init: add --manifest-upstream-branch

When a sha1 is provided to '--manifest-branch', the ref which
is expected to contain that sha1 can be provided using the new
'--manifest-upstream-branch' option. This is useful with
'--current-branch' to avoid having to sync all heads and tags,
or with a commit that comes from a non-head/tag ref (like a
Gerrit change ref).

Change-Id: I46a3e255ca69ed9e809039e58b0c163e02af94ef
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/436717
Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Commit-Queue: Kaushik Lingarkar <kaushik.lingarkar@linaro.org>
Tested-by: Kaushik Lingarkar <kaushik.lingarkar@linaro.org>

man/repo-init.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man.
-.TH REPO "1" "October 2022" "repo init" "Repo Manual"
+.TH REPO "1" "September 2024" "repo init" "Repo Manual"
 .SH NAME
 repo \- repo init - manual page for repo init
 .SH SYNOPSIS
@@ -28,6 +28,11 @@ manifest repository location
 \fB\-b\fR REVISION, \fB\-\-manifest\-branch\fR=\fI\,REVISION\/\fR
 manifest branch or revision (use HEAD for default)
 .TP
+\fB\-\-manifest\-upstream\-branch\fR=\fI\,BRANCH\/\fR
+when a commit is provided to \fB\-\-manifest\-branch\fR, this
+is the name of the git ref in which the commit can be
+found
+.TP
 \fB\-m\fR NAME.xml, \fB\-\-manifest\-name\fR=\fI\,NAME\/\fR.xml
 initial manifest file
 .TP
@@ -163,6 +168,10 @@ The optional \fB\-b\fR argument can be used to select the manifest branch to che
 and use. If no branch is specified, the remote's default branch is used. This is
 equivalent to using \fB\-b\fR HEAD.
 .PP
+The optional \fB\-\-manifest\-upstream\-branch\fR argument can be used when a commit is
+provided to \fB\-\-manifest\-branch\fR (or \fB\-b\fR), to specify the name of the git ref in
+which the commit can be found.
+.PP
 The optional \fB\-m\fR argument can be used to specify an alternate manifest to be
 used. If no manifest is specified, the manifest default.xml will be used.
 .PP

repo

@@ -124,7 +124,7 @@ if not REPO_REV:
 BUG_URL = "https://issues.gerritcodereview.com/issues/new?component=1370071"
 
 # increment this whenever we make important changes to this script
-VERSION = (2, 45)
+VERSION = (2, 48)
 
 # increment this if the MAINTAINER_KEYS block is modified
 KEYRING_VERSION = (2, 3)
@@ -282,6 +282,12 @@ def InitParser(parser):
         metavar="REVISION",
         help="manifest branch or revision (use HEAD for default)",
     )
+    group.add_option(
+        "--manifest-upstream-branch",
+        help="when a commit is provided to --manifest-branch, this "
+        "is the name of the git ref in which the commit can be found",
+        metavar="BRANCH",
+    )
     group.add_option(
         "-m",
         "--manifest-name",

subcmds/init.py

@@ -52,6 +52,10 @@ class Init(InteractiveCommand, MirrorSafeCommand):
 to checkout and use.  If no branch is specified, the remote's default
 branch is used.  This is equivalent to using -b HEAD.
 
+The optional --manifest-upstream-branch argument can be used when a commit is
+provided to --manifest-branch (or -b), to specify the name of the git ref in
+which the commit can be found.
+
 The optional -m argument can be used to specify an alternate manifest
 to be used. If no manifest is specified, the manifest default.xml
 will be used.
@@ -135,6 +139,7 @@ def _SyncManifest(self, opt):
         # manifest project is special and is created when instantiating the
         # manifest which happens before we parse options.
         self.manifest.manifestProject.clone_depth = opt.manifest_depth
+        self.manifest.manifestProject.upstream = opt.manifest_upstream_branch
         clone_filter_for_depth = (
             "blob:none" if (_REPO_ALLOW_SHALLOW == "0") else None
         )
@@ -317,6 +322,12 @@ def ValidateOptions(self, opt, args):
                 " be used with --standalone-manifest."
             )
 
+        if opt.manifest_upstream_branch and opt.manifest_branch is None:
+            self.OptionParser.error(
+                "--manifest-upstream-branch cannot be used without "
+                "--manifest-branch."
+            )
+
         if args:
             if opt.manifest_url:
                 self.OptionParser.error(