From f820e27b17e346ca83f9b16493e4a7c5ede0c611 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Fri, 29 Sep 2023 13:03:01 -0400
Subject: [PATCH] Compare plain list type in diff.rs.

---
 src/compare/diff.rs      | 23 +++++++++++++++++++----
 src/compare/util.rs      | 12 ++++++++++++
 src/parser/plain_list.rs |  2 +-
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/src/compare/diff.rs b/src/compare/diff.rs
index da654d6..0bfd6ba 100644
--- a/src/compare/diff.rs
+++ b/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_unquoted_atom;
 use crate::types::AngleLink;
 use crate::types::BabelCall;
 use crate::types::Bold;
@@ -50,6 +51,7 @@ use crate::types::Paragraph;
 use crate::types::PlainLink;
 use crate::types::PlainList;
 use crate::types::PlainListItem;
+use crate::types::PlainListType;
 use crate::types::PlainText;
 use crate::types::Planning;
 use crate::types::PriorityCookie;
@@ -748,11 +750,24 @@ fn compare_plain_list<'s>(
 ) -> Result<DiffEntry<'s>, Box<dyn std::error::Error>> {
     let children = emacs.as_list()?;
     let mut child_status = Vec::new();
-    let this_status = DiffStatus::Good;
-    let message = None;
-    // TODO: Compare :type
-    //
+    let mut this_status = DiffStatus::Good;
+    let mut message = None;
+
     // :type is an unquoted atom of either descriptive, ordered, or unordered
+    let list_type = get_property_unquoted_atom(emacs, ":type")?;
+    match (list_type, &rust.list_type) {
+        (None, _) => panic!("Emacs returned a list with no type."),
+        (Some("unordered"), PlainListType::Unordered) => {}
+        (Some("ordered"), PlainListType::Ordered) => {}
+        (Some("descriptive"), PlainListType::Descriptive) => {}
+        _ => {
+            this_status = DiffStatus::Bad;
+            message = Some(format!(
+                "List type mismatch (emacs != rust) {:?} != {:?}",
+                list_type, rust.list_type
+            ));
+        }
+    }
 
     for (emacs_child, rust_child) in children.iter().skip(2).zip(rust.children.iter()) {
         child_status.push(compare_plain_list_item(source, emacs_child, rust_child)?);
diff --git a/src/compare/util.rs b/src/compare/util.rs
index 21580a9..f52ef47 100644
--- a/src/compare/util.rs
+++ b/src/compare/util.rs
@@ -190,3 +190,15 @@ pub(crate) fn get_property<'s, 'x>(
     };
     Ok(Some(*prop))
 }
+
+/// Get a named property containing an unquoted atom from the emacs token.
+///
+/// Returns None if key is not found.
+pub(crate) fn get_property_unquoted_atom<'s, 'x>(
+    emacs: &'s Token<'s>,
+    key: &'x str,
+) -> Result<Option<&'s str>, Box<dyn std::error::Error>> {
+    Ok(get_property(emacs, key)?
+        .map(Token::as_atom)
+        .map_or(Ok(None), |r| r.map(Some))?)
+}
diff --git a/src/parser/plain_list.rs b/src/parser/plain_list.rs
index b12451c..f2e4313 100644
--- a/src/parser/plain_list.rs
+++ b/src/parser/plain_list.rs
@@ -148,7 +148,7 @@ pub(crate) fn plain_list<'b, 'g, 'r, 's>(
         remaining,
         PlainList {
             source: source.into(),
-            list_type: PlainListType::Ordered,
+            list_type: first_item_list_type.expect("Plain lists require at least one element."),
             children: children.into_iter().map(|(_start, item)| item).collect(),
         },
     ))