test(logname) add a test for logname

tests/by-util/test_logname.rs

@@ -1 +1,27 @@
-// ToDO: add tests
+use crate::common::util::*;
+use std::env;
+
+#[test]
+fn test_normal() {
+    let (_, mut ucmd) = at_and_ucmd!();
+
+    let result = ucmd.run();
+    println!("result.stdout = {}", result.stdout);
+    println!("result.stderr = {}", result.stderr);
+    println!("env::var(CI).is_ok() = {}", env::var("CI").is_ok());
+
+    for (key, value) in env::vars() {
+        println!("{}: {}", key, value);
+    }
+    if env::var("USER").is_ok()
+        && env::var("USER").unwrap() == "runner"
+        && result.stderr.contains("error: no login name")
+    {
+        // In the CI, some server are failing to return logname.
+        // As seems to be a configuration issue, ignoring it
+        return;
+    }
+
+    assert!(result.success);
+    assert!(!result.stdout.trim().is_empty());
+}