refactor: delay use of pandoc_ast::Map to as late as possible

Use YamlMetadata instead. I find this to be clearer and that it
reduces the coupling with pandoc_ast a little. This should help us
when we implement document metadata in a separate YAML file instead of
embedding it in the Markdown.

Sponsored-by: author

1 files changed, 6 insertions, 8 deletions

diff --git a/src/ast.rs b/src/ast.rs
index 430e26c..4fba52e 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -25,21 +25,21 @@ lazy_static! {
 #[derive(Debug)]
 pub struct AbstractSyntaxTree {
     blocks: Vec<Block>,
-    meta: Map<String, MetaValue>,
+    meta: YamlMetadata,
 }
 
 impl AbstractSyntaxTree {
     // Create a new AST.
     //
     // Note that this is not public.
-    fn new(meta: Map<String, MetaValue>, blocks: Vec<Block>) -> Self {
+    fn new(meta: YamlMetadata, blocks: Vec<Block>) -> Self {
         Self { blocks, meta }
     }
 
     /// Return a Pandoc-compatible AST.
     pub fn to_pandoc(&self) -> Pandoc {
         Pandoc {
-            meta: self.meta.clone(),
+            meta: self.meta.to_map(),
             blocks: self.blocks.clone(),
             pandoc_api_version: vec![1, 20],
         }
@@ -54,18 +54,18 @@ impl std::str::FromStr for AbstractSyntaxTree {
         trace!("Parsing markdown");
         let ast = if let Some((yaml, markdown)) = get_yaml(&LEADING_YAML_PATTERN, markdown) {
             trace!("Found leading YAML: {:?}", yaml);
-            let meta = YamlMetadata::new(yaml)?.to_map();
+            let meta = YamlMetadata::new(yaml)?;
             let blocks = parse_blocks(markdown);
             AbstractSyntaxTree::new(meta, blocks)
         } else if let Some((yaml, _markdown)) = get_yaml(&TRAILING_YAML_PATTERN, markdown) {
             trace!("Found trailing YAML: {:?}", yaml);
-            let meta = YamlMetadata::new(yaml)?.to_map();
+            let meta = YamlMetadata::new(yaml)?;
             let blocks = parse_blocks(markdown);
             AbstractSyntaxTree::new(meta, blocks)
         } else {
             trace!("No YAML to be found");
             let blocks = parse_blocks(markdown);
-            AbstractSyntaxTree::new(Map::new(), blocks)
+            AbstractSyntaxTree::new(YamlMetadata::default(), blocks)
         };
         trace!("Parsing markdown: OK");
         Ok(ast)
@@ -404,7 +404,6 @@ mod test {
         let ast = AbstractSyntaxTree::from_str("").unwrap();
         let doc = ast.to_pandoc();
         assert!(doc.blocks.is_empty());
-        assert!(doc.meta.is_empty());
         assert!(!doc.pandoc_api_version.is_empty());
     }
 
@@ -419,7 +418,6 @@ mod test {
         )
         .unwrap();
         let doc = ast.to_pandoc();
-        assert!(doc.meta.is_empty());
         assert!(!doc.pandoc_api_version.is_empty());
 
         let attr = ("".to_string(), vec![], vec![]);