env: handle the error properly

instead of:
env: unknown error: Os { code: 13, kind: PermissionDenied, message: "Permission denied" }

src/uu/env/src/env.rs

@@ -539,16 +539,19 @@ impl EnvAppData {
                 }
                 return Err(exit.code().unwrap().into());
             }
-            Err(ref err)
-                if (err.kind() == io::ErrorKind::NotFound)
-                    || (err.kind() == io::ErrorKind::InvalidInput) =>
-            {
-                return Err(self.make_error_no_such_file_or_dir(prog.deref()));
-            }
-            Err(e) => {
-                uucore::show_error!("unknown error: {:?}", e);
-                return Err(126.into());
-            }
+            Err(ref err) => match err.kind() {
+                io::ErrorKind::NotFound | io::ErrorKind::InvalidInput => {
+                    return Err(self.make_error_no_such_file_or_dir(prog.deref()));
+                }
+                io::ErrorKind::PermissionDenied => {
+                    uucore::show_error!("{}: Permission denied", prog.quote());
+                    return Err(126.into());
+                }
+                _ => {
+                    uucore::show_error!("unknown error: {:?}", err);
+                    return Err(126.into());
+                }
+            },
             Ok(_) => (),
         }
         Ok(())

tests/by-util/test_env.rs

@@ -80,6 +80,15 @@ fn test_env_version() {
         .stdout_contains(util_name!());
 }
 
+#[test]
+fn test_env_permissions() {
+    new_ucmd!()
+        .arg(".")
+        .fails()
+        .code_is(126)
+        .stderr_is("env: '.': Permission denied\n");
+}
+
 #[test]
 fn test_echo() {
     #[cfg(target_os = "windows")]