Remove HalfEdgeBuilder::replace_surface

Thanks to the recent simplifications, it was no longer carrying its
weight.

crates/fj-kernel/src/algorithms/sweep/edge.rs

@@ -196,8 +196,10 @@ mod tests {
                 half_edge
             };
             let side_up = {
-                let mut side_up = PartialHalfEdge::default();
+                let mut side_up = PartialHalfEdge {
-                side_up.replace_surface(surface.clone());
+                    surface: surface.clone(),
+                    ..Default::default()
+                };
 
                 {
                     let [back, front] = side_up
@@ -217,8 +219,10 @@ mod tests {
                 side_up
             };
             let top = {
-                let mut top = PartialHalfEdge::default();
+                let mut top = PartialHalfEdge {
-                top.replace_surface(surface.clone());
+                    surface: surface.clone(),
+                    ..Default::default()
+                };
 
                 {
                     let [(back, back_surface), (front, front_surface)] =
@@ -243,8 +247,10 @@ mod tests {
                 .clone()
             };
             let side_down = {
-                let mut side_down = PartialHalfEdge::default();
+                let mut side_down = PartialHalfEdge {
-                side_down.replace_surface(surface);
+                    surface,
+                    ..Default::default()
+                };
 
                 let [(back, back_surface), (front, front_surface)] =
                     side_down.vertices.each_mut_ext();

crates/fj-kernel/src/builder/cycle.rs

@@ -149,7 +149,7 @@ impl CycleBuilder for PartialCycle {
 
             let [_, vertex] = &mut new_half_edge.vertices;
             vertex.1 = shared_surface_vertex;
-            new_half_edge.replace_surface(self.surface.clone());
+            new_half_edge.surface = self.surface.clone();
             new_half_edge.infer_global_form();
         }
 

crates/fj-kernel/src/builder/edge.rs

@@ -11,16 +11,6 @@ use super::CurveBuilder;
 
 /// Builder API for [`PartialHalfEdge`]
 pub trait HalfEdgeBuilder {
-    /// Completely replace the surface in this half-edge's object graph
-    ///
-    /// Please note that this operation will write to both vertices that the
-    /// half-edge references. If any of them were created from full objects,
-    /// this will break the connection to those, meaning that building the
-    /// partial objects won't result in those full objects again. This will be
-    /// the case, even if those full objects already referenced the provided
-    /// surface.
-    fn replace_surface(&mut self, surface: impl Into<Partial<Surface>>);
-
     /// Update partial half-edge to be a circle, from the given radius
     fn update_as_circle_from_radius(&mut self, radius: impl Into<Scalar>);
 
@@ -61,12 +51,6 @@ pub trait HalfEdgeBuilder {
 }
 
 impl HalfEdgeBuilder for PartialHalfEdge {
-    fn replace_surface(&mut self, surface: impl Into<Partial<Surface>>) {
-        let surface = surface.into();
-
-        self.surface = surface;
-    }
-
     fn update_as_circle_from_radius(&mut self, radius: impl Into<Scalar>) {
         let path = self.curve.write().update_as_circle_from_radius(radius);
 
@@ -130,7 +114,7 @@ impl HalfEdgeBuilder for PartialHalfEdge {
         surface: impl Into<Partial<Surface>>,
         points: [impl Into<Point<2>>; 2],
     ) {
-        self.replace_surface(surface.into());
+        self.surface = surface.into();
 
         for (vertex, point) in self.vertices.each_mut_ext().zip_ext(points) {
             let mut surface_form = vertex.1.write();

crates/fj-operations/src/sketch.rs

@@ -30,8 +30,10 @@ impl Shape for fj::Sketch {
                 let half_edge = {
                     let surface = Partial::from(surface);
 
-                    let mut half_edge = PartialHalfEdge::default();
+                    let mut half_edge = PartialHalfEdge {
-                    half_edge.replace_surface(surface);
+                        surface,
+                        ..Default::default()
+                    };
                     half_edge.update_as_circle_from_radius(circle.radius());
 
                     Partial::from_partial(half_edge)