From c38d55614af0226be8eb3f3e1500da8b7be2fec8 Mon Sep 17 00:00:00 2001
From: Laurenz <laurmaedje@gmail.com>
Date: Fri, 9 Dec 2022 21:22:23 +0100
Subject: [PATCH] A few math fixes

---
 library/src/math/mod.rs   |  3 ++-
 library/src/math/tex.rs   | 12 +++++++-----
 src/syntax/kind.rs        | 10 +++++++++-
 src/syntax/parser.rs      | 10 +++++++---
 tests/typ/math/syntax.typ |  4 ++++
 5 files changed, 29 insertions(+), 10 deletions(-)

diff --git a/library/src/math/mod.rs b/library/src/math/mod.rs
index 62432b128..317bc1d4e 100644
--- a/library/src/math/mod.rs
+++ b/library/src/math/mod.rs
@@ -61,7 +61,8 @@ impl Layout for MathNode {
     ) -> SourceResult<Fragment> {
         let mut t = Texifier::new(styles);
         self.texify(&mut t)?;
-        layout_tex(vt, &t.finish(), self.display, styles)
+        Ok(layout_tex(vt, &t.finish(), self.display, styles)
+            .unwrap_or(Fragment::frame(Frame::new(Size::zero()))))
     }
 }
 
diff --git a/library/src/math/tex.rs b/library/src/math/tex.rs
index f17134b79..60f002498 100644
--- a/library/src/math/tex.rs
+++ b/library/src/math/tex.rs
@@ -14,7 +14,7 @@ pub fn layout_tex(
     tex: &str,
     display: bool,
     styles: StyleChain,
-) -> SourceResult<Fragment> {
+) -> Result<Fragment, &'static str> {
     // Load the font.
     let variant = variant(styles);
     let world = vt.world();
@@ -27,11 +27,13 @@ pub fn layout_tex(
     }
 
     // Prepare the font context.
-    let font = font.expect("failed to find suitable math font");
-    let ctx = font
+    let Some(font) = font else { return Err("failed to find suitable math font") };
+    let Some(ctx) = font
         .math()
         .map(|math| FontContext::new(font.ttf(), math))
-        .expect("failed to create font context");
+    else {
+        return Err("failed to create math font context");
+    };
 
     // Layout the formula.
     let em = styles.get(TextNode::SIZE);
@@ -45,7 +47,7 @@ pub fn layout_tex(
             Error::Layout(LayoutError::Font(err)) => err.to_string(),
         })
     else {
-        panic!("failed to layout with rex: {tex}");
+        return Err("failed to layout math");
     };
 
     // Determine the metrics.
diff --git a/src/syntax/kind.rs b/src/syntax/kind.rs
index d5fda7f8a..d29808d3e 100644
--- a/src/syntax/kind.rs
+++ b/src/syntax/kind.rs
@@ -405,7 +405,15 @@ impl SyntaxKind {
             Self::EnumNumbering(_) => "enumeration item numbering",
             Self::DescItem => "description list item",
             Self::Math => "math formula",
-            Self::Atom(_) => "math atom",
+            Self::Atom(s) => match s.as_str() {
+                "(" => "opening paren",
+                ")" => "closing paren",
+                "{" => "opening brace",
+                "}" => "closing brace",
+                "[" => "opening bracket",
+                "]" => "closing bracket",
+                _ => "math atom",
+            },
             Self::Script => "script",
             Self::Frac => "fraction",
             Self::AlignPoint => "alignment point",
diff --git a/src/syntax/parser.rs b/src/syntax/parser.rs
index 3e133fe12..a0b1e7d1e 100644
--- a/src/syntax/parser.rs
+++ b/src/syntax/parser.rs
@@ -338,9 +338,13 @@ impl<'s> Parser<'s> {
             Some(SyntaxKind::RightParen) => self.inside(Group::Paren),
             Some(SyntaxKind::Star) => self.inside(Group::Strong),
             Some(SyntaxKind::Underscore) => self.inside(Group::Emph),
-            Some(SyntaxKind::Dollar) => {
-                self.groups.last().map(|group| group.kind) == Some(Group::Math)
-            }
+            Some(SyntaxKind::Dollar) => self
+                .groups
+                .iter()
+                .rev()
+                .skip_while(|group| matches!(group.kind, Group::MathRow(..)))
+                .next()
+                .map_or(false, |group| group.kind == Group::Math),
             Some(SyntaxKind::Semicolon) => self.inside(Group::Expr),
             Some(SyntaxKind::From) => self.inside(Group::Imports),
             Some(SyntaxKind::Atom(s)) => match s.as_str() {
diff --git a/tests/typ/math/syntax.typ b/tests/typ/math/syntax.typ
index 79c306a25..4500d91ed 100644
--- a/tests/typ/math/syntax.typ
+++ b/tests/typ/math/syntax.typ
@@ -22,3 +22,7 @@ $ 1 + 2 = #{1 + 2} $
 $ A sub:eq:not B $
 ```
 <table>
+
+---
+// Error: 8 expected closing paren
+$ sum_( $