X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=git-checkout.sh;h=a11c939c30f46561adb8179570d825a85fb8b57b;hb=refs%2Fheads%2Fmaint;hp=4cf30e2c0529e90886e6edfd485cec67a278e224;hpb=93dcab2937624ebb97f91807576cddb242a55a46;p=git.git

diff --git a/git-checkout.sh b/git-checkout.sh
index 4cf30e2c..a11c939c 100755
--- a/git-checkout.sh
+++ b/git-checkout.sh
@@ -1,15 +1,15 @@
 #!/bin/sh
-. git-sh-setup
 
-usage () {
-    die "usage: git checkout [-f] [-b <new_branch>] [<branch>] [<paths>...]"
-}
+USAGE='[-f] [-b <new_branch>] [-m] [<branch>] [<paths>...]'
+SUBDIRECTORY_OK=Sometimes
+. git-sh-setup
 
 old=$(git-rev-parse HEAD)
 new=
 force=
 branch=
 newbranch=
+merge=
 while [ "$#" != "0" ]; do
     arg="$1"
     shift
@@ -22,11 +22,14 @@ while [ "$#" != "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."
 		;;
 	"-f")
 		force=1
 		;;
+	-m)
+		merge=1
+		;;
 	--)
 		break
 		;;
@@ -72,16 +75,22 @@ 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
 		# from a specific tree-ish; note that this is for
 		# rescuing paths and is never meant to remove what
 		# is not in the named tree-ish.
-		git-ls-tree -r "$new" "$@" |
+		git-ls-tree --full-name -r "$new" "$@" |
 		git-update-index --index-info || exit $?
 	fi
 	git-checkout-index -f -u -- "$@"
@@ -97,6 +106,14 @@ else
 	fi
 fi
 
+# We are switching branches and checking out trees, so
+# we *NEED* to be at the toplevel.
+cdup=$(git-rev-parse --show-cdup)
+if test ! -z "$cdup"
+then
+	cd "$cdup"
+fi
+
 [ -z "$new" ] && new=$old
 
 # If we don't have an old branch that we're switching to,
@@ -106,7 +123,8 @@ 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
@@ -114,11 +132,55 @@ 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
 
 # 
-# Switch the HEAD pointer to the new branch if it we
+# Switch the HEAD pointer to the new branch if we
 # checked out a branch head, and remove any potential
 # old MERGE_HEAD's (subsequent commits will clearly not
 # be based on them, since we re-set the index)