From 1be864fb48a7c0bbe2843a5e341bccbe2d1c09da Mon Sep 17 00:00:00 2001
From: Ben Harris <bjh21@bjh21.me.uk>
Date: Thu, 2 Jan 2025 00:53:02 +0000
Subject: [PATCH] Don't emit AlternateSets that will be overridden

Just in case TTX changes its behaviour in this area in the future.
---
 bedstead.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/bedstead.c b/bedstead.c
index 1bfe8a5..c25e3e8 100644
--- a/bedstead.c
+++ b/bedstead.c
@@ -3668,7 +3668,7 @@ dogsub(void)
 static void
 doaltsubs(int noverrides, const struct alt_sub_override overrides[noverrides])
 {
-	int i, j;
+	int i, j, next_override = 0;
 
 	for (i = 1; i < nglyphs; i++) {
 #define HASDOT(x) (strchr(glyphs_by_name[x]->name, '.') != NULL)
@@ -3680,15 +3680,22 @@ doaltsubs(int noverrides, const struct alt_sub_override overrides[noverrides])
 		 * name comes immediately after the unqualified one.
 		 */
 		if (HASDOT(i)) {
-			printf("      <AlternateSet glyph='%s'>",
+			bool overridden = next_override < noverrides &&
+				strcmp(glyphs_by_name[i-1]->name,
+				       overrides[next_override].base) == 0;
+			printf("      %s<AlternateSet glyph='%s'>",
+			       overridden ? "<!-- " : "",
 			       glyphs_by_name[i-1]->name);
 			for (; i < nglyphs && HASDOT(i); i++)
 				printf("<Alternate glyph='%s'/>",
 				       glyphs_by_name[i]->name);
-			printf("</AlternateSet>\n");
+			printf("</AlternateSet>%s\n",
+			       overridden ? " -->" : "");
+			next_override += overridden;
 		}
 	}
 
+	printf("      <!-- overrides -->\n");
 	for (i = 0; i < noverrides; i++) {
 		printf("      <AlternateSet glyph='%s'>", overrides[i].base);
 		for (j = 0; j < MAX_ALT_SUB_OVERRIDE &&
-- 
2.30.2