Re: [PATCH 16/22] sequencer: prepare for rebase -i's GPG settings

This patch teaches the sequencer that trick, as part of the bigger
effort to make the sequencer the work horse of the interactive rebase.

Signed-off-by: Johannes Schindelin <redacted>
---
 sequencer.c | 48 +++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 43 insertions(+), 5 deletions(-)

diff --git a/sequencer.c b/sequencer.c
index 4204cc8..e094ac2 100644
--- a/sequencer.c
+++ b/sequencer.c

@@ -15,6 +15,7 @@
 #include "merge-recursive.h"
 #include "refs.h"
 #include "argv-array.h"
+#include "quote.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 

@@ -33,6 +34,11 @@ static GIT_PATH_FUNC(git_path_head_file, "sequencer/head")
  * being rebased.
  */
 static GIT_PATH_FUNC(rebase_path_author_script, "rebase-merge/author-script")
+/*
+ * The following files are written by git-rebase just after parsing the
+ * command-line (and are only consumed, not modified, by the sequencer).
+ */

 
 /* We will introduce the 'interactive rebase' mode later */
 #define IS_REBASE_I() 0

@@ -129,6 +135,16 @@ static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
 	return 1;
 }
 
+static const char *gpg_sign_opt_quoted(struct replay_opts *opts)
+{
+	static struct strbuf buf = STRBUF_INIT;
+
+	strbuf_reset(&buf);
+	if (opts->gpg_sign)
+		sq_quotef(&buf, "-S%s", opts->gpg_sign);
+	return buf.buf;
+}

+
 void *sequencer_entrust(struct replay_opts *opts, void *set_me_free_after_use)
 {
 	ALLOC_GROW(opts->owned, opts->owned_nr + 1, opts->owned_alloc);

@@ -471,17 +487,20 @@ int sequencer_commit(const char *defmsg, struct replay_opts *opts,
 
 	if (IS_REBASE_I()) {
 		env = read_author_script();
-		if (!env)
+		if (!env) {
+			const char *gpg_opt = gpg_sign_opt_quoted(opts);
+
 			return error("You have staged changes in your working "
 				"tree. If these changes are meant to be\n"
 				"squashed into the previous commit, run:\n\n"
-				"  git commit --amend $gpg_sign_opt_quoted\n\n"

 	}
 
 	argv_array_init(&array);

@@ -955,8 +974,27 @@ static int populate_opts_cb(const char *key, const char *value, void *data)
 
 static int read_populate_opts(struct replay_opts *opts)
 {
-	if (IS_REBASE_I())
+	if (IS_REBASE_I()) {
+		struct strbuf buf = STRBUF_INIT;
+
+		if (read_oneliner(&buf, rebase_path_gpg_sign_opt(), 1)) {
+			if (buf.len && buf.buf[buf.len - 1] == '\n') {
+				if (--buf.len &&
+				    buf.buf[buf.len - 1] == '\r')
+					buf.len--;
+				buf.buf[buf.len] = '\0';
+			}