Shallow clone from git. Resolve #2432.

pip/vcs/git.py

@@ -9,6 +9,7 @@
 from pip._vendor.six.moves.urllib import parse as urllib_parse
 from pip._vendor.six.moves.urllib import request as urllib_request
 
+from pip.exceptions import InstallationError
 from pip.utils import display_path, rmtree
 from pip.vcs import vcs, VersionControl
 
@@ -115,13 +116,21 @@ def obtain(self, dest):
             rev_options = [rev]
             rev_display = ' (to %s)' % rev
         else:
+            rev = 'master'
             rev_options = ['origin/master']
             rev_display = ''
         if self.check_destination(dest, url, rev_options, rev_display):
             logger.info(
                 'Cloning %s%s to %s', url, rev_display, display_path(dest),
             )
-            self.run_command(['clone', '-q', url, dest])
+            try:
+                self.run_command([
+                    'clone', '-q', '--branch', rev, '--depth', '1', url, dest])
+            except InstallationError as e:
+                if '128' in str(e):  # commit sha's can't be shallow cloned
+                    self.run_command(['clone', '-q', url, dest])
+                else:
+                    raise
 
             if rev:
                 rev_options = self.check_rev_options(rev, dest, rev_options)
@@ -253,10 +262,15 @@ def get_url_rev(self):
     def update_submodules(self, location):
         if not os.path.exists(os.path.join(location, '.gitmodules')):
             return
-        self.run_command(
-            ['submodule', 'update', '--init', '--recursive', '-q'],
-            cwd=location,
-        )
+        cmd = ['submodule', 'update', '--init', '--recursive', '-q']
+        try:
+            self.run_command(cmd + ['--depth', '1'], cwd=location)
+        except InstallationError as e:
+            if '128' in str(e):  # commit sha's can't be shallow cloned
+                self.run_command(cmd, cwd=location)
+            else:
+                raise
+
 
     @classmethod
     def controls_location(cls, location):

tests/functional/test_install_vcs.py

@@ -30,7 +30,8 @@ def test_install_noneditable_git(script, tmpdir):
     result = script.pip(
         'install',
         'git+https://github.com/pypa/pip-test-package.git'
-        '@0.1.1#egg=pip-test-package'
+        '@0.1.1#egg=pip-test-package',
+        expect_stderr=True
     )
     egg_info_folder = (
         script.site_packages /
@@ -97,7 +98,8 @@ def test_git_with_tag_name_as_revision(script):
     _change_test_package_version(script, version_pkg_path)
     script.pip(
         'install', '-e', '%s@test_tag#egg=version_pkg' %
-        ('git+file://' + version_pkg_path.abspath.replace('\\', '/'))
+        ('git+file://' + version_pkg_path.abspath.replace('\\', '/')),
+        expect_stderr=True
     )
     version = script.run('version_pkg')
     assert '0.1' in version.stdout
@@ -211,7 +213,7 @@ def test_git_with_ambiguous_revs(script):
         (version_pkg_path.abspath.replace('\\', '/'))
     )
     script.run('git', 'tag', '0.1', cwd=version_pkg_path)
-    result = script.pip('install', '-e', package_url)
+    result = script.pip('install', '-e', package_url, expect_stderr=True)
     assert 'Could not find a tag or branch' not in result.stdout
     # it is 'version-pkg' instead of 'version_pkg' because
     # egg-link name is version-pkg.egg-link because it is a single .py module

tests/functional/test_install_vcs_git.py

@@ -112,7 +112,8 @@ def test_check_submodule_addition(script):
     module_path, submodule_path = _create_test_package_with_submodule(script)
 
     install_result = script.pip(
-        'install', '-e', 'git+' + module_path + '#egg=version_pkg'
+        'install', '-e', 'git+' + module_path + '#egg=version_pkg',
+        expect_stderr=True
     )
     assert (
         script.venv / 'src/version-pkg/testpkg/static/testfile'
@@ -133,3 +134,23 @@ def test_check_submodule_addition(script):
         script.venv / 'src/version-pkg/testpkg/static/testfile2'
         in update_result.files_created
     )
+
+
+@pytest.mark.network
+def test_shallow_clone(script):
+    """
+    Installing from a tag rev should be shallow.
+    """
+    src = script.venv_path + '/src/' + 'pip-test-package'
+
+    script.pip(
+        'install', '-e', 'git+https://github.com/pypa/pip-test-package.git' +
+        '@0.1.1#egg=pip-test-package', expect_stderr=True
+    )
+
+    tag = script.run('git', 'describe', '--tags', cwd=src).stdout.strip('\n')
+    assert tag == '0.1.1'
+
+    depth = script.run(
+        'git', 'rev-list', 'HEAD', '--count', cwd=src).stdout.strip('\n')
+    assert depth == '1'