Documents: nested code tags stay literal; an indented \[ formula is block

Co-Authored-By: Claude <noreply@anthropic.com>

src/documents/markdown/tex.rs

@@ -72,7 +72,8 @@ pub(super) fn swapped<'a>(text: &'a str, options: &ParseOptions) -> Swapped<'a>
 fn keep(container: &mdast::Node, text: &str, kept: &mut [bool]) {
     let mut nodes = Vec::new();
     walk(container, &mut nodes);
-    let mut code: Option<(String, usize)> = None;
+    // Open code tags, and where the outermost one's text starts.
+    let (mut open, mut from) = (Vec::new(), 0);
     for node in &nodes[1..] {
         use mdast::Node::*;
         let whole = span(node);
@@ -96,22 +97,26 @@ fn keep(container: &mdast::Node, text: &str, kept: &mut [bool]) {
                 let Some(tag) = html::tag(&text[whole.clone()]) else {
                     continue;
                 };
-                match &code {
-                    Some((name, from)) if tag.closing && tag.name == *name => {
-                        kept[*from..whole.start].fill(true);
-                        code = None;
+                if html::inline_style(&tag.name) != Some(Style::Code) {
+                    continue;
+                }
+                if !tag.closing {
+                    if open.is_empty() {
+                        from = whole.end;
                     }
-                    None if !tag.closing && html::inline_style(&tag.name) == Some(Style::Code) => {
-                        code = Some((tag.name, whole.end));
+                    open.push(tag.name);
+                } else if let Some(ix) = open.iter().rposition(|name| *name == tag.name) {
+                    open.remove(ix);
+                    if open.is_empty() {
+                        kept[from..whole.start].fill(true);
                     }
-                    _ => {}
                 }
             }
             _ => {}
         }
     }
     // An unclosed `<code>` runs to its block's end.
-    if let Some((_, from)) = code {
+    if !open.is_empty() {
         kept[from..span(container).end].fill(true);
     }
 }
@@ -241,7 +246,7 @@ fn written_tex(value: &str, pair: &Pair, swapped: &Swapped, at: &Position) -> St
     tex.replace(char::from(swapped.stand_in), "$")
 }
 
-/// Restores a text's dollars; drops a parting space at its ends.
+/// Restores a text's dollars; drops parting spaces.
 fn trim(node: &mut mdast::Node, swapped: &Swapped) {
     let mdast::Node::Text(text) = node else {
         return;

src/documents/markdown/tex/tests.rs

@@ -83,6 +83,9 @@ fn code_and_tags_stay_literal() {
     untouched(r"a <code>\(x\)</code> b");
     untouched(r"a <kbd>\(x\)</kbd> b");
     untouched(r"a <code>\(x\) b");
+    untouched(r"a <code><code>\(x\)</code> \(y\)</code> b");
+    untouched(r"a <kbd><code>\(x\)</code> \(y\)</kbd> b");
+    assert_eq!(tex(r"<code>a</code> \(x\)"), ["x"], "after code, prose");
     untouched(r"`\(x\)`");
     untouched(r"\(a `b` c\)");
     assert_eq!(tex(r"<b>\(x\)</b>"), ["x"], "other tags hold prose");

src/documents/tree/mod.rs

@@ -323,7 +323,7 @@ impl<'a> Reader<'a> {
         if let [mdast::Node::InlineMath(math)] = children
             && ["$$", "\\["]
                 .iter()
-                .any(|open| self.source[span(node)].starts_with(open))
+                .any(|open| self.source[span(&children[0])].starts_with(open))
         {
             return out.push(Node::Math(math.value.trim().to_string()));
         }

src/documents/tree/tests.rs

@@ -421,6 +421,12 @@ fn the_first_shortcode_decides_its_text_node() {
 fn latex_delimiters_read_as_math() {
     assert_eq!(parse(r"\[c = 1\]"), [Node::Math("c = 1".into())]);
     assert_eq!(parse("\\[\nc = 1\n\\]"), [Node::Math("c = 1".into())]);
+    for indent in [" ", "  ", "   "] {
+        let source = format!(r"{indent}\[c = 1\]");
+        assert_eq!(parse(&source), [Node::Math("c = 1".into())], "{source:?}");
+        let source = format!("{indent}$$c = 1$$");
+        assert_eq!(parse(&source), [Node::Math("c = 1".into())], "{source:?}");
+    }
     let Node::Paragraph(inline) = &parse(r"so \(c\) holds")[0] else {
         panic!("inline math stays in its paragraph")
     };

src/typography/math.rs

@@ -193,7 +193,7 @@ fn framed(svg: &str, width: f32, height: f32) -> Result<(String, Size<Pixels>),
     Ok((wrapped(svg, [left, top, w, h])?, size(px(w), px(h))))
 }
 
-/// `svg` drawn in a px root viewing `[left, top, w, h]`.
+/// `svg` in a px root viewing `[left, top, w, h]`.
 fn wrapped(svg: &str, [left, top, w, h]: [f32; 4]) -> Result<String, MathError> {
     let open = svg
         .find('>')