[bitbake-devel] fetch2/git: Tweak git fetcher to handling repo updates correctly

[Richard Purdie]

Currently the git fetcher can malfunction when branches change in remote
repositories since whilst the update code updates the "origin" remote,
this isn't linked to the local heads.

By passing the --mirror option to 'git clone' and 'git remote add',
linkage between the local heads and remote heads is created with a 1:1
mapping, hence all the appropriate heads are then updated correctly.

This fixes some issues which have been seen with the Yocto autobuilder
mirrors.

Signed-off-by: Richard Purdie <richard.purdie at linux-foundation.org>

diff --git a/bitbake/lib/bb/fetch2/git.py b/bitbake/lib/bb/fetch2/git.py
index f3bc793..7954f66 100644
--- a/bitbake/lib/bb/fetch2/git.py
+++ b/bitbake/lib/bb/fetch2/git.py
@@ -170,7 +170,7 @@ class Git(FetchMethod):
 
         # If the repo still doesn't exist, fallback to cloning it
         if not os.path.exists(ud.clonedir):
-            clone_cmd = "%s clone --bare %s://%s%s%s %s" % \
+            clone_cmd = "%s clone --bare --mirror %s://%s%s%s %s" % \
                   (ud.basecmd, ud.proto, username, ud.host, ud.path, ud.clonedir)
             bb.fetch2.check_network_access(d, clone_cmd)
             runfetchcmd(clone_cmd, d)
@@ -188,7 +188,7 @@ class Git(FetchMethod):
             except bb.fetch2.FetchError:
                 logger.debug(1, "No Origin")
             
-            runfetchcmd("%s remote add origin %s://%s%s%s" % (ud.basecmd, ud.proto, username, ud.host, ud.path), d)
+            runfetchcmd("%s remote add --mirror origin %s://%s%s%s" % (ud.basecmd, ud.proto, username, ud.host, ud.path), d)
             fetch_cmd = "%s fetch --all -t" % ud.basecmd
             bb.fetch2.check_network_access(d, fetch_cmd, ud.url)
             runfetchcmd(fetch_cmd, d)