More small tweaks

Author: LaurenzV

src/cff2.rs

@@ -9,7 +9,8 @@ pub fn subset(ctx: &mut Context) -> crate::Result<()> {
 
     let result = glyf::subset_with(ctx, |old_gid, ctx| {
         let data = match &ctx.interjector {
-            Interjector::Dummy => return Err(Unimplemented),
+            // We reject CFF2 fonts earlier if `variable_fonts` feature is not enabled.
+            Interjector::Dummy => unreachable!(),
             #[cfg(feature = "variable_fonts")]
             Interjector::Skrifa(s) => {
                 Cow::Owned(s.glyph_data(&mut maxp_data, old_gid).ok_or(MalformedFont)?)

src/interjector.rs

@@ -136,6 +136,7 @@ pub(crate) mod skrifa {
             );
 
             for (_, _, quad) in cubic.to_quads(1e-2) {
+                // Note that `quad.p2` is the same as `quad.p0` of the next point in the iterator.
                 self.quad_to(
                     quad.p1.x as f32,
                     quad.p1.y as f32,

src/lib.rs

@@ -142,7 +142,7 @@ fn prepare_context<'a>(
     let _ = variation_coordinates;
 
     #[cfg(not(feature = "variable_fonts"))]
-    let interjector = Box::new(DummyInterjector);
+    let interjector = DummyInterjector;
     // For CFF, we _always_ want to do normal subsetting, since CFF cannot have variations.
     // For TrueType, we prefer normal subsetting in case no variation was requested. If we do have
     // variations, we use `skrifa` to instance.

tests/data/fonttools.tests

@@ -13,6 +13,7 @@ NotoSansCJKsc-Bold-subset1.otf;1
 NotoSans-Regular_var.ttf;10,40,58,201-205;wght=400
 NotoSans-Regular_var.ttf;10,40,58,201-205;wght=900
 NotoSans-Regular_var.ttf;10,40,58,201-205;wght=800,wdth=70.0
+// Note that the lsb values currently doesn't match fonttools
 Cantarell-VF.otf;1,15,30-35,40,103-105;wght=400
 Cantarell-VF.otf;1,15,30-35,40,103-105;wght=800