fix: handle empty content

core/src/unimarkup.rs

@@ -80,6 +80,13 @@ impl Html<'_> {
 ///
 /// Returns a [`CoreError`], if error occurs during compilation.
 pub fn compile(um_content: &str, mut config: Config) -> Result<UnimarkupDocument, CoreError> {
+    if um_content.is_empty() {
+        return Ok(UnimarkupDocument {
+            elements: vec![],
+            config,
+        });
+    }
+
     let mut connection = middleend::setup_ir_connection()?;
     middleend::setup_ir(&connection)?;
 

core/tests/unimarkup.rs

@@ -0,0 +1,17 @@
+#![allow(non_snake_case)]
+
+use clap::Parser;
+use unimarkup_core::config::Config;
+
+#[test]
+fn test__compile__empty_content() {
+    let cfg: Config = Config::parse_from(vec![
+        "unimarkup",
+        "--output-formats=html",
+        "tests/test_files/all_syntax.um",
+    ]);
+
+    let rendered_result = unimarkup_core::unimarkup::compile("", cfg);
+
+    assert!(rendered_result.unwrap().elements.is_empty());
+}