Derive PartialEq for Stroke, common derives for StrokeOpts. (#379)

As discussed in
https://xi.zulipchat.com/#narrow/stream/260979-kurbo/topic/PartialEq.20for.20Stroke.3F

Author: waywardmonkeys

CHANGELOG.md

@@ -15,6 +15,10 @@ You can find its changes [documented below](#0111-2024-09-12).
 
 This release has an [MSRV][] of 1.65.
 
+### Changed
+
+- `Stroke` is now `PartialEq`, `StrokeOpts` is now `Clone`, `Copy`, `Debug`, `Eq`, `PartialEq`. ([#379] by [@waywardmonkeys])
+
 ## [0.11.1][] (2024-09-12)
 
 This release has an [MSRV][] of 1.65.
@@ -75,6 +79,7 @@ Note: A changelog was not kept for or before this release
 [#370]: https://github.com/linebender/kurbo/pull/370
 [#375]: https://github.com/linebender/kurbo/pull/375
 [#376]: https://github.com/linebender/kurbo/pull/376
+[#379]: https://github.com/linebender/kurbo/pull/379
 
 [Unreleased]: https://github.com/linebender/kurbo/compare/v0.11.1...HEAD
 [0.11.0]: https://github.com/linebender/kurbo/releases/tag/v0.11.0

src/stroke.rs

@@ -42,7 +42,7 @@ pub enum Cap {
 }
 
 /// Describes the visual style of a stroke.
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 #[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Stroke {
@@ -63,11 +63,13 @@ pub struct Stroke {
 }
 
 /// Options for path stroking.
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub struct StrokeOpts {
     opt_level: StrokeOptLevel,
 }
 
 /// Optimization level for computing
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum StrokeOptLevel {
     /// Adaptively subdivide segments in half.
     Subdivide,
@@ -201,10 +203,10 @@ pub fn stroke(
     tolerance: f64,
 ) -> BezPath {
     if style.dash_pattern.is_empty() {
-        stroke_undashed(path, style, tolerance, opts)
+        stroke_undashed(path, style, tolerance, *opts)
     } else {
         let dashed = dash(path.into_iter(), style.dash_offset, &style.dash_pattern);
-        stroke_undashed(dashed, style, tolerance, opts)
+        stroke_undashed(dashed, style, tolerance, *opts)
     }
 }
 
@@ -213,7 +215,7 @@ fn stroke_undashed(
     path: impl IntoIterator<Item = PathEl>,
     style: &Stroke,
     tolerance: f64,
-    opts: &StrokeOpts,
+    opts: StrokeOpts,
 ) -> BezPath {
     let mut ctx = StrokeCtx {
         join_thresh: 2.0 * tolerance / style.width,
@@ -307,7 +309,7 @@ fn extend_reversed(out: &mut BezPath, elements: &[PathEl]) {
     }
 }
 
-fn fit_with_opts(co: &CubicOffset, tolerance: f64, opts: &StrokeOpts) -> BezPath {
+fn fit_with_opts(co: &CubicOffset, tolerance: f64, opts: StrokeOpts) -> BezPath {
     match opts.opt_level {
         StrokeOptLevel::Subdivide => fit_to_bezpath(co, tolerance),
         StrokeOptLevel::Optimized => fit_to_bezpath_opt(co, tolerance),
@@ -428,7 +430,7 @@ impl StrokeCtx {
         self.last_pt = p1;
     }
 
-    fn do_cubic(&mut self, style: &Stroke, c: CubicBez, tolerance: f64, opts: &StrokeOpts) {
+    fn do_cubic(&mut self, style: &Stroke, c: CubicBez, tolerance: f64, opts: StrokeOpts) {
         // First, detect degenerate linear case
 
         // Ordinarily, this is the direction of the chord, but if the chord is very