "List unique elements, preserving order. Remember all elements ever seen."
+    # unique_everseen('AAAABBBCCDAABBB') --> A B C D
+    # unique_everseen('ABBCcAD', str.lower) --> A B C D
+    seen = set()
+    seen_add = seen.add
+    if key is None:
+        for element in filterfalse(seen.__contains__, iterable):
+            seen_add(element)
+            yield element
+    else:
+        for element in iterable:
+            k = key(element)
+            if k not in seen:
+                seen_add(k)
+                yield element
+
+
+def assert_relative(path):
+    if not os.path.isabs(path):
+        return path
+    from distutils.errors import DistutilsSetupError
+
+    msg = textwrap.dedent("""
+        Error: setup script specifies an absolute path:
+
+            %s
+
+        setup() arguments must *always* be /-separated paths relative to the
+        setup.py directory, *never* absolute paths.
+        """).lstrip() % path
+    raise DistutilsSetupError(msg)