Move InstallRequirement.from_editable to a constructors module

src/pip/_internal/cli/base_command.py

@@ -22,6 +22,7 @@
 )
 from pip._internal.index import PackageFinder
 from pip._internal.locations import running_under_virtualenv
+from pip._internal.req.constructors import install_req_from_editable
 from pip._internal.req.req_file import parse_requirements
 from pip._internal.req.req_install import InstallRequirement
 from pip._internal.utils.logging import setup_logging
@@ -216,7 +217,7 @@ def populate_requirement_set(requirement_set, args, options, finder,
             requirement_set.add_requirement(req_to_add)
 
         for req in options.editables:
-            req_to_add = InstallRequirement.from_editable(
+            req_to_add = install_req_from_editable(
                 req,
                 isolated=options.isolated_mode,
                 wheel_cache=wheel_cache

src/pip/_internal/operations/freeze.py

@@ -11,6 +11,7 @@
 
 from pip._internal.exceptions import InstallationError
 from pip._internal.req import InstallRequirement
+from pip._internal.req.constructors import install_req_from_editable
 from pip._internal.req.req_file import COMMENT_RE
 from pip._internal.utils.deprecation import deprecated
 from pip._internal.utils.misc import (
@@ -99,7 +100,7 @@ def freeze(
                             line = line[2:].strip()
                         else:
                             line = line[len('--editable'):].strip().lstrip('=')
-                        line_req = InstallRequirement.from_editable(
+                        line_req = install_req_from_editable(
                             line,
                             isolated=isolated,
                             wheel_cache=wheel_cache,

src/pip/_internal/req/constructors.py

@@ -0,0 +1,116 @@
+"""Backing implementation for InstallRequirement's various constructors
+
+The idea here is that these formed a major chunk of InstallRequirement's size
+so, moving them and support code dedicated to them outside of that class
+helps creates for better understandability for the rest of the code.
+
+These are meant to be used elsewhere within pip to create instances of
+InstallRequirement.
+"""
+
+import os
+
+from pip._vendor.packaging.requirements import InvalidRequirement, Requirement
+
+# XXX: Temporarily importing _strip_extras
+from pip._internal.download import path_to_url, url_to_path
+from pip._internal.exceptions import InstallationError
+from pip._internal.models.link import Link
+from pip._internal.req.req_install import InstallRequirement, _strip_extras
+from pip._internal.vcs import vcs
+
+__all__ = ["install_req_from_editable", "parse_editable"]
+
+
+def parse_editable(editable_req):
+    """Parses an editable requirement into:
+        - a requirement name
+        - an URL
+        - extras
+        - editable options
+    Accepted requirements:
+        svn+http://blahblah@rev#egg=Foobar[baz]&subdirectory=version_subdir
+        .[some_extra]
+    """
+
+    url = editable_req
+
+    # If a file path is specified with extras, strip off the extras.
+    url_no_extras, extras = _strip_extras(url)
+
+    if os.path.isdir(url_no_extras):
+        if not os.path.exists(os.path.join(url_no_extras, 'setup.py')):
+            raise InstallationError(
+                "Directory %r is not installable. File 'setup.py' not found." %
+                url_no_extras
+            )
+        # Treating it as code that has already been checked out
+        url_no_extras = path_to_url(url_no_extras)
+
+    if url_no_extras.lower().startswith('file:'):
+        package_name = Link(url_no_extras).egg_fragment
+        if extras:
+            return (
+                package_name,
+                url_no_extras,
+                Requirement("placeholder" + extras.lower()).extras,
+            )
+        else:
+            return package_name, url_no_extras, None
+
+    for version_control in vcs:
+        if url.lower().startswith('%s:' % version_control):
+            url = '%s+%s' % (version_control, url)
+            break
+
+    if '+' not in url:
+        raise InstallationError(
+            '%s should either be a path to a local project or a VCS url '
+            'beginning with svn+, git+, hg+, or bzr+' %
+            editable_req
+        )
+
+    vc_type = url.split('+', 1)[0].lower()
+
+    if not vcs.get_backend(vc_type):
+        error_message = 'For --editable=%s only ' % editable_req + \
+            ', '.join([backend.name + '+URL' for backend in vcs.backends]) + \
+            ' is currently supported'
+        raise InstallationError(error_message)
+
+    package_name = Link(url).egg_fragment
+    if not package_name:
+        raise InstallationError(
+            "Could not detect requirement name for '%s', please specify one "
+            "with #egg=your_package_name" % editable_req
+        )
+    return package_name, url, None
+
+
+def install_req_from_editable(
+    editable_req, comes_from=None, isolated=False, options=None,
+    wheel_cache=None, constraint=False
+):
+    name, url, extras_override = parse_editable(editable_req)
+    if url.startswith('file:'):
+        source_dir = url_to_path(url)
+    else:
+        source_dir = None
+
+    if name is not None:
+        try:
+            req = Requirement(name)
+        except InvalidRequirement:
+            raise InstallationError("Invalid requirement: '%s'" % name)
+    else:
+        req = None
+    return InstallRequirement(
+        req, comes_from, source_dir=source_dir,
+        editable=True,
+        link=Link(url),
+        constraint=constraint,
+        isolated=isolated,
+        options=options if options else {},
+        wheel_cache=wheel_cache,
+        extras=extras_override or (),
+    )

src/pip/_internal/req/req_file.py

@@ -16,6 +16,7 @@
 from pip._internal.cli import cmdoptions
 from pip._internal.download import get_file_content
 from pip._internal.exceptions import RequirementsFileParseError
+from pip._internal.req.constructors import install_req_from_editable
 from pip._internal.req.req_install import InstallRequirement
 
 __all__ = ['parse_requirements']
@@ -159,7 +160,7 @@ def process_line(line, filename, line_number, finder=None, comes_from=None,
     # yield an editable requirement
     elif opts.editables:
         isolated = options.isolated_mode if options else False
-        yield InstallRequirement.from_editable(
+        yield install_req_from_editable(
             opts.editables[0], comes_from=line_comes_from,
             constraint=constraint, isolated=isolated, wheel_cache=wheel_cache
         )

src/pip/_internal/req/req_install.py

@@ -22,9 +22,7 @@
 
 from pip._internal import wheel
 from pip._internal.build_env import NoOpBuildEnvironment
-from pip._internal.download import (
-    is_archive_file, is_url, path_to_url, url_to_path,
-)
+from pip._internal.download import is_archive_file, is_url, path_to_url
 from pip._internal.exceptions import InstallationError
 from pip._internal.locations import (
     PIP_DELETE_MARKER_FILENAME, running_under_virtualenv,
@@ -149,33 +147,6 @@ def __init__(self, req, comes_from, source_dir=None, editable=False,
 
     # Constructors
     #   TODO: Move these out of this class into custom methods.
-    @classmethod
-    def from_editable(cls, editable_req, comes_from=None, isolated=False,
-                      options=None, wheel_cache=None, constraint=False):
-        name, url, extras_override = parse_editable(editable_req)
-        if url.startswith('file:'):
-            source_dir = url_to_path(url)
-        else:
-            source_dir = None
-
-        if name is not None:
-            try:
-                req = Requirement(name)
-            except InvalidRequirement:
-                raise InstallationError("Invalid requirement: '%s'" % name)
-        else:
-            req = None
-        return cls(
-            req, comes_from, source_dir=source_dir,
-            editable=True,
-            link=Link(url),
-            constraint=constraint,
-            isolated=isolated,
-            options=options if options else {},
-            wheel_cache=wheel_cache,
-            extras=extras_override or (),
-        )
-
     @classmethod
     def from_req(cls, req, comes_from=None, isolated=False, wheel_cache=None):
         try:
@@ -1029,71 +1000,6 @@ def get_install_args(self, global_options, record_filename, root, prefix,
         return install_args
 
 
-def parse_editable(editable_req):
-    """Parses an editable requirement into:
-        - a requirement name
-        - an URL
-        - extras
-        - editable options
-    Accepted requirements:
-        svn+http://blahblah@rev#egg=Foobar[baz]&subdirectory=version_subdir
-        .[some_extra]
-    """
-
-    url = editable_req
-
-    # If a file path is specified with extras, strip off the extras.
-    url_no_extras, extras = _strip_extras(url)
-
-    if os.path.isdir(url_no_extras):
-        if not os.path.exists(os.path.join(url_no_extras, 'setup.py')):
-            raise InstallationError(
-                "Directory %r is not installable. File 'setup.py' not found." %
-                url_no_extras
-            )
-        # Treating it as code that has already been checked out
-        url_no_extras = path_to_url(url_no_extras)
-
-    if url_no_extras.lower().startswith('file:'):
-        package_name = Link(url_no_extras).egg_fragment
-        if extras:
-            return (
-                package_name,
-                url_no_extras,
-                Requirement("placeholder" + extras.lower()).extras,
-            )
-        else:
-            return package_name, url_no_extras, None
-
-    for version_control in vcs:
-        if url.lower().startswith('%s:' % version_control):
-            url = '%s+%s' % (version_control, url)
-            break
-
-    if '+' not in url:
-        raise InstallationError(
-            '%s should either be a path to a local project or a VCS url '
-            'beginning with svn+, git+, hg+, or bzr+' %
-            editable_req
-        )
-
-    vc_type = url.split('+', 1)[0].lower()
-
-    if not vcs.get_backend(vc_type):
-        error_message = 'For --editable=%s only ' % editable_req + \
-            ', '.join([backend.name + '+URL' for backend in vcs.backends]) + \
-            ' is currently supported'
-        raise InstallationError(error_message)
-
-    package_name = Link(url).egg_fragment
-    if not package_name:
-        raise InstallationError(
-            "Could not detect requirement name for '%s', please specify one "
-            "with #egg=your_package_name" % editable_req
-        )
-    return package_name, url, None
-
-
 def deduce_helpful_msg(req):
     """Returns helpful msg in case requirements file does not exist,
     or cannot be parsed.

tests/unit/test_req.py

@@ -17,8 +17,10 @@
 from pip._internal.index import PackageFinder
 from pip._internal.operations.prepare import RequirementPreparer
 from pip._internal.req import InstallRequirement, RequirementSet
+from pip._internal.req.constructors import (
+    install_req_from_editable, parse_editable,
+)
 from pip._internal.req.req_file import process_line
-from pip._internal.req.req_install import parse_editable
 from pip._internal.req.req_tracker import RequirementTracker
 from pip._internal.resolve import Resolver
 from pip._internal.utils.misc import read_text_file
@@ -85,7 +87,7 @@ def test_environment_marker_extras(self, data):
         non-wheel installs.
         """
         reqset = RequirementSet()
-        req = InstallRequirement.from_editable(
+        req = install_req_from_editable(
             data.packages.join("LocalEnvironMarker")
         )
         req.is_direct = True
@@ -398,7 +400,7 @@ def test_url_preserved_line_req(self):
     def test_url_preserved_editable_req(self):
         """Confirm the url is preserved in a editable requirement"""
         url = 'git+http://foo.com@ref#egg=foo'
-        req = InstallRequirement.from_editable(url)
+        req = install_req_from_editable(url)
         assert req.link.url == url
 
     @pytest.mark.parametrize('path', (
@@ -512,15 +514,15 @@ def test_extras_for_editable_path_requirement(self):
         url = '.[ex1,ex2]'
         filename = 'filename'
         comes_from = '-r %s (line %s)' % (filename, 1)
-        req = InstallRequirement.from_editable(url, comes_from=comes_from)
+        req = install_req_from_editable(url, comes_from=comes_from)
         assert len(req.extras) == 2
         assert req.extras == {'ex1', 'ex2'}
 
     def test_extras_for_editable_url_requirement(self):
         url = 'git+https://url#egg=SomeProject[ex1,ex2]'
         filename = 'filename'
         comes_from = '-r %s (line %s)' % (filename, 1)
-        req = InstallRequirement.from_editable(url, comes_from=comes_from)
+        req = install_req_from_editable(url, comes_from=comes_from)
         assert len(req.extras) == 2
         assert req.extras == {'ex1', 'ex2'}
 

tests/unit/test_req_file.py

@@ -12,6 +12,7 @@
     InstallationError, RequirementsFileParseError,
 )
 from pip._internal.index import PackageFinder
+from pip._internal.req.constructors import install_req_from_editable
 from pip._internal.req.req_file import (
     break_args_options, ignore_comments, join_lines, parse_requirements,
     preprocess, process_line, skip_regex,
@@ -218,15 +219,15 @@ def test_yield_editable_requirement(self):
         line = '-e %s' % url
         filename = 'filename'
         comes_from = '-r %s (line %s)' % (filename, 1)
-        req = InstallRequirement.from_editable(url, comes_from=comes_from)
+        req = install_req_from_editable(url, comes_from=comes_from)
         assert repr(list(process_line(line, filename, 1))[0]) == repr(req)
 
     def test_yield_editable_constraint(self):
         url = 'git+https://url#egg=SomeProject'
         line = '-e %s' % url
         filename = 'filename'
         comes_from = '-c %s (line %s)' % (filename, 1)
-        req = InstallRequirement.from_editable(
+        req = install_req_from_editable(
             url, comes_from=comes_from, constraint=True)
         found_req = list(process_line(line, filename, 1, constraint=True))[0]
         assert repr(found_req) == repr(req)