Support drawers with only whitespace.

src/parser/drawer.rs

@@ -3,6 +3,7 @@ use nom::bytes::complete::tag;
 use nom::bytes::complete::take_while;
 use nom::character::complete::line_ending;
 use nom::character::complete::space0;
+use nom::combinator::consumed;
 use nom::combinator::eof;
 use nom::combinator::recognize;
 use nom::multi::many_till;
@@ -17,6 +18,7 @@ use crate::parser::exiting::ExitClass;
 use crate::parser::parser_context::ContextElement;
 use crate::parser::parser_context::ExitMatcherNode;
 use crate::parser::parser_with_context::parser_with_context;
+use crate::parser::util::blank_line;
 use crate::parser::util::exit_matcher_parser;
 use crate::parser::util::get_consumed;
 use crate::parser::util::immediate_in_section;
@@ -24,6 +26,8 @@ use crate::parser::util::maybe_consume_trailing_whitespace_if_not_exiting;
 use crate::parser::util::start_of_line;
 use crate::parser::util::WORD_CONSTITUENT_CHARACTERS;
 use crate::parser::Drawer;
+use crate::parser::Element;
+use crate::parser::Paragraph;
 
 #[tracing::instrument(ret, level = "debug")]
 pub fn drawer<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Drawer<'s>> {
@@ -51,8 +55,17 @@ pub fn drawer<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str,
 
     let element_matcher = parser_with_context!(element)(&parser_context);
     let exit_matcher = parser_with_context!(exit_matcher_parser)(&parser_context);
-    let (remaining, (children, _exit_contents)) =
-        many_till(element_matcher, exit_matcher)(remaining)?;
+    let (remaining, children) = match consumed(many_till(blank_line, exit_matcher))(remaining) {
+        Ok((remaining, (whitespace, (_children, _exit_contents)))) => (
+            remaining,
+            vec![Element::Paragraph(Paragraph::of_text(whitespace))],
+        ),
+        Err(_) => {
+            let (remaining, (children, _exit_contents)) =
+                many_till(element_matcher, exit_matcher)(remaining)?;
+            (remaining, children)
+        }
+    };
     let (remaining, _end) = drawer_end(&parser_context, remaining)?;
 
     let (remaining, _trailing_ws) =

toy_language.txt

@@ -1,8 +1,5 @@
-[fn:1] A footnote.
-
-[fn:2] A multi-
-
-line footnote.
+foo
+:drawername:
 
 
-not in the footnote.
+:end: