From 5b146d7c074de0305177f349f435e4593f2664b3 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Mon, 9 Oct 2023 22:37:53 -0400
Subject: [PATCH] compare_properties drawer.

---
 src/compare/diff.rs | 62 +++++++++++++++++++++++++++------------------
 1 file changed, 37 insertions(+), 25 deletions(-)

diff --git a/src/compare/diff.rs b/src/compare/diff.rs
index 859189a5..8bacae30 100644
--- a/src/compare/diff.rs
+++ b/src/compare/diff.rs
@@ -1530,35 +1530,47 @@ fn compare_drawer<'b, 's>(
     emacs: &'b Token<'s>,
     rust: &'b Drawer<'s>,
 ) -> Result<DiffEntry<'b, 's>, Box<dyn std::error::Error>> {
-    let children = emacs.as_list()?;
-    let mut child_status = Vec::new();
     let mut this_status = DiffStatus::Good;
+    let mut child_status = Vec::new();
     let mut message = None;
 
-    // TODO: Compare :caption
-    // Compare name
-    let name = get_property_quoted_string(emacs, ":name")?;
-    if name.as_ref().map(String::as_str) != rust.name {
-        this_status = DiffStatus::Bad;
-        message = Some(format!(
-            "Name mismatch (emacs != rust) {:?} != {:?}",
-            name, rust.name
-        ));
-    }
+    compare_children(
+        source,
+        emacs,
+        &rust.children,
+        &mut child_status,
+        &mut this_status,
+        &mut message,
+    )?;
 
-    // Compare drawer-name
-    let drawer_name =
-        get_property_quoted_string(emacs, ":drawer-name")?.ok_or("Drawers should have a name.")?;
-    if drawer_name != rust.drawer_name {
-        this_status = DiffStatus::Bad;
-        message = Some(format!(
-            "Drawer name mismatch (emacs != rust) {:?} != {:?}",
-            drawer_name, rust.drawer_name
-        ));
-    }
-
-    for (emacs_child, rust_child) in children.iter().skip(2).zip(rust.children.iter()) {
-        child_status.push(compare_ast_node(source, emacs_child, rust_child.into())?);
+    for diff in compare_properties!(
+        source,
+        emacs,
+        rust,
+        (
+            EmacsField::Optional(":name"),
+            |r| r.name,
+            compare_property_quoted_string
+        ),
+        (
+            EmacsField::Optional(":caption"),
+            compare_identity,
+            compare_noop
+        ),
+        (
+            EmacsField::Required(":drawer-name"),
+            |r| Some(r.drawer_name),
+            compare_property_quoted_string
+        )
+    ) {
+        match diff {
+            ComparePropertiesResult::NoChange => {}
+            ComparePropertiesResult::SelfChange(new_status, new_message) => {
+                this_status = new_status;
+                message = new_message
+            }
+            ComparePropertiesResult::DiffEntry(diff_entry) => child_status.push(diff_entry),
+        }
     }
 
     Ok(DiffResult {