From 41927764fc6f79240295f4a75f0c6cf3654af59a Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sat, 22 Feb 2025 18:39:41 -0500
Subject: [PATCH] Continue highlights across code block lines.

---
 TODO.org                      |  4 ++--
 src/intermediate/src_block.rs | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/TODO.org b/TODO.org
index 46cb300..cb2226c 100644
--- a/TODO.org
+++ b/TODO.org
@@ -1,4 +1,4 @@
-* Things to do [3/14]
+* Things to do [4/14]
 ** DONE If the paragraph only contains an image, text-align center
 ** DONE Syntax highlighting for code blocks
 ** TODO Render gnuplot
@@ -14,4 +14,4 @@
 ** TODO Add highlighting for languages [0/2]
 *** TODO bash
 *** TODO gnuplot
-** TODO Bug: carry over highlight starts when breaking lines
+** DONE Bug: carry over highlight starts when breaking lines
diff --git a/src/intermediate/src_block.rs b/src/intermediate/src_block.rs
index 7b357ab..4588256 100644
--- a/src/intermediate/src_block.rs
+++ b/src/intermediate/src_block.rs
@@ -169,6 +169,7 @@ where
 
     let mut highlighted_text: Vec<ISrcLine> = Vec::with_capacity(lines.len());
     let mut current_line = ISrcLine::new();
+    let mut highlight_stack: Vec<&str> = Vec::new();
     for event in highlights {
         match event.unwrap() {
             HighlightEvent::Source { start, end } => {
@@ -178,8 +179,22 @@ where
                     current_line
                         .children
                         .push(ISrcSegment::RawText(first_line.to_owned()));
+                    current_line.children.extend(
+                        highlight_stack
+                            .iter()
+                            .map(|_name| ISrcSegment::HighlightEnd),
+                    );
                     highlighted_text.push(current_line);
                     current_line = ISrcLine::new();
+                    current_line
+                        .children
+                        .extend(
+                            highlight_stack
+                                .iter()
+                                .map(|name| ISrcSegment::HighlightStart {
+                                    name: (*name).into(),
+                                }),
+                        );
                     span = &span[(line_break_index + 1)..];
                 }
                 if !span.is_empty() {
@@ -189,16 +204,20 @@ where
                 }
             }
             HighlightEvent::HighlightStart(s) => {
+                highlight_stack.push(highlight_names[s.0]);
                 current_line.children.push(ISrcSegment::HighlightStart {
                     name: highlight_names[s.0].into(),
                 });
             }
             HighlightEvent::HighlightEnd => {
+                highlight_stack.pop();
                 current_line.children.push(ISrcSegment::HighlightEnd);
             }
         }
     }
 
+    debug_assert!(highlight_stack.is_empty());
+
     Ok(highlighted_text)
 }