Fix handling of documents containing only whitespace.

org_mode_samples/document/only_line_breaks.org

@@ -0,0 +1,4 @@
+
+
+
+

src/parser/document.rs

@@ -3,6 +3,7 @@ use std::path::Path;
 use nom::combinator::all_consuming;
 use nom::combinator::opt;
 use nom::multi::many0;
+use nom::InputTake;
 
 use super::headline::heading;
 use super::in_buffer_settings::apply_in_buffer_settings;
@@ -195,9 +196,9 @@ fn _document<'b, 'g, 'r, 's>(
             zeroth_section,
             children,
             contents: if contents.len() > 0 {
-                Some(Into::<&str>::into(contents))
+                Into::<&str>::into(contents)
             } else {
-                None
+                Into::<&str>::into(remaining.take(0))
             },
         },
     ))

src/types/document.rs

@@ -17,7 +17,7 @@ pub struct Document<'s> {
     pub path: Option<PathBuf>,
     pub zeroth_section: Option<Section<'s>>,
     pub children: Vec<Heading<'s>>,
-    pub contents: Option<&'s str>,
+    pub contents: &'s str,
 }
 
 #[derive(Debug)]
@@ -64,7 +64,7 @@ impl<'s> StandardProperties<'s> for Document<'s> {
     }
 
     fn get_contents<'b>(&'b self) -> Option<&'s str> {
-        self.contents
+        Some(self.contents)
     }
 
     fn get_post_blank(&self) -> PostBlank {