fix(plc4go): unbreak plc4xGenerator on bacnetip DriverContext

Phase-1's DriverContext introduced the first non-pointer `model.*` enum
fields used directly as struct members. plc4xGenerator's
serializableFieldTemplate emits `if x != nil` for any SelectorExpr field,
which is valid for pointer/interface fields but invalid Go for value-typed
enums like MaxApduLengthAccepted / BACnetSegmentation / MaxSegmentsAccepted.
CI's regenerated DriverContext_plc4xgen.go therefore failed to compile,
breaking the mockery step.

Mark the three enum fields with `stringer:"true"` so the generator calls
their generated `.String()` instead of the SelectorExpr template. Mirrors
how knxnetip's KnxMedium and opcua's UserTokenType are tagged. The enum
values now appear by name in debug output instead of being hidden.

Also check in the generated Configuration_plc4xgen.go and
DriverContext_plc4xgen.go alongside MessageCodec_plc4xgen.go and
Subscriber_plc4xgen.go (cbus and opcua track theirs too).

Author: sruehl

plc4go/internal/bacnetip/Configuration_plc4xgen.go

@@ -34,15 +34,15 @@ type DriverContext struct {
 	// maxApduLengthAccepted is the Configuration.MaxApduLengthAccepted byte count
 	// translated to its BACnet enum value (used in IAm responses and confirmed
 	// requests). E.g. 1476 → MaxApduLengthAccepted_NUM_OCTETS_1476.
-	maxApduLengthAccepted model.MaxApduLengthAccepted
+	maxApduLengthAccepted model.MaxApduLengthAccepted `stringer:"true"`
 
 	// segmentation is Configuration.SegmentationSupported translated to its
 	// BACnet enum. Defaults to SEGMENTED_BOTH for unknown strings.
-	segmentation model.BACnetSegmentation
+	segmentation model.BACnetSegmentation `stringer:"true"`
 
 	// maxSegmentsAccepted is Configuration.MaxSegmentsAccepted translated to its
 	// BACnet enum value (e.g. 16 → NUM_SEGMENTS_16).
-	maxSegmentsAccepted model.MaxSegmentsAccepted
+	maxSegmentsAccepted model.MaxSegmentsAccepted `stringer:"true"`
 
 	awaitSetupComplete      bool
 	awaitDisconnectComplete bool

plc4go/internal/bacnetip/DriverContext.go

@@ -127,4 +127,3 @@ func (m *MessageCodec) Receive(ctx context.Context) (spi.Message, error) {
 	// TODO: maybe we return here a not enough error error
 	return nil, nil
 }
-

plc4go/internal/bacnetip/DriverContext_plc4xgen.go

@@ -64,12 +64,12 @@ func (f *fakeTransportInstance) WrittenBytes() []byte {
 	return append([]byte(nil), f.writeBuffer.Bytes()...)
 }
 
-func (f *fakeTransportInstance) Connect(_ context.Context) error           { f.connected = true; return nil }
+func (f *fakeTransportInstance) Connect(_ context.Context) error            { f.connected = true; return nil }
 func (f *fakeTransportInstance) ConnectWithContext(_ context.Context) error { return f.Connect(nil) }
-func (f *fakeTransportInstance) Close() error                              { f.connected = false; return nil }
-func (f *fakeTransportInstance) IsConnected() bool                         { return f.connected }
-func (f *fakeTransportInstance) String() string                            { return "fake" }
-func (f *fakeTransportInstance) Reset()                                    {}
+func (f *fakeTransportInstance) Close() error                               { f.connected = false; return nil }
+func (f *fakeTransportInstance) IsConnected() bool                          { return f.connected }
+func (f *fakeTransportInstance) String() string                             { return "fake" }
+func (f *fakeTransportInstance) Reset()                                     {}
 
 func (f *fakeTransportInstance) GetNumBytesAvailableInBuffer() (uint32, error) {
 	f.mu.Lock()

plc4go/internal/bacnetip/MessageCodec.go

@@ -35,12 +35,12 @@ import (
 // expected sequence number, returning a SegmentAck PDU the caller must transmit
 // after every received segment.
 type inboundReassembler struct {
-	invokeId     uint8
-	expectedSeq  uint8
-	buffer       []byte
-	windowSize   uint8 // actual window size we advertised in the original request
-	moreFollows  bool
-	complete     bool
+	invokeId    uint8
+	expectedSeq uint8
+	buffer      []byte
+	windowSize  uint8 // actual window size we advertised in the original request
+	moreFollows bool
+	complete    bool
 }
 
 // NewInboundReassembler creates a fresh reassembler tracking the given invoke
@@ -100,13 +100,13 @@ func (r *inboundReassembler) Bytes() []byte { return r.buffer }
 // SendNext returns the next segment to put on the wire, then waits for the
 // remote SegmentAck via AcknowledgeSegment before calling SendNext again.
 type outboundSegmenter struct {
-	invokeId     uint8
-	payload      []byte
-	maxSegment   uint16 // bytes per segment (peer's max APDU minus header overhead)
-	windowSize   uint8
-	nextSeq      uint8
-	cursor       int  // byte offset into payload
-	done         bool
+	invokeId   uint8
+	payload    []byte
+	maxSegment uint16 // bytes per segment (peer's max APDU minus header overhead)
+	windowSize uint8
+	nextSeq    uint8
+	cursor     int // byte offset into payload
+	done       bool
 }
 
 // NewOutboundSegmenter prepares a segmenter for the given serialized request

plc4go/internal/bacnetip/MessageCodec_test.go

@@ -97,10 +97,10 @@ func TestTagHandler_ParseInvalidString(t *testing.T) {
 	cases := []string{
 		"",
 		"garbage",
-		"ANALOG_INPUT,1",       // missing property
-		"ANALOG_INPUT/X",       // missing instance
-		"ANALOG_INPUT,abc/X",   // non-numeric instance
-		",1/X",                 // missing object type
+		"ANALOG_INPUT,1",     // missing property
+		"ANALOG_INPUT/X",     // missing instance
+		"ANALOG_INPUT,abc/X", // non-numeric instance
+		",1/X",               // missing object type
 	}
 	for _, c := range cases {
 		_, err := h.ParseTag(c)

plc4go/internal/bacnetip/Segmentation.go

@@ -41,7 +41,7 @@ import (
 //   - CharacterString→ PlcSTRING
 //   - OctetString    → PlcRawByteArray
 //   - Enumerated     → PlcUDINT (the raw numeric; the property identifier on
-//                      the request side determines the enum schema)
+//     the request side determines the enum schema)
 //   - BitString      → PlcRawByteArray (packed MSB-first)
 //   - Date           → PlcDATE       (year-1900 + month + day-of-month)
 //   - Time           → PlcTIME_OF_DAY