X-Git-Url: https://git.octo.it/?p=git.git;a=blobdiff_plain;f=git-checkout.sh;h=564117f0064aba32e190a49106eaecfdb422b31e;hp=3bbd1117739b02572aece86030bb9f02f3110d34;hb=HEAD;hpb=2ed7542fad01558306b6187e3b19c64243234349

diff --git a/git-checkout.sh b/git-checkout.sh
index 3bbd1117..564117f0 100755
--- a/git-checkout.sh
+++ b/git-checkout.sh
@@ -1,14 +1,18 @@
 #!/bin/sh
 
-USAGE='[-f] [-b <new_branch>] [<branch>] [<paths>...]'
+USAGE='[-f] [-b <new_branch>] [-m] [<branch>] [<paths>...]'
 SUBDIRECTORY_OK=Sometimes
 . git-sh-setup
 
 old=$(git-rev-parse HEAD)
+old_name=HEAD
 new=
+new_name=
 force=
 branch=
 newbranch=
+newbranch_log=
+merge=
 while [ "$#" != "0" ]; do
     arg="$1"
     shift
@@ -21,11 +25,17 @@ while [ "$#" != "0" ]; do
 		[ -e "$GIT_DIR/refs/heads/$newbranch" ] &&
 			die "git checkout: branch $newbranch already exists"
 		git-check-ref-format "heads/$newbranch" ||
-			die "we do not like '$newbranch' as a branch name."
+			die "git checkout: we do not like '$newbranch' as a branch name."
+		;;
+	"-l")
+		newbranch_log=1
 		;;
 	"-f")
 		force=1
 		;;
+	-m)
+		merge=1
+		;;
 	--)
 		break
 		;;
@@ -40,6 +50,7 @@ while [ "$#" != "0" ]; do
 				exit 1
 			fi
 			new="$rev"
+			new_name="$arg^0"
 			if [ -f "$GIT_DIR/refs/heads/$arg" ]; then
 				branch="$arg"
 			fi
@@ -47,9 +58,11 @@ while [ "$#" != "0" ]; do
 		then
 			# checking out selected paths from a tree-ish.
 			new="$rev"
+			new_name="$arg^{tree}"
 			branch=
 		else
 			new=
+			new_name=
 			branch=
 			set x "$arg" "$@"
 			shift
@@ -71,9 +84,15 @@ done
 
 if test "$#" -ge 1
 then
-	if test '' != "$newbranch$force"
+	hint=
+	if test "$#" -eq 1
+	then
+		hint="
+Did you intend to checkout '$@' which can not be resolved as commit?"
+	fi
+	if test '' != "$newbranch$force$merge"
 	then
-		die "updating paths and switching branches or forcing are incompatible."
+		die "git checkout: updating paths is incompatible with switching branches/forcing$hint"
 	fi
 	if test '' != "$new"
 	then
@@ -104,7 +123,7 @@ then
 	cd "$cdup"
 fi
 
-[ -z "$new" ] && new=$old
+[ -z "$new" ] && new=$old && new_name="$old_name"
 
 # If we don't have an old branch that we're switching to,
 # and we don't have a new branch name for the target we
@@ -113,7 +132,8 @@ fi
 
 [ -z "$branch$newbranch" ] &&
 	[ "$new" != "$old" ] &&
-	die "git checkout: you need to specify a new branch name"
+	die "git checkout: to checkout the requested commit you need to specify 
+              a name for a new branch which is created and switched to"
 
 if [ "$force" ]
 then
@@ -121,7 +141,51 @@ then
 	git-checkout-index -q -f -u -a
 else
     git-update-index --refresh >/dev/null
-    git-read-tree -m -u $old $new
+    merge_error=$(git-read-tree -m -u $old $new 2>&1) || (
+	case "$merge" in
+	'')
+		echo >&2 "$merge_error"
+		exit 1 ;;
+	esac
+
+	# Match the index to the working tree, and do a three-way.
+    	git diff-files --name-only | git update-index --remove --stdin &&
+	work=`git write-tree` &&
+	git read-tree --reset $new &&
+	git checkout-index -f -u -q -a &&
+	git read-tree -m -u --aggressive $old $new $work || exit
+
+	if result=`git write-tree 2>/dev/null`
+	then
+	    echo >&2 "Trivially automerged."
+	else
+	    git merge-index -o git-merge-one-file -a
+	fi
+
+	# Do not register the cleanly merged paths in the index yet.
+	# this is not a real merge before committing, but just carrying
+	# the working tree changes along.
+	unmerged=`git ls-files -u`
+	git read-tree --reset $new
+	case "$unmerged" in
+	'')	;;
+	*)
+		(
+			z40=0000000000000000000000000000000000000000
+			echo "$unmerged" |
+			sed -e 's/^[0-7]* [0-9a-f]* /'"0 $z40 /"
+			echo "$unmerged"
+		) | git update-index --index-info
+		;;
+	esac
+	exit 0
+    )
+    saved_err=$?
+    if test "$saved_err" = 0
+    then
+	test "$new" = "$old" || git diff-index --name-status "$new"
+    fi
+    (exit $saved_err)
 fi
 
 # 
@@ -132,9 +196,11 @@ fi
 #
 if [ "$?" -eq 0 ]; then
 	if [ "$newbranch" ]; then
-		leading=`expr "refs/heads/$newbranch" : '\(.*\)/'` &&
-		mkdir -p "$GIT_DIR/$leading" &&
-		echo $new >"$GIT_DIR/refs/heads/$newbranch" || exit
+		if [ "$newbranch_log" ]; then
+			mkdir -p $(dirname "$GIT_DIR/logs/refs/heads/$newbranch")
+			touch "$GIT_DIR/logs/refs/heads/$newbranch"
+		fi
+		git-update-ref -m "checkout: Created from $new_name" "refs/heads/$newbranch" $new || exit
 		branch="$newbranch"
 	fi
 	[ "$branch" ] &&