[PATCH v3 0/7] Re-roll rr/rebase-checkout-reflog

@@ -1035,7 +1035,6 @@ got_nothing:
 }
 
 struct grab_1st_switch_cbdata {
-	int found;
 	struct strbuf buf;
 	unsigned char nsha1[20];
 };

@@ -1059,7 +1058,6 @@ static int grab_1st_switch(unsigned char *osha1, unsigned char *nsha1,
 	for (end = target; *end && *end != '\n'; end++)
 		;
 	strbuf_add(&cb->buf, target, end - target);
-	cb->found = 1;
 	return 1;
 }
 

@@ -667,7 +667,7 @@ test_expect_success 'status when cherry-picking after resolving conflicts' '
 	test_i18ncmp expected actual
 '
 
-test_expect_success 'status showing detached from a tag' '
+test_expect_success 'status showing detached at and from a tag' '
 	test_commit atag tagging &&
 	git checkout atag &&
 	cat >expected <<-\EOF

@@ -675,6 +675,14 @@ test_expect_success 'status showing detached from a tag' '
 	nothing to commit (use -u to show untracked files)
 	EOF
 	git status --untracked-files=no >actual &&
+	test_i18ncmp expected actual &&
+
+	git reset --hard HEAD^ &&
+	cat >expected <<-\EOF
+	# HEAD detached from atag
+	nothing to commit (use -u to show untracked files)
+	EOF
+	git status --untracked-files=no >actual &&
 	test_i18ncmp expected actual
 '
 

@@ -77,7 +77,7 @@ test_expect_success 'status when rebase in progress before resolving conflicts'
 	ONTO=$(git rev-parse --short HEAD^^) &&
 	test_must_fail git rebase HEAD^ --onto HEAD^^ &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
 	#   (fix conflicts and then run "git rebase --continue")
 	#   (use "git rebase --skip" to skip this patch)

@@ -104,7 +104,7 @@ test_expect_success 'status when rebase in progress before rebase --continue' '
 	echo three >main.txt &&
 	git add main.txt &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
 	#   (all conflicts fixed: run "git rebase --continue")
 	#

@@ -136,7 +136,7 @@ test_expect_success 'status during rebase -i when conflicts unresolved' '
 	ONTO=$(git rev-parse --short rebase_i_conflicts) &&
 	test_must_fail git rebase -i rebase_i_conflicts &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO'\''.
 	#   (fix conflicts and then run "git rebase --continue")
 	#   (use "git rebase --skip" to skip this patch)

@@ -162,7 +162,7 @@ test_expect_success 'status during rebase -i after resolving conflicts' '
 	test_must_fail git rebase -i rebase_i_conflicts &&
 	git add main.txt &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently rebasing branch '\''rebase_i_conflicts_second'\'' on '\''$ONTO'\''.
 	#   (all conflicts fixed: run "git rebase --continue")
 	#

@@ -188,10 +188,9 @@ test_expect_success 'status when rebasing -i in edit mode' '
 	export FAKE_LINES &&
 	test_when_finished "git rebase --abort" &&
 	ONTO=$(git rev-parse --short HEAD~2) &&
-	TGT=$(git rev-parse --short two_rebase_i) &&
 	git rebase -i HEAD~2 &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $TGT
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''rebase_i_edit'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -216,9 +215,8 @@ test_expect_success 'status when splitting a commit' '
 	ONTO=$(git rev-parse --short HEAD~3) &&
 	git rebase -i HEAD~3 &&
 	git reset HEAD^ &&
-	TGT=$(git rev-parse --short HEAD) &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $TGT
+	# rebase in progress; onto $ONTO
 	# You are currently splitting a commit while rebasing branch '\''split_commit'\'' on '\''$ONTO'\''.
 	#   (Once your working directory is clean, run "git rebase --continue")
 	#

@@ -246,11 +244,10 @@ test_expect_success 'status after editing the last commit with --amend during a
 	export FAKE_LINES &&
 	test_when_finished "git rebase --abort" &&
 	ONTO=$(git rev-parse --short HEAD~3) &&
-	TGT=$(git rev-parse --short three_amend) &&
 	git rebase -i HEAD~3 &&
 	git commit --amend -m "foo" &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $TGT
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''amend_last'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -280,7 +277,7 @@ test_expect_success 'status: (continue first edit) second edit' '
 	git rebase -i HEAD~3 &&
 	git rebase --continue &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -302,7 +299,7 @@ test_expect_success 'status: (continue first edit) second edit and split' '
 	git rebase --continue &&
 	git reset HEAD^ &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (Once your working directory is clean, run "git rebase --continue")
 	#

@@ -329,7 +326,7 @@ test_expect_success 'status: (continue first edit) second edit and amend' '
 	git rebase --continue &&
 	git commit --amend -m "foo" &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -351,7 +348,7 @@ test_expect_success 'status: (amend first edit) second edit' '
 	git commit --amend -m "a" &&
 	git rebase --continue &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -374,7 +371,7 @@ test_expect_success 'status: (amend first edit) second edit and split' '
 	git rebase --continue &&
 	git reset HEAD^ &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (Once your working directory is clean, run "git rebase --continue")
 	#

@@ -402,7 +399,7 @@ test_expect_success 'status: (amend first edit) second edit and amend' '
 	git rebase --continue &&
 	git commit --amend -m "d" &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -426,7 +423,7 @@ test_expect_success 'status: (split first edit) second edit' '
 	git commit -m "e" &&
 	git rebase --continue &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -451,7 +448,7 @@ test_expect_success 'status: (split first edit) second edit and split' '
 	git rebase --continue &&
 	git reset HEAD^ &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently splitting a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (Once your working directory is clean, run "git rebase --continue")
 	#

@@ -481,7 +478,7 @@ test_expect_success 'status: (split first edit) second edit and amend' '
 	git rebase --continue &&
 	git commit --amend -m "h" &&
 	cat >expected <<-EOF &&
-	# HEAD detached from $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently editing a commit while rebasing branch '\''several_edits'\'' on '\''$ONTO'\''.
 	#   (use "git commit --amend" to amend the current commit)
 	#   (use "git rebase --continue" once you are satisfied with your changes)

@@ -601,7 +598,7 @@ test_expect_success 'status when rebase conflicts with statushints disabled' '
 	ONTO=$(git rev-parse --short HEAD^^) &&
 	test_must_fail git rebase HEAD^ --onto HEAD^^ &&
 	cat >expected <<-EOF &&
-	# HEAD detached at $ONTO
+	# rebase in progress; onto $ONTO
 	# You are currently rebasing branch '\''statushints_disabled'\'' on '\''$ONTO'\''.
 	#
 	# Unmerged paths:

@@ -1174,7 +1174,10 @@ void wt_status_print(struct wt_status *s)
 			branch_name += 11;
 		else if (!strcmp(branch_name, "HEAD")) {
 			branch_status_color = color(WT_STATUS_NOBRANCH, s);
-			if (state.detached_from) {
+			if (state.rebase_in_progress || state.rebase_interactive_in_progress) {
+				on_what = _("rebase in progress; onto ");
+				branch_name = state.onto;
+			} else if (state.detached_from) {
 				unsigned char sha1[20];
 				branch_name = state.detached_from;
 				if (!get_sha1("HEAD", sha1) &&

@@ -116,4 +116,38 @@ test_expect_success 'master...' '
 	test "z$(git rev-parse --verify HEAD)" = "z$(git rev-parse --verify master^)"
 '
 
+test_expect_failure '"checkout -" works after a rebase A' '
+	git checkout master &&
+	git checkout other &&
+	git rebase master &&
+	git checkout - &&
+	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
+'
+
+test_expect_failure '"checkout -" works after a rebase A B' '
+	git branch moodle master~1 &&
+	git checkout master &&
+	git checkout other &&
+	git rebase master moodle &&
+	git checkout - &&
+	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
+'
+
+test_expect_failure '"checkout -" works after a rebase -i A' '
+	git checkout master &&
+	git checkout other &&
+	git rebase -i master &&
+	git checkout - &&
+	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
+'
+
+test_expect_failure '"checkout -" works after a rebase -i A B' '
+	git branch foodle master~1 &&
+	git checkout master &&
+	git checkout other &&
+	git rebase master foodle &&
+	git checkout - &&
+	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
+'
+
 test_done

@@ -587,7 +587,7 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 				   struct branch_info *new)
 {
 	struct strbuf msg = STRBUF_INIT;
-	const char *old_desc;
+	const char *old_desc, *reflog_msg;
 	if (opts->new_branch) {
 		if (opts->new_orphan_branch) {
 			if (opts->new_branch_log && !log_all_ref_updates) {

@@ -620,8 +620,13 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 	old_desc = old->name;
 	if (!old_desc && old->commit)
 		old_desc = sha1_to_hex(old->commit->object.sha1);
-	strbuf_addf(&msg, "checkout: moving from %s to %s",
-		    old_desc ? old_desc : "(invalid)", new->name);
+
+	reflog_msg = getenv("GIT_REFLOG_ACTION");
+	if (!reflog_msg)
+		strbuf_addf(&msg, "checkout: moving from %s to %s",
+			old_desc ? old_desc : "(invalid)", new->name);
+	else
+		strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
 
 	if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
 		/* Nothing to do. */

@@ -116,7 +116,7 @@ test_expect_success 'master...' '
 	test "z$(git rev-parse --verify HEAD)" = "z$(git rev-parse --verify master^)"
 '
 
-test_expect_failure '"checkout -" works after a rebase A' '
+test_expect_success '"checkout -" works after a rebase A' '
 	git checkout master &&
 	git checkout other &&
 	git rebase master &&

@@ -124,7 +124,7 @@ test_expect_failure '"checkout -" works after a rebase A' '
 	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
 '
 
-test_expect_failure '"checkout -" works after a rebase A B' '
+test_expect_success '"checkout -" works after a rebase A B' '
 	git branch moodle master~1 &&
 	git checkout master &&
 	git checkout other &&

@@ -133,7 +133,7 @@ test_expect_failure '"checkout -" works after a rebase A B' '
 	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
 '
 
-test_expect_failure '"checkout -" works after a rebase -i A' '
+test_expect_success '"checkout -" works after a rebase -i A' '
 	git checkout master &&
 	git checkout other &&
 	git rebase -i master &&

@@ -141,7 +141,7 @@ test_expect_failure '"checkout -" works after a rebase -i A' '
 	test "z$(git symbolic-ref HEAD)" = "zrefs/heads/master"
 '
 
-test_expect_failure '"checkout -" works after a rebase -i A B' '
+test_expect_success '"checkout -" works after a rebase -i A B' '
 	git branch foodle master~1 &&
 	git checkout master &&
 	git checkout other &&

@@ -46,6 +46,8 @@ set_reflog_action am
 require_work_tree
 cd_to_toplevel
 
+base_reflog_action="$GIT_REFLOG_ACTION"
+
 git var GIT_COMMITTER_IDENT >/dev/null ||
 	die "$(gettext "You need to set your committer info first")"
 

@@ -884,7 +886,7 @@ did you forget to use 'git add'?"
 		fi &&
 		git commit-tree $tree ${parent:+-p} $parent <"$dotest/final-commit"
 	) &&
-	git update-ref -m "$GIT_REFLOG_ACTION: $FIRSTLINE" HEAD $commit $parent ||
+	git update-ref -m "$base_reflog_action: $FIRSTLINE" HEAD $commit $parent ||
 	stop_here $this
 
 	if test -f "$dotest/original-commit"; then

@@ -5,11 +5,13 @@
 
 case "$action" in
 continue)
+	GIT_REFLOG_ACTION="$base_reflog_action"
 	git am --resolved --resolvemsg="$resolvemsg" &&
 	move_to_original_branch
 	return
 	;;
 skip)
+	GIT_REFLOG_ACTION="$base_reflog_action"
 	git am --skip --resolvemsg="$resolvemsg" &&
 	move_to_original_branch
 	return

@@ -40,9 +42,11 @@ else
 		rm -f "$GIT_DIR/rebased-patches"
 		case "$head_name" in
 		refs/heads/*)
+			GIT_REFLOG_ACTION="$base_reflog_action: checkout $head_name"
 			git checkout -q "$head_name"
 			;;
 		*)
+			GIT_REFLOG_ACTION="$base_reflog_action: checkout $orig_head"
 			git checkout -q "$orig_head"
 			;;
 		esac

@@ -59,6 +63,9 @@ else
 		return $?
 	fi
 
+	# always reset GIT_REFLOG_ACTION before calling any external
+	# scripts; they have no idea about our base_reflog_action
+	GIT_REFLOG_ACTION="$base_reflog_action"
 	git am $git_am_opt --rebasing --resolvemsg="$resolvemsg" <"$GIT_DIR/rebased-patches"
 	ret=$?
 

@@ -47,6 +47,13 @@ set_reflog_action rebase
 require_work_tree_exists
 cd_to_toplevel
 
+# Should contain a base string like "rebase" (or "rebase -i (start)")
+# to which a more information like ": checkout foom" can be appended
+# to set the final GIT_REFLOG_ACTION.  If you append to
+# GIT_REFLOG_ACTION directly, you risk appending to a prebuilt string
+# like "rebase: checkout mool" from a previous append.
+base_reflog_action="$GIT_REFLOG_ACTION"
+
 LF='
 '
 ok_to_skip_pre_rebase=

@@ -336,7 +343,8 @@ then
 	# Only interactive rebase uses detailed reflog messages
 	if test "$type" = interactive && test "$GIT_REFLOG_ACTION" = rebase
 	then
-		GIT_REFLOG_ACTION="rebase -i ($action)"
+		GIT_REFLOG_ACTION="rebase -i ($1)"
+		base_reflog_action="$GIT_REFLOG_ACTION"
 		export GIT_REFLOG_ACTION
 	fi
 fi

@@ -543,7 +551,11 @@ then
 	if test -z "$force_rebase"
 	then
 		# Lazily switch to the target branch if needed...
-		test -z "$switch_to" || git checkout "$switch_to" --
+		if test -n "$switch_to"
+		then
+			GIT_REFLOG_ACTION="$base_reflog_action: checkout $switch_to"
+			git checkout "$switch_to" --
+		fi
 		say "$(eval_gettext "Current branch \$branch_name is up to date.")"
 		exit 0
 	else

@@ -568,6 +580,8 @@ test "$type" = interactive && run_specific_rebase
 
 # Detach HEAD and reset the tree
 say "$(gettext "First, rewinding head to replay your work on top of it...")"
+
+GIT_REFLOG_ACTION="$base_reflog_action: checkout $onto_name"
 git checkout -q "$onto^0" || die "could not detach HEAD"
 git update-ref ORIG_HEAD $orig_head
 

@@ -95,12 +95,15 @@ commit_message () {
 	git cat-file commit "$1" | sed "1,/^$/d"
 }
 
-orig_reflog_action="$GIT_REFLOG_ACTION"
+base_reflog_action="$GIT_REFLOG_ACTION"
 
 comment_for_reflog () {
-	case "$orig_reflog_action" in
+	case "$base_reflog_action" in
+	# if GIT_REFLOG_ACTION was set by caller git-rebase, overwrite
+	# it with rebase -i.
 	''|rebase*)
 		GIT_REFLOG_ACTION="rebase -i ($1)"
+		base_reflog_action="$GIT_REFLOG_ACTION"
 		export GIT_REFLOG_ACTION
 		;;
 	esac

@@ -326,6 +329,7 @@ pick_one_preserving_merges () {
 		if [ "$1" != "-n" ]
 		then
 			# detach HEAD to current parent
+			GIT_REFLOG_ACTION="$base_reflog_action: checkout $first_parent"
 			output git checkout $first_parent 2> /dev/null ||
 				die "Cannot move HEAD to $first_parent"
 		fi

@@ -608,10 +612,10 @@ do_next () {
 	newhead=$(git rev-parse HEAD) &&
 	case $head_name in
 	refs/*)
-		message="$GIT_REFLOG_ACTION: $head_name onto $onto" &&
+		message="$base_reflog_action: $head_name onto $onto" &&
 		git update-ref -m "$message" $head_name $newhead $orig_head &&
 		git symbolic-ref \
-		  -m "$GIT_REFLOG_ACTION: returning to $head_name" \
+		  -m "$base_reflog_action: returning to $head_name" \
 		  HEAD $head_name
 		;;
 	esac && {

@@ -838,6 +842,7 @@ comment_for_reflog start
 
 if test ! -z "$switch_to"
 then
+	GIT_REFLOG_ACTION="$base_reflog_action: checkout $switch_to"
 	output git checkout "$switch_to" -- ||
 		die "Could not checkout $switch_to"
 fi

@@ -981,6 +986,7 @@ has_action "$todo" ||
 
 test -d "$rewritten" || test -n "$force_rebase" || skip_unnecessary_picks
 
+GIT_REFLOG_ACTION="$base_reflog_action: checkout $onto_name"
 output git checkout $onto || die_abort "could not detach HEAD"
 git update-ref ORIG_HEAD $orig_head
 do_rest

@@ -934,6 +934,21 @@ test_expect_success 'rebase --edit-todo can be used to modify todo' '
 	test L = $(git cat-file commit HEAD | sed -ne \$p)
 '
 
+test_expect_success 'rebase -i produces readable reflog' '
+	git reset --hard &&
+	git branch -f branch-reflog-test H &&
+	git rebase -i --onto I F branch-reflog-test &&
+	cat >expect <<-\EOF &&
+	rebase -i (start): checkout I
+	rebase -i (pick): G
+	rebase -i (pick): H
+	rebase -i (finish): returning to refs/heads/branch-reflog-test
+	EOF
+	tail -n 4 .git/logs/HEAD |
+	sed -e "s/.*	//" >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'rebase -i respects core.commentchar' '
 	git reset --hard &&
 	git checkout E^0 &&