Fix handling of whitespace.

src/compare/mod.rs

@@ -2,3 +2,4 @@ mod error;
 mod parse;
 mod sexp;
 pub use parse::emacs_parse_org_document;
+pub use sexp::sexp;

src/compare/sexp.rs

@@ -3,7 +3,10 @@ use nom::bytes::complete::tag;
 use nom::bytes::complete::take_till1;
 use nom::character::complete::multispace0;
 use nom::character::complete::multispace1;
+use nom::combinator::not;
+use nom::combinator::peek;
 use nom::multi::separated_list1;
+use nom::sequence::delimited;
 
 use super::error::Res;
 
@@ -29,13 +32,14 @@ fn token<'s>(input: &'s str) -> Res<&'s str, Token<'s>> {
 #[tracing::instrument(ret, level = "debug")]
 fn list<'s>(input: &'s str) -> Res<&'s str, Token<'s>> {
     let (remaining, opening_paren) = tag("(")(input)?;
-    let (remaining, children) = separated_list1(multispace1, token)(remaining)?;
+    let (remaining, children) = delimited(multispace0, separated_list1(multispace1, token), multispace0)(remaining)?;
     let (remaining, closing_paren) = tag(")")(remaining)?;
     Ok((remaining, Token::List(children)))
 }
 
 #[tracing::instrument(ret, level = "debug")]
 fn atom<'s>(input: &'s str) -> Res<&'s str, Token<'s>> {
+    not(peek(tag(")")))(input)?;
     unquoted_atom(input)
 }