repo: lower min version of git a bit

We were perhaps a bit too hasty to jump to git-2.10.  Existing LTS
releases of Ubuntu are quite old still: Trusty has 1.9 while Xenial
has 2.5.  While we plan on dropping support for those eventually as
we migrate to Python 3.6, we don't need to be so strict just yet on
the git versions.

We also want to disconnect the version the repo launcher requires
from the version the rest of the source tree requires.  The repo
launcher doesn't need as many features, and being flexible there
allows us more freedom to upgrade & rollback as needed.

So we'll allow git-1.7 again, but start warning on any users older
than git-1.9.  This aligns better with existing LTS releases, and
gives users a chance to start upgrading before we cut them off.

Change-Id: I140305dd8e42c9719c84e2aee0dc6a5c5b18da25
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254573
Reviewed-by: David Pursehouse <dpursehouse@collab.net>
Tested-by: Mike Frysinger <vapier@google.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/subcmds/init.py b/subcmds/init.py
index 6594a602..a7950069 100644
--- a/subcmds/init.py
+++ b/subcmds/init.py
@@ -34,7 +34,7 @@ from command import InteractiveCommand, MirrorSafeCommand
 from error import ManifestParseError
 from project import SyncBuffer
 from git_config import GitConfig
-from git_command import git_require, MIN_GIT_VERSION
+from git_command import git_require, MIN_GIT_VERSION_SOFT, MIN_GIT_VERSION_HARD
 import platform_utils
 
 class Init(InteractiveCommand, MirrorSafeCommand):
@@ -451,7 +451,12 @@ to update the working directory files.
       self.OptionParser.error('--mirror and --archive cannot be used together.')
 
   def Execute(self, opt, args):
-    git_require(MIN_GIT_VERSION, fail=True)
+    git_require(MIN_GIT_VERSION_HARD, fail=True)
+    if not git_require(MIN_GIT_VERSION_SOFT):
+      print('repo: warning: git-%s+ will soon be required; please upgrade your '
+            'version of git to maintain support.'
+            % ('.'.join(str(x) for x in MIN_GIT_VERSION_SOFT),),
+            file=sys.stderr)
 
     self._SyncManifest(opt)
     self._LinkManifest(opt.manifest_name)