Math tests

11 files changed, 25 insertions, 22 deletions

diff --git a/library/src/math/ctx.rs b/library/src/math/ctx.rs
index fafb96f2..d682746e 100644
--- a/library/src/math/ctx.rs
+++ b/library/src/math/ctx.rs
@@ -23,7 +23,7 @@ macro_rules! percent {
 }
 
 /// The context for math layout.
-pub(super) struct MathContext<'a, 'b, 'v> {
+pub struct MathContext<'a, 'b, 'v> {
     pub vt: &'v mut Vt<'b>,
     pub regions: Regions<'a>,
     pub font: &'a Font,
diff --git a/library/src/math/lr.rs b/library/src/math/delimited.rs
index cdd5718c..cdd5718c 100644
--- a/library/src/math/lr.rs
+++ b/library/src/math/delimited.rs
diff --git a/library/src/math/frac.rs b/library/src/math/frac.rs
index ebdb5c02..9f7fb9d0 100644
--- a/library/src/math/frac.rs
+++ b/library/src/math/frac.rs
@@ -1,5 +1,7 @@
 use super::*;
 
+const FRAC_AROUND: Em = Em::new(0.1);
+
 /// # Fraction
 /// A mathematical fraction.
 ///
@@ -130,7 +132,7 @@ fn layout(
     let denom = ctx.layout_frame(denom)?;
     ctx.unstyle();
 
-    let around = Em::new(0.1).scaled(ctx);
+    let around = FRAC_AROUND.scaled(ctx);
     let num_gap = (shift_up - axis - num.descent()).max(num_min + thickness / 2.0);
     let denom_gap = (shift_down + axis - denom.ascent()).max(denom_min + thickness / 2.0);
 
diff --git a/library/src/math/fragment.rs b/library/src/math/fragment.rs
index fe9642a2..bef3f578 100644
--- a/library/src/math/fragment.rs
+++ b/library/src/math/fragment.rs
@@ -1,7 +1,7 @@
 use super::*;
 
 #[derive(Debug, Clone)]
-pub(super) enum MathFragment {
+pub enum MathFragment {
     Glyph(GlyphFragment),
     Variant(VariantFragment),
     Frame(FrameFragment),
@@ -118,7 +118,7 @@ impl From<Frame> for MathFragment {
 }
 
 #[derive(Debug, Clone, Copy)]
-pub(super) struct GlyphFragment {
+pub struct GlyphFragment {
     pub id: GlyphId,
     pub c: char,
     pub lang: Lang,
diff --git a/library/src/math/matrix.rs b/library/src/math/matrix.rs
index 527cf315..5f448901 100644
--- a/library/src/math/matrix.rs
+++ b/library/src/math/matrix.rs
@@ -1,7 +1,7 @@
 use super::*;
 
 const ROW_GAP: Em = Em::new(0.5);
-const COL_GAP: Em = Em::new(0.75);
+const COL_GAP: Em = Em::new(0.5);
 const VERTICAL_PADDING: Ratio = Ratio::new(0.1);
 
 /// # Vector
diff --git a/library/src/math/mod.rs b/library/src/math/mod.rs
index ab1fab13..4e60faca 100644
--- a/library/src/math/mod.rs
+++ b/library/src/math/mod.rs
@@ -5,29 +5,29 @@ mod ctx;
 mod accent;
 mod align;
 mod attach;
+mod delimited;
 mod frac;
 mod fragment;
-mod lr;
 mod matrix;
 mod op;
 mod root;
 mod row;
 mod spacing;
-mod stack;
 mod stretch;
 mod style;
 mod symbols;
+mod underover;
 
 pub use self::accent::*;
 pub use self::align::*;
 pub use self::attach::*;
+pub use self::delimited::*;
 pub use self::frac::*;
-pub use self::lr::*;
 pub use self::matrix::*;
 pub use self::op::*;
 pub use self::root::*;
-pub use self::stack::*;
 pub use self::style::*;
+pub use self::underover::*;
 
 use ttf_parser::{GlyphId, Rect};
 use typst::font::Font;
@@ -230,7 +230,7 @@ impl Layout for FormulaNode {
 impl Inline for FormulaNode {}
 
 #[capability]
-trait LayoutMath {
+pub trait LayoutMath {
     fn layout_math(&self, ctx: &mut MathContext) -> SourceResult<()>;
 }
 
diff --git a/library/src/math/root.rs b/library/src/math/root.rs
index d348ecc1..2d27bb11 100644
--- a/library/src/math/root.rs
+++ b/library/src/math/root.rs
@@ -1,5 +1,7 @@
 use super::*;
 
+const MIN_INDEX_SHIFT: Em = Em::new(0.35);
+
 /// # Square Root
 /// A square root.
 ///
@@ -126,7 +128,7 @@ fn layout(
 
     if let Some(index) = &index {
         sqrt_offset = kern_before + index.width() + kern_after;
-        shift_up.set_max(index.descent() + Em::new(0.35).scaled(ctx));
+        shift_up.set_max(index.descent() + MIN_INDEX_SHIFT.scaled(ctx));
         ascent.set_max(shift_up + index.ascent());
     }
 
diff --git a/library/src/math/row.rs b/library/src/math/row.rs
index d971ce22..e66fc18e 100644
--- a/library/src/math/row.rs
+++ b/library/src/math/row.rs
@@ -2,8 +2,10 @@ use crate::layout::AlignNode;
 
 use super::*;
 
+pub const TIGHT_LEADING: Em = Em::new(0.25);
+
 #[derive(Debug, Default, Clone)]
-pub(super) struct MathRow(pub Vec<MathFragment>);
+pub struct MathRow(pub Vec<MathFragment>);
 
 impl MathRow {
     pub fn new() -> Self {
@@ -85,8 +87,12 @@ impl MathRow {
     ) -> Frame {
         if self.0.iter().any(|frag| matches!(frag, MathFragment::Linebreak)) {
             let fragments = std::mem::take(&mut self.0);
+            let leading = if ctx.style.size >= MathSize::Text {
+                ctx.styles().get(ParNode::LEADING)
+            } else {
+                TIGHT_LEADING.scaled(ctx)
+            };
 
-            let leading = ctx.styles().get(ParNode::LEADING) * ctx.style.size.factor(ctx);
             let rows: Vec<_> = fragments
                 .split(|frag| matches!(frag, MathFragment::Linebreak))
                 .map(|slice| Self(slice.to_vec()))
diff --git a/library/src/math/spacing.rs b/library/src/math/spacing.rs
index 7083c5e1..fad1c863 100644
--- a/library/src/math/spacing.rs
+++ b/library/src/math/spacing.rs
@@ -24,11 +24,8 @@ pub(super) fn spacing(
 ) -> Em {
     use MathClass::*;
     let script = style.size <= MathSize::Script;
-    let (Some(l), Some(r)) = (left.class(), right.class()) else {
-        return ZERO;
-    };
-
-    match (l, r) {
+    let class = |frag: &MathFragment| frag.class().unwrap_or(Special);
+    match (class(left), class(right)) {
         // No spacing before punctuation; thin spacing after punctuation, unless
         // in script size.
         (_, Punctuation) => ZERO,
diff --git a/library/src/math/style.rs b/library/src/math/style.rs
index b3f3d8df..da2e2313 100644
--- a/library/src/math/style.rs
+++ b/library/src/math/style.rs
@@ -443,10 +443,6 @@ pub(super) fn styled_char(style: MathStyle, c: char) -> char {
         '∂' | 'ϵ' | 'ϑ' | 'ϰ' | 'ϕ' | 'ϱ' | 'ϖ'
     ));
 
-    if c == '-' {
-        return '−';
-    }
-
     if let Some(c) = latin_exception(c, variant, bold, italic) {
         return c;
     }
diff --git a/library/src/math/stack.rs b/library/src/math/underover.rs
index 3a47059c..3a47059c 100644
--- a/library/src/math/stack.rs
+++ b/library/src/math/underover.rs