From 74ff028751f0130197ede03bdd2b53c6faa4981d Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Tue, 22 Sep 2026 04:14:00 +0000
Subject: [PATCH] test(nmea): add unit tests for print_response in znt.py

---
 src/nmea/znt.py             |  3 ++-
 tests/test_nmea/test_znt.py | 40 +++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/src/nmea/znt.py b/src/nmea/znt.py
index 3993117..6b38002 100755
--- a/src/nmea/znt.py
+++ b/src/nmea/znt.py
@@ -15,6 +15,7 @@
 except ImportError:
     ntplib = None
 
+import datetime
 import functools
 import operator
 import optparse
@@ -75,7 +76,7 @@ def print_response(response):
     )
     print("Poll : %d" % response.poll)
     print("Mode : %s (%d)" % (ntplib.mode_to_text(response.mode), response.mode))
-    print(f"Python time: {time.time():f}, {datetime.datetime.utcnow()!s}")
+    print(f"Python time: {time.time():f}, {datetime.datetime.now(datetime.UTC)!s}")
     print("Transmit timestamp : " + time.ctime(response.tx_time))
     print("Reference timestamp : " + time.ctime(response.ref_time))
     print("Original timestamp : " + time.ctime(response.orig_time))
diff --git a/tests/test_nmea/test_znt.py b/tests/test_nmea/test_znt.py
index 074796c..69d89a8 100644
--- a/tests/test_nmea/test_znt.py
+++ b/tests/test_nmea/test_znt.py
@@ -195,3 +195,43 @@ def test_znt_logger_update_no_write(mock_znt_class):
     # Force write
     logger.update(force=True)
     assert mock_znt_class.called
+
+
+def test_print_response(capsys):
+    response = MockNTPStats()
+    znt.print_response(response)
+
+    captured = capsys.readouterr()
+    stdout = captured.out
+
+    assert "Version number : 4" in stdout
+    assert "Offset : 0.000080" in stdout
+    assert "Stratum :" in stdout
+    assert "Precision : -20" in stdout
+    assert "Root delay : 0.117325" in stdout
+    assert "Root dispersion : 0.046249" in stdout
+    assert "Delay : 0.001000" in stdout
+    assert "Leap indicator :" in stdout
+    assert "Poll : 6" in stdout
+    assert "Mode :" in stdout
+    assert "Python time:" in stdout
+    assert "Transmit timestamp :" in stdout
+    assert "Reference timestamp :" in stdout
+    assert "Original timestamp :" in stdout
+    assert "Receive timestamp :" in stdout
+    assert "Destination timestamp :" in stdout
+    assert "Reference clock identifier :" in stdout
+
+
+def test_print_response_stratum_1(capsys):
+    response = MockNTPStats()
+    response.stratum = 1
+    response.ref_id = 1195725632  # 'GPS ' in 32-bit uint
+    znt.print_response(response)
+
+    captured = capsys.readouterr()
+    stdout = captured.out
+
+    assert "Stratum :" in stdout
+    assert "(1)" in stdout
+    assert "Reference clock identifier :" in stdout