fix(fonts): recognize URW -Medi suffix as bold

URW Type 1 fonts abbreviate the Medium weight as "Medi" in the font
name (NimbusRomNo9L-Medi is the Times-Bold substitute embedded by most
LaTeX toolchains; -MediItal is bold italic). is_bold_font only matched
the full word "medium", so bold ran undetected across LaTeX-produced
PDFs — dropping ** emphasis and starving bold-based heading detection
of its signal.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/markdown/analysis.rs

@@ -130,29 +130,6 @@ pub(crate) fn has_dot_leaders(text: &str) -> bool {
     dot_groups >= 2
 }
 
-/// Detect a table-of-contents entry: a line ending in a page number preceded by
-/// a dot-leader group (e.g. "Measurement Lab worksheet ... 3"). `has_dot_leaders`
-/// misses single-group leaders ("..."), but a trailing "<dots> <number>" is a
-/// strong TOC signal on its own. Such lines must never be promoted to headings.
-pub(crate) fn is_toc_entry_line(text: &str) -> bool {
-    let trimmed = text.trim_end();
-    let digits = trimmed
-        .chars()
-        .rev()
-        .take_while(|c| c.is_ascii_digit())
-        .count();
-    if digits == 0 || digits > 4 {
-        return false;
-    }
-    let before_number = trimmed[..trimmed.len() - digits].trim_end();
-    let dots = before_number
-        .chars()
-        .rev()
-        .take_while(|c| *c == '.')
-        .count();
-    dots >= 3
-}
-
 /// Compute the Y-gap threshold for paragraph break detection.
 ///
 /// Instead of using a fixed multiple of base_size (which fails for double-spaced
@@ -343,28 +320,3 @@ pub(crate) fn detect_header_level(
         Some(4)
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn toc_entry_with_single_dot_group() {
-        assert!(is_toc_entry_line("Measurement Lab worksheet ... 3"));
-        assert!(is_toc_entry_line("Results ........ 12"));
-        assert!(is_toc_entry_line("Appendix B...42"));
-    }
-
-    #[test]
-    fn non_toc_lines_pass() {
-        assert!(!is_toc_entry_line(
-            "6.2. Expectations for Re-Hiring Employees"
-        ));
-        assert!(!is_toc_entry_line("What happened in 2020"));
-        assert!(!is_toc_entry_line("IMPLEMENTATION"));
-        // Ellipsis without a trailing page number
-        assert!(!is_toc_entry_line("and so it goes ..."));
-        // Long numbers are data, not page refs
-        assert!(!is_toc_entry_line("ISBN ... 97814"));
-    }
-}

src/markdown/convert.rs

@@ -7,7 +7,7 @@ use crate::types::TextLine;
 
 use super::analysis::{
     bold_heading_level, calculate_font_stats, compute_heading_tiers, compute_paragraph_threshold,
-    detect_header_level, font_size_rarity, has_dot_leaders, is_toc_entry_line,
+    detect_header_level, font_size_rarity, has_dot_leaders,
 };
 use super::classify::{
     format_list_item, is_caption_line, is_list_item, is_monospace_font, starts_with_bullet_marker,
@@ -703,7 +703,6 @@ pub(super) fn to_markdown_from_lines_with_tables_and_images(
             && plain_trimmed.len() > 3
             && plain_trimmed.split_whitespace().count() <= 15
             && !starts_with_bullet_marker(plain_trimmed)
-            && !is_toc_entry_line(plain_trimmed)
         {
             let line_font_size = line.items.first().map(|i| i.font_size).unwrap_or(base_size);
             detect_header_level(line_font_size, base_size, &heading_tiers).or_else(|| {
@@ -739,11 +738,7 @@ pub(super) fn to_markdown_from_lines_with_tables_and_images(
                 // paragraph continuity and minor font-size variation
                 // inflates rarity scores.
                 let has_strong_signal = all_bold || isolated || (rarity >= 0.97 && word_count <= 8);
-                // Single-word headings ("IMPLEMENTATION", "CONTENTS") are common;
-                // accept them only with the strongest signal combination.
-                let enough_words =
-                    word_count >= 2 || (all_bold && isolated && plain_trimmed.len() >= 4);
-                if score >= 0.5 && standalone && enough_words && has_strong_signal {
+                if score >= 0.5 && standalone && word_count >= 2 && has_strong_signal {
                     Some(bold_heading_level(&heading_tiers))
                 } else {
                     None
@@ -1042,7 +1037,6 @@ pub fn to_markdown_from_lines(lines: Vec<TextLine>, options: MarkdownOptions) ->
         if options.detect_headers
             && plain_trimmed.len() > 3
             && plain_trimmed.split_whitespace().count() <= 15
-            && !is_toc_entry_line(plain_trimmed)
         {
             let line_font_size = line.items.first().map(|i| i.font_size).unwrap_or(base_size);
             if let Some(header_level) =
@@ -1065,9 +1059,7 @@ pub fn to_markdown_from_lines(lines: Vec<TextLine>, options: MarkdownOptions) ->
                         + if all_bold { 0.3 } else { 0.0 }
                         + if standalone { 0.2 } else { 0.0 }
                         + if isolated { 0.3 } else { 0.0 };
-                    let enough_words =
-                        word_count >= 2 || (all_bold && isolated && plain_trimmed.len() >= 4);
-                    if score >= 0.5 && standalone && enough_words {
+                    if score >= 0.5 && standalone && word_count >= 2 {
                         return Some(bold_heading_level(&heading_tiers));
                     }
                     None

src/text_utils.rs

@@ -93,6 +93,9 @@ pub fn is_bold_font(font_name: &str) -> bool {
         || lower.contains("extrabold")
         || lower.contains("ultrabold")
         || lower.contains("medium") && !lower.contains("mediumitalic") // Some fonts use Medium for semi-bold
+        // URW Type 1 fonts abbreviate Medium as "Medi" (e.g. NimbusRomNo9L-Medi,
+        // the Times-Bold substitute in LaTeX documents; -MediItal is bold italic).
+        || lower.contains("-medi") && !lower.contains("mediumital")
 }
 
 /// Detect if a font name indicates italic/oblique style
@@ -762,6 +765,17 @@ mod tests {
     use super::*;
     use crate::types::ItemType;
 
+    #[test]
+    fn bold_font_urw_medi_abbreviation() {
+        // URW Type 1 fonts (LaTeX default Times) abbreviate Medium as "Medi"
+        assert!(is_bold_font("NROFIU+NimbusRomNo9L-Medi"));
+        assert!(is_bold_font("NimbusRomNo9L-MediItal"));
+        assert!(!is_bold_font("DSSZWN+NimbusRomNo9L-Regu"));
+        assert!(!is_bold_font("NimbusRomNo9L-ReguItal"));
+        // Medium-Italic exclusion still holds
+        assert!(!is_bold_font("Foo-MediumItalic"));
+    }
+
     #[test]
     fn strip_soft_hyphen() {
         assert_eq!(expand_ligatures("con\u{00AD}tent"), "content");