Add test for TTY

tests/test_operator_env.py

@@ -42,6 +42,16 @@ class UpdateEnvFileTests(unittest.TestCase):
 
 
 class CollectUpdatesTests(unittest.TestCase):
+    def test_interactive_accepts_dev_tty_when_stdin_is_not_tty(self) -> None:
+        fake_tty = mock.mock_open()
+        with mock.patch.object(oe.sys.stdin, "isatty", return_value=False), mock.patch.object(
+            oe.sys.stderr,
+            "isatty",
+            return_value=True,
+        ), mock.patch("builtins.open", fake_tty):
+            self.assertTrue(oe.interactive())
+        fake_tty.assert_called_once_with("/dev/tty", "r", encoding="utf-8")
+
     def test_collects_password_github_and_pyarmor_when_missing(self) -> None:
         env_values = {
             oe.DEVPI_PASSWORD_KEY: "change-me",