style: fix clippy warnings

Author: plusvic

lib/src/compiler/ir/dfs.rs

@@ -62,6 +62,7 @@ impl<'a> DepthFirstSearch<'a> {
     /// (i.e., the siblings of the node that was just left) from being visited.
     /// The next event will then be the [`Event::Leave`] for the parent of the
     /// node that was exited.
+    #[allow(dead_code)] // TODO: remove when this is used.
     pub fn prune(&mut self) {
         // Remove all Event::Enter from the stack until an Event::Leave.
         while let Some(Event::Enter(_)) = self.stack.last() {

lib/src/compiler/report.rs

@@ -350,7 +350,7 @@ impl ReportBuilder {
         let cache_entry = code_cache.get(&source_id).unwrap();
         let src = cache_entry.code.as_str();
 
-        src[source_ref.span.range()].to_string()
+        src[source_ref.span().range()].to_string()
     }
 
     /// Creates a new error or warning report.