A first stab at a final item whitespace cut-off exit matcher.

src/parser/plain_list.rs

@@ -3,6 +3,7 @@ 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;
@@ -17,6 +18,7 @@ use nom::multi::many0;
 use nom::multi::many1;
 use nom::multi::many_till;
 use nom::sequence::tuple;
+use nom::InputTake;
 
 use super::affiliated_keyword::parse_affiliated_keywords;
 use super::element_parser::element;
@@ -81,6 +83,28 @@ where
     return Err(nom::Err::Error(CustomError::Static("No element detected.")));
 }
 
+#[cfg_attr(
+    feature = "tracing",
+    tracing::instrument(ret, level = "debug", skip(context))
+)]
+pub(crate) fn detect_not_plain_list_item_indent<'b, 'g, 'r, 's>(
+    context: RefContext<'b, 'g, 'r, 's>,
+    input: OrgSource<'s>,
+) -> Res<OrgSource<'s>, (u16, OrgSource<'s>)> {
+    if let Ok((_remaining, (_, indent, _))) = tuple((
+        start_of_line,
+        parser_with_context!(indentation_level)(context),
+        not(tuple((
+            parser_with_context!(bullet)(context),
+            alt((space1, line_ending, eof)),
+        ))),
+    ))(input)
+    {
+        return Ok((input, indent));
+    }
+    return Err(nom::Err::Error(CustomError::Static("No element detected.")));
+}
+
 #[cfg_attr(
     feature = "tracing",
     tracing::instrument(ret, level = "debug", skip(context, affiliated_keywords))
@@ -204,15 +228,21 @@ fn plain_list_item<'b, 'g, 'r, 's>(
     };
 
     let exit_matcher = plain_list_item_end(indent_level);
+    let final_item_whitespace_cutoff = final_item_whitespace_cutoff(indent_level);
     let contexts = [
         ContextElement::ConsumeTrailingWhitespace(true),
         ContextElement::ExitMatcherNode(ExitMatcherNode {
             class: ExitClass::Beta,
             exit_matcher: &exit_matcher,
         }),
+        ContextElement::ExitMatcherNode(ExitMatcherNode {
+            class: ExitClass::Beta,
+            exit_matcher: &final_item_whitespace_cutoff,
+        }),
     ];
     let parser_context = context.with_additional_node(&contexts[0]);
     let parser_context = parser_context.with_additional_node(&contexts[1]);
+    let parser_context = parser_context.with_additional_node(&contexts[2]);
 
     let maybe_contentless_item: Res<OrgSource<'_>, ()> =
         detect_contentless_item_contents(&parser_context, remaining);
@@ -356,6 +386,52 @@ fn counter_set_value<'s>(input: OrgSource<'s>) -> Res<OrgSource<'s>, PlainListIt
     ))(input)
 }
 
+const fn final_item_whitespace_cutoff(indent_level: IndentationLevel) -> impl ContextMatcher {
+    move |context, input: OrgSource<'_>| {
+        impl_final_item_whitespace_cutoff(context, input, indent_level)
+    }
+}
+
+#[cfg_attr(
+    feature = "tracing",
+    tracing::instrument(ret, level = "debug", skip(context))
+)]
+fn impl_final_item_whitespace_cutoff<'b, 'g, 'r, 's>(
+    context: RefContext<'b, 'g, 'r, 's>,
+    input: OrgSource<'s>,
+    indent_level: IndentationLevel,
+) -> Res<OrgSource<'s>, OrgSource<'s>> {
+    start_of_line(input)?;
+    // element!(plain_list_end, context, input);
+
+    if let Ok((_remaining, _)) = verify(
+        tuple((
+            opt(blank_line),
+            bind_context!(indentation_level, context),
+            not(multispace1),
+        )),
+        |(_, (depth, _stars), _not_whitespace)| *depth < indent_level,
+    )(input)
+    {
+        return Ok((input, input.take(0)));
+    }
+
+    if let Ok((_remaining, _)) = tuple((
+        opt(blank_line),
+        verify(
+            bind_context!(detect_not_plain_list_item_indent, context),
+            |(depth, _)| *depth == indent_level,
+        ),
+    ))(input)
+    {
+        return Ok((input, input.take(0)));
+    }
+
+    Err(nom::Err::Error(CustomError::Static(
+        "No whitespace cut-off.",
+    )))
+}
+
 #[cfg_attr(
     feature = "tracing",
     tracing::instrument(ret, level = "debug", skip(_context))