Fix #5714: doc comments on the width profile tests

crates/doc/src/appearance/profile.rs

@@ -395,6 +395,7 @@ pub struct SavedProfile {
 mod tests {
     use super::*;
 
+    /// Widths and steps are found by search, at the ends, between points and at a step.
     #[test]
     fn width_profile_lookups_by_search() {
         let p = WidthProfile { points: vec![(0.0, 0.0, 0.0), (0.5, 1.0, 1.0), (0.5, 0.5, 0.25), (1.0, 0.0, 0.0)] };
@@ -441,6 +442,7 @@ mod tests {
         }
     }
 
+    /// Neither side of a profile goes wider or narrower than the two points of the span it is in.
     #[test]
     fn widths_never_pass_the_points_either_side() {
         for preset in WidthProfile::PRESETS {
@@ -474,6 +476,7 @@ mod tests {
         assert!((p.at(0.25).0 - 2.0).abs() < 1e-12 && (p.at(0.75).0 - 1.5).abs() < 1e-12);
     }
 
+    /// `widest()` is at least the stroke's width anywhere along the profile, even where the sides peak apart.
     #[test]
     fn widest_covers_every_width_along_the_profile() {
         let profiles = [

crates/doc/src/appearance/tests.rs

@@ -192,6 +192,7 @@ fn strokes_without_pressure_round_trip_unchanged() {
     assert_eq!((st.pressure, st.tilt, st.bearing, st.rotation), (None, None, None, None));
 }
 
+/// The Lens profile's widths at its middle, a quarter of the way along and past its end.
 #[test]
 fn profile_interp() {
     let p = WidthProfile::lens();

crates/effects/src/stroke/tests.rs

@@ -225,6 +225,7 @@ fn expand_stroke_region_of_a_round_line_stays_compact() {
     assert_eq!(dense_anchors, anchors, "colinear spine points should not add outline anchors");
 }
 
+/// A line's outline takes its width profile, its dashes (each reading the profile where it sits) or neither.
 #[test]
 fn line_outline_uses_the_profile_dashes_or_a_plain_stroke() {
     let l = line(0.0, 100.0);

crates/effects/src/stroke/tests_gradient.rs

@@ -117,6 +117,7 @@ fn along_keeps_a_corners_colour_round_its_outside() {
     assert!((param(&sl, Point::new(95.0, 8.0)).unwrap() - 0.54).abs() < 1e-6);
 }
 
+/// An Across stroke gradient runs from the stroke's left edge to its right edge, also where a width profile moves them.
 #[test]
 fn across_runs_from_the_left_edge_to_the_right() {
     let st = stroke(10.0, StrokeGradientMode::Across);
@@ -163,6 +164,7 @@ fn an_aligned_stroke_spans_the_gradient_across_the_side_it_shows_on() {
     }
 }
 
+/// The gradient slices cover every point the stroke paints, with each join, caps, arrowheads, a profile and dashes.
 #[test]
 fn slices_cover_everything_the_stroke_paints() {
     let zig = poly(&[(0.0, 0.0), (60.0, 40.0), (0.0, 80.0), (70.0, 90.0), (75.0, 20.0)], false);

crates/effects/src/stroke/width.rs

@@ -423,6 +423,7 @@ mod tests {
         assert!((area(&width_outline(&line(), 10.0, &p, &capped(LineCap::Square), 0.01)) - 1100.0).abs() < 1e-6);
     }
 
+    /// The Lens outline swells on its curve, and a profile with one side at zero paints only the other side.
     #[test]
     fn lens_profile_swells_smoothly_and_one_sided_profiles_stay_on_their_side() {
         // Each half of the lens rises on a cubic from 0 to full width, flat at the middle: it

crates/engine/src/tests/outlinestroke.rs

@@ -71,6 +71,7 @@ fn arrowheads_are_part_of_the_outline() {
     assert_eq!(path_of(&n).subpaths.len(), 1, "line and head are one shape");
 }
 
+/// Outline Stroke of a Lens-profile line covers 7/12 of the full-width rectangle.
 #[test]
 fn a_lens_profile_outlines_to_seven_twelfths_of_the_rectangle() {
     let mut s = session();

crates/engine/src/tests/widthpoints.rs

@@ -214,6 +214,7 @@ fn new_width_point_without_adjoining_preserves_neighbours() {
     new_point_adjoining(false);
 }
 
+/// A new width point with Adjust Adjoining scales only its nearest neighbours, by the widths sampled where it goes.
 #[test]
 fn new_width_point_adjust_adjoining_uses_sampled_widths() {
     for indexed in [false, true] {