diff --git a/rust-code-analysis-cli/src/main.rs b/rust-code-analysis-cli/src/main.rs
index fed4e2456..de6b8b1c6 100644
--- a/rust-code-analysis-cli/src/main.rs
+++ b/rust-code-analysis-cli/src/main.rs
@@ -97,8 +97,11 @@ fn act_on_file(language: Option<LANG>, path: PathBuf, cfg: &Config) -> std::io::
         action::<Dump>(&language, source, &path, pr, cfg)
     } else if cfg.metrics {
         if let Some(output_format) = &cfg.output_format {
-            let space = get_function_spaces(&language, source, &path, pr).unwrap();
-            output_format.dump_formats(&space, &path, &cfg.output, cfg.pretty)
+            if let Some(space) = get_function_spaces(&language, source, &path, pr) {
+                output_format.dump_formats(&space, &path, &cfg.output, cfg.pretty)
+            } else {
+                Ok(())
+            }
         } else {
             let cfg = MetricsCfg { path };
             action::<Metrics>(&language, source, &cfg.path.clone(), pr, cfg)
diff --git a/src/spaces.rs b/src/spaces.rs
index 8875c49c8..ece102ac0 100644
--- a/src/spaces.rs
+++ b/src/spaces.rs
@@ -180,23 +180,26 @@ fn compute_halstead_and_mi<'a, T: ParserTrait>(state: &mut State<'a>) {
 }
 
 fn finalize<'a, T: ParserTrait>(state_stack: &mut Vec<State<'a>>, diff_level: usize) {
+    if state_stack.is_empty() {
+        return;
+    }
     for _ in 0..diff_level {
-        if state_stack.len() <= 1 {
+        if state_stack.len() == 1 {
             let mut last_state = state_stack.last_mut().unwrap();
             compute_halstead_and_mi::<T>(&mut last_state);
             break;
-        }
-
-        let mut state = state_stack.pop().unwrap();
-        compute_halstead_and_mi::<T>(&mut state);
+        } else {
+            let mut state = state_stack.pop().unwrap();
+            compute_halstead_and_mi::<T>(&mut state);
 
-        let mut last_state = state_stack.last_mut().unwrap();
-        last_state.halstead_maps.merge(&state.halstead_maps);
-        compute_halstead_and_mi::<T>(&mut last_state);
+            let mut last_state = state_stack.last_mut().unwrap();
+            last_state.halstead_maps.merge(&state.halstead_maps);
+            compute_halstead_and_mi::<T>(&mut last_state);
 
-        // Merge function spaces
-        last_state.space.metrics.merge(&state.space.metrics);
-        last_state.space.spaces.push(state.space);
+            // Merge function spaces
+            last_state.space.metrics.merge(&state.space.metrics);
+            last_state.space.spaces.push(state.space);
+        }
     }
 }