git-new-workdir: don't fail if the target directory is empty

Allow new workdirs to be created in an empty directory (similar to "git
clone").  Provide more error checking and clean up on failure.

Signed-off-by: Paul Smith <paul@mad-scientist.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/contrib/workdir/git-new-workdir b/contrib/workdir/git-new-workdir
index 75e8b258177f7f04dadcac125f2bf7ebea4d0f81..888c34a5215258ad7d5715771f92ab58f3efd363 100755 (executable)
--- a/contrib/workdir/git-new-workdir
+++ b/contrib/workdir/git-new-workdir
@@ -10,6 +10,10 @@ die () {
        exit 128
 }
 
+failed () {
+       die "unable to create new workdir '$new_workdir'!"
+}
+
 if test $# -lt 2 || test $# -gt 3
 then
        usage "$0 <repository> <new_workdir> [<branch>]"
@@ -35,7 +39,7 @@ esac
 
 # don't link to a configured bare repository
 isbare=$(git --git-dir="$git_dir" config --bool --get core.bare)
-if test ztrue = z$isbare
+if test ztrue = "z$isbare"
 then
        die "\"$git_dir\" has core.bare set to true," \
                " remove from \"$git_dir/config\" to use $0"
@@ -48,35 +52,54 @@ then
                "a complete repository."
 fi
 
-# don't recreate a workdir over an existing repository
-if test -e "$new_workdir"
+# make sure the links in the workdir have full paths to the original repo
+git_dir=$(cd "$git_dir" && pwd) || exit 1
+
+# don't recreate a workdir over an existing directory, unless it's empty
+if test -d "$new_workdir"
 then
-       die "destination directory '$new_workdir' already exists."
+       if test $(ls -a1 "$new_workdir/." | wc -l) -ne 2
+       then
+               die "destination directory '$new_workdir' is not empty."
+       fi
+       cleandir="$new_workdir/.git"
+else
+       cleandir="$new_workdir"
 fi
 
-# make sure the links use full paths
-git_dir=$(cd "$git_dir"; pwd)
+mkdir -p "$new_workdir/.git" || failed
+cleandir=$(cd "$cleandir" && pwd) || failed
 
-# create the workdir
-mkdir -p "$new_workdir/.git" || die "unable to create \"$new_workdir\"!"
+cleanup () {
+       rm -rf "$cleandir"
+}
+siglist="0 1 2 15"
+trap cleanup $siglist
 
 # create the links to the original repo.  explicitly exclude index, HEAD and
 # logs/HEAD from the list since they are purely related to the current working
 # directory, and should not be shared.
 for x in config refs logs/refs objects info hooks packed-refs remotes rr-cache svn
 do
+       # create a containing directory if needed
        case $x in
        */*)
-               mkdir -p "$(dirname "$new_workdir/.git/$x")"
+               mkdir -p "$new_workdir/.git/${x%/*}"
                ;;
        esac
-       ln -s "$git_dir/$x" "$new_workdir/.git/$x"
+
+       ln -s "$git_dir/$x" "$new_workdir/.git/$x" || failed
 done
 
-# now setup the workdir
-cd "$new_workdir"
+# commands below this are run in the context of the new workdir
+cd "$new_workdir" || failed
+
 # copy the HEAD from the original repository as a default branch
-cp "$git_dir/HEAD" .git/HEAD
-# checkout the branch (either the same as HEAD from the original repository, or
-# the one that was asked for)
+cp "$git_dir/HEAD" .git/HEAD || failed
+
+# the workdir is set up.  if the checkout fails, the user can fix it.
+trap - $siglist
+
+# checkout the branch (either the same as HEAD from the original repository,
+# or the one that was asked for)
 git checkout -f $branch