--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/planemo/lib/python3.7/site-packages/pip/_internal/operations/prepare.py	Fri Jul 31 00:32:28 2020 -0400
@@ -0,0 +1,287 @@
+"""Prepares a distribution for installation
+"""
+
+import logging
+import os
+
+from pip._vendor import requests
+
+from pip._internal.distributions import (
+    make_distribution_for_install_requirement,
+)
+from pip._internal.distributions.installed import InstalledDistribution
+from pip._internal.download import (
+    is_dir_url, is_file_url, is_vcs_url, unpack_url, url_to_path,
+)
+from pip._internal.exceptions import (
+    DirectoryUrlHashUnsupported, HashUnpinned, InstallationError,
+    PreviousBuildDirError, VcsHashUnsupported,
+)
+from pip._internal.utils.compat import expanduser
+from pip._internal.utils.hashes import MissingHashes
+from pip._internal.utils.logging import indent_log
+from pip._internal.utils.misc import display_path, normalize_path
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import Optional
+
+    from pip._internal.distributions import AbstractDistribution
+    from pip._internal.download import PipSession
+    from pip._internal.index import PackageFinder
+    from pip._internal.req.req_install import InstallRequirement
+    from pip._internal.req.req_tracker import RequirementTracker
+
+logger = logging.getLogger(__name__)
+
+
+class RequirementPreparer(object):
+    """Prepares a Requirement
+    """
+
+    def __init__(
+        self,
+        build_dir,  # type: str
+        download_dir,  # type: Optional[str]
+        src_dir,  # type: str
+        wheel_download_dir,  # type: Optional[str]
+        progress_bar,  # type: str
+        build_isolation,  # type: bool
+        req_tracker  # type: RequirementTracker
+    ):
+        # type: (...) -> None
+        super(RequirementPreparer, self).__init__()
+
+        self.src_dir = src_dir
+        self.build_dir = build_dir
+        self.req_tracker = req_tracker
+
+        # Where still packed archives should be written to. If None, they are
+        # not saved, and are deleted immediately after unpacking.
+        self.download_dir = download_dir
+
+        # Where still-packed .whl files should be written to. If None, they are
+        # written to the download_dir parameter. Separate to download_dir to
+        # permit only keeping wheel archives for pip wheel.
+        if wheel_download_dir:
+            wheel_download_dir = normalize_path(wheel_download_dir)
+        self.wheel_download_dir = wheel_download_dir
+
+        # NOTE
+        # download_dir and wheel_download_dir overlap semantically and may
+        # be combined if we're willing to have non-wheel archives present in
+        # the wheelhouse output by 'pip wheel'.
+
+        self.progress_bar = progress_bar
+
+        # Is build isolation allowed?
+        self.build_isolation = build_isolation
+
+    @property
+    def _download_should_save(self):
+        # type: () -> bool
+        # TODO: Modify to reduce indentation needed
+        if self.download_dir:
+            self.download_dir = expanduser(self.download_dir)
+            if os.path.exists(self.download_dir):
+                return True
+            else:
+                logger.critical('Could not find download directory')
+                raise InstallationError(
+                    "Could not find or access download directory '%s'"
+                    % display_path(self.download_dir))
+        return False
+
+    def prepare_linked_requirement(
+        self,
+        req,  # type: InstallRequirement
+        session,  # type: PipSession
+        finder,  # type: PackageFinder
+        upgrade_allowed,  # type: bool
+        require_hashes  # type: bool
+    ):
+        # type: (...) -> AbstractDistribution
+        """Prepare a requirement that would be obtained from req.link
+        """
+        # TODO: Breakup into smaller functions
+        if req.link and req.link.scheme == 'file':
+            path = url_to_path(req.link.url)
+            logger.info('Processing %s', display_path(path))
+        else:
+            logger.info('Collecting %s', req)
+
+        with indent_log():
+            # @@ if filesystem packages are not marked
+            # editable in a req, a non deterministic error
+            # occurs when the script attempts to unpack the
+            # build directory
+            req.ensure_has_source_dir(self.build_dir)
+            # If a checkout exists, it's unwise to keep going.  version
+            # inconsistencies are logged later, but do not fail the
+            # installation.
+            # FIXME: this won't upgrade when there's an existing
+            # package unpacked in `req.source_dir`
+            # package unpacked in `req.source_dir`
+            if os.path.exists(os.path.join(req.source_dir, 'setup.py')):
+                raise PreviousBuildDirError(
+                    "pip can't proceed with requirements '%s' due to a"
+                    " pre-existing build directory (%s). This is "
+                    "likely due to a previous installation that failed"
+                    ". pip is being responsible and not assuming it "
+                    "can delete this. Please delete it and try again."
+                    % (req, req.source_dir)
+                )
+            req.populate_link(finder, upgrade_allowed, require_hashes)
+
+            # We can't hit this spot and have populate_link return None.
+            # req.satisfied_by is None here (because we're
+            # guarded) and upgrade has no impact except when satisfied_by
+            # is not None.
+            # Then inside find_requirement existing_applicable -> False
+            # If no new versions are found, DistributionNotFound is raised,
+            # otherwise a result is guaranteed.
+            assert req.link
+            link = req.link
+
+            # Now that we have the real link, we can tell what kind of
+            # requirements we have and raise some more informative errors
+            # than otherwise. (For example, we can raise VcsHashUnsupported
+            # for a VCS URL rather than HashMissing.)
+            if require_hashes:
+                # We could check these first 2 conditions inside
+                # unpack_url and save repetition of conditions, but then
+                # we would report less-useful error messages for
+                # unhashable requirements, complaining that there's no
+                # hash provided.
+                if is_vcs_url(link):
+                    raise VcsHashUnsupported()
+                elif is_file_url(link) and is_dir_url(link):
+                    raise DirectoryUrlHashUnsupported()
+                if not req.original_link and not req.is_pinned:
+                    # Unpinned packages are asking for trouble when a new
+                    # version is uploaded. This isn't a security check, but
+                    # it saves users a surprising hash mismatch in the
+                    # future.
+                    #
+                    # file:/// URLs aren't pinnable, so don't complain
+                    # about them not being pinned.
+                    raise HashUnpinned()
+
+            hashes = req.hashes(trust_internet=not require_hashes)
+            if require_hashes and not hashes:
+                # Known-good hashes are missing for this requirement, so
+                # shim it with a facade object that will provoke hash
+                # computation and then raise a HashMissing exception
+                # showing the user what the hash should be.
+                hashes = MissingHashes()
+
+            try:
+                download_dir = self.download_dir
+                # We always delete unpacked sdists after pip ran.
+                autodelete_unpacked = True
+                if req.link.is_wheel and self.wheel_download_dir:
+                    # when doing 'pip wheel` we download wheels to a
+                    # dedicated dir.
+                    download_dir = self.wheel_download_dir
+                if req.link.is_wheel:
+                    if download_dir:
+                        # When downloading, we only unpack wheels to get
+                        # metadata.
+                        autodelete_unpacked = True
+                    else:
+                        # When installing a wheel, we use the unpacked
+                        # wheel.
+                        autodelete_unpacked = False
+                unpack_url(
+                    req.link, req.source_dir,
+                    download_dir, autodelete_unpacked,
+                    session=session, hashes=hashes,
+                    progress_bar=self.progress_bar
+                )
+            except requests.HTTPError as exc:
+                logger.critical(
+                    'Could not install requirement %s because of error %s',
+                    req,
+                    exc,
+                )
+                raise InstallationError(
+                    'Could not install requirement %s because of HTTP '
+                    'error %s for URL %s' %
+                    (req, exc, req.link)
+                )
+            abstract_dist = make_distribution_for_install_requirement(req)
+            with self.req_tracker.track(req):
+                abstract_dist.prepare_distribution_metadata(
+                    finder, self.build_isolation,
+                )
+            if self._download_should_save:
+                # Make a .zip of the source_dir we already created.
+                if not req.link.is_artifact:
+                    req.archive(self.download_dir)
+        return abstract_dist
+
+    def prepare_editable_requirement(
+        self,
+        req,  # type: InstallRequirement
+        require_hashes,  # type: bool
+        use_user_site,  # type: bool
+        finder  # type: PackageFinder
+    ):
+        # type: (...) -> AbstractDistribution
+        """Prepare an editable requirement
+        """
+        assert req.editable, "cannot prepare a non-editable req as editable"
+
+        logger.info('Obtaining %s', req)
+
+        with indent_log():
+            if require_hashes:
+                raise InstallationError(
+                    'The editable requirement %s cannot be installed when '
+                    'requiring hashes, because there is no single file to '
+                    'hash.' % req
+                )
+            req.ensure_has_source_dir(self.src_dir)
+            req.update_editable(not self._download_should_save)
+
+            abstract_dist = make_distribution_for_install_requirement(req)
+            with self.req_tracker.track(req):
+                abstract_dist.prepare_distribution_metadata(
+                    finder, self.build_isolation,
+                )
+
+            if self._download_should_save:
+                req.archive(self.download_dir)
+            req.check_if_exists(use_user_site)
+
+        return abstract_dist
+
+    def prepare_installed_requirement(
+        self,
+        req,  # type: InstallRequirement
+        require_hashes,  # type: bool
+        skip_reason  # type: str
+    ):
+        # type: (...) -> AbstractDistribution
+        """Prepare an already-installed requirement
+        """
+        assert req.satisfied_by, "req should have been satisfied but isn't"
+        assert skip_reason is not None, (
+            "did not get skip reason skipped but req.satisfied_by "
+            "is set to %r" % (req.satisfied_by,)
+        )
+        logger.info(
+            'Requirement %s: %s (%s)',
+            skip_reason, req, req.satisfied_by.version
+        )
+        with indent_log():
+            if require_hashes:
+                logger.debug(
+                    'Since it is already installed, we are trusting this '
+                    'package without checking its hash. To ensure a '
+                    'completely repeatable environment, install into an '
+                    'empty virtualenv.'
+                )
+            abstract_dist = InstalledDistribution(req)
+
+        return abstract_dist