1 files changed, 41 insertions, 0 deletions

diff --git a/src/ast.rs b/src/ast.rs
index f627178..bc3547d 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -89,6 +89,12 @@ impl<'a> Document {
     {
         let mut ast: Pandoc = serde_json::from_str(json)?;
         let meta = Metadata::new(basedir, &ast)?;
+        let mut linter = LintingVisitor::default();
+        linter.walk_pandoc(&mut ast);
+        if !linter.issues.is_empty() {
+            // Currently we can't really return more than one error so return one
+            return Err(linter.issues.remove(0));
+        }
         let files = DataFiles::new(&mut ast);
         Ok(Document::new(markdowns, ast, meta, files))
     }
@@ -1077,6 +1083,41 @@ impl MutVisitor for BlockClassVisitor {
     }
 }
 
+#[derive(Default)]
+struct LintingVisitor {
+    issues: Vec<SubplotError>,
+}
+
+impl MutVisitor for LintingVisitor {
+    fn visit_vec_block(&mut self, vec_block: &mut Vec<Block>) {
+        for block in vec_block {
+            match block {
+                Block::CodeBlock(attr, _) => {
+                    if is_class(attr, "file") {
+                        let newlines: Vec<_> = find_attr_kv(&attr, "add-newline").collect();
+                        match newlines.len() {
+                            0 => {}
+                            1 => match newlines[0].to_ascii_lowercase().as_ref() {
+                                "auto" | "yes" | "no" => {}
+                                _ => self.issues.push(SubplotError::UnrecognisedAddNewline(
+                                    get_filename(&attr),
+                                    newlines[0].to_owned(),
+                                )),
+                            },
+                            _ => self.issues.push(SubplotError::RepeatedAddNewlineAttribute(
+                                get_filename(&attr),
+                            )),
+                        }
+                    }
+                }
+                _ => {
+                    self.visit_block(block);
+                }
+            }
+        }
+    }
+}
+
 /// Get the base directory given the name of the markdown file.
 ///
 /// All relative filename, such as bindings files, are resolved