Harmonize type signature of VersionControl.get_remote_url() subclasses

In the base class, the signature is defined as:

    type: (str) -> str

Further, the docstring says:

    Raises RemoteNotFoundError if the repository does not have a remote
    url configured.

However, some subclasses were returning None instead of raising
RemoteNotFoundError. This violated the type signature and forced calling
code to handle multiple error paradigms.

Now, all subclasses implement the base's signature.

This allowed simplifying some call sites as they can assume None will
not be returned.

This mismatch was noticed while trying to remove "mypy:
disallow-untyped-defs=False" comments.

src/pip/_internal/operations/freeze.py

@@ -225,8 +225,7 @@ def get_requirement_info(dist):
             "falling back to uneditable format", exc
         )
     else:
-        if req is not None:
-            return (req, True, [])
+        return (req, True, [])
 
     logger.warning(
         'Could not determine repository location of %s', location

src/pip/_internal/vcs/bazaar.py

@@ -9,7 +9,7 @@ from pip._internal.utils.misc import display_path, rmtree
 from pip._internal.utils.subprocess import make_command
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 from pip._internal.utils.urls import path_to_url
-from pip._internal.vcs.versioncontrol import VersionControl, vcs
+from pip._internal.vcs.versioncontrol import RemoteNotFoundError, VersionControl, vcs
 
 if MYPY_CHECK_RUNNING:
     from typing import Optional, Tuple
@@ -89,6 +89,7 @@ class Bazaar(VersionControl):
 
     @classmethod
     def get_remote_url(cls, location):
+        # type: (str) -> str
         urls = cls.run_command(['info'], cwd=location)
         for line in urls.splitlines():
             line = line.strip()
@@ -99,7 +100,7 @@ class Bazaar(VersionControl):
                     if cls._is_local_repository(repo):
                         return path_to_url(repo)
                     return repo
-        return None
+        raise RemoteNotFoundError
 
     @classmethod
     def get_revision(cls, location):

src/pip/_internal/vcs/git.py

@@ -303,6 +303,7 @@ class Git(VersionControl):
 
     @classmethod
     def get_remote_url(cls, location):
+        # type: (str) -> str
         """
         Return URL of the first remote encountered.
 

src/pip/_internal/vcs/mercurial.py

@@ -87,6 +87,7 @@ class Mercurial(VersionControl):
 
     @classmethod
     def get_remote_url(cls, location):
+        # type: (str) -> str
         url = cls.run_command(
             ['showconfig', 'paths.default'],
             cwd=location).strip()

src/pip/_internal/vcs/subversion.py

@@ -14,7 +14,7 @@ from pip._internal.utils.misc import (
 )
 from pip._internal.utils.subprocess import make_command
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING
-from pip._internal.vcs.versioncontrol import VersionControl, vcs
+from pip._internal.vcs.versioncontrol import RemoteNotFoundError, VersionControl, vcs
 
 _svn_xml_url_re = re.compile('url="([^"]+)"')
 _svn_rev_re = re.compile(r'committed-rev="(\d+)"')
@@ -110,6 +110,7 @@ class Subversion(VersionControl):
 
     @classmethod
     def get_remote_url(cls, location):
+        # type: (str) -> str
         # In cases where the source is in a subdirectory, not alongside
         # setup.py we have to look up in the location until we find a real
         # setup.py
@@ -125,7 +126,7 @@ class Subversion(VersionControl):
                     "parent directories)",
                     orig_location,
                 )
-                return None
+                raise RemoteNotFoundError
 
         return cls._get_svn_url_rev(location)[0]
 

src/pip/_internal/vcs/versioncontrol.py

@@ -410,7 +410,7 @@ class VersionControl(object):
 
     @classmethod
     def get_src_requirement(cls, repo_dir, project_name):
-        # type: (str, str) -> Optional[str]
+        # type: (str, str) -> str
         """
         Return the requirement string to use to redownload the files
         currently at the given repository directory.
@@ -423,8 +423,6 @@ class VersionControl(object):
             {repository_url}@{revision}#egg={project_name}
         """
         repo_url = cls.get_remote_url(repo_dir)
-        if repo_url is None:
-            return None
 
         if cls.should_add_vcs_url_prefix(repo_url):
             repo_url = '{}+{}'.format(cls.name, repo_url)

tests/functional/test_vcs_bazaar.py

@@ -8,6 +8,7 @@ import pytest
 
 from pip._internal.utils.misc import hide_url
 from pip._internal.vcs.bazaar import Bazaar
+from pip._internal.vcs.versioncontrol import RemoteNotFoundError
 from tests.lib import (
     _test_path_to_file_url,
     _vcs_add,
@@ -65,3 +66,15 @@ def test_export_rev(script, tmpdir):
 
     with open(export_dir / 'test_file', 'r') as f:
         assert f.read() == 'something initial'
+
+
+@need_bzr
+def test_get_remote_url__no_remote(script, tmpdir):
+    repo_dir = tmpdir / 'temp-repo'
+    repo_dir.mkdir()
+    repo_dir = str(repo_dir)
+
+    script.run('bzr', 'init', repo_dir)
+
+    with pytest.raises(RemoteNotFoundError):
+        Bazaar().get_remote_url(repo_dir)

tests/functional/test_vcs_subversion.py

@@ -0,0 +1,17 @@
+import pytest
+
+from pip._internal.vcs.subversion import Subversion
+from pip._internal.vcs.versioncontrol import RemoteNotFoundError
+from tests.lib import _create_svn_repo, need_svn
+
+
+@need_svn
+def test_get_remote_url__no_remote(script, tmpdir):
+    repo_dir = tmpdir / 'temp-repo'
+    repo_dir.mkdir()
+    repo_dir = str(repo_dir)
+
+    _create_svn_repo(script, repo_dir)
+
+    with pytest.raises(RemoteNotFoundError):
+        Subversion().get_remote_url(repo_dir)