1 files changed, 41 insertions, 3 deletions

diff --git a/bitbake/lib/bb/fetch2/git.py b/bitbake/lib/bb/fetch2/git.py
index b97967b487..b59a7cdc84 100644
--- a/bitbake/lib/bb/fetch2/git.py
+++ b/bitbake/lib/bb/fetch2/git.py
@@ -379,6 +379,35 @@ class Git(FetchMethod):
             if missing_rev:
                 raise bb.fetch2.FetchError("Unable to find revision %s even from upstream" % missing_rev)
 
+        if self._contains_lfs(ud, d, ud.clonedir) and self._need_lfs(ud):
+            # Unpack temporary working copy, use it to run 'git checkout' to force pre-fetching
+            # of all LFS blobs needed at the the srcrev.
+            #
+            # It would be nice to just do this inline here by running 'git-lfs fetch'
+            # on the bare clonedir, but that operation requires a working copy on some
+            # releases of Git LFS.
+            tmpdir = tempfile.mkdtemp(dir=d.getVar('DL_DIR'))
+            try:
+                # Do the checkout. This implicitly involves a Git LFS fetch.
+                self.unpack(ud, tmpdir, d)
+
+                # Scoop up a copy of any stuff that Git LFS downloaded. Merge them into
+                # the bare clonedir.
+                #
+                # As this procedure is invoked repeatedly on incremental fetches as
+                # a recipe's SRCREV is bumped throughout its lifetime, this will
+                # result in a gradual accumulation of LFS blobs in <ud.clonedir>/lfs
+                # corresponding to all the blobs reachable from the different revs
+                # fetched across time.
+                #
+                # Only do this if the unpack resulted in a .git/lfs directory being
+                # created; this only happens if at least one blob needed to be
+                # downloaded.
+                if os.path.exists(os.path.join(tmpdir, "git", ".git", "lfs")):
+                    runfetchcmd("tar -cf - lfs | tar -xf - -C %s" % ud.clonedir, d, workdir="%s/git/.git" % tmpdir)
+            finally:
+                bb.utils.remove(tmpdir, recurse=True)
+
     def build_mirror_data(self, ud, d):
         if ud.shallow and ud.write_shallow_tarballs:
             if not os.path.exists(ud.fullshallow):
@@ -474,7 +503,7 @@ class Git(FetchMethod):
         if os.path.exists(destdir):
             bb.utils.prunedir(destdir)
 
-        need_lfs = ud.parm.get("lfs", "1") == "1"
+        need_lfs = self._need_lfs(ud)
 
         if not need_lfs:
             ud.basecmd = "GIT_LFS_SKIP_SMUDGE=1 " + ud.basecmd
@@ -563,6 +592,9 @@ class Git(FetchMethod):
             raise bb.fetch2.FetchError("The command '%s' gave output with more then 1 line unexpectedly, output: '%s'" % (cmd, output))
         return output.split()[0] != "0"
 
+    def _need_lfs(self, ud):
+        return ud.parm.get("lfs", "1") == "1"
+
     def _contains_lfs(self, ud, d, wd):
         """
         Check if the repository has 'lfs' (large file) content
@@ -573,8 +605,14 @@ class Git(FetchMethod):
         else:
             branchname = "master"
 
-        cmd = "%s grep lfs origin/%s:.gitattributes | wc -l" % (
-            ud.basecmd, ud.branches[ud.names[0]])
+        # The bare clonedir doesn't use the remote names; it has the branch immediately.
+        if wd == ud.clonedir:
+            refname = ud.branches[ud.names[0]]
+        else:
+            refname = "origin/%s" % ud.branches[ud.names[0]]
+
+        cmd = "%s grep lfs %s:.gitattributes | wc -l" % (
+            ud.basecmd, refname)
 
         try:
             output = runfetchcmd(cmd, d, quiet=True, workdir=wd)