Fix and un-allow clippy::return_self_not_must_use lints (#773)

vello/src/lib.rs

@@ -101,7 +101,6 @@
     single_use_lifetimes,
     unnameable_types,
     unreachable_pub,
-    clippy::return_self_not_must_use,
     clippy::cast_possible_truncation,
     clippy::missing_assert_message,
     clippy::shadow_unrelated,

vello/src/scene.rs

@@ -369,6 +369,7 @@ impl<'a> DrawGlyphs<'a> {
     /// translation.
     ///
     /// The default value is the identity matrix.
+    #[must_use]
     pub fn transform(mut self, transform: Affine) -> Self {
         self.run.transform = Transform::from_kurbo(&transform);
         self
@@ -379,6 +380,7 @@ impl<'a> DrawGlyphs<'a> {
     /// an oblique font.
     ///
     /// The default value is `None`.
+    #[must_use]
     pub fn glyph_transform(mut self, transform: Option<Affine>) -> Self {
         self.run.glyph_transform = transform.map(|xform| Transform::from_kurbo(&xform));
         self
@@ -387,6 +389,7 @@ impl<'a> DrawGlyphs<'a> {
     /// Sets the font size in pixels per em units.
     ///
     /// The default value is 16.0.
+    #[must_use]
     pub fn font_size(mut self, size: f32) -> Self {
         self.run.font_size = size;
         self
@@ -395,12 +398,14 @@ impl<'a> DrawGlyphs<'a> {
     /// Sets whether to enable hinting.
     ///
     /// The default value is `false`.
+    #[must_use]
     pub fn hint(mut self, hint: bool) -> Self {
         self.run.hint = hint;
         self
     }
 
     /// Sets the normalized design space coordinates for a variable font instance.
+    #[must_use]
     pub fn normalized_coords(mut self, coords: &[NormalizedCoord]) -> Self {
         self.scene
             .encoding
@@ -419,6 +424,7 @@ impl<'a> DrawGlyphs<'a> {
     /// Sets the brush.
     ///
     /// The default value is solid black.
+    #[must_use]
     pub fn brush(mut self, brush: impl Into<BrushRef<'a>>) -> Self {
         self.brush = brush.into();
         self
@@ -427,6 +433,7 @@ impl<'a> DrawGlyphs<'a> {
     /// Sets an additional alpha multiplier for the brush.
     ///
     /// The default value is 1.0.
+    #[must_use]
     pub fn brush_alpha(mut self, alpha: f32) -> Self {
         self.brush_alpha = alpha;
         self

vello_encoding/src/clip.rs

@@ -65,6 +65,7 @@ impl ClipBic {
     /// operation, it represents doing the pops of `self`, the pushes of
     /// `self`, the pops of `other`, and the pushes of `other`. The middle
     /// two can cancel each other out.
+    #[must_use]
     pub fn combine(self, other: Self) -> Self {
         let m = self.b.min(other.a);
         Self::new(self.a + other.a - m, self.b + other.b - m)

vello_encoding/src/lib.rs

@@ -21,7 +21,6 @@
 #![expect(
     missing_debug_implementations,
     single_use_lifetimes,
-    clippy::return_self_not_must_use,
     clippy::cast_possible_truncation,
     clippy::missing_assert_message,
     clippy::missing_panics_doc,

vello_encoding/src/monoid.rs

@@ -11,5 +11,6 @@ pub trait Monoid: Default {
     fn new(value: Self::SourceValue) -> Self;
 
     /// Combines two monoids. This operation must be associative.
+    #[must_use]
     fn combine(&self, other: &Self) -> Self;
 }