From 0095b1d0458b088319bb1678dddd8b56769160b1 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Wed, 23 Sep 2026 15:00:14 +0000
Subject: [PATCH] test(nmea): add unit tests for NMEASentenceHandler decode
 protocol method

---
 tests/test_nmea/test_protocols.py | 45 ++++++++++++++++++++++++++++++-
 1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/tests/test_nmea/test_protocols.py b/tests/test_nmea/test_protocols.py
index e2abac6..1ab6d65 100644
--- a/tests/test_nmea/test_protocols.py
+++ b/tests/test_nmea/test_protocols.py
@@ -2,6 +2,8 @@
 
 from typing import Any
 
+import pytest
+
 from nmea.protocols import NMEASentenceHandler
 
 
@@ -9,7 +11,9 @@ class ConformingNMEADecoder:
     """A dummy class that implements the NMEASentenceHandler protocol."""
 
     def decode(self, sentence: str) -> dict[str, Any]:
-        return {"talker": "GP", "sentence_id": "RMC"}
+        if not sentence.startswith("$") and not sentence.startswith("!"):
+            raise ValueError("Invalid NMEA sentence format")
+        return {"talker": sentence[1:3], "sentence_id": sentence[3:6], "raw": sentence}
 
     def checksum(self, sentence: str) -> str:
         return "00"
@@ -29,6 +33,13 @@ def checksum(self, sentence: str) -> str:
         return "00"
 
 
+def process_nmea_sentence(
+    handler: NMEASentenceHandler, sentence: str
+) -> dict[str, Any]:
+    """Helper function to test protocol-based decoding behavior."""
+    return handler.decode(sentence)
+
+
 def test_nmea_sentence_handler_conforming() -> None:
     """Test that a compliant class is recognized by the protocol."""
     decoder = ConformingNMEADecoder()
@@ -42,3 +53,35 @@ def test_nmea_sentence_handler_non_conforming() -> None:
 
     missing_decode = NonConformingNMEADecoderMissingDecode()
     assert not isinstance(missing_decode, NMEASentenceHandler)
+
+
+def test_nmea_sentence_handler_decode_execution() -> None:
+    """Test calling the decode method on a conforming NMEASentenceHandler instance."""
+    decoder: NMEASentenceHandler = ConformingNMEADecoder()
+    sentence = "$GPRMC,123519,A,4807.038,N,01131.000,E,022.4,084.4,230394,003.1,W*6A"
+
+    result = decoder.decode(sentence)
+
+    assert isinstance(result, dict)
+    assert result["talker"] == "GP"
+    assert result["sentence_id"] == "RMC"
+    assert result["raw"] == sentence
+
+
+def test_nmea_sentence_handler_decode_via_protocol_helper() -> None:
+    """Test calling decode via a function accepting NMEASentenceHandler protocol type."""
+    decoder = ConformingNMEADecoder()
+    sentence = "$GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,,*47"
+
+    result = process_nmea_sentence(decoder, sentence)
+
+    assert result == {"talker": "GP", "sentence_id": "GGA", "raw": sentence}
+
+
+def test_nmea_sentence_handler_decode_error_handling() -> None:
+    """Test that decode propagates exceptions for invalid inputs when implemented."""
+    decoder = ConformingNMEADecoder()
+    invalid_sentence = "INVALID_SENTENCE"
+
+    with pytest.raises(ValueError, match="Invalid NMEA sentence format"):
+        decoder.decode(invalid_sentence)