Created starter files for the project.

venv/Lib/site-packages/pip/_internal/operations/build/metadata.py

@@ -0,0 +1,37 @@
+"""Metadata generation logic for source distributions.
+"""
+
+import os
+
+from pip._internal.utils.subprocess import runner_with_spinner_message
+from pip._internal.utils.temp_dir import TempDirectory
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from pip._internal.build_env import BuildEnvironment
+    from pip._vendor.pep517.wrappers import Pep517HookCaller
+
+
+def generate_metadata(build_env, backend):
+    # type: (BuildEnvironment, Pep517HookCaller) -> str
+    """Generate metadata using mechanisms described in PEP 517.
+
+    Returns the generated metadata directory.
+    """
+    metadata_tmpdir = TempDirectory(
+        kind="modern-metadata", globally_managed=True
+    )
+
+    metadata_dir = metadata_tmpdir.path
+
+    with build_env:
+        # Note that Pep517HookCaller implements a fallback for
+        # prepare_metadata_for_build_wheel, so we don't have to
+        # consider the possibility that this hook doesn't exist.
+        runner = runner_with_spinner_message("Preparing wheel metadata")
+        with backend.subprocess_runner(runner):
+            distinfo_dir = backend.prepare_metadata_for_build_wheel(
+                metadata_dir
+            )
+
+    return os.path.join(metadata_dir, distinfo_dir)

venv/Lib/site-packages/pip/_internal/operations/build/metadata_legacy.py

@@ -0,0 +1,77 @@
+"""Metadata generation logic for legacy source distributions.
+"""
+
+import logging
+import os
+
+from pip._internal.exceptions import InstallationError
+from pip._internal.utils.setuptools_build import make_setuptools_egg_info_args
+from pip._internal.utils.subprocess import call_subprocess
+from pip._internal.utils.temp_dir import TempDirectory
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from pip._internal.build_env import BuildEnvironment
+
+logger = logging.getLogger(__name__)
+
+
+def _find_egg_info(directory):
+    # type: (str) -> str
+    """Find an .egg-info subdirectory in `directory`.
+    """
+    filenames = [
+        f for f in os.listdir(directory) if f.endswith(".egg-info")
+    ]
+
+    if not filenames:
+        raise InstallationError(
+            "No .egg-info directory found in {}".format(directory)
+        )
+
+    if len(filenames) > 1:
+        raise InstallationError(
+            "More than one .egg-info directory found in {}".format(
+                directory
+            )
+        )
+
+    return os.path.join(directory, filenames[0])
+
+
+def generate_metadata(
+    build_env,  # type: BuildEnvironment
+    setup_py_path,  # type: str
+    source_dir,  # type: str
+    isolated,  # type: bool
+    details,  # type: str
+):
+    # type: (...) -> str
+    """Generate metadata using setup.py-based defacto mechanisms.
+
+    Returns the generated metadata directory.
+    """
+    logger.debug(
+        'Running setup.py (path:%s) egg_info for package %s',
+        setup_py_path, details,
+    )
+
+    egg_info_dir = TempDirectory(
+        kind="pip-egg-info", globally_managed=True
+    ).path
+
+    args = make_setuptools_egg_info_args(
+        setup_py_path,
+        egg_info_dir=egg_info_dir,
+        no_user_config=isolated,
+    )
+
+    with build_env:
+        call_subprocess(
+            args,
+            cwd=source_dir,
+            command_desc='python setup.py egg_info',
+        )
+
+    # Return the .egg-info directory.
+    return _find_egg_info(egg_info_dir)

venv/Lib/site-packages/pip/_internal/operations/build/wheel.py

@@ -0,0 +1,46 @@
+import logging
+import os
+
+from pip._internal.utils.subprocess import runner_with_spinner_message
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional
+    from pip._vendor.pep517.wrappers import Pep517HookCaller
+
+logger = logging.getLogger(__name__)
+
+
+def build_wheel_pep517(
+    name,  # type: str
+    backend,  # type: Pep517HookCaller
+    metadata_directory,  # type: str
+    build_options,  # type: List[str]
+    tempd,  # type: str
+):
+    # type: (...) -> Optional[str]
+    """Build one InstallRequirement using the PEP 517 build process.
+
+    Returns path to wheel if successfully built. Otherwise, returns None.
+    """
+    assert metadata_directory is not None
+    if build_options:
+        # PEP 517 does not support --build-options
+        logger.error('Cannot build wheel for %s using PEP 517 when '
+                     '--build-option is present', name)
+        return None
+    try:
+        logger.debug('Destination directory: %s', tempd)
+
+        runner = runner_with_spinner_message(
+            'Building wheel for {} (PEP 517)'.format(name)
+        )
+        with backend.subprocess_runner(runner):
+            wheel_name = backend.build_wheel(
+                tempd,
+                metadata_directory=metadata_directory,
+            )
+    except Exception:
+        logger.error('Failed building wheel for %s', name)
+        return None
+    return os.path.join(tempd, wheel_name)

venv/Lib/site-packages/pip/_internal/operations/build/wheel_legacy.py

@@ -0,0 +1,115 @@
+import logging
+import os.path
+
+from pip._internal.cli.spinners import open_spinner
+from pip._internal.utils.setuptools_build import (
+    make_setuptools_bdist_wheel_args,
+)
+from pip._internal.utils.subprocess import (
+    LOG_DIVIDER,
+    call_subprocess,
+    format_command_args,
+)
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional, Text
+
+logger = logging.getLogger(__name__)
+
+
+def format_command_result(
+    command_args,  # type: List[str]
+    command_output,  # type: Text
+):
+    # type: (...) -> str
+    """Format command information for logging."""
+    command_desc = format_command_args(command_args)
+    text = 'Command arguments: {}\n'.format(command_desc)
+
+    if not command_output:
+        text += 'Command output: None'
+    elif logger.getEffectiveLevel() > logging.DEBUG:
+        text += 'Command output: [use --verbose to show]'
+    else:
+        if not command_output.endswith('\n'):
+            command_output += '\n'
+        text += 'Command output:\n{}{}'.format(command_output, LOG_DIVIDER)
+
+    return text
+
+
+def get_legacy_build_wheel_path(
+    names,  # type: List[str]
+    temp_dir,  # type: str
+    name,  # type: str
+    command_args,  # type: List[str]
+    command_output,  # type: Text
+):
+    # type: (...) -> Optional[str]
+    """Return the path to the wheel in the temporary build directory."""
+    # Sort for determinism.
+    names = sorted(names)
+    if not names:
+        msg = (
+            'Legacy build of wheel for {!r} created no files.\n'
+        ).format(name)
+        msg += format_command_result(command_args, command_output)
+        logger.warning(msg)
+        return None
+
+    if len(names) > 1:
+        msg = (
+            'Legacy build of wheel for {!r} created more than one file.\n'
+            'Filenames (choosing first): {}\n'
+        ).format(name, names)
+        msg += format_command_result(command_args, command_output)
+        logger.warning(msg)
+
+    return os.path.join(temp_dir, names[0])
+
+
+def build_wheel_legacy(
+    name,  # type: str
+    setup_py_path,  # type: str
+    source_dir,  # type: str
+    global_options,  # type: List[str]
+    build_options,  # type: List[str]
+    tempd,  # type: str
+):
+    # type: (...) -> Optional[str]
+    """Build one unpacked package using the "legacy" build process.
+
+    Returns path to wheel if successfully built. Otherwise, returns None.
+    """
+    wheel_args = make_setuptools_bdist_wheel_args(
+        setup_py_path,
+        global_options=global_options,
+        build_options=build_options,
+        destination_dir=tempd,
+    )
+
+    spin_message = 'Building wheel for {} (setup.py)'.format(name)
+    with open_spinner(spin_message) as spinner:
+        logger.debug('Destination directory: %s', tempd)
+
+        try:
+            output = call_subprocess(
+                wheel_args,
+                cwd=source_dir,
+                spinner=spinner,
+            )
+        except Exception:
+            spinner.finish("error")
+            logger.error('Failed building wheel for %s', name)
+            return None
+
+        names = os.listdir(tempd)
+        wheel_path = get_legacy_build_wheel_path(
+            names=names,
+            temp_dir=tempd,
+            name=name,
+            command_args=wheel_args,
+            command_output=output,
+        )
+        return wheel_path

venv/Lib/site-packages/pip/_internal/operations/check.py

@@ -0,0 +1,158 @@
+"""Validation of dependencies of packages
+"""
+
+import logging
+from collections import namedtuple
+
+from pip._vendor.packaging.utils import canonicalize_name
+from pip._vendor.pkg_resources import RequirementParseError
+
+from pip._internal.distributions import (
+    make_distribution_for_install_requirement,
+)
+from pip._internal.utils.misc import get_installed_distributions
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+logger = logging.getLogger(__name__)
+
+if MYPY_CHECK_RUNNING:
+    from pip._internal.req.req_install import InstallRequirement
+    from typing import (
+        Any, Callable, Dict, Optional, Set, Tuple, List
+    )
+
+    # Shorthands
+    PackageSet = Dict[str, 'PackageDetails']
+    Missing = Tuple[str, Any]
+    Conflicting = Tuple[str, str, Any]
+
+    MissingDict = Dict[str, List[Missing]]
+    ConflictingDict = Dict[str, List[Conflicting]]
+    CheckResult = Tuple[MissingDict, ConflictingDict]
+    ConflictDetails = Tuple[PackageSet, CheckResult]
+
+PackageDetails = namedtuple('PackageDetails', ['version', 'requires'])
+
+
+def create_package_set_from_installed(**kwargs):
+    # type: (**Any) -> Tuple[PackageSet, bool]
+    """Converts a list of distributions into a PackageSet.
+    """
+    # Default to using all packages installed on the system
+    if kwargs == {}:
+        kwargs = {"local_only": False, "skip": ()}
+
+    package_set = {}
+    problems = False
+    for dist in get_installed_distributions(**kwargs):
+        name = canonicalize_name(dist.project_name)
+        try:
+            package_set[name] = PackageDetails(dist.version, dist.requires())
+        except RequirementParseError as e:
+            # Don't crash on broken metadata
+            logger.warning("Error parsing requirements for %s: %s", name, e)
+            problems = True
+    return package_set, problems
+
+
+def check_package_set(package_set, should_ignore=None):
+    # type: (PackageSet, Optional[Callable[[str], bool]]) -> CheckResult
+    """Check if a package set is consistent
+
+    If should_ignore is passed, it should be a callable that takes a
+    package name and returns a boolean.
+    """
+
+    missing = {}
+    conflicting = {}
+
+    for package_name in package_set:
+        # Info about dependencies of package_name
+        missing_deps = set()  # type: Set[Missing]
+        conflicting_deps = set()  # type: Set[Conflicting]
+
+        if should_ignore and should_ignore(package_name):
+            continue
+
+        for req in package_set[package_name].requires:
+            name = canonicalize_name(req.project_name)  # type: str
+
+            # Check if it's missing
+            if name not in package_set:
+                missed = True
+                if req.marker is not None:
+                    missed = req.marker.evaluate()
+                if missed:
+                    missing_deps.add((name, req))
+                continue
+
+            # Check if there's a conflict
+            version = package_set[name].version  # type: str
+            if not req.specifier.contains(version, prereleases=True):
+                conflicting_deps.add((name, version, req))
+
+        if missing_deps:
+            missing[package_name] = sorted(missing_deps, key=str)
+        if conflicting_deps:
+            conflicting[package_name] = sorted(conflicting_deps, key=str)
+
+    return missing, conflicting
+
+
+def check_install_conflicts(to_install):
+    # type: (List[InstallRequirement]) -> ConflictDetails
+    """For checking if the dependency graph would be consistent after \
+    installing given requirements
+    """
+    # Start from the current state
+    package_set, _ = create_package_set_from_installed()
+    # Install packages
+    would_be_installed = _simulate_installation_of(to_install, package_set)
+
+    # Only warn about directly-dependent packages; create a whitelist of them
+    whitelist = _create_whitelist(would_be_installed, package_set)
+
+    return (
+        package_set,
+        check_package_set(
+            package_set, should_ignore=lambda name: name not in whitelist
+        )
+    )
+
+
+def _simulate_installation_of(to_install, package_set):
+    # type: (List[InstallRequirement], PackageSet) -> Set[str]
+    """Computes the version of packages after installing to_install.
+    """
+
+    # Keep track of packages that were installed
+    installed = set()
+
+    # Modify it as installing requirement_set would (assuming no errors)
+    for inst_req in to_install:
+        abstract_dist = make_distribution_for_install_requirement(inst_req)
+        dist = abstract_dist.get_pkg_resources_distribution()
+
+        assert dist is not None
+        name = canonicalize_name(dist.key)
+        package_set[name] = PackageDetails(dist.version, dist.requires())
+
+        installed.add(name)
+
+    return installed
+
+
+def _create_whitelist(would_be_installed, package_set):
+    # type: (Set[str], PackageSet) -> Set[str]
+    packages_affected = set(would_be_installed)
+
+    for package_name in package_set:
+        if package_name in packages_affected:
+            continue
+
+        for req in package_set[package_name].requires:
+            if canonicalize_name(req.name) in packages_affected:
+                packages_affected.add(package_name)
+                break
+
+    return packages_affected

venv/Lib/site-packages/pip/_internal/operations/freeze.py

@@ -0,0 +1,272 @@
+from __future__ import absolute_import
+
+import collections
+import logging
+import os
+
+from pip._vendor import six
+from pip._vendor.packaging.utils import canonicalize_name
+from pip._vendor.pkg_resources import RequirementParseError
+
+from pip._internal.exceptions import BadCommand, InstallationError
+from pip._internal.req.constructors import (
+    install_req_from_editable,
+    install_req_from_line,
+)
+from pip._internal.req.req_file import COMMENT_RE
+from pip._internal.utils.direct_url_helpers import (
+    direct_url_as_pep440_direct_reference,
+    dist_get_direct_url,
+)
+from pip._internal.utils.misc import (
+    dist_is_editable,
+    get_installed_distributions,
+)
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import (
+        Iterator, Optional, List, Container, Set, Dict, Tuple, Iterable, Union
+    )
+    from pip._internal.cache import WheelCache
+    from pip._vendor.pkg_resources import (
+        Distribution, Requirement
+    )
+
+    RequirementInfo = Tuple[Optional[Union[str, Requirement]], bool, List[str]]
+
+
+logger = logging.getLogger(__name__)
+
+
+def freeze(
+    requirement=None,  # type: Optional[List[str]]
+    find_links=None,  # type: Optional[List[str]]
+    local_only=False,  # type: bool
+    user_only=False,  # type: bool
+    paths=None,  # type: Optional[List[str]]
+    isolated=False,  # type: bool
+    wheel_cache=None,  # type: Optional[WheelCache]
+    exclude_editable=False,  # type: bool
+    skip=()  # type: Container[str]
+):
+    # type: (...) -> Iterator[str]
+    find_links = find_links or []
+
+    for link in find_links:
+        yield '-f {}'.format(link)
+    installations = {}  # type: Dict[str, FrozenRequirement]
+
+    for dist in get_installed_distributions(
+            local_only=local_only,
+            skip=(),
+            user_only=user_only,
+            paths=paths
+    ):
+        try:
+            req = FrozenRequirement.from_dist(dist)
+        except RequirementParseError as exc:
+            # We include dist rather than dist.project_name because the
+            # dist string includes more information, like the version and
+            # location. We also include the exception message to aid
+            # troubleshooting.
+            logger.warning(
+                'Could not generate requirement for distribution %r: %s',
+                dist, exc
+            )
+            continue
+        if exclude_editable and req.editable:
+            continue
+        installations[req.canonical_name] = req
+
+    if requirement:
+        # the options that don't get turned into an InstallRequirement
+        # should only be emitted once, even if the same option is in multiple
+        # requirements files, so we need to keep track of what has been emitted
+        # so that we don't emit it again if it's seen again
+        emitted_options = set()  # type: Set[str]
+        # keep track of which files a requirement is in so that we can
+        # give an accurate warning if a requirement appears multiple times.
+        req_files = collections.defaultdict(list)  # type: Dict[str, List[str]]
+        for req_file_path in requirement:
+            with open(req_file_path) as req_file:
+                for line in req_file:
+                    if (not line.strip() or
+                            line.strip().startswith('#') or
+                            line.startswith((
+                                '-r', '--requirement',
+                                '-f', '--find-links',
+                                '-i', '--index-url',
+                                '--pre',
+                                '--trusted-host',
+                                '--process-dependency-links',
+                                '--extra-index-url',
+                                '--use-feature'))):
+                        line = line.rstrip()
+                        if line not in emitted_options:
+                            emitted_options.add(line)
+                            yield line
+                        continue
+
+                    if line.startswith('-e') or line.startswith('--editable'):
+                        if line.startswith('-e'):
+                            line = line[2:].strip()
+                        else:
+                            line = line[len('--editable'):].strip().lstrip('=')
+                        line_req = install_req_from_editable(
+                            line,
+                            isolated=isolated,
+                        )
+                    else:
+                        line_req = install_req_from_line(
+                            COMMENT_RE.sub('', line).strip(),
+                            isolated=isolated,
+                        )
+
+                    if not line_req.name:
+                        logger.info(
+                            "Skipping line in requirement file [%s] because "
+                            "it's not clear what it would install: %s",
+                            req_file_path, line.strip(),
+                        )
+                        logger.info(
+                            "  (add #egg=PackageName to the URL to avoid"
+                            " this warning)"
+                        )
+                    else:
+                        line_req_canonical_name = canonicalize_name(
+                            line_req.name)
+                        if line_req_canonical_name not in installations:
+                            # either it's not installed, or it is installed
+                            # but has been processed already
+                            if not req_files[line_req.name]:
+                                logger.warning(
+                                    "Requirement file [%s] contains %s, but "
+                                    "package %r is not installed",
+                                    req_file_path,
+                                    COMMENT_RE.sub('', line).strip(),
+                                    line_req.name
+                                )
+                            else:
+                                req_files[line_req.name].append(req_file_path)
+                        else:
+                            yield str(installations[
+                                line_req_canonical_name]).rstrip()
+                            del installations[line_req_canonical_name]
+                            req_files[line_req.name].append(req_file_path)
+
+        # Warn about requirements that were included multiple times (in a
+        # single requirements file or in different requirements files).
+        for name, files in six.iteritems(req_files):
+            if len(files) > 1:
+                logger.warning("Requirement %s included multiple times [%s]",
+                               name, ', '.join(sorted(set(files))))
+
+        yield(
+            '## The following requirements were added by '
+            'pip freeze:'
+        )
+    for installation in sorted(
+            installations.values(), key=lambda x: x.name.lower()):
+        if installation.canonical_name not in skip:
+            yield str(installation).rstrip()
+
+
+def get_requirement_info(dist):
+    # type: (Distribution) -> RequirementInfo
+    """
+    Compute and return values (req, editable, comments) for use in
+    FrozenRequirement.from_dist().
+    """
+    if not dist_is_editable(dist):
+        return (None, False, [])
+
+    location = os.path.normcase(os.path.abspath(dist.location))
+
+    from pip._internal.vcs import vcs, RemoteNotFoundError
+    vcs_backend = vcs.get_backend_for_dir(location)
+
+    if vcs_backend is None:
+        req = dist.as_requirement()
+        logger.debug(
+            'No VCS found for editable requirement "%s" in: %r', req,
+            location,
+        )
+        comments = [
+            '# Editable install with no version control ({})'.format(req)
+        ]
+        return (location, True, comments)
+
+    try:
+        req = vcs_backend.get_src_requirement(location, dist.project_name)
+    except RemoteNotFoundError:
+        req = dist.as_requirement()
+        comments = [
+            '# Editable {} install with no remote ({})'.format(
+                type(vcs_backend).__name__, req,
+            )
+        ]
+        return (location, True, comments)
+
+    except BadCommand:
+        logger.warning(
+            'cannot determine version of editable source in %s '
+            '(%s command not found in path)',
+            location,
+            vcs_backend.name,
+        )
+        return (None, True, [])
+
+    except InstallationError as exc:
+        logger.warning(
+            "Error when trying to get requirement for VCS system %s, "
+            "falling back to uneditable format", exc
+        )
+    else:
+        if req is not None:
+            return (req, True, [])
+
+    logger.warning(
+        'Could not determine repository location of %s', location
+    )
+    comments = ['## !! Could not determine repository location']
+
+    return (None, False, comments)
+
+
+class FrozenRequirement(object):
+    def __init__(self, name, req, editable, comments=()):
+        # type: (str, Union[str, Requirement], bool, Iterable[str]) -> None
+        self.name = name
+        self.canonical_name = canonicalize_name(name)
+        self.req = req
+        self.editable = editable
+        self.comments = comments
+
+    @classmethod
+    def from_dist(cls, dist):
+        # type: (Distribution) -> FrozenRequirement
+        # TODO `get_requirement_info` is taking care of editable requirements.
+        # TODO This should be refactored when we will add detection of
+        #      editable that provide .dist-info metadata.
+        req, editable, comments = get_requirement_info(dist)
+        if req is None and not editable:
+            # if PEP 610 metadata is present, attempt to use it
+            direct_url = dist_get_direct_url(dist)
+            if direct_url:
+                req = direct_url_as_pep440_direct_reference(
+                    direct_url, dist.project_name
+                )
+                comments = []
+        if req is None:
+            # name==version requirement
+            req = dist.as_requirement()
+
+        return cls(dist.project_name, req, editable, comments=comments)
+
+    def __str__(self):
+        # type: () -> str
+        req = self.req
+        if self.editable:
+            req = '-e {}'.format(req)
+        return '\n'.join(list(self.comments) + [str(req)]) + '\n'

venv/Lib/site-packages/pip/_internal/operations/install/__init__.py

@@ -0,0 +1,2 @@
+"""For modules related to installing packages.
+"""

venv/Lib/site-packages/pip/_internal/operations/install/editable_legacy.py

@@ -0,0 +1,52 @@
+"""Legacy editable installation process, i.e. `setup.py develop`.
+"""
+import logging
+
+from pip._internal.utils.logging import indent_log
+from pip._internal.utils.setuptools_build import make_setuptools_develop_args
+from pip._internal.utils.subprocess import call_subprocess
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional, Sequence
+
+    from pip._internal.build_env import BuildEnvironment
+
+
+logger = logging.getLogger(__name__)
+
+
+def install_editable(
+    install_options,  # type: List[str]
+    global_options,  # type: Sequence[str]
+    prefix,  # type: Optional[str]
+    home,  # type: Optional[str]
+    use_user_site,  # type: bool
+    name,  # type: str
+    setup_py_path,  # type: str
+    isolated,  # type: bool
+    build_env,  # type: BuildEnvironment
+    unpacked_source_directory,  # type: str
+):
+    # type: (...) -> None
+    """Install a package in editable mode. Most arguments are pass-through
+    to setuptools.
+    """
+    logger.info('Running setup.py develop for %s', name)
+
+    args = make_setuptools_develop_args(
+        setup_py_path,
+        global_options=global_options,
+        install_options=install_options,
+        no_user_config=isolated,
+        prefix=prefix,
+        home=home,
+        use_user_site=use_user_site,
+    )
+
+    with indent_log():
+        with build_env:
+            call_subprocess(
+                args,
+                cwd=unpacked_source_directory,
+            )

venv/Lib/site-packages/pip/_internal/operations/install/legacy.py

@@ -0,0 +1,130 @@
+"""Legacy installation process, i.e. `setup.py install`.
+"""
+
+import logging
+import os
+import sys
+from distutils.util import change_root
+
+from pip._internal.exceptions import InstallationError
+from pip._internal.utils.logging import indent_log
+from pip._internal.utils.misc import ensure_dir
+from pip._internal.utils.setuptools_build import make_setuptools_install_args
+from pip._internal.utils.subprocess import runner_with_spinner_message
+from pip._internal.utils.temp_dir import TempDirectory
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+
+if MYPY_CHECK_RUNNING:
+    from typing import List, Optional, Sequence
+
+    from pip._internal.build_env import BuildEnvironment
+    from pip._internal.models.scheme import Scheme
+
+
+logger = logging.getLogger(__name__)
+
+
+class LegacyInstallFailure(Exception):
+    def __init__(self):
+        # type: () -> None
+        self.parent = sys.exc_info()
+
+
+def install(
+    install_options,  # type: List[str]
+    global_options,  # type: Sequence[str]
+    root,  # type: Optional[str]
+    home,  # type: Optional[str]
+    prefix,  # type: Optional[str]
+    use_user_site,  # type: bool
+    pycompile,  # type: bool
+    scheme,  # type: Scheme
+    setup_py_path,  # type: str
+    isolated,  # type: bool
+    req_name,  # type: str
+    build_env,  # type: BuildEnvironment
+    unpacked_source_directory,  # type: str
+    req_description,  # type: str
+):
+    # type: (...) -> bool
+
+    header_dir = scheme.headers
+
+    with TempDirectory(kind="record") as temp_dir:
+        try:
+            record_filename = os.path.join(temp_dir.path, 'install-record.txt')
+            install_args = make_setuptools_install_args(
+                setup_py_path,
+                global_options=global_options,
+                install_options=install_options,
+                record_filename=record_filename,
+                root=root,
+                prefix=prefix,
+                header_dir=header_dir,
+                home=home,
+                use_user_site=use_user_site,
+                no_user_config=isolated,
+                pycompile=pycompile,
+            )
+
+            runner = runner_with_spinner_message(
+                "Running setup.py install for {}".format(req_name)
+            )
+            with indent_log(), build_env:
+                runner(
+                    cmd=install_args,
+                    cwd=unpacked_source_directory,
+                )
+
+            if not os.path.exists(record_filename):
+                logger.debug('Record file %s not found', record_filename)
+                # Signal to the caller that we didn't install the new package
+                return False
+
+        except Exception:
+            # Signal to the caller that we didn't install the new package
+            raise LegacyInstallFailure
+
+        # At this point, we have successfully installed the requirement.
+
+        # We intentionally do not use any encoding to read the file because
+        # setuptools writes the file using distutils.file_util.write_file,
+        # which does not specify an encoding.
+        with open(record_filename) as f:
+            record_lines = f.read().splitlines()
+
+    def prepend_root(path):
+        # type: (str) -> str
+        if root is None or not os.path.isabs(path):
+            return path
+        else:
+            return change_root(root, path)
+
+    for line in record_lines:
+        directory = os.path.dirname(line)
+        if directory.endswith('.egg-info'):
+            egg_info_dir = prepend_root(directory)
+            break
+    else:
+        message = (
+            "{} did not indicate that it installed an "
+            ".egg-info directory. Only setup.py projects "
+            "generating .egg-info directories are supported."
+        ).format(req_description)
+        raise InstallationError(message)
+
+    new_lines = []
+    for line in record_lines:
+        filename = line.strip()
+        if os.path.isdir(filename):
+            filename += os.path.sep
+        new_lines.append(
+            os.path.relpath(prepend_root(filename), egg_info_dir)
+        )
+    new_lines.sort()
+    ensure_dir(egg_info_dir)
+    inst_files_path = os.path.join(egg_info_dir, 'installed-files.txt')
+    with open(inst_files_path, 'w') as f:
+        f.write('\n'.join(new_lines) + '\n')
+
+    return True

venv/Lib/site-packages/pip/_internal/operations/install/wheel.py

@@ -0,0 +1,861 @@
+"""Support for installing and building the "wheel" binary package format.
+"""
+
+from __future__ import absolute_import
+
+import collections
+import compileall
+import contextlib
+import csv
+import importlib
+import logging
+import os.path
+import re
+import shutil
+import sys
+import warnings
+from base64 import urlsafe_b64encode
+from itertools import chain, starmap
+from zipfile import ZipFile
+
+from pip._vendor import pkg_resources
+from pip._vendor.distlib.scripts import ScriptMaker
+from pip._vendor.distlib.util import get_export_entry
+from pip._vendor.six import (
+    PY2,
+    ensure_str,
+    ensure_text,
+    itervalues,
+    reraise,
+    text_type,
+)
+from pip._vendor.six.moves import filterfalse, map
+
+from pip._internal.exceptions import InstallationError
+from pip._internal.locations import get_major_minor_version
+from pip._internal.models.direct_url import DIRECT_URL_METADATA_NAME, DirectUrl
+from pip._internal.models.scheme import SCHEME_KEYS
+from pip._internal.utils.filesystem import adjacent_tmp_file, replace
+from pip._internal.utils.misc import (
+    captured_stdout,
+    ensure_dir,
+    hash_file,
+    partition,
+)
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+from pip._internal.utils.unpacking import (
+    current_umask,
+    is_within_directory,
+    set_extracted_file_to_default_mode_plus_executable,
+    zip_item_is_executable,
+)
+from pip._internal.utils.wheel import (
+    parse_wheel,
+    pkg_resources_distribution_for_wheel,
+)
+
+# Use the custom cast function at runtime to make cast work,
+# and import typing.cast when performing pre-commit and type
+# checks
+if not MYPY_CHECK_RUNNING:
+    from pip._internal.utils.typing import cast
+else:
+    from email.message import Message
+    from typing import (
+        Any,
+        Callable,
+        Dict,
+        IO,
+        Iterable,
+        Iterator,
+        List,
+        NewType,
+        Optional,
+        Protocol,
+        Sequence,
+        Set,
+        Tuple,
+        Union,
+        cast,
+    )
+    from zipfile import ZipInfo
+
+    from pip._vendor.pkg_resources import Distribution
+
+    from pip._internal.models.scheme import Scheme
+    from pip._internal.utils.filesystem import NamedTemporaryFileResult
+
+    RecordPath = NewType('RecordPath', text_type)
+    InstalledCSVRow = Tuple[RecordPath, str, Union[int, str]]
+
+    class File(Protocol):
+        src_record_path = None  # type: RecordPath
+        dest_path = None  # type: text_type
+        changed = None  # type: bool
+
+        def save(self):
+            # type: () -> None
+            pass
+
+
+logger = logging.getLogger(__name__)
+
+
+def rehash(path, blocksize=1 << 20):
+    # type: (text_type, int) -> Tuple[str, str]
+    """Return (encoded_digest, length) for path using hashlib.sha256()"""
+    h, length = hash_file(path, blocksize)
+    digest = 'sha256=' + urlsafe_b64encode(
+        h.digest()
+    ).decode('latin1').rstrip('=')
+    # unicode/str python2 issues
+    return (digest, str(length))  # type: ignore
+
+
+def csv_io_kwargs(mode):
+    # type: (str) -> Dict[str, Any]
+    """Return keyword arguments to properly open a CSV file
+    in the given mode.
+    """
+    if PY2:
+        return {'mode': '{}b'.format(mode)}
+    else:
+        return {'mode': mode, 'newline': '', 'encoding': 'utf-8'}
+
+
+def fix_script(path):
+    # type: (text_type) -> bool
+    """Replace #!python with #!/path/to/python
+    Return True if file was changed.
+    """
+    # XXX RECORD hashes will need to be updated
+    assert os.path.isfile(path)
+
+    with open(path, 'rb') as script:
+        firstline = script.readline()
+        if not firstline.startswith(b'#!python'):
+            return False
+        exename = sys.executable.encode(sys.getfilesystemencoding())
+        firstline = b'#!' + exename + os.linesep.encode("ascii")
+        rest = script.read()
+    with open(path, 'wb') as script:
+        script.write(firstline)
+        script.write(rest)
+    return True
+
+
+def wheel_root_is_purelib(metadata):
+    # type: (Message) -> bool
+    return metadata.get("Root-Is-Purelib", "").lower() == "true"
+
+
+def get_entrypoints(distribution):
+    # type: (Distribution) -> Tuple[Dict[str, str], Dict[str, str]]
+    # get the entry points and then the script names
+    try:
+        console = distribution.get_entry_map('console_scripts')
+        gui = distribution.get_entry_map('gui_scripts')
+    except KeyError:
+        # Our dict-based Distribution raises KeyError if entry_points.txt
+        # doesn't exist.
+        return {}, {}
+
+    def _split_ep(s):
+        # type: (pkg_resources.EntryPoint) -> Tuple[str, str]
+        """get the string representation of EntryPoint,
+        remove space and split on '='
+        """
+        split_parts = str(s).replace(" ", "").split("=")
+        return split_parts[0], split_parts[1]
+
+    # convert the EntryPoint objects into strings with module:function
+    console = dict(_split_ep(v) for v in console.values())
+    gui = dict(_split_ep(v) for v in gui.values())
+    return console, gui
+
+
+def message_about_scripts_not_on_PATH(scripts):
+    # type: (Sequence[str]) -> Optional[str]
+    """Determine if any scripts are not on PATH and format a warning.
+    Returns a warning message if one or more scripts are not on PATH,
+    otherwise None.
+    """
+    if not scripts:
+        return None
+
+    # Group scripts by the path they were installed in
+    grouped_by_dir = collections.defaultdict(set)  # type: Dict[str, Set[str]]
+    for destfile in scripts:
+        parent_dir = os.path.dirname(destfile)
+        script_name = os.path.basename(destfile)
+        grouped_by_dir[parent_dir].add(script_name)
+
+    # We don't want to warn for directories that are on PATH.
+    not_warn_dirs = [
+        os.path.normcase(i).rstrip(os.sep) for i in
+        os.environ.get("PATH", "").split(os.pathsep)
+    ]
+    # If an executable sits with sys.executable, we don't warn for it.
+    #     This covers the case of venv invocations without activating the venv.
+    not_warn_dirs.append(os.path.normcase(os.path.dirname(sys.executable)))
+    warn_for = {
+        parent_dir: scripts for parent_dir, scripts in grouped_by_dir.items()
+        if os.path.normcase(parent_dir) not in not_warn_dirs
+    }  # type: Dict[str, Set[str]]
+    if not warn_for:
+        return None
+
+    # Format a message
+    msg_lines = []
+    for parent_dir, dir_scripts in warn_for.items():
+        sorted_scripts = sorted(dir_scripts)  # type: List[str]
+        if len(sorted_scripts) == 1:
+            start_text = "script {} is".format(sorted_scripts[0])
+        else:
+            start_text = "scripts {} are".format(
+                ", ".join(sorted_scripts[:-1]) + " and " + sorted_scripts[-1]
+            )
+
+        msg_lines.append(
+            "The {} installed in '{}' which is not on PATH."
+            .format(start_text, parent_dir)
+        )
+
+    last_line_fmt = (
+        "Consider adding {} to PATH or, if you prefer "
+        "to suppress this warning, use --no-warn-script-location."
+    )
+    if len(msg_lines) == 1:
+        msg_lines.append(last_line_fmt.format("this directory"))
+    else:
+        msg_lines.append(last_line_fmt.format("these directories"))
+
+    # Add a note if any directory starts with ~
+    warn_for_tilde = any(
+        i[0] == "~" for i in os.environ.get("PATH", "").split(os.pathsep) if i
+    )
+    if warn_for_tilde:
+        tilde_warning_msg = (
+            "NOTE: The current PATH contains path(s) starting with `~`, "
+            "which may not be expanded by all applications."
+        )
+        msg_lines.append(tilde_warning_msg)
+
+    # Returns the formatted multiline message
+    return "\n".join(msg_lines)
+
+
+def _normalized_outrows(outrows):
+    # type: (Iterable[InstalledCSVRow]) -> List[Tuple[str, str, str]]
+    """Normalize the given rows of a RECORD file.
+
+    Items in each row are converted into str. Rows are then sorted to make
+    the value more predictable for tests.
+
+    Each row is a 3-tuple (path, hash, size) and corresponds to a record of
+    a RECORD file (see PEP 376 and PEP 427 for details).  For the rows
+    passed to this function, the size can be an integer as an int or string,
+    or the empty string.
+    """
+    # Normally, there should only be one row per path, in which case the
+    # second and third elements don't come into play when sorting.
+    # However, in cases in the wild where a path might happen to occur twice,
+    # we don't want the sort operation to trigger an error (but still want
+    # determinism).  Since the third element can be an int or string, we
+    # coerce each element to a string to avoid a TypeError in this case.
+    # For additional background, see--
+    # https://github.com/pypa/pip/issues/5868
+    return sorted(
+        (ensure_str(record_path, encoding='utf-8'), hash_, str(size))
+        for record_path, hash_, size in outrows
+    )
+
+
+def _record_to_fs_path(record_path):
+    # type: (RecordPath) -> text_type
+    return record_path
+
+
+def _fs_to_record_path(path, relative_to=None):
+    # type: (text_type, Optional[text_type]) -> RecordPath
+    if relative_to is not None:
+        # On Windows, do not handle relative paths if they belong to different
+        # logical disks
+        if os.path.splitdrive(path)[0].lower() == \
+                os.path.splitdrive(relative_to)[0].lower():
+            path = os.path.relpath(path, relative_to)
+    path = path.replace(os.path.sep, '/')
+    return cast('RecordPath', path)
+
+
+def _parse_record_path(record_column):
+    # type: (str) -> RecordPath
+    p = ensure_text(record_column, encoding='utf-8')
+    return cast('RecordPath', p)
+
+
+def get_csv_rows_for_installed(
+    old_csv_rows,  # type: List[List[str]]
+    installed,  # type: Dict[RecordPath, RecordPath]
+    changed,  # type: Set[RecordPath]
+    generated,  # type: List[str]
+    lib_dir,  # type: str
+):
+    # type: (...) -> List[InstalledCSVRow]
+    """
+    :param installed: A map from archive RECORD path to installation RECORD
+        path.
+    """
+    installed_rows = []  # type: List[InstalledCSVRow]
+    for row in old_csv_rows:
+        if len(row) > 3:
+            logger.warning('RECORD line has more than three elements: %s', row)
+        old_record_path = _parse_record_path(row[0])
+        new_record_path = installed.pop(old_record_path, old_record_path)
+        if new_record_path in changed:
+            digest, length = rehash(_record_to_fs_path(new_record_path))
+        else:
+            digest = row[1] if len(row) > 1 else ''
+            length = row[2] if len(row) > 2 else ''
+        installed_rows.append((new_record_path, digest, length))
+    for f in generated:
+        path = _fs_to_record_path(f, lib_dir)
+        digest, length = rehash(f)
+        installed_rows.append((path, digest, length))
+    for installed_record_path in itervalues(installed):
+        installed_rows.append((installed_record_path, '', ''))
+    return installed_rows
+
+
+def get_console_script_specs(console):
+    # type: (Dict[str, str]) -> List[str]
+    """
+    Given the mapping from entrypoint name to callable, return the relevant
+    console script specs.
+    """
+    # Don't mutate caller's version
+    console = console.copy()
+
+    scripts_to_generate = []
+
+    # Special case pip and setuptools to generate versioned wrappers
+    #
+    # The issue is that some projects (specifically, pip and setuptools) use
+    # code in setup.py to create "versioned" entry points - pip2.7 on Python
+    # 2.7, pip3.3 on Python 3.3, etc. But these entry points are baked into
+    # the wheel metadata at build time, and so if the wheel is installed with
+    # a *different* version of Python the entry points will be wrong. The
+    # correct fix for this is to enhance the metadata to be able to describe
+    # such versioned entry points, but that won't happen till Metadata 2.0 is
+    # available.
+    # In the meantime, projects using versioned entry points will either have
+    # incorrect versioned entry points, or they will not be able to distribute
+    # "universal" wheels (i.e., they will need a wheel per Python version).
+    #
+    # Because setuptools and pip are bundled with _ensurepip and virtualenv,
+    # we need to use universal wheels. So, as a stopgap until Metadata 2.0, we
+    # override the versioned entry points in the wheel and generate the
+    # correct ones. This code is purely a short-term measure until Metadata 2.0
+    # is available.
+    #
+    # To add the level of hack in this section of code, in order to support
+    # ensurepip this code will look for an ``ENSUREPIP_OPTIONS`` environment
+    # variable which will control which version scripts get installed.
+    #
+    # ENSUREPIP_OPTIONS=altinstall
+    #   - Only pipX.Y and easy_install-X.Y will be generated and installed
+    # ENSUREPIP_OPTIONS=install
+    #   - pipX.Y, pipX, easy_install-X.Y will be generated and installed. Note
+    #     that this option is technically if ENSUREPIP_OPTIONS is set and is
+    #     not altinstall
+    # DEFAULT
+    #   - The default behavior is to install pip, pipX, pipX.Y, easy_install
+    #     and easy_install-X.Y.
+    pip_script = console.pop('pip', None)
+    if pip_script:
+        if "ENSUREPIP_OPTIONS" not in os.environ:
+            scripts_to_generate.append('pip = ' + pip_script)
+
+        if os.environ.get("ENSUREPIP_OPTIONS", "") != "altinstall":
+            scripts_to_generate.append(
+                'pip{} = {}'.format(sys.version_info[0], pip_script)
+            )
+
+        scripts_to_generate.append(
+            'pip{} = {}'.format(get_major_minor_version(), pip_script)
+        )
+        # Delete any other versioned pip entry points
+        pip_ep = [k for k in console if re.match(r'pip(\d(\.\d)?)?$', k)]
+        for k in pip_ep:
+            del console[k]
+    easy_install_script = console.pop('easy_install', None)
+    if easy_install_script:
+        if "ENSUREPIP_OPTIONS" not in os.environ:
+            scripts_to_generate.append(
+                'easy_install = ' + easy_install_script
+            )
+
+        scripts_to_generate.append(
+            'easy_install-{} = {}'.format(
+                get_major_minor_version(), easy_install_script
+            )
+        )
+        # Delete any other versioned easy_install entry points
+        easy_install_ep = [
+            k for k in console if re.match(r'easy_install(-\d\.\d)?$', k)
+        ]
+        for k in easy_install_ep:
+            del console[k]
+
+    # Generate the console entry points specified in the wheel
+    scripts_to_generate.extend(starmap('{} = {}'.format, console.items()))
+
+    return scripts_to_generate
+
+
+class ZipBackedFile(object):
+    def __init__(self, src_record_path, dest_path, zip_file):
+        # type: (RecordPath, text_type, ZipFile) -> None
+        self.src_record_path = src_record_path
+        self.dest_path = dest_path
+        self._zip_file = zip_file
+        self.changed = False
+
+    def _getinfo(self):
+        # type: () -> ZipInfo
+        if not PY2:
+            return self._zip_file.getinfo(self.src_record_path)
+        # Python 2 does not expose a way to detect a ZIP's encoding, but the
+        # wheel specification (PEP 427) explicitly mandates that paths should
+        # use UTF-8, so we assume it is true.
+        return self._zip_file.getinfo(self.src_record_path.encode("utf-8"))
+
+    def save(self):
+        # type: () -> None
+        # directory creation is lazy and after file filtering
+        # to ensure we don't install empty dirs; empty dirs can't be
+        # uninstalled.
+        parent_dir = os.path.dirname(self.dest_path)
+        ensure_dir(parent_dir)
+
+        # When we open the output file below, any existing file is truncated
+        # before we start writing the new contents. This is fine in most
+        # cases, but can cause a segfault if pip has loaded a shared
+        # object (e.g. from pyopenssl through its vendored urllib3)
+        # Since the shared object is mmap'd an attempt to call a
+        # symbol in it will then cause a segfault. Unlinking the file
+        # allows writing of new contents while allowing the process to
+        # continue to use the old copy.
+        if os.path.exists(self.dest_path):
+            os.unlink(self.dest_path)
+
+        zipinfo = self._getinfo()
+
+        with self._zip_file.open(zipinfo) as f:
+            with open(self.dest_path, "wb") as dest:
+                shutil.copyfileobj(f, dest)
+
+        if zip_item_is_executable(zipinfo):
+            set_extracted_file_to_default_mode_plus_executable(self.dest_path)
+
+
+class ScriptFile(object):
+    def __init__(self, file):
+        # type: (File) -> None
+        self._file = file
+        self.src_record_path = self._file.src_record_path
+        self.dest_path = self._file.dest_path
+        self.changed = False
+
+    def save(self):
+        # type: () -> None
+        self._file.save()
+        self.changed = fix_script(self.dest_path)
+
+
+class MissingCallableSuffix(InstallationError):
+    def __init__(self, entry_point):
+        # type: (str) -> None
+        super(MissingCallableSuffix, self).__init__(
+            "Invalid script entry point: {} - A callable "
+            "suffix is required. Cf https://packaging.python.org/"
+            "specifications/entry-points/#use-for-scripts for more "
+            "information.".format(entry_point)
+        )
+
+
+def _raise_for_invalid_entrypoint(specification):
+    # type: (str) -> None
+    entry = get_export_entry(specification)
+    if entry is not None and entry.suffix is None:
+        raise MissingCallableSuffix(str(entry))
+
+
+class PipScriptMaker(ScriptMaker):
+    def make(self, specification, options=None):
+        # type: (str, Dict[str, Any]) -> List[str]
+        _raise_for_invalid_entrypoint(specification)
+        return super(PipScriptMaker, self).make(specification, options)
+
+
+def _install_wheel(
+    name,  # type: str
+    wheel_zip,  # type: ZipFile
+    wheel_path,  # type: str
+    scheme,  # type: Scheme
+    pycompile=True,  # type: bool
+    warn_script_location=True,  # type: bool
+    direct_url=None,  # type: Optional[DirectUrl]
+    requested=False,  # type: bool
+):
+    # type: (...) -> None
+    """Install a wheel.
+
+    :param name: Name of the project to install
+    :param wheel_zip: open ZipFile for wheel being installed
+    :param scheme: Distutils scheme dictating the install directories
+    :param req_description: String used in place of the requirement, for
+        logging
+    :param pycompile: Whether to byte-compile installed Python files
+    :param warn_script_location: Whether to check that scripts are installed
+        into a directory on PATH
+    :raises UnsupportedWheel:
+        * when the directory holds an unpacked wheel with incompatible
+          Wheel-Version
+        * when the .dist-info dir does not match the wheel
+    """
+    info_dir, metadata = parse_wheel(wheel_zip, name)
+
+    if wheel_root_is_purelib(metadata):
+        lib_dir = scheme.purelib
+    else:
+        lib_dir = scheme.platlib
+
+    # Record details of the files moved
+    #   installed = files copied from the wheel to the destination
+    #   changed = files changed while installing (scripts #! line typically)
+    #   generated = files newly generated during the install (script wrappers)
+    installed = {}  # type: Dict[RecordPath, RecordPath]
+    changed = set()  # type: Set[RecordPath]
+    generated = []  # type: List[str]
+
+    def record_installed(srcfile, destfile, modified=False):
+        # type: (RecordPath, text_type, bool) -> None
+        """Map archive RECORD paths to installation RECORD paths."""
+        newpath = _fs_to_record_path(destfile, lib_dir)
+        installed[srcfile] = newpath
+        if modified:
+            changed.add(_fs_to_record_path(destfile))
+
+    def all_paths():
+        # type: () -> Iterable[RecordPath]
+        names = wheel_zip.namelist()
+        # If a flag is set, names may be unicode in Python 2. We convert to
+        # text explicitly so these are valid for lookup in RECORD.
+        decoded_names = map(ensure_text, names)
+        for name in decoded_names:
+            yield cast("RecordPath", name)
+
+    def is_dir_path(path):
+        # type: (RecordPath) -> bool
+        return path.endswith("/")
+
+    def assert_no_path_traversal(dest_dir_path, target_path):
+        # type: (text_type, text_type) -> None
+        if not is_within_directory(dest_dir_path, target_path):
+            message = (
+                "The wheel {!r} has a file {!r} trying to install"
+                " outside the target directory {!r}"
+            )
+            raise InstallationError(
+                message.format(wheel_path, target_path, dest_dir_path)
+            )
+
+    def root_scheme_file_maker(zip_file, dest):
+        # type: (ZipFile, text_type) -> Callable[[RecordPath], File]
+        def make_root_scheme_file(record_path):
+            # type: (RecordPath) -> File
+            normed_path = os.path.normpath(record_path)
+            dest_path = os.path.join(dest, normed_path)
+            assert_no_path_traversal(dest, dest_path)
+            return ZipBackedFile(record_path, dest_path, zip_file)
+
+        return make_root_scheme_file
+
+    def data_scheme_file_maker(zip_file, scheme):
+        # type: (ZipFile, Scheme) -> Callable[[RecordPath], File]
+        scheme_paths = {}
+        for key in SCHEME_KEYS:
+            encoded_key = ensure_text(key)
+            scheme_paths[encoded_key] = ensure_text(
+                getattr(scheme, key), encoding=sys.getfilesystemencoding()
+            )
+
+        def make_data_scheme_file(record_path):
+            # type: (RecordPath) -> File
+            normed_path = os.path.normpath(record_path)
+            try:
+                _, scheme_key, dest_subpath = normed_path.split(os.path.sep, 2)
+            except ValueError:
+                message = (
+                    "Unexpected file in {}: {!r}. .data directory contents"
+                    " should be named like: '<scheme key>/<path>'."
+                ).format(wheel_path, record_path)
+                raise InstallationError(message)
+
+            try:
+                scheme_path = scheme_paths[scheme_key]
+            except KeyError:
+                valid_scheme_keys = ", ".join(sorted(scheme_paths))
+                message = (
+                    "Unknown scheme key used in {}: {} (for file {!r}). .data"
+                    " directory contents should be in subdirectories named"
+                    " with a valid scheme key ({})"
+                ).format(
+                    wheel_path, scheme_key, record_path, valid_scheme_keys
+                )
+                raise InstallationError(message)
+
+            dest_path = os.path.join(scheme_path, dest_subpath)
+            assert_no_path_traversal(scheme_path, dest_path)
+            return ZipBackedFile(record_path, dest_path, zip_file)
+
+        return make_data_scheme_file
+
+    def is_data_scheme_path(path):
+        # type: (RecordPath) -> bool
+        return path.split("/", 1)[0].endswith(".data")
+
+    paths = all_paths()
+    file_paths = filterfalse(is_dir_path, paths)
+    root_scheme_paths, data_scheme_paths = partition(
+        is_data_scheme_path, file_paths
+    )
+
+    make_root_scheme_file = root_scheme_file_maker(
+        wheel_zip,
+        ensure_text(lib_dir, encoding=sys.getfilesystemencoding()),
+    )
+    files = map(make_root_scheme_file, root_scheme_paths)
+
+    def is_script_scheme_path(path):
+        # type: (RecordPath) -> bool
+        parts = path.split("/", 2)
+        return (
+            len(parts) > 2 and
+            parts[0].endswith(".data") and
+            parts[1] == "scripts"
+        )
+
+    other_scheme_paths, script_scheme_paths = partition(
+        is_script_scheme_path, data_scheme_paths
+    )
+
+    make_data_scheme_file = data_scheme_file_maker(wheel_zip, scheme)
+    other_scheme_files = map(make_data_scheme_file, other_scheme_paths)
+    files = chain(files, other_scheme_files)
+
+    # Get the defined entry points
+    distribution = pkg_resources_distribution_for_wheel(
+        wheel_zip, name, wheel_path
+    )
+    console, gui = get_entrypoints(distribution)
+
+    def is_entrypoint_wrapper(file):
+        # type: (File) -> bool
+        # EP, EP.exe and EP-script.py are scripts generated for
+        # entry point EP by setuptools
+        path = file.dest_path
+        name = os.path.basename(path)
+        if name.lower().endswith('.exe'):
+            matchname = name[:-4]
+        elif name.lower().endswith('-script.py'):
+            matchname = name[:-10]
+        elif name.lower().endswith(".pya"):
+            matchname = name[:-4]
+        else:
+            matchname = name
+        # Ignore setuptools-generated scripts
+        return (matchname in console or matchname in gui)
+
+    script_scheme_files = map(make_data_scheme_file, script_scheme_paths)
+    script_scheme_files = filterfalse(
+        is_entrypoint_wrapper, script_scheme_files
+    )
+    script_scheme_files = map(ScriptFile, script_scheme_files)
+    files = chain(files, script_scheme_files)
+
+    for file in files:
+        file.save()
+        record_installed(file.src_record_path, file.dest_path, file.changed)
+
+    def pyc_source_file_paths():
+        # type: () -> Iterator[text_type]
+        # We de-duplicate installation paths, since there can be overlap (e.g.
+        # file in .data maps to same location as file in wheel root).
+        # Sorting installation paths makes it easier to reproduce and debug
+        # issues related to permissions on existing files.
+        for installed_path in sorted(set(installed.values())):
+            full_installed_path = os.path.join(lib_dir, installed_path)
+            if not os.path.isfile(full_installed_path):
+                continue
+            if not full_installed_path.endswith('.py'):
+                continue
+            yield full_installed_path
+
+    def pyc_output_path(path):
+        # type: (text_type) -> text_type
+        """Return the path the pyc file would have been written to.
+        """
+        if PY2:
+            if sys.flags.optimize:
+                return path + 'o'
+            else:
+                return path + 'c'
+        else:
+            return importlib.util.cache_from_source(path)
+
+    # Compile all of the pyc files for the installed files
+    if pycompile:
+        with captured_stdout() as stdout:
+            with warnings.catch_warnings():
+                warnings.filterwarnings('ignore')
+                for path in pyc_source_file_paths():
+                    # Python 2's `compileall.compile_file` requires a str in
+                    # error cases, so we must convert to the native type.
+                    path_arg = ensure_str(
+                        path, encoding=sys.getfilesystemencoding()
+                    )
+                    success = compileall.compile_file(
+                        path_arg, force=True, quiet=True
+                    )
+                    if success:
+                        pyc_path = pyc_output_path(path)
+                        assert os.path.exists(pyc_path)
+                        pyc_record_path = cast(
+                            "RecordPath", pyc_path.replace(os.path.sep, "/")
+                        )
+                        record_installed(pyc_record_path, pyc_path)
+        logger.debug(stdout.getvalue())
+
+    maker = PipScriptMaker(None, scheme.scripts)
+
+    # Ensure old scripts are overwritten.
+    # See https://github.com/pypa/pip/issues/1800
+    maker.clobber = True
+
+    # Ensure we don't generate any variants for scripts because this is almost
+    # never what somebody wants.
+    # See https://bitbucket.org/pypa/distlib/issue/35/
+    maker.variants = {''}
+
+    # This is required because otherwise distlib creates scripts that are not
+    # executable.
+    # See https://bitbucket.org/pypa/distlib/issue/32/
+    maker.set_mode = True
+
+    # Generate the console and GUI entry points specified in the wheel
+    scripts_to_generate = get_console_script_specs(console)
+
+    gui_scripts_to_generate = list(starmap('{} = {}'.format, gui.items()))
+
+    generated_console_scripts = maker.make_multiple(scripts_to_generate)
+    generated.extend(generated_console_scripts)
+
+    generated.extend(
+        maker.make_multiple(gui_scripts_to_generate, {'gui': True})
+    )
+
+    if warn_script_location:
+        msg = message_about_scripts_not_on_PATH(generated_console_scripts)
+        if msg is not None:
+            logger.warning(msg)
+
+    generated_file_mode = 0o666 & ~current_umask()
+
+    @contextlib.contextmanager
+    def _generate_file(path, **kwargs):
+        # type: (str, **Any) -> Iterator[NamedTemporaryFileResult]
+        with adjacent_tmp_file(path, **kwargs) as f:
+            yield f
+        os.chmod(f.name, generated_file_mode)
+        replace(f.name, path)
+
+    dest_info_dir = os.path.join(lib_dir, info_dir)
+
+    # Record pip as the installer
+    installer_path = os.path.join(dest_info_dir, 'INSTALLER')
+    with _generate_file(installer_path) as installer_file:
+        installer_file.write(b'pip\n')
+    generated.append(installer_path)
+
+    # Record the PEP 610 direct URL reference
+    if direct_url is not None:
+        direct_url_path = os.path.join(dest_info_dir, DIRECT_URL_METADATA_NAME)
+        with _generate_file(direct_url_path) as direct_url_file:
+            direct_url_file.write(direct_url.to_json().encode("utf-8"))
+        generated.append(direct_url_path)
+
+    # Record the REQUESTED file
+    if requested:
+        requested_path = os.path.join(dest_info_dir, 'REQUESTED')
+        with open(requested_path, "w"):
+            pass
+        generated.append(requested_path)
+
+    record_text = distribution.get_metadata('RECORD')
+    record_rows = list(csv.reader(record_text.splitlines()))
+
+    rows = get_csv_rows_for_installed(
+        record_rows,
+        installed=installed,
+        changed=changed,
+        generated=generated,
+        lib_dir=lib_dir)
+
+    # Record details of all files installed
+    record_path = os.path.join(dest_info_dir, 'RECORD')
+
+    with _generate_file(record_path, **csv_io_kwargs('w')) as record_file:
+        # The type mypy infers for record_file is different for Python 3
+        # (typing.IO[Any]) and Python 2 (typing.BinaryIO). We explicitly
+        # cast to typing.IO[str] as a workaround.
+        writer = csv.writer(cast('IO[str]', record_file))
+        writer.writerows(_normalized_outrows(rows))
+
+
+@contextlib.contextmanager
+def req_error_context(req_description):
+    # type: (str) -> Iterator[None]
+    try:
+        yield
+    except InstallationError as e:
+        message = "For req: {}. {}".format(req_description, e.args[0])
+        reraise(
+            InstallationError, InstallationError(message), sys.exc_info()[2]
+        )
+
+
+def install_wheel(
+    name,  # type: str
+    wheel_path,  # type: str
+    scheme,  # type: Scheme
+    req_description,  # type: str
+    pycompile=True,  # type: bool
+    warn_script_location=True,  # type: bool
+    direct_url=None,  # type: Optional[DirectUrl]
+    requested=False,  # type: bool
+):
+    # type: (...) -> None
+    with ZipFile(wheel_path, allowZip64=True) as z:
+        with req_error_context(req_description):
+            _install_wheel(
+                name=name,
+                wheel_zip=z,
+                wheel_path=wheel_path,
+                scheme=scheme,
+                pycompile=pycompile,
+                warn_script_location=warn_script_location,
+                direct_url=direct_url,
+                requested=requested,
+            )

venv/Lib/site-packages/pip/_internal/operations/prepare.py

@@ -0,0 +1,562 @@
+"""Prepares a distribution for installation
+"""
+
+# The following comment should be removed at some point in the future.
+# mypy: strict-optional=False
+
+import logging
+import mimetypes
+import os
+import shutil
+
+from pip._vendor.six import PY2
+
+from pip._internal.distributions import (
+    make_distribution_for_install_requirement,
+)
+from pip._internal.distributions.installed import InstalledDistribution
+from pip._internal.exceptions import (
+    DirectoryUrlHashUnsupported,
+    HashMismatch,
+    HashUnpinned,
+    InstallationError,
+    NetworkConnectionError,
+    PreviousBuildDirError,
+    VcsHashUnsupported,
+)
+from pip._internal.utils.filesystem import copy2_fixed
+from pip._internal.utils.hashes import MissingHashes
+from pip._internal.utils.logging import indent_log
+from pip._internal.utils.misc import (
+    display_path,
+    hide_url,
+    path_to_display,
+    rmtree,
+)
+from pip._internal.utils.temp_dir import TempDirectory
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
+from pip._internal.utils.unpacking import unpack_file
+from pip._internal.vcs import vcs
+
+if MYPY_CHECK_RUNNING:
+    from typing import (
+        Callable, List, Optional, Tuple,
+    )
+
+    from mypy_extensions import TypedDict
+
+    from pip._internal.distributions import AbstractDistribution
+    from pip._internal.index.package_finder import PackageFinder
+    from pip._internal.models.link import Link
+    from pip._internal.network.download import Downloader
+    from pip._internal.req.req_install import InstallRequirement
+    from pip._internal.req.req_tracker import RequirementTracker
+    from pip._internal.utils.hashes import Hashes
+
+    if PY2:
+        CopytreeKwargs = TypedDict(
+            'CopytreeKwargs',
+            {
+                'ignore': Callable[[str, List[str]], List[str]],
+                'symlinks': bool,
+            },
+            total=False,
+        )
+    else:
+        CopytreeKwargs = TypedDict(
+            'CopytreeKwargs',
+            {
+                'copy_function': Callable[[str, str], None],
+                'ignore': Callable[[str, List[str]], List[str]],
+                'ignore_dangling_symlinks': bool,
+                'symlinks': bool,
+            },
+            total=False,
+        )
+
+logger = logging.getLogger(__name__)
+
+
+def _get_prepared_distribution(
+        req,  # type: InstallRequirement
+        req_tracker,  # type: RequirementTracker
+        finder,  # type: PackageFinder
+        build_isolation  # type: bool
+):
+    # type: (...) -> AbstractDistribution
+    """Prepare a distribution for installation.
+    """
+    abstract_dist = make_distribution_for_install_requirement(req)
+    with req_tracker.track(req):
+        abstract_dist.prepare_distribution_metadata(finder, build_isolation)
+    return abstract_dist
+
+
+def unpack_vcs_link(link, location):
+    # type: (Link, str) -> None
+    vcs_backend = vcs.get_backend_for_scheme(link.scheme)
+    assert vcs_backend is not None
+    vcs_backend.unpack(location, url=hide_url(link.url))
+
+
+class File(object):
+    def __init__(self, path, content_type):
+        # type: (str, str) -> None
+        self.path = path
+        self.content_type = content_type
+
+
+def get_http_url(
+    link,  # type: Link
+    downloader,  # type: Downloader
+    download_dir=None,  # type: Optional[str]
+    hashes=None,  # type: Optional[Hashes]
+):
+    # type: (...) -> File
+    temp_dir = TempDirectory(kind="unpack", globally_managed=True)
+    # If a download dir is specified, is the file already downloaded there?
+    already_downloaded_path = None
+    if download_dir:
+        already_downloaded_path = _check_download_dir(
+            link, download_dir, hashes
+        )
+
+    if already_downloaded_path:
+        from_path = already_downloaded_path
+        content_type = mimetypes.guess_type(from_path)[0]
+    else:
+        # let's download to a tmp dir
+        from_path, content_type = _download_http_url(
+            link, downloader, temp_dir.path, hashes
+        )
+
+    return File(from_path, content_type)
+
+
+def _copy2_ignoring_special_files(src, dest):
+    # type: (str, str) -> None
+    """Copying special files is not supported, but as a convenience to users
+    we skip errors copying them. This supports tools that may create e.g.
+    socket files in the project source directory.
+    """
+    try:
+        copy2_fixed(src, dest)
+    except shutil.SpecialFileError as e:
+        # SpecialFileError may be raised due to either the source or
+        # destination. If the destination was the cause then we would actually
+        # care, but since the destination directory is deleted prior to
+        # copy we ignore all of them assuming it is caused by the source.
+        logger.warning(
+            "Ignoring special file error '%s' encountered copying %s to %s.",
+            str(e),
+            path_to_display(src),
+            path_to_display(dest),
+        )
+
+
+def _copy_source_tree(source, target):
+    # type: (str, str) -> None
+    target_abspath = os.path.abspath(target)
+    target_basename = os.path.basename(target_abspath)
+    target_dirname = os.path.dirname(target_abspath)
+
+    def ignore(d, names):
+        # type: (str, List[str]) -> List[str]
+        skipped = []  # type: List[str]
+        if d == source:
+            # Pulling in those directories can potentially be very slow,
+            # exclude the following directories if they appear in the top
+            # level dir (and only it).
+            # See discussion at https://github.com/pypa/pip/pull/6770
+            skipped += ['.tox', '.nox']
+        if os.path.abspath(d) == target_dirname:
+            # Prevent an infinite recursion if the target is in source.
+            # This can happen when TMPDIR is set to ${PWD}/...
+            # and we copy PWD to TMPDIR.
+            skipped += [target_basename]
+        return skipped
+
+    kwargs = dict(ignore=ignore, symlinks=True)  # type: CopytreeKwargs
+
+    if not PY2:
+        # Python 2 does not support copy_function, so we only ignore
+        # errors on special file copy in Python 3.
+        kwargs['copy_function'] = _copy2_ignoring_special_files
+
+    shutil.copytree(source, target, **kwargs)
+
+
+def get_file_url(
+    link,  # type: Link
+    download_dir=None,  # type: Optional[str]
+    hashes=None  # type: Optional[Hashes]
+):
+    # type: (...) -> File
+    """Get file and optionally check its hash.
+    """
+    # If a download dir is specified, is the file already there and valid?
+    already_downloaded_path = None
+    if download_dir:
+        already_downloaded_path = _check_download_dir(
+            link, download_dir, hashes
+        )
+
+    if already_downloaded_path:
+        from_path = already_downloaded_path
+    else:
+        from_path = link.file_path
+
+    # If --require-hashes is off, `hashes` is either empty, the
+    # link's embedded hash, or MissingHashes; it is required to
+    # match. If --require-hashes is on, we are satisfied by any
+    # hash in `hashes` matching: a URL-based or an option-based
+    # one; no internet-sourced hash will be in `hashes`.
+    if hashes:
+        hashes.check_against_path(from_path)
+
+    content_type = mimetypes.guess_type(from_path)[0]
+
+    return File(from_path, content_type)
+
+
+def unpack_url(
+    link,  # type: Link
+    location,  # type: str
+    downloader,  # type: Downloader
+    download_dir=None,  # type: Optional[str]
+    hashes=None,  # type: Optional[Hashes]
+):
+    # type: (...) -> Optional[File]
+    """Unpack link into location, downloading if required.
+
+    :param hashes: A Hashes object, one of whose embedded hashes must match,
+        or HashMismatch will be raised. If the Hashes is empty, no matches are
+        required, and unhashable types of requirements (like VCS ones, which
+        would ordinarily raise HashUnsupported) are allowed.
+    """
+    # non-editable vcs urls
+    if link.is_vcs:
+        unpack_vcs_link(link, location)
+        return None
+
+    # If it's a url to a local directory
+    if link.is_existing_dir():
+        if os.path.isdir(location):
+            rmtree(location)
+        _copy_source_tree(link.file_path, location)
+        return None
+
+    # file urls
+    if link.is_file:
+        file = get_file_url(link, download_dir, hashes=hashes)
+
+    # http urls
+    else:
+        file = get_http_url(
+            link,
+            downloader,
+            download_dir,
+            hashes=hashes,
+        )
+
+    # unpack the archive to the build dir location. even when only downloading
+    # archives, they have to be unpacked to parse dependencies, except wheels
+    if not link.is_wheel:
+        unpack_file(file.path, location, file.content_type)
+
+    return file
+
+
+def _download_http_url(
+    link,  # type: Link
+    downloader,  # type: Downloader
+    temp_dir,  # type: str
+    hashes,  # type: Optional[Hashes]
+):
+    # type: (...) -> Tuple[str, str]
+    """Download link url into temp_dir using provided session"""
+    download = downloader(link)
+
+    file_path = os.path.join(temp_dir, download.filename)
+    with open(file_path, 'wb') as content_file:
+        for chunk in download.chunks:
+            content_file.write(chunk)
+
+    if hashes:
+        hashes.check_against_path(file_path)
+
+    return file_path, download.response.headers.get('content-type', '')
+
+
+def _check_download_dir(link, download_dir, hashes):
+    # type: (Link, str, Optional[Hashes]) -> Optional[str]
+    """ Check download_dir for previously downloaded file with correct hash
+        If a correct file is found return its path else None
+    """
+    download_path = os.path.join(download_dir, link.filename)
+
+    if not os.path.exists(download_path):
+        return None
+
+    # If already downloaded, does its hash match?
+    logger.info('File was already downloaded %s', download_path)
+    if hashes:
+        try:
+            hashes.check_against_path(download_path)
+        except HashMismatch:
+            logger.warning(
+                'Previously-downloaded file %s has bad hash. '
+                'Re-downloading.',
+                download_path
+            )
+            os.unlink(download_path)
+            return None
+    return download_path
+
+
+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]
+        build_isolation,  # type: bool
+        req_tracker,  # type: RequirementTracker
+        downloader,  # type: Downloader
+        finder,  # type: PackageFinder
+        require_hashes,  # type: bool
+        use_user_site,  # type: bool
+    ):
+        # type: (...) -> None
+        super(RequirementPreparer, self).__init__()
+
+        self.src_dir = src_dir
+        self.build_dir = build_dir
+        self.req_tracker = req_tracker
+        self.downloader = downloader
+        self.finder = finder
+
+        # 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.
+        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'.
+
+        # Is build isolation allowed?
+        self.build_isolation = build_isolation
+
+        # Should hash-checking be required?
+        self.require_hashes = require_hashes
+
+        # Should install in user site-packages?
+        self.use_user_site = use_user_site
+
+    @property
+    def _download_should_save(self):
+        # type: () -> bool
+        if not self.download_dir:
+            return False
+
+        if os.path.exists(self.download_dir):
+            return True
+
+        logger.critical('Could not find download directory')
+        raise InstallationError(
+            "Could not find or access download directory '{}'"
+            .format(self.download_dir))
+
+    def _log_preparing_link(self, req):
+        # type: (InstallRequirement) -> None
+        """Log the way the link prepared."""
+        if req.link.is_file:
+            path = req.link.file_path
+            logger.info('Processing %s', display_path(path))
+        else:
+            logger.info('Collecting %s', req.req or req)
+
+    def _ensure_link_req_src_dir(self, req, download_dir, parallel_builds):
+        # type: (InstallRequirement, Optional[str], bool) -> None
+        """Ensure source_dir of a linked InstallRequirement."""
+        # Since source_dir is only set for editable requirements.
+        if req.link.is_wheel:
+            # We don't need to unpack wheels, so no need for a source
+            # directory.
+            return
+        assert req.source_dir is None
+        # We always delete unpacked sdists after pip runs.
+        req.ensure_has_source_dir(
+            self.build_dir,
+            autodelete=True,
+            parallel_builds=parallel_builds,
+        )
+
+        # 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`
+        if os.path.exists(os.path.join(req.source_dir, 'setup.py')):
+            raise PreviousBuildDirError(
+                "pip can't proceed with requirements '{}' due to a"
+                "pre-existing build directory ({}). 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.".format(req, req.source_dir)
+            )
+
+    def _get_linked_req_hashes(self, req):
+        # type: (InstallRequirement) -> Hashes
+        # By the time this is called, the requirement's link should have
+        # been checked so we can tell what kind of requirements req is
+        # and raise some more informative errors than otherwise.
+        # (For example, we can raise VcsHashUnsupported for a VCS URL
+        # rather than HashMissing.)
+        if not self.require_hashes:
+            return req.hashes(trust_internet=True)
+
+        # 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 req.link.is_vcs:
+            raise VcsHashUnsupported()
+        if req.link.is_existing_dir():
+            raise DirectoryUrlHashUnsupported()
+
+        # 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.
+        if req.original_link is None and not req.is_pinned:
+            raise HashUnpinned()
+
+        # If known-good hashes are missing for this requirement,
+        # 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.
+        return req.hashes(trust_internet=False) or MissingHashes()
+
+    def prepare_linked_requirement(self, req, parallel_builds=False):
+        # type: (InstallRequirement, bool) -> AbstractDistribution
+        """Prepare a requirement to be obtained from req.link."""
+        assert req.link
+        link = req.link
+        self._log_preparing_link(req)
+        if link.is_wheel and self.wheel_download_dir:
+            # Download wheels to a dedicated dir when doing `pip wheel`.
+            download_dir = self.wheel_download_dir
+        else:
+            download_dir = self.download_dir
+
+        with indent_log():
+            self._ensure_link_req_src_dir(req, download_dir, parallel_builds)
+            try:
+                local_file = unpack_url(
+                    link, req.source_dir, self.downloader, download_dir,
+                    hashes=self._get_linked_req_hashes(req)
+                )
+            except NetworkConnectionError as exc:
+                raise InstallationError(
+                    'Could not install requirement {} because of HTTP '
+                    'error {} for URL {}'.format(req, exc, link)
+                )
+
+            # For use in later processing, preserve the file path on the
+            # requirement.
+            if local_file:
+                req.local_file_path = local_file.path
+
+            abstract_dist = _get_prepared_distribution(
+                req, self.req_tracker, self.finder, self.build_isolation,
+            )
+
+            if download_dir:
+                if link.is_existing_dir():
+                    logger.info('Link is a directory, ignoring download_dir')
+                elif local_file:
+                    download_location = os.path.join(
+                        download_dir, link.filename
+                    )
+                    if not os.path.exists(download_location):
+                        shutil.copy(local_file.path, download_location)
+                        download_path = display_path(download_location)
+                        logger.info('Saved %s', download_path)
+
+            if self._download_should_save:
+                # Make a .zip of the source_dir we already created.
+                if link.is_vcs:
+                    req.archive(self.download_dir)
+        return abstract_dist
+
+    def prepare_editable_requirement(
+        self,
+        req,  # type: InstallRequirement
+    ):
+        # 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 self.require_hashes:
+                raise InstallationError(
+                    'The editable requirement {} cannot be installed when '
+                    'requiring hashes, because there is no single file to '
+                    'hash.'.format(req)
+                )
+            req.ensure_has_source_dir(self.src_dir)
+            req.update_editable(not self._download_should_save)
+
+            abstract_dist = _get_prepared_distribution(
+                req, self.req_tracker, self.finder, self.build_isolation,
+            )
+
+            if self._download_should_save:
+                req.archive(self.download_dir)
+            req.check_if_exists(self.use_user_site)
+
+        return abstract_dist
+
+    def prepare_installed_requirement(
+        self,
+        req,  # type: InstallRequirement
+        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 {}".format(req.satisfied_by)
+        )
+        logger.info(
+            'Requirement %s: %s (%s)',
+            skip_reason, req, req.satisfied_by.version
+        )
+        with indent_log():
+            if self.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