Compare footnote section.

src/compare/diff.rs

@@ -9,6 +9,7 @@ use super::sexp::unquote;
 use super::sexp::Token;
 use super::util::compare_standard_properties;
 use super::util::get_property;
+use super::util::get_property_boolean;
 use super::util::get_property_quoted_string;
 use super::util::get_property_unquoted_atom;
 use crate::types::AngleLink;
@@ -726,7 +727,17 @@ fn compare_heading<'s>(
         ));
     }
 
-    // TODO: Compare :pre-blank :footnote-section-p :scheduled :closed
+    // Compare footnote-section-p
+    let footnote_section = get_property_boolean(emacs, ":footnote-section-p")?;
+    if footnote_section != rust.is_footnote_section {
+        this_status = DiffStatus::Bad;
+        message = Some(format!(
+            "footnote section mismatch (emacs != rust) {:?} != {:?}",
+            footnote_section, rust.is_footnote_section
+        ));
+    }
+
+    // TODO: Compare :pre-blank :scheduled :closed
     //
     // :scheduled and :closed seem to only appear when the headline has a planning
 

src/compare/util.rs

@@ -217,3 +217,19 @@ pub(crate) fn get_property_quoted_string<'s, 'x>(
         .map(unquote)
         .map_or(Ok(None), |r| r.map(Some))?)
 }
+
+/// Get a named property containing a boolean value.
+///
+/// This uses the elisp convention of nil == false, non-nil == true.
+///
+/// Returns false if key is not found.
+pub(crate) fn get_property_boolean<'s, 'x>(
+    emacs: &'s Token<'s>,
+    key: &'x str,
+) -> Result<bool, Box<dyn std::error::Error>> {
+    Ok(get_property(emacs, key)?
+        .map(Token::as_atom)
+        .map_or(Ok(None), |r| r.map(Some))?
+        .unwrap_or("nil")
+        != "nil")
+}