1 files changed, 39 insertions, 4 deletions

diff --git a/bitbake/lib/bblayers/layerindex.py b/bitbake/lib/bblayers/layerindex.py
index b2f27b21ee..ba91fac669 100644
--- a/bitbake/lib/bblayers/layerindex.py
+++ b/bitbake/lib/bblayers/layerindex.py
@@ -1,4 +1,6 @@
 #
+# Copyright BitBake Contributors
+#
 # SPDX-License-Identifier: GPL-2.0-only
 #
 
@@ -47,6 +49,31 @@ class LayerIndexPlugin(ActionPlugin):
             else:
                 logger.plain("Repository %s needs to be fetched" % url)
                 return subdir, layername, layerdir
+        elif os.path.exists(repodir) and branch:
+            """
+            If the repo is already cloned, ensure it is on the correct branch,
+            switching branches if necessary and possible.
+            """
+            base_cmd = ['git', '--git-dir=%s/.git' % repodir, '--work-tree=%s' % repodir]
+            cmd = base_cmd + ['branch']
+            completed_proc = subprocess.run(cmd, text=True, capture_output=True)
+            if completed_proc.returncode:
+                logger.error("Unable to validate repo %s (%s)" % (repodir, stderr))
+                return None, None, None
+            else:
+                if branch != completed_proc.stdout[2:-1]:
+                    cmd = base_cmd + ['status', '--short']
+                    completed_proc = subprocess.run(cmd, text=True, capture_output=True)
+                    if completed_proc.stdout.count('\n') != 0:
+                        logger.warning("There are uncommitted changes in repo %s" % repodir)
+                    cmd = base_cmd + ['checkout', branch]
+                    completed_proc = subprocess.run(cmd, text=True, capture_output=True)
+                    if completed_proc.returncode:
+                        # Could be due to original shallow clone on a different branch for example
+                        logger.error("Unable to automatically switch %s to desired branch '%s' (%s)"
+                                     % (repodir, branch, completed_proc.stderr))
+                        return None, None, None
+            return subdir, layername, layerdir
         elif os.path.exists(layerdir):
             return subdir, layername, layerdir
         else:
@@ -159,12 +186,17 @@ class LayerIndexPlugin(ActionPlugin):
                 logger.plain('  recommended by: %s' % ' '.join(recommendedby))
 
         if dependencies:
-            fetchdir = self.tinfoil.config_data.getVar('BBLAYERS_FETCH_DIR')
-            if not fetchdir:
-                logger.error("Cannot get BBLAYERS_FETCH_DIR")
-                return 1
+            if args.fetchdir:
+                fetchdir = args.fetchdir
+            else:
+                fetchdir = self.tinfoil.config_data.getVar('BBLAYERS_FETCH_DIR')
+                if not fetchdir:
+                    logger.error("Cannot get BBLAYERS_FETCH_DIR")
+                    return 1
+
             if not os.path.exists(fetchdir):
                 os.makedirs(fetchdir)
+
             addlayers = []
 
             for deplayerbranch in dependencies:
@@ -206,6 +238,8 @@ class LayerIndexPlugin(ActionPlugin):
 """
         args.show_only = True
         args.ignore = []
+        args.fetchdir = ""
+        args.shallow = True
         self.do_layerindex_fetch(args)
 
     def register_commands(self, sp):
@@ -214,6 +248,7 @@ class LayerIndexPlugin(ActionPlugin):
         parser_layerindex_fetch.add_argument('-b', '--branch', help='branch name to fetch')
         parser_layerindex_fetch.add_argument('-s', '--shallow', help='do only shallow clones (--depth=1)', action='store_true')
         parser_layerindex_fetch.add_argument('-i', '--ignore', help='assume the specified layers do not need to be fetched/added (separate multiple layers with commas, no spaces)', metavar='LAYER')
+        parser_layerindex_fetch.add_argument('-f', '--fetchdir', help='directory to fetch the layer(s) into (will be created if it does not exist)')
         parser_layerindex_fetch.add_argument('layername', nargs='+', help='layer to fetch')
 
         parser_layerindex_show_depends = self.add_command(sp, 'layerindex-show-depends', self.do_layerindex_show_depends, parserecipes=False)