tree update!

crates/treehouse-format/src/ast.rs

@@ -7,11 +7,14 @@ use crate::{
 
 #[derive(Debug, Clone)]
 pub struct Roots {
+    pub attributes: Option<Attributes>,
     pub branches: Vec<Branch>,
 }
 
 impl Roots {
     pub fn parse(parser: &mut Parser) -> Result<Self, ParseError> {
+        let attributes = parser.top_level_attributes()?;
+
         let mut branches = vec![];
         while let Some((branch, indent_level)) = Branch::parse_with_indent_level(parser)? {
             if indent_level != 0 {
@@ -19,7 +22,10 @@ impl Roots {
             }
             branches.push(branch);
         }
-        Ok(Self { branches })
+        Ok(Self {
+            attributes,
+            branches,
+        })
     }
 }
 

crates/treehouse-format/src/pull.rs

@@ -151,6 +151,34 @@ impl<'a> Parser<'a> {
         Ok(())
     }
 
+    pub fn top_level_attributes(&mut self) -> Result<Option<Attributes>, ParseError> {
+        let start = self.position;
+        match self.current() {
+            Some('%') => {
+                let after_one_percent = self.position;
+                self.advance();
+                if self.current() == Some('%') {
+                    self.advance();
+                    let after_two_percent = self.position;
+                    self.eat_indented_lines_until(
+                        0,
+                        |c| c == '-' || c == '+' || c == '%',
+                        AllowCodeBlocks::No,
+                    )?;
+                    let end = self.position;
+                    Ok(Some(Attributes {
+                        percent: start..after_two_percent,
+                        data: after_two_percent..end,
+                    }))
+                } else {
+                    self.position = after_one_percent;
+                    Ok(None)
+                }
+            }
+            _ => Ok(None),
+        }
+    }
+
     pub fn next_branch(&mut self) -> Result<Option<BranchEvent>, ParseError> {
         if self.current().is_none() {
             return Ok(None);