From 28b5cf1d340fab25db26755bb9bb3e58163f4ad3 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sun, 12 Apr 2020 16:02:26 -0400
Subject: [PATCH] Fix handling of surrounding whitespace

---
 src/parser/parser.rs | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/parser/parser.rs b/src/parser/parser.rs
index 37e6569..41d13bd 100644
--- a/src/parser/parser.rs
+++ b/src/parser/parser.rs
@@ -4,12 +4,15 @@ use nom::bytes::complete::is_a;
 use nom::bytes::complete::is_not;
 use nom::bytes::complete::tag;
 use nom::bytes::complete::take_until;
+use nom::bytes::complete::take_until_parser_matches;
+use nom::character::complete::line_ending;
+use nom::character::complete::multispace0;
 use nom::character::complete::one_of;
 use nom::character::complete::space1;
+use nom::combinator::all_consuming;
 use nom::combinator::map;
 use nom::combinator::opt;
 use nom::combinator::recognize;
-use nom::combinator::rest;
 use nom::combinator::value;
 use nom::combinator::verify;
 use nom::multi::many0;
@@ -471,7 +474,13 @@ fn filter(i: &str) -> IResult<&str, Filter> {
 
 /// Any text that is not a Dust element
 fn span(i: &str) -> IResult<&str, Span> {
-    let (remaining, body) = verify(alt((take_until("{"), rest)), |s: &str| s.len() > 0)(i)?;
+    let (remaining, body) = verify(
+        alt((
+            take_until("{"),
+            take_until_parser_matches(all_consuming(eof_whitespace)),
+        )),
+        |s: &str| s.len() > 0,
+    )(i)?;
     Ok((remaining, Span { contents: body }))
 }
 
@@ -489,7 +498,8 @@ fn body(i: &str) -> IResult<&str, Body> {
 }
 
 pub fn template(i: &str) -> IResult<&str, Template> {
-    let (remaining, contents) = body(i)?;
+    // DustJS ignores all preceding whitespace (tabs, newlines, spaces) but only ignores trailing newlines
+    let (remaining, contents) = delimited(multispace0, body, eof_whitespace)(i)?;
     Ok((remaining, Template { contents: contents }))
 }
 
@@ -501,6 +511,10 @@ fn quoted_string(i: &str) -> IResult<&str, String> {
     )(i)
 }
 
+fn eof_whitespace(i: &str) -> IResult<&str, Vec<&str>> {
+    many0(line_ending)(i)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;