🎉 Initial commit

tests/test_quality.py

@@ -0,0 +1,41 @@
+"""Quality decode tests (SPECIFICATION §7)."""
+
+import pytest
+
+from opcda_diagnozer.quality import QualityClass, decode_quality
+
+
+@pytest.mark.parametrize(
+    ("raw", "name", "quality_class"),
+    [
+        (0xC0, "GOOD", QualityClass.GOOD),
+        (0xD8, "GOOD_LOCAL_OVERRIDE", QualityClass.GOOD),
+        (0x44, "UNCERTAIN_LAST_USABLE", QualityClass.UNCERTAIN),
+        (0x40, "UNCERTAIN", QualityClass.UNCERTAIN),
+        (0x00, "BAD", QualityClass.BAD),
+        (0x04, "BAD_CONFIG_ERROR", QualityClass.BAD),
+        (0x08, "BAD_NOT_CONNECTED", QualityClass.BAD),
+        (0x0C, "BAD_DEVICE_FAILURE", QualityClass.BAD),
+        (0x10, "BAD_SENSOR_FAILURE", QualityClass.BAD),
+        (0x14, "BAD_LAST_KNOWN_VALUE", QualityClass.BAD),
+        (0x18, "BAD_COMM_FAILURE", QualityClass.BAD),
+        (0x1C, "BAD_OUT_OF_SERVICE", QualityClass.BAD),
+    ],
+)
+def test_spec_table_decodes(raw: int, name: str, quality_class: QualityClass) -> None:
+    info = decode_quality(raw)
+    assert info.name == name
+    assert info.quality_class is quality_class
+    assert info.raw_hex == f"0x{raw:02X}"
+
+
+def test_unknown_code_falls_back_to_class() -> None:
+    info = decode_quality(0x20)
+    assert info.quality_class is QualityClass.BAD
+    assert info.name.startswith("BAD_")
+
+
+def test_class_bits_come_from_low_byte() -> None:
+    # 16-bit quality word: the high byte must not affect the class (§7)
+    assert decode_quality(0x0118).quality_class is QualityClass.BAD
+    assert decode_quality(0xFFC0).quality_class is QualityClass.GOOD