1 files changed, 104 insertions, 0 deletions
diff --git a/setuptools/installer.py b/setuptools/installer.py
new file mode 100644
index 0000000..b7096df
--- /dev/null
+++ b/setuptools/installer.py
@@ -0,0 +1,104 @@
+import glob
+import os
+import subprocess
+import sys
+import tempfile
+import warnings
+from distutils import log
+from distutils.errors import DistutilsError
+
+import pkg_resources
+from setuptools.wheel import Wheel
+from ._deprecation_warning import SetuptoolsDeprecationWarning
+
+
+def _fixup_find_links(find_links):
+    """Ensure find-links option end-up being a list of strings."""
+    if isinstance(find_links, str):
+        return find_links.split()
+    assert isinstance(find_links, (tuple, list))
+    return find_links
+
+
+def fetch_build_egg(dist, req):  # noqa: C901  # is too complex (16)  # FIXME
+    """Fetch an egg needed for building.
+
+    Use pip/wheel to fetch/build a wheel."""
+    warnings.warn(
+        "setuptools.installer is deprecated. Requirements should "
+        "be satisfied by a PEP 517 installer.",
+        SetuptoolsDeprecationWarning,
+    )
+    # Warn if wheel is not available
+    try:
+        pkg_resources.get_distribution('wheel')
+    except pkg_resources.DistributionNotFound:
+        dist.announce('WARNING: The wheel package is not available.', log.WARN)
+    # Ignore environment markers; if supplied, it is required.
+    req = strip_marker(req)
+    # Take easy_install options into account, but do not override relevant
+    # pip environment variables (like PIP_INDEX_URL or PIP_QUIET); they'll
+    # take precedence.
+    opts = dist.get_option_dict('easy_install')
+    if 'allow_hosts' in opts:
+        raise DistutilsError('the `allow-hosts` option is not supported '
+                             'when using pip to install requirements.')
+    quiet = 'PIP_QUIET' not in os.environ and 'PIP_VERBOSE' not in os.environ
+    if 'PIP_INDEX_URL' in os.environ:
+        index_url = None
+    elif 'index_url' in opts:
+        index_url = opts['index_url'][1]
+    else:
+        index_url = None
+    find_links = (
+        _fixup_find_links(opts['find_links'][1])[:] if 'find_links' in opts
+        else []
+    )
+    if dist.dependency_links:
+        find_links.extend(dist.dependency_links)
+    eggs_dir = os.path.realpath(dist.get_egg_cache_dir())
+    environment = pkg_resources.Environment()
+    for egg_dist in pkg_resources.find_distributions(eggs_dir):
+        if egg_dist in req and environment.can_add(egg_dist):
+            return egg_dist
+    with tempfile.TemporaryDirectory() as tmpdir:
+        cmd = [
+            sys.executable, '-m', 'pip',
+            '--disable-pip-version-check',
+            'wheel', '--no-deps',
+            '-w', tmpdir,
+        ]
+        if quiet:
+            cmd.append('--quiet')
+        if index_url is not None:
+            cmd.extend(('--index-url', index_url))
+        for link in find_links or []:
+            cmd.extend(('--find-links', link))
+        # If requirement is a PEP 508 direct URL, directly pass
+        # the URL to pip, as `req @ url` does not work on the
+        # command line.
+        cmd.append(req.url or str(req))
+        try:
+            subprocess.check_call(cmd)
+        except subprocess.CalledProcessError as e:
+            raise DistutilsError(str(e)) from e
+        wheel = Wheel(glob.glob(os.path.join(tmpdir, '*.whl'))[0])
+        dist_location = os.path.join(eggs_dir, wheel.egg_name())
+        wheel.install_as_egg(dist_location)
+        dist_metadata = pkg_resources.PathMetadata(
+            dist_location, os.path.join(dist_location, 'EGG-INFO'))
+        dist = pkg_resources.Distribution.from_filename(
+            dist_location, metadata=dist_metadata)
+        return dist
+
+
+def strip_marker(req):
+    """
+    Return a new requirement without the environment marker to avoid
+    calling pip with something like `babel; extra == "i18n"`, which
+    would always be ignored.
+    """
+    # create a copy to avoid mutating the input
+    req = pkg_resources.Requirement.parse(str(req))
+    req.marker = None
+    return req