[PATCH v2] sequencer: honor GIT_REFLOG_ACTION

["Elijah Newren via GitGitGadget" <gitgitgadget@gmail.com>]

From: Elijah Newren <newren@gmail.com>

There is a lot of code to honor GIT_REFLOG_ACTION throughout git,
including some in sequencer.c; unfortunately, reflog_message() and its
callers ignored it.  Instruct reflog_message() to check the existing
environment variable, and use it when present as an override to
action_name().

Also restructure pick_commits() to only temporarily modify
GIT_REFLOG_ACTION for a short duration and then restore the old value,
so that when we do this setting within a loop we do not keep adding "
(pick)" substrings and end up with a reflog message of the form
    rebase (pick) (pick) (pick) (finish): returning to refs/heads/master

Signed-off-by: Elijah Newren <newren@gmail.com>
---
    sequencer: honor GIT_REFLOG_ACTION
    
    Changes since v1:
    
     * Just use preprocessor constant (instead of mix of it and string
       constant)
     * Add a comment next to code that surprised both Phillip and Dscho

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-746%2Fnewren%2Fhonor-reflog-action-in-sequencer-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-746/newren/honor-reflog-action-in-sequencer-v2
Pull-Request: https://github.com/git/git/pull/746

Range-diff vs v1:

 1:  5c6d74af194 ! 1:  a12cc2d2c3a sequencer: honor GIT_REFLOG_ACTION
     @@ sequencer.c: static const char *reflog_message(struct replay_opts *opts,
       {
       	va_list ap;
       	static struct strbuf buf = STRBUF_INIT;
     -+	char *reflog_action = getenv("GIT_REFLOG_ACTION");
     ++	char *reflog_action = getenv(GIT_REFLOG_ACTION);
       
       	va_start(ap, fmt);
       	strbuf_reset(&buf);
     @@ sequencer.c: static int pick_commits(struct repository *r,
       	int res = 0, reschedule = 0;
      +	char *prev_reflog_action;
       
     ++	/* Note that 0 for 3rd parameter of setenv means set only if not set */
       	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
      +	prev_reflog_action = xstrdup(getenv(GIT_REFLOG_ACTION));
       	if (opts->allow_ff)


 sequencer.c               | 10 ++++++++--
 t/t3406-rebase-message.sh | 16 ++++++++--------
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/sequencer.c b/sequencer.c
index e528225e787..24a62d5aa5d 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -3708,10 +3708,11 @@ static const char *reflog_message(struct replay_opts *opts,
 {
 	va_list ap;
 	static struct strbuf buf = STRBUF_INIT;
+	char *reflog_action = getenv(GIT_REFLOG_ACTION);
 
 	va_start(ap, fmt);
 	strbuf_reset(&buf);
-	strbuf_addstr(&buf, action_name(opts));
+	strbuf_addstr(&buf, reflog_action ? reflog_action : action_name(opts));
 	if (sub_action)
 		strbuf_addf(&buf, " (%s)", sub_action);
 	if (fmt) {
@@ -3799,8 +3800,11 @@ static int pick_commits(struct repository *r,
 			struct replay_opts *opts)
 {
 	int res = 0, reschedule = 0;
+	char *prev_reflog_action;
 
+	/* Note that 0 for 3rd parameter of setenv means set only if not set */
 	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
+	prev_reflog_action = xstrdup(getenv(GIT_REFLOG_ACTION));
 	if (opts->allow_ff)
 		assert(!(opts->signoff || opts->no_commit ||
 				opts->record_origin || opts->edit));
@@ -3845,12 +3849,14 @@ static int pick_commits(struct repository *r,
 		}
 		if (item->command <= TODO_SQUASH) {
 			if (is_rebase_i(opts))
-				setenv("GIT_REFLOG_ACTION", reflog_message(opts,
+				setenv(GIT_REFLOG_ACTION, reflog_message(opts,
 					command_to_string(item->command), NULL),
 					1);
 			res = do_pick_commit(r, item->command, item->commit,
 					     opts, is_final_fixup(todo_list),
 					     &check_todo);
+			if (is_rebase_i(opts))
+				setenv(GIT_REFLOG_ACTION, prev_reflog_action, 1);
 			if (is_rebase_i(opts) && res < 0) {
 				/* Reschedule */
 				advise(_(rescheduled_advice),
diff --git a/t/t3406-rebase-message.sh b/t/t3406-rebase-message.sh
index 61b76f33019..927a4f4a4e4 100755
--- a/t/t3406-rebase-message.sh
+++ b/t/t3406-rebase-message.sh
@@ -89,22 +89,22 @@ test_expect_success 'GIT_REFLOG_ACTION' '
 	git checkout -b reflog-topic start &&
 	test_commit reflog-to-rebase &&
 
-	git rebase --apply reflog-onto &&
+	git rebase reflog-onto &&
 	git log -g --format=%gs -3 >actual &&
 	cat >expect <<-\EOF &&
-	rebase finished: returning to refs/heads/reflog-topic
-	rebase: reflog-to-rebase
-	rebase: checkout reflog-onto
+	rebase (finish): returning to refs/heads/reflog-topic
+	rebase (pick): reflog-to-rebase
+	rebase (start): checkout reflog-onto
 	EOF
 	test_cmp expect actual &&
 
 	git checkout -b reflog-prefix reflog-to-rebase &&
-	GIT_REFLOG_ACTION=change-the-reflog git rebase --apply reflog-onto &&
+	GIT_REFLOG_ACTION=change-the-reflog git rebase reflog-onto &&
 	git log -g --format=%gs -3 >actual &&
 	cat >expect <<-\EOF &&
-	rebase finished: returning to refs/heads/reflog-prefix
-	change-the-reflog: reflog-to-rebase
-	change-the-reflog: checkout reflog-onto
+	change-the-reflog (finish): returning to refs/heads/reflog-prefix
+	change-the-reflog (pick): reflog-to-rebase
+	change-the-reflog (start): checkout reflog-onto
 	EOF
 	test_cmp expect actual
 '

base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
-- 
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