rerere: refactor "replay" part of do_plain_rerere()

Extract the body of a loop that attempts to replay recorded
resolution for each conflicted path into a helper function, not
because I want to call it from multiple places later, but because
the logic has become too deeply nested and hard to read.

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

rerere.c

@@ -629,6 +629,44 @@ static void update_paths(struct string_list *update)
 		rollback_lock_file(&index_lock);
 }
 
+/*
+ * The path indicated by rr_item may still have conflict for which we
+ * have a recorded resolution, in which case replay it and optionally
+ * update it.  Or it may have been resolved by the user and we may
+ * only have the preimage for that conflict, in which case the result
+ * needs to be recorded as a resolution in a postimage file.
+ */
+static void do_rerere_one_path(struct string_list_item *rr_item,
+			       struct string_list *update)
+{
+	const char *path = rr_item->string;
+	const char *name = (const char *)rr_item->util;
+
+	/* Is there a recorded resolution we could attempt to apply? */
+	if (has_rerere_resolution(name)) {
+		if (merge(name, path))
+			return; /* failed to replay */
+
+		if (rerere_autoupdate)
+			string_list_insert(update, path);
+		else
+			fprintf(stderr,
+				"Resolved '%s' using previous resolution.\n",
+				path);
+		goto mark_resolved;
+	}
+
+	/* Let's see if the user has resolved it. */
+	if (handle_file(path, NULL, NULL))
+		return; /* not yet resolved */
+
+	copy_file(rerere_path(name, "postimage"), path, 0666);
+	fprintf(stderr, "Recorded resolution for '%s'.\n", path);
+mark_resolved:
+	free(rr_item->util);
+	rr_item->util = NULL;
+}
+
 static int do_plain_rerere(struct string_list *rr, int fd)
 {
 	struct string_list conflict = STRING_LIST_INIT_DUP;
@@ -682,41 +720,8 @@ static int do_plain_rerere(struct string_list *rr, int fd)
 		}
 	}
 
-	/*
-	 * Some of the paths that had conflicts earlier might have
-	 * been resolved by the user.  Others may be similar to a
-	 * conflict already that was resolved before.
-	 */
-	for (i = 0; i < rr->nr; i++) {
-		int ret;
-		const char *path = rr->items[i].string;
-		const char *name = (const char *)rr->items[i].util;
-
-		/* Is there a recorded resolution we could attempt to apply? */
-		if (has_rerere_resolution(name)) {
-			if (merge(name, path))
-				continue;
-
-			if (rerere_autoupdate)
-				string_list_insert(&update, path);
-			else
-				fprintf(stderr,
-					"Resolved '%s' using previous resolution.\n",
-					path);
-			goto mark_resolved;
-		}
-
-		/* Let's see if the user has resolved it. */
-		ret = handle_file(path, NULL, NULL);
-		if (ret)
-			continue;
-
-		copy_file(rerere_path(name, "postimage"), path, 0666);
-		fprintf(stderr, "Recorded resolution for '%s'.\n", path);
-	mark_resolved:
-		free(rr->items[i].util);
-		rr->items[i].util = NULL;
-	}
+	for (i = 0; i < rr->nr; i++)
+		do_rerere_one_path(&rr->items[i], &update);
 
 	if (update.nr)
 		update_paths(&update);