Korean fallback: spell 바탕 right, and choose the label's fallback style once

crates/compose/src/shape.rs

@@ -1169,8 +1169,9 @@ fn shape_segment(
     if let Some(label) = replacement.filter(|_| auto_leading.glyph_fallback) {
         let lang = designcraft_doc::language_tag(&p.language);
         let mut segments: Vec<(usize, usize, Arc<FontFace>)> = Vec::new();
+        // The same for every character of the label: worked out once, not per character.
+        let prefer_sans = designcraft_fonts::sans_by_name(&p.font_family).or_else(|| style_of_substitute(&face.family));
         for (at, c) in label.char_indices() {
-            let prefer_sans = designcraft_fonts::sans_by_name(&p.font_family).or_else(|| style_of_substitute(&face.family));
             let selected =
                 if face.covers(c) { face.clone() } else { db.fallback_for_styled(c, face.id(), lang, prefer_sans).unwrap_or_else(|| face.clone()) };
             if let Some((_, end, previous)) = segments.last_mut().filter(|(_, _, previous)| previous.id() == selected.id()) {

crates/fonts/src/fontdb/fallback.rs

@@ -120,12 +120,12 @@ pub fn sans_by_name(family: &str) -> Option<bool> {
     let has = |needles: &[&str]| needles.iter().any(|n| lower.contains(n));
     // A Korean serif name comes first: "Myungjo Gothic" does not exist, but a name holding both
     // reads as the serif it names, and "Sans" inside "Noto Sans Myungjo" would otherwise win.
-    if has(&["batang", "myungjo", "myeongjo", "gungsuh", "\u{BC14}\u{D5D5}", "\u{BA85}\u{C870}", "\u{AD81}\u{C11C}"]) {
+    if has(&["batang", "myungjo", "myeongjo", "gungsuh", "\u{BC14}\u{D0D5}", "\u{BA85}\u{C870}", "\u{AD81}\u{C11C}"]) {
         return Some(false);
     }
     // Then the word itself, which outranks every sans indicator: "Sweet Gothic Serif" is a serif
     // family whatever "Gothic" suggests. "Sans serif" and "sans-serif" end with the word and do
-    // not mean it, so the phrase goes before the word is looked for (both noted in review).
+    // not mean it, so the phrase goes before the word is looked for.
     if lower.replace("sans-serif", "sans").replace("sans serif", "sans").contains("serif") {
         return Some(false);
     }

crates/fonts/src/fontdb/tests/fallback.rs

@@ -178,7 +178,7 @@ fn a_korean_family_name_says_sans_or_serif() {
 
 /// "sans serif" ends with the word it is not. The bare "serif" needle matched first, so
 /// "Microsoft Sans Serif" -- and the CSS generic -- classified as serif and a missing Hangul
-/// glyph took the serif-first chain (noted in review of #1692).
+/// glyph took the serif-first chain (#1692).
 #[test]
 fn a_sans_serif_name_is_not_read_as_serif() {
     for sans in ["sans-serif", "Microsoft Sans Serif", "MS Sans Serif", "Lucida Sans Serif"] {
@@ -192,10 +192,15 @@ fn a_sans_serif_name_is_not_read_as_serif() {
     assert_eq!(sans_by_name("Noto Sans Myungjo"), Some(false));
     assert_eq!(sans_by_name("Myungjo Gothic"), Some(false));
     // And the word outranks every sans indicator: Sweet Gothic Serif is a serif family
-    // whatever "Gothic" suggests (noted in review).
+    // whatever "Gothic" suggests.
     for serif in ["Sweet Gothic Serif", "Gothic Serif", "Sans Forgetica Serif"] {
         assert_eq!(sans_by_name(serif), Some(false), "{serif} names itself serif");
     }
+    // Korean serif names written in Hangul: 바탕 (Batang), 명조 (Myungjo), 궁서 (Gungsuh). 바탕 was
+    // spelled with the wrong second syllable, so a Hangul Batang name was not recognised.
+    for serif in ["\u{BC14}\u{D0D5}\u{CCB4}", "HCR \u{BC14}\u{D0D5}", "\u{D55C}\u{CEF4} \u{BA85}\u{C870}", "\u{AD81}\u{C11C}\u{CCB4}"] {
+        assert_eq!(sans_by_name(serif), Some(false), "{serif} is serif");
+    }
     // Neither word present, so the caller still decides.
     assert_eq!(sans_by_name("monospace"), None);
     assert_eq!(sans_by_name("system-ui"), None);