Add --closest option to git-lkgr.

git-lkgr

 #!/bin/bash
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 branch_name=""
 checkout_branch=no
 create_branch=no
 quiet=no
 svn_lkgr=
 
 while [ $# -gt 0 ]; do
   case "$1" in
     --checkout|--force-branch)
       checkout_branch=yes
       create_branch=yes
       ;;
+    --closest)
+      use_closest=yes
+      ;;
     --create)
       create_branch=yes
       ;;
     -n|--name)
       branch_name=$2
       create_branch=yes
       shift
       ;;
     -q|--quiet)
       quiet=yes
       ;;
     -r|--revision)
       svn_lkgr="$2"
       shift
       ;;
     *)
       echo "Unknown option: $1"
       echo "Usage:"
       echo "  --checkout         Create a branch and check it out."
       echo "  --create           Create a branch."
+      echo "  --closest          Use closest git commit to the target svn revision."
+      echo "                       Otherwise --checkout may be required to create"
+      echo "                       a git commit for a specific svn revision."
       echo "  -n, --name <name>  Specify the name of branch to create or reset."
       echo "                       This will force the branch using 'git branch -f '."
       echo "  -q, --quiet        Quiet."
       echo "  -r, --revision <r> Svn revision number use instead of server provided lkgr."
       exit 1
       ;;
   esac
   shift
 done
 
@@ skipping 39 matching lines @@
   closest_commit=
   closest_svn_commit=
 else
   closest_svn_commit=`git rev-list -n 1 ${closest_commit}^1`
   if [ $? != 0 -o -z "$closest_svn_commit" ]; then
     cat <<EOF 1>&2
   I am thoroughly confused.  Please file a bug report at http://new.crbug.com.
 EOF
     exit 1
   fi
+  closest_svn=`git svn find-rev ${closest_svn_commit}`
+fi
+
+if [ "${use_closest}" = "yes" ]; then
+  svn_lkgr="${closest_svn}"
+  git_lkgr="${closest_svn_commit}"
 fi
 
 # Determine lkgr_branch:
 if [ "${branch_name}" != "" ]; then
   # Use the provided name for the branch.
   lkgr_branch="${branch_name}"
 
   # If the branch already exists, force the update to it.
   git rev-parse --verify -q "${branch_name}" >/dev/null
   if [ $? -eq 0 ]; then
@@ skipping 21 matching lines @@
     git branch ${force_branch} "${lkgr_branch}" "${closest_commit}" || exit 1
   fi
   if [ "$checkout_branch" = "yes" ]; then
     git checkout "${lkgr_branch}"
   fi
   exit 0
 elif [ "${quiet}" = "yes" ]; then
   exit 1
 elif [ "${checkout_branch}" = "no" ]; then
   echo "There is no master commit which corresponds exactly to svn revision ${svn_lkgr}."
+  echo "Call 'git lkgr --checkout' to create a branch with a commit to match ${svn_lkgr}."
   if [ -n "$closest_commit" ]; then
-    echo "The closest commit is ${closest_commit}."
+    echo "The closest commit is r${closest_svn}, ${closest_commit}."
+    echo "Use the --closest option to use the closest instead of the target revision."
   fi
-  echo "Call 'git lkgr --checkout' to create a branch with a commit to match ${svn_lkgr}."
   exit 0
 fi
 
 current_head=`git branch | grep '^\*' | cut -c3-`
 if [ "${current_head}" = "(no branch)" ]; then
   current_head=`git rev-parse HEAD`
 fi
 
 git checkout --detach "${git_lkgr}" &&
 python tools/deps2git/deps2git.py -d DEPS -o .DEPS.git -w .. &&
@@ skipping 33 matching lines @@
 To create a working branch, do this:
 
 \$ git branch --track my_new_branch $lkgr_branch
 
 'git-cl upload' will do the right thing, i.e., it will cherry-pick all
 your changes from my_new_branch, but *not* the .DEPS.git+.gitmodules+submodules
 commit on $lkgr_branch.
 --------------------------------------------------------------------------------
 
 EOF