Merge branch 'rr/rebase-autostash'

* rr/rebase-autostash:
  rebase: implement --[no-]autostash and rebase.autostash
  rebase --merge: return control to caller, for housekeeping
  rebase -i: return control to caller, for housekeeping
  am: return control to caller, for housekeeping
  rebase: prepare to do generic housekeeping
  rebase -i: don't error out if $state_dir already exists
  am: tighten a conditional that checks for $dotest

8 files changed, 235 insertions, 16 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 6e53fc5074..7fd4035cb5 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -1867,6 +1867,14 @@ rebase.stat::
 rebase.autosquash::
 	If set to true enable '--autosquash' option by default.
 
+rebase.autostash::
+	When set to true, automatically create a temporary stash
+	before the operation begins, and apply it after the operation
+	ends.  This means that you can run rebase on a dirty worktree.
+	However, use with care: the final stash application after a
+	successful rebase might result in non-trivial conflicts.
+	Defaults to false.
+
 receive.autogc::
 	By default, git-receive-pack will run "git-gc --auto" after
 	receiving data from git-push and updating refs.  You can stop
diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index aca840525e..c84854ae87 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -208,6 +208,9 @@ rebase.stat::
 rebase.autosquash::
 	If set to true enable '--autosquash' option by default.
 
+rebase.autostash::
+	If set to true enable '--autostash' option by default.
+
 OPTIONS
 -------
 --onto <newbase>::
@@ -394,6 +397,13 @@ If the '--autosquash' option is enabled by default using the
 configuration variable `rebase.autosquash`, this option can be
 used to override and disable this setting.
 
+--[no-]autostash::
+	Automatically create a temporary stash before the operation
+	begins, and apply it after the operation ends.  This means
+	that you can run rebase on a dirty worktree.  However, use
+	with care: the final stash application after a successful
+	rebase might result in non-trivial conflicts.
+
 --no-ff::
 	With --interactive, cherry-pick all rebased commits instead of
 	fast-forwarding over the unchanged ones.  This ensures that the
diff --git a/git-am.sh b/git-am.sh
index c092855dd7..1cf3d1dacf 100755
--- a/git-am.sh
+++ b/git-am.sh
@@ -446,6 +446,8 @@ done
 # If the dotest directory exists, but we have finished applying all the
 # patches in them, clear it out.
 if test -d "$dotest" &&
+   test -f "$dotest/last" &&
+   test -f "$dotest/next" &&
    last=$(cat "$dotest/last") &&
    next=$(cat "$dotest/next") &&
    test $# != 0 &&
@@ -454,7 +456,7 @@ then
    rm -fr "$dotest"
 fi
 
-if test -d "$dotest"
+if test -d "$dotest" && test -f "$dotest/last" && test -f "$dotest/next"
 then
 	case "$#,$skip$resolved$abort" in
 	0,*t*)
@@ -904,5 +906,10 @@ if test -s "$dotest"/rewritten; then
     fi
 fi
 
-rm -fr "$dotest"
-git gc --auto
+# If am was called with --rebasing (from git-rebase--am), it's up to
+# the caller to take care of housekeeping.
+if ! test -f "$dotest/rebasing"
+then
+	rm -fr "$dotest"
+	git gc --auto
+fi
diff --git a/git-rebase--am.sh b/git-rebase--am.sh
index f84854f09a..34e3102fcb 100644
--- a/git-rebase--am.sh
+++ b/git-rebase--am.sh
@@ -7,12 +7,12 @@ case "$action" in
 continue)
 	git am --resolved --resolvemsg="$resolvemsg" &&
 	move_to_original_branch
-	exit
+	return
 	;;
 skip)
 	git am --skip --resolvemsg="$resolvemsg" &&
 	move_to_original_branch
-	exit
+	return
 	;;
 esac
 
@@ -56,7 +56,7 @@ else
 
 		As a result, git cannot rebase them.
 		EOF
-		exit $?
+		return $?
 	fi
 
 	git am $git_am_opt --rebasing --resolvemsg="$resolvemsg" <"$GIT_DIR/rebased-patches"
@@ -68,7 +68,7 @@ fi
 if test 0 != $ret
 then
 	test -d "$state_dir" && write_basic_state
-	exit $ret
+	return $ret
 fi
 
 move_to_original_branch
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 5822b2c592..f953d8d224 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -628,17 +628,16 @@ do_next () {
 		"$GIT_DIR"/hooks/post-rewrite rebase < "$rewritten_list"
 		true # we don't care if this hook failed
 	fi &&
-	rm -rf "$state_dir" &&
-	git gc --auto &&
 	warn "Successfully rebased and updated $head_name."
 
-	exit
+	return 1 # not failure; just to break the do_rest loop
 }
 
+# can only return 0, when the infinite loop breaks
 do_rest () {
 	while :
 	do
-		do_next
+		do_next || break
 	done
 }
 
@@ -805,11 +804,13 @@ first and then run 'git rebase --continue' again."
 
 	require_clean_work_tree "rebase"
 	do_rest
+	return 0
 	;;
 skip)
 	git rerere clear
 
 	do_rest
+	return 0
 	;;
 edit-todo)
 	git stripspace --strip-comments <"$todo" >"$todo".new
@@ -842,7 +843,7 @@ then
 fi
 
 orig_head=$(git rev-parse --verify HEAD) || die "No HEAD?"
-mkdir "$state_dir" || die "Could not create temporary $state_dir"
+mkdir -p "$state_dir" || die "Could not create temporary $state_dir"
 
 : > "$state_dir"/interactive || die "Could not mark as interactive"
 write_basic_state
diff --git a/git-rebase--merge.sh b/git-rebase--merge.sh
index b10f2cf21b..16d18176ec 100644
--- a/git-rebase--merge.sh
+++ b/git-rebase--merge.sh
@@ -96,7 +96,6 @@ finish_rb_merge () {
 			"$GIT_DIR"/hooks/post-rewrite rebase <"$state_dir"/rewritten
 		fi
 	fi
-	rm -r "$state_dir"
 	say All done.
 }
 
@@ -110,7 +109,7 @@ continue)
 		continue_merge
 	done
 	finish_rb_merge
-	exit
+	return
 	;;
 skip)
 	read_state
@@ -122,7 +121,7 @@ skip)
 		continue_merge
 	done
 	finish_rb_merge
-	exit
+	return
 	;;
 esac
 
diff --git a/git-rebase.sh b/git-rebase.sh
index 2c692c33e9..d0c11a910a 100755
--- a/git-rebase.sh
+++ b/git-rebase.sh
@@ -13,6 +13,7 @@ git-rebase --continue | --abort | --skip | --edit-todo
  Available options are
 v,verbose!         display a diffstat of what changed upstream
 q,quiet!           be quiet. implies --no-stat
+autostash!         automatically stash/stash pop before and after
 onto=!             rebase onto given branch instead of upstream
 p,preserve-merges! try to recreate merges instead of ignoring them
 s,strategy=!       use the given merge strategy
@@ -64,6 +65,7 @@ apply_dir="$GIT_DIR"/rebase-apply
 verbose=
 diffstat=
 test "$(git config --bool rebase.stat)" = true && diffstat=t
+autostash="$(git config --bool rebase.autostash || echo false)"
 git_am_opt=
 rebase_root=
 force_rebase=
@@ -143,6 +145,29 @@ move_to_original_branch () {
 	esac
 }
 
+finish_rebase () {
+	if test -f "$state_dir/autostash"
+	then
+		stash_sha1=$(cat "$state_dir/autostash")
+		if git stash apply $stash_sha1 2>&1 >/dev/null
+		then
+			echo "$(gettext 'Applied autostash.')"
+		else
+			ref_stash=refs/stash &&
+			>>"$GIT_DIR/logs/$ref_stash" &&
+			git update-ref -m "autostash" $ref_stash $stash_sha1 ||
+			die "$(eval_gettext 'Cannot store $stash_sha1')"
+
+			gettext 'Applying autostash resulted in conflicts.
+Your changes are safe in the stash.
+You can run "git stash pop" or "git stash drop" it at any time.
+'
+		fi
+	fi
+	git gc --auto &&
+	rm -rf "$state_dir"
+}
+
 run_specific_rebase () {
 	if [ "$interactive_rebase" = implied ]; then
 		GIT_EDITOR=:
@@ -150,6 +175,12 @@ run_specific_rebase () {
 		autosquash=
 	fi
 	. git-rebase--$type
+	ret=$?
+	if test $ret -eq 0
+	then
+		finish_rebase
+	fi
+	exit $ret
 }
 
 run_pre_rebase_hook () {
@@ -241,6 +272,9 @@ do
 	--stat)
 		diffstat=t
 		;;
+	--autostash)
+		autostash=true
+		;;
 	-v)
 		verbose=t
 		diffstat=t
@@ -341,7 +375,7 @@ abort)
 		;;
 	esac
 	output git reset --hard $orig_head
-	rm -r "$state_dir"
+	finish_rebase
 	exit
 	;;
 edit-todo)
@@ -480,6 +514,18 @@ case "$#" in
 	;;
 esac
 
+if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
+then
+	stash_sha1=$(git stash create "autostash") ||
+	die "$(gettext 'Cannot autostash')"
+
+	mkdir -p "$state_dir" &&
+	echo $stash_sha1 >"$state_dir/autostash" &&
+	stash_abbrev=$(git rev-parse --short $stash_sha1) &&
+	echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
+	git reset --hard
+fi
+
 require_clean_work_tree "rebase" "$(gettext "Please commit or stash them.")"
 
 # Now we are rebasing commits $upstream..$orig_head (or with --root,
diff --git a/t/t3420-rebase-autostash.sh b/t/t3420-rebase-autostash.sh
new file mode 100755
index 0000000000..479cbb215f
--- /dev/null
+++ b/t/t3420-rebase-autostash.sh
@@ -0,0 +1,148 @@
+#!/bin/sh
+#
+# Copyright (c) 2013 Ramkumar Ramachandra
+#
+
+test_description='git rebase --autostash tests'
+. ./test-lib.sh
+
+test_expect_success setup '
+	echo hello-world >file0 &&
+	git add . &&
+	test_tick &&
+	git commit -m "initial commit" &&
+	git checkout -b feature-branch &&
+	echo another-hello >file1 &&
+	echo goodbye >file2 &&
+	git add . &&
+	test_tick &&
+	git commit -m "second commit" &&
+	echo final-goodbye >file3 &&
+	git add . &&
+	test_tick &&
+	git commit -m "third commit" &&
+	git checkout -b unrelated-onto-branch master &&
+	echo unrelated >file4 &&
+	git add . &&
+	test_tick &&
+	git commit -m "unrelated commit" &&
+	git checkout -b related-onto-branch master &&
+	echo conflicting-change >file2 &&
+	git add . &&
+	test_tick &&
+	git commit -m "related commit"
+'
+
+testrebase() {
+	type=$1
+	dotest=$2
+
+	test_expect_success "rebase$type: dirty worktree, non-conflicting rebase" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		git rebase$type unrelated-onto-branch &&
+		grep unrelated file4 &&
+		grep dirty file3 &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: dirty index, non-conflicting rebase" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		git add file3 &&
+		git rebase$type unrelated-onto-branch &&
+		grep unrelated file4 &&
+		grep dirty file3 &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: conflicting rebase" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		test_must_fail git rebase$type related-onto-branch &&
+		test_path_is_file $dotest/autostash &&
+		! grep dirty file3 &&
+		rm -rf $dotest &&
+		git reset --hard &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: --continue" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		test_must_fail git rebase$type related-onto-branch &&
+		test_path_is_file $dotest/autostash &&
+		! grep dirty file3 &&
+		echo "conflicting-plus-goodbye" >file2 &&
+		git add file2 &&
+		git rebase --continue &&
+		test_path_is_missing $dotest/autostash &&
+		grep dirty file3 &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: --skip" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		test_must_fail git rebase$type related-onto-branch &&
+		test_path_is_file $dotest/autostash &&
+		! grep dirty file3 &&
+		git rebase --skip &&
+		test_path_is_missing $dotest/autostash &&
+		grep dirty file3 &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: --abort" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >>file3 &&
+		test_must_fail git rebase$type related-onto-branch &&
+		test_path_is_file $dotest/autostash &&
+		! grep dirty file3 &&
+		git rebase --abort &&
+		test_path_is_missing $dotest/autostash &&
+		grep dirty file3 &&
+		git checkout feature-branch
+	'
+
+	test_expect_success "rebase$type: non-conflicting rebase, conflicting stash" '
+		test_config rebase.autostash true &&
+		git reset --hard &&
+		git checkout -b rebased-feature-branch feature-branch &&
+		test_when_finished git branch -D rebased-feature-branch &&
+		echo dirty >file4 &&
+		git add file4 &&
+		git rebase$type unrelated-onto-branch &&
+		test_path_is_missing $dotest &&
+		git reset --hard &&
+		grep unrelated file4 &&
+		! grep dirty file4 &&
+		git checkout feature-branch &&
+		git stash pop &&
+		grep dirty file4
+	'
+}
+
+testrebase "" .git/rebase-apply
+testrebase " --merge" .git/rebase-merge
+testrebase " --interactive" .git/rebase-merge
+
+test_done