Compare plain list item pre blank.

src/compare/diff.rs

@@ -53,6 +53,7 @@ use crate::types::PlainLink;
 use crate::types::PlainList;
 use crate::types::PlainListItem;
 use crate::types::PlainListItemCounter;
+use crate::types::PlainListItemPreBlank;
 use crate::types::PlainListType;
 use crate::types::PlainText;
 use crate::types::Planning;
@@ -887,7 +888,19 @@ fn compare_plain_list_item<'s>(
         }
     };
 
-    // TODO: Compare :pre-blank
+    // Compare pre-blank
+    // :pre-blank appears to count the line breaks between "::" and the contents in a descriptive list. Oddly enough it does not count the spaces so I'm not quite sure what the value is.
+    let pre_blank = get_property_unquoted_atom(emacs, ":pre-blank")?;
+    let pre_blank: Option<PlainListItemPreBlank> = pre_blank
+        .map(|val| val.parse())
+        .map_or(Ok(None), |r| r.map(Some))?;
+    if pre_blank.unwrap_or(0) != rust.pre_blank {
+        this_status = DiffStatus::Bad;
+        message = Some(format!(
+            "Pre-blank mismatch (emacs != rust) {:?} != {:?}",
+            pre_blank, rust.pre_blank
+        ));
+    }
 
     Ok(DiffResult {
         status: this_status,

src/parser/plain_list.rs

@@ -45,6 +45,7 @@ use crate::types::Object;
 use crate::types::PlainList;
 use crate::types::PlainListItem;
 use crate::types::PlainListItemCounter;
+use crate::types::PlainListItemPreBlank;
 use crate::types::PlainListType;
 
 #[cfg_attr(feature = "tracing", tracing::instrument(ret, level = "debug"))]
@@ -220,6 +221,7 @@ fn plain_list_item<'b, 'g, 'r, 's>(
                         tag: maybe_tag
                             .map(|(_ws, item_tag)| item_tag)
                             .unwrap_or(Vec::new()),
+                        pre_blank: 0,
                         children: Vec::new(),
                     },
                 ),
@@ -227,7 +229,11 @@ fn plain_list_item<'b, 'g, 'r, 's>(
         }
         Err(_) => {}
     };
-    let (remaining, _ws) = item_tag_post_gap(&parser_context, remaining)?;
+    let (remaining, pre_blank) = item_tag_post_gap(&parser_context, remaining)?;
+    let pre_blank = Into::<&str>::into(pre_blank)
+        .bytes()
+        .filter(|b| *b == b'\n')
+        .count();
 
     let (mut remaining, (mut children, _exit_contents)) = many_till(
         include_input(parser_with_context!(element(true))(&parser_context)),
@@ -266,6 +272,8 @@ fn plain_list_item<'b, 'g, 'r, 's>(
                 tag: maybe_tag
                     .map(|(_ws, item_tag)| item_tag)
                     .unwrap_or(Vec::new()),
+                pre_blank: PlainListItemPreBlank::try_from(pre_blank)
+                    .expect("pre-blank cannot be larger than 2."),
                 children: children.into_iter().map(|(_start, item)| item).collect(),
             },
         ),

src/types/greater_element.rs

@@ -29,10 +29,12 @@ pub struct PlainListItem<'s> {
     pub counter: Option<PlainListItemCounter>,
     pub checkbox: Option<(CheckboxType, &'s str)>,
     pub tag: Vec<Object<'s>>,
+    pub pre_blank: PlainListItemPreBlank,
     pub children: Vec<Element<'s>>,
 }
 
 pub type PlainListItemCounter = u16;
+pub type PlainListItemPreBlank = u8;
 
 #[derive(Debug)]
 pub enum CheckboxType {

src/types/mod.rs

@@ -25,6 +25,7 @@ pub use greater_element::NodeProperty;
 pub use greater_element::PlainList;
 pub use greater_element::PlainListItem;
 pub use greater_element::PlainListItemCounter;
+pub use greater_element::PlainListItemPreBlank;
 pub use greater_element::PlainListType;
 pub use greater_element::PropertyDrawer;
 pub use greater_element::Table;