Add support for parsing description lists.

org_mode_samples/greater_element/plain_list/description_list.org

@@ -3,3 +3,5 @@
   dog
 - lorem
   :: ipsum
+-
+  lorem :: ipsum

src/parser/plain_list.rs

@@ -1,12 +1,15 @@
 use nom::branch::alt;
 use nom::bytes::complete::tag;
+use nom::character::complete::anychar;
 use nom::character::complete::digit1;
 use nom::character::complete::line_ending;
+use nom::character::complete::multispace1;
 use nom::character::complete::one_of;
 use nom::character::complete::space0;
 use nom::character::complete::space1;
 use nom::combinator::eof;
 use nom::combinator::opt;
+use nom::combinator::peek;
 use nom::combinator::recognize;
 use nom::combinator::verify;
 use nom::multi::many1;
@@ -138,7 +141,6 @@ pub fn plain_list_item<'r, 's>(
         Into::<&str>::into(bull) != "*" || indent_level > 0
     })(remaining)?;
 
-    // TODO: This isn't taking into account items that immediately line break and then have contents
     let maybe_contentless_item: Res<OrgSource<'_>, OrgSource<'_>> = eof(remaining);
     match maybe_contentless_item {
         Ok((rem, _ws)) => {
@@ -156,6 +158,7 @@ pub fn plain_list_item<'r, 's>(
         Err(_) => {}
     };
 
+    let (remaining, _maybe_tag) = opt(tuple((space1, item_tag, tag(" ::"))))(remaining)?;
     let (remaining, _ws) = alt((space1, line_ending))(remaining)?;
     let exit_matcher = plain_list_item_end(indent_level);
     let parser_context = context
@@ -262,6 +265,18 @@ fn _line_indented_lte<'r, 's>(
     Ok(matched)
 }
 
+#[cfg_attr(feature = "tracing", tracing::instrument(ret, level = "debug"))]
+fn item_tag<'s>(input: OrgSource<'s>) -> Res<OrgSource<'s>, OrgSource<'s>> {
+    recognize(many_till(
+        anychar,
+        peek(alt((
+            line_ending,
+            tag(" :: "),
+            recognize(tuple((tag(" ::"), alt((line_ending, eof))))),
+        ))),
+    ))(input)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;