primo commit

tests/test_dispatcher.py

@@ -0,0 +1,47 @@
+import ctypes
+
+from pybusmonitor1553.core.dispatcher import MessageDispatcher
+from pybusmonitor1553.lib1553.headers import (
+    UDP1553Header,
+    UDP1553MessageHeader,
+    CommandWordUnion,
+)
+from pybusmonitor1553.lib1553.constants import Subaddress
+
+
+def test_registry_contains_a1():
+    disp = MessageDispatcher()
+    key = (Subaddress.RX_SETTINGS, False)
+    assert key in disp._registry
+    cls = disp._registry[key]
+    assert cls.__name__ == "MsgA1"
+
+
+def test_parse_valid_a1_packet():
+    disp = MessageDispatcher()
+
+    # Build command word for A1 (Subaddress = RX_SETTINGS, transmit=False)
+    cw = CommandWordUnion(rt_addr=0, sub_addr=int(Subaddress.RX_SETTINGS), word_count=0, transmit=False)
+    msg_hdr = UDP1553MessageHeader(command_word_union=cw)
+    udp_hdr = UDP1553Header()
+
+    # Convert ctypes structs to raw bytes
+    header_bytes = ctypes.string_at(ctypes.addressof(udp_hdr), ctypes.sizeof(udp_hdr))
+    msg_hdr_bytes = ctypes.string_at(ctypes.addressof(msg_hdr), ctypes.sizeof(msg_hdr))
+
+    # Minimal data payload (64 bytes = 32 words) - all zeros is fine for parsing
+    data_bytes = b"\x00" * 64
+
+    raw = header_bytes + msg_hdr_bytes + data_bytes
+
+    h, msg = disp.parse_packet(raw)
+
+    assert h is not None
+    assert msg is not None
+    assert msg.__class__.__name__ == "MsgA1"
+
+
+def test_parse_too_short():
+    disp = MessageDispatcher()
+    h, msg = disp.parse_packet(b"\x00\x01")
+    assert h is None and msg is None