better code coverage

Author: 2bndy5

cpp-linter/src/run.rs

@@ -57,12 +57,12 @@ pub async fn run_main(args: Vec<String>) -> Result<()> {
     }
 
     if cli.source_options.repo_root != "." {
-        env::set_current_dir(Path::new(&cli.source_options.repo_root)).unwrap_or_else(|_| {
-            panic!(
-                "'{}' is inaccessible or does not exist",
+        env::set_current_dir(Path::new(&cli.source_options.repo_root)).map_err(|e| {
+            anyhow!(
+                "'{}' is inaccessible or does not exist: {e:?}",
                 cli.source_options.repo_root
             )
-        });
+        })?;
     }
 
     let rest_api_client = GithubApiClient::new()?;
@@ -240,4 +240,16 @@ mod test {
         .await;
         assert!(result.is_ok());
     }
+
+    #[tokio::test]
+    async fn bad_repo_root() {
+        env::remove_var("GITHUB_OUTPUT"); // avoid writing to GH_OUT in parallel-running tests
+        let result = run_main(vec![
+            "cpp-linter".to_string(),
+            "-r".to_string(),
+            "some-non-existent-dir".to_string(),
+        ])
+        .await;
+        assert!(result.is_err());
+    }
 }