From 428bc0168f25309e11e6f515cb9a88b78863e392 Mon Sep 17 00:00:00 2001
From: Rod S <rsheeter@google.com>
Date: Sat, 4 Jan 2025 21:10:19 +0100
Subject: [PATCH] Obey source OS/2 family class

---
 fontbe/src/os2.rs                                      | 2 ++
 fontc/src/lib.rs                                       | 7 +++++++
 fontir/src/ir.rs                                       | 5 +++++
 resources/testdata/FontInfo-Regular.ufo/fontinfo.plist | 5 +++++
 ufo2fontir/src/source.rs                               | 5 +++++
 5 files changed, 24 insertions(+)

diff --git a/fontbe/src/os2.rs b/fontbe/src/os2.rs
index 37965e129..6ac6fcfef 100644
--- a/fontbe/src/os2.rs
+++ b/fontbe/src/os2.rs
@@ -566,6 +566,8 @@ impl Work<Context, AnyWorkId, Error> for Os2Work {
             // https://github.com/googlefonts/ufo2ft/blob/main/Lib/ufo2ft/outlineCompiler.py#L705
             us_break_char: Some(32),
 
+            s_family_class: static_metadata.misc.family_class.unwrap_or_default(),
+
             // Avoid "field must be present for version 2" caused by default to None
             us_default_char: Some(0),
             us_max_context: Some(0),
diff --git a/fontc/src/lib.rs b/fontc/src/lib.rs
index 487269e67..1d2d2cc3b 100644
--- a/fontc/src/lib.rs
+++ b/fontc/src/lib.rs
@@ -620,6 +620,13 @@ mod tests {
         );
     }
 
+    #[test]
+    fn compile_obeys_family_class() {
+        let result = TestCompile::compile_source("fontinfo.designspace");
+        let os2 = result.font().os2().unwrap();
+        assert_eq!(1 << 8 | 2, os2.s_family_class());
+    }
+
     #[test]
     fn compile_variable_simple_glyph_with_implied_oncurves() {
         let result = TestCompile::compile_source("glyphs3/Oswald-O.glyphs");
diff --git a/fontir/src/ir.rs b/fontir/src/ir.rs
index 5f27dd9b0..e1c709e88 100644
--- a/fontir/src/ir.rs
+++ b/fontir/src/ir.rs
@@ -129,6 +129,9 @@ pub struct MiscMetadata {
 
     pub created: Option<DateTime<Utc>>,
 
+    // <https://learn.microsoft.com/en-us/typography/opentype/spec/os2#sfamilyclass>
+    pub family_class: Option<i16>,
+
     pub panose: Option<Panose>,
 
     // Allows source to explicitly control bits. <https://github.com/googlefonts/fontc/issues/1027>
@@ -494,6 +497,7 @@ impl StaticMetadata {
                 // <https://github.com/googlefonts/ufo2ft/blob/0d2688cd847d003b41104534d16973f72ef26c40/Lib/ufo2ft/fontInfoData.py#L365>
                 head_flags: 3,
                 created: None,
+                family_class: None,
                 panose: None,
                 unicode_range_bits: None,
                 codepage_range_bits: None,
@@ -1957,6 +1961,7 @@ mod tests {
                 head_flags: 42,
                 lowest_rec_ppm: 42,
                 created: None,
+                family_class: None,
                 panose: None,
                 unicode_range_bits: None,
                 codepage_range_bits: None,
diff --git a/resources/testdata/FontInfo-Regular.ufo/fontinfo.plist b/resources/testdata/FontInfo-Regular.ufo/fontinfo.plist
index e75e8de16..28c32a4c6 100644
--- a/resources/testdata/FontInfo-Regular.ufo/fontinfo.plist
+++ b/resources/testdata/FontInfo-Regular.ufo/fontinfo.plist
@@ -34,5 +34,10 @@
     <integer>-290</integer>
     <key>openTypeHheaLineGap</key>
     <integer>43</integer>
+		<key>openTypeOS2FamilyClass</key>
+		<array>
+			<integer>1</integer>
+			<integer>2</integer>
+		</array>
   </dict>
 </plist>
diff --git a/ufo2fontir/src/source.rs b/ufo2fontir/src/source.rs
index 55de154d4..a3db7988a 100644
--- a/ufo2fontir/src/source.rs
+++ b/ufo2fontir/src/source.rs
@@ -869,6 +869,11 @@ impl Work<Context, WorkId, Error> for StaticMetadataWork {
             .map(|bit_indices| bit_indices.iter().map(|i| 1 << i).fold(0, |acc, e| acc | e))
             .unwrap_or(static_metadata.misc.head_flags);
 
+        static_metadata.misc.family_class = font_info_at_default
+            .open_type_os2_family_class
+            .as_ref()
+            .map(|v| (v.class_id as i16) << 8 | v.subclass_id as i16);
+
         static_metadata.misc.created =
             try_parse_date(font_info_at_default.open_type_head_created.as_ref())
                 .or(static_metadata.misc.created);