merge & sequencer: unify codepaths that write "Conflicts:" hint

Two identical loops in suggest_conflicts() in merge, and
do_recursive_merge() in sequencer, can use a single helper function
extracted from the latter that prepares the "Conflicts:" hint that
is meant to remind the user the paths for which merge conflicts had
to be resolved to write a better commit log message.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/merge.c

@@ -28,6 +28,7 @@
 #include "remote.h"
 #include "fmt-merge-msg.h"
 #include "gpg-interface.h"
+#include "sequencer.h"
 
 #define DEFAULT_TWOHEAD (1<<0)
 #define DEFAULT_OCTOPUS (1<<1)
@@ -888,24 +889,15 @@ static int suggest_conflicts(void)
 {
 	const char *filename;
 	FILE *fp;
-	int pos;
+	struct strbuf msgbuf = STRBUF_INIT;
 
 	filename = git_path("MERGE_MSG");
 	fp = fopen(filename, "a");
 	if (!fp)
 		die_errno(_("Could not open '%s' for writing"), filename);
-	fprintf(fp, "\nConflicts:\n");
-	for (pos = 0; pos < active_nr; pos++) {
-		const struct cache_entry *ce = active_cache[pos];
-
-		if (ce_stage(ce)) {
-			fprintf(fp, "\t%s\n", ce->name);
-			while (pos + 1 < active_nr &&
-					!strcmp(ce->name,
-						active_cache[pos + 1]->name))
-				pos++;
-		}
-	}
+
+	append_conflicts_hint(&msgbuf);
+	fputs(msgbuf.buf, fp);
 	fclose(fp);
 	rerere(allow_rerere_auto);
 	printf(_("Automatic merge failed; "

sequencer.c

@@ -287,6 +287,24 @@ static int fast_forward_to(const unsigned char *to, const unsigned char *from,
 	return ret;
 }
 
+void append_conflicts_hint(struct strbuf *msgbuf)
+{
+	int i;
+
+	strbuf_addstr(msgbuf, "\nConflicts:\n");
+	for (i = 0; i < active_nr;) {
+		const struct cache_entry *ce = active_cache[i++];
+		if (ce_stage(ce)) {
+			strbuf_addch(msgbuf, '\t');
+			strbuf_addstr(msgbuf, ce->name);
+			strbuf_addch(msgbuf, '\n');
+			while (i < active_nr && !strcmp(ce->name,
+							active_cache[i]->name))
+				i++;
+		}
+	}
+}
+
 static int do_recursive_merge(struct commit *base, struct commit *next,
 			      const char *base_label, const char *next_label,
 			      unsigned char *head, struct strbuf *msgbuf,
@@ -328,21 +346,8 @@ static int do_recursive_merge(struct commit *base, struct commit *next,
 	if (opts->signoff)
 		append_signoff(msgbuf, 0, 0);
 
-	if (!clean) {
-		int i;
-		strbuf_addstr(msgbuf, "\nConflicts:\n");
-		for (i = 0; i < active_nr;) {
-			const struct cache_entry *ce = active_cache[i++];
-			if (ce_stage(ce)) {
-				strbuf_addch(msgbuf, '\t');
-				strbuf_addstr(msgbuf, ce->name);
-				strbuf_addch(msgbuf, '\n');
-				while (i < active_nr && !strcmp(ce->name,
-						active_cache[i]->name))
-					i++;
-			}
-		}
-	}
+	if (!clean)
+		append_conflicts_hint(msgbuf);
 
 	return !clean;
 }

sequencer.h

@@ -51,5 +51,6 @@ int sequencer_pick_revisions(struct replay_opts *opts);
 extern const char sign_off_header[];
 
 void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag);
+void append_conflicts_hint(struct strbuf *msgbuf);
 
 #endif