1 files changed, 1 insertions, 0 deletions
diff --git a/src/bin/sp-docgen.rs b/src/bin/sp-docgen.rs
index c9e4879..fc53e47 100644
--- a/src/bin/sp-docgen.rs
+++ b/src/bin/sp-docgen.rs
@@ -52,6 +52,7 @@ fn main() -> subplot::Result<()> {
     // file from the AST.
     pandoc.add_filter(|json| {
         let mut doc = subplot::Document::from_json(&json).expect("error parsing JSON AST");
+        doc.has_title().expect("document has no title");
         doc.typeset();
         doc.ast().expect("error serializing into JSON AST")
     });