From: Ben Harris <bjh21@bjh21.me.uk>
Date: Sat, 14 Dec 2024 16:41:51 +0000 (+0000)
Subject: compatcheck: detect vanished code points from fonts
X-Git-Tag: bedstead-3.251~72
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~bjharris/git?a=commitdiff_plain;h=5b758ec94c773183ce87289f7c4db46081b3e1e7;p=bedstead.git

compatcheck: detect vanished code points from fonts
---

diff --git a/compatcheck b/compatcheck
index e96e766..a11478f 100755
--- a/compatcheck
+++ b/compatcheck
@@ -24,5 +24,15 @@ if not (set(ttold.getGlyphOrder()) <= set(ttnew.getGlyphOrder())):
    fail("Glyphs vanished: "
         f"{set(ttold.getGlyphOrder()) - set(ttnew.getGlyphOrder())!r}")
 
+for cmapold in ttold['cmap'].tables:
+    cmapnew = ttnew['cmap'].getcmap(cmapold.platformID, cmapold.platEncID)
+    if cmapnew == None:
+        fail("No cmap in new font for "
+             f"{(cmapold.platformID,cmapold.platEncID)}")
+    elif not (set(cmapold.cmap.keys()) <= set(cmapnew.cmap.keys())):
+        fail("Code points vanished from "
+             f"{(cmapold.platformID,cmapold.platEncID)}: "
+             f"{set(cmapold.cmap.keys()) - set(cmapnew.cmap.keys())!r}")
+
 if failed:
     exit(1)