Log the cluster logfile on error.

Author: nihohit

redis/tests/support/cluster.rs

@@ -206,6 +206,7 @@ impl RedisCluster {
 
                         match process.try_wait() {
                             Ok(Some(status)) => {
+                                
                                 let stdout = process.stdout.map_or(String::new(), |mut out|{
                                     let mut str = String::new();
                                     out.read_to_string(&mut str).unwrap();
@@ -219,7 +220,10 @@ impl RedisCluster {
                                 let err =
                                     format!("redis server creation failed with status {status:?}.\nstdout: `{stdout}`.\nstderr: `{stderr}`");
                                 if cur_attempts == max_attempts {
-                                    panic!("{err}");
+                                    let log_file_index = cmd.get_args().position(|os_str| os_str == "--logfile").unwrap() + 1;
+                                    let log_file_path = cmd.get_args().skip(log_file_index).next().unwrap();
+                                    let contents = std::fs::read_to_string(log_file_path).unwrap();
+                                    panic!("{err} - logfile: {contents}");
                                 }
                                 eprintln!("Retrying: {err}");
                                 cur_attempts += 1;