tests ~ reorganize tests

tests/by-util/test_users.rs

@@ -0,0 +1,30 @@
+use crate::common::util::*;
+use std::env;
+
+#[test]
+fn test_users_noarg() {
+    let (_, mut ucmd) = at_and_ucmd!();
+    let result = ucmd.run();
+    assert!(result.success);
+}
+#[test]
+fn test_users_check_name() {
+    let result = TestScenario::new(util_name!()).ucmd_keepenv().run();
+    assert!(result.success);
+
+    // Expectation: USER is often set
+    let key = "USER";
+
+    match env::var(key) {
+        Err(e) => println!("Key {} isn't set. Found {}", &key, e),
+        Ok(username) =>
+        // Check if "users" contains the name of the user
+        {
+            println!("username found {}", &username);
+            println!("result.stdout {}", &result.stdout);
+            if !&result.stdout.is_empty() {
+                assert!(result.stdout.contains(&username))
+            }
+        }
+    }
+}