fix #533 . quite and recursive on submodule checkout

pip/vcs/git.py

 import tempfile
 import re
+import os.path
 from pip.util import call_subprocess
 from pip.util import display_path, rmtree
 from pip.vcs import vcs, VersionControl
@@ -86,6 +87,8 @@ class Git(VersionControl):
         call_subprocess(
             [self.cmd, 'checkout', '-q'] + rev_options, cwd=dest)
 
+        self.update_submodules(dest)
+
     def update(self, dest, rev_options):
         # First fetch changes from the default remote
         call_subprocess([self.cmd, 'fetch', '-q'], cwd=dest)
@@ -93,6 +96,8 @@ class Git(VersionControl):
         if rev_options:
             rev_options = self.check_rev_options(rev_options[0], dest, rev_options)
         call_subprocess([self.cmd, 'reset', '--hard', '-q'] + rev_options, cwd=dest)
+        #: update submodules
+        self.update_submodules(dest)
 
     def obtain(self, dest):
         url, rev = self.get_url_rev()
@@ -106,8 +111,7 @@ class Git(VersionControl):
             logger.notify('Cloning %s%s to %s' % (url, rev_display, display_path(dest)))
             call_subprocess([self.cmd, 'clone', '-q', url, dest])
             #: repo may contain submodules
-            call_subprocess([self.cmd, 'submodule', 'init'], cwd=dest)
-            call_subprocess([self.cmd, 'submodule', 'update'], cwd=dest)
+            self.update_submodules(dest)
             if rev:
                 rev_options = self.check_rev_options(rev, dest, rev_options)
                 # Only do a checkout if rev_options differs from HEAD
@@ -207,5 +211,11 @@ class Git(VersionControl):
         return call_subprocess([self.cmd, 'rev-parse', name],
                                show_stdout=False, cwd=location)
 
+    def update_submodules(self, location):
+        if not os.path.exists(os.path.join(location, '.gitmodules')):
+            return
+        call_subprocess([self.cmd, 'submodule', 'init', '-q'], cwd=location)
+        call_subprocess([self.cmd, 'submodule', 'update', '--recursive', '-q'],
+                        cwd=location)
 
 vcs.register(Git)