Tracerestrict: Add release slot on reserve slot op subtype

src/lang/extra/english.txt

@@ -952,6 +952,7 @@ STR_TRACE_RESTRICT_SLOT_ACQUIRE_WAIT                            :Acquire or wait
 STR_TRACE_RESTRICT_SLOT_TRY_ACQUIRE                             :Try to acquire
 STR_TRACE_RESTRICT_SLOT_RELEASE_FRONT                           :Release (front)
 STR_TRACE_RESTRICT_SLOT_RELEASE_BACK                            :Release (back)
+STR_TRACE_RESTRICT_SLOT_RELEASE_ON_RESERVE                      :Release (on reserve)
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_ACQUIRE_WAIT                :PBS end: Acquire or wait
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_TRY_ACQUIRE                 :PBS end: Try to acquire
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_RELEASE                     :PBS end: Release
@@ -959,6 +960,7 @@ STR_TRACE_RESTRICT_SLOT_ACQUIRE_WAIT_ITEM                       :Acquire slot: {
 STR_TRACE_RESTRICT_SLOT_TRY_ACQUIRE_ITEM                        :Try to acquire slot: {STRING1}{BLACK}{STRING}, or continue anyway
 STR_TRACE_RESTRICT_SLOT_RELEASE_FRONT_ITEM                      :Release slot: {STRING1}{BLACK}{STRING} (front of train)
 STR_TRACE_RESTRICT_SLOT_RELEASE_BACK_ITEM                       :Release slot: {STRING1}{BLACK}{STRING} (back of train)
+STR_TRACE_RESTRICT_SLOT_RELEASE_ON_RESERVE_ITEM                 :Release slot: {STRING1}{BLACK}{STRING} (on PBS reserve)
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_ACQUIRE_WAIT_ITEM           :PBS reservation ending here: Acquire slot: {STRING1}{BLACK}{STRING}, or wait at start
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_TRY_ACQUIRE_ITEM            :PBS reservation ending here: Acquire slot: {STRING1}{BLACK}{STRING}, or continue anyway
 STR_TRACE_RESTRICT_SLOT_PBS_RES_END_RELEASE_ITEM                :PBS reservation ending here: Release slot: {STRING1}{BLACK}{STRING}

src/tracerestrict.cpp

@@ -744,6 +744,14 @@ void TraceRestrictProgram::Execute(const Train* v, const TraceRestrictProgramInp
 								}
 								break;
 
+							case TRSCOF_RELEASE_ON_RESERVE:
+								if (input.permitted_slot_operations & TRPISP_ACQUIRE) {
+									slot->Vacate(v->index);
+								} else if (input.permitted_slot_operations & TRPISP_ACQUIRE_TEMP_STATE) {
+									slot->VacateUsingTemporaryState(v->index, input.slot_temporary_state);
+								}
+								break;
+
 							case TRSCOF_RELEASE_BACK:
 								if (input.permitted_slot_operations & TRPISP_RELEASE_BACK) slot->Vacate(v->index);
 								break;
@@ -1357,6 +1365,10 @@ CommandCost TraceRestrictProgram::Validate(const std::vector<TraceRestrictItem>
 							actions_used_flags |= TRPAUF_SLOT_ACQUIRE;
 							break;
 
+						case TRSCOF_RELEASE_ON_RESERVE:
+							actions_used_flags |= TRPAUF_SLOT_ACQUIRE;
+							break;
+
 						case TRSCOF_RELEASE_BACK:
 							actions_used_flags |= TRPAUF_SLOT_RELEASE_BACK;
 							break;

src/tracerestrict.h

@@ -387,6 +387,7 @@ enum TraceRestrictSlotSubtypeField {
 	TRSCOF_PBS_RES_END_ACQ_WAIT   = 4,       ///< PBS reservations ending at this signal: acquire a slot, or wait
 	TRSCOF_PBS_RES_END_ACQ_TRY    = 5,       ///< PBS reservations ending at this signal: acquire a slot, or carry on otherwise
 	TRSCOF_PBS_RES_END_RELEASE    = 6,       ///< PBS reservations ending at this signal: release a slot
+	TRSCOF_RELEASE_ON_RESERVE     = 7,       ///< release a slot (on reserve)
 	/* space up to 31 */
 };
 
@@ -459,7 +460,7 @@ enum TraceRestrictProgramActionsUsedFlags {
 	TRPAUF_RESERVE_THROUGH        = 1 << 1,  ///< Reserve through action is present
 	TRPAUF_LONG_RESERVE           = 1 << 2,  ///< Long reserve action is present
 	TRPAUF_WAIT_AT_PBS            = 1 << 3,  ///< Wait at PBS signal action is present
-	TRPAUF_SLOT_ACQUIRE           = 1 << 4,  ///< Slot acquire action is present
+	TRPAUF_SLOT_ACQUIRE           = 1 << 4,  ///< Slot acquire and/or release (on reserve) actions are present
 	TRPAUF_SLOT_RELEASE_BACK      = 1 << 5,  ///< Slot release (back) action is present
 	TRPAUF_SLOT_RELEASE_FRONT     = 1 << 6,  ///< Slot release (front) action is present
 	TRPAUF_PBS_RES_END_WAIT       = 1 << 7,  ///< PBS reservations ending at this signal wait action is present
@@ -482,7 +483,7 @@ DECLARE_ENUM_AS_BIT_SET(TraceRestrictProgramActionsUsedFlags)
  * Enumeration for TraceRestrictProgramInput::permitted_slot_operations
  */
 enum TraceRestrictProgramInputSlotPermissions : uint8_t {
-	TRPISP_ACQUIRE                = 1 << 0,  ///< Slot acquire is permitted
+	TRPISP_ACQUIRE                = 1 << 0,  ///< Slot acquire and release (on reserve) are permitted
 	TRPISP_RELEASE_BACK           = 1 << 1,  ///< Slot release (back) is permitted
 	TRPISP_RELEASE_FRONT          = 1 << 2,  ///< Slot release (front) is permitted
 	TRPISP_PBS_RES_END_ACQUIRE    = 1 << 3,  ///< Slot acquire/release (PBS reservations ending at this signal) is permitted

src/tracerestrict_gui.cpp

@@ -815,6 +815,7 @@ static const StringID _slot_op_subtypes_str[] = {
 	STR_TRACE_RESTRICT_SLOT_TRY_ACQUIRE,
 	STR_TRACE_RESTRICT_SLOT_RELEASE_FRONT,
 	STR_TRACE_RESTRICT_SLOT_RELEASE_BACK,
+	STR_TRACE_RESTRICT_SLOT_RELEASE_ON_RESERVE,
 	STR_TRACE_RESTRICT_SLOT_PBS_RES_END_ACQUIRE_WAIT,
 	STR_TRACE_RESTRICT_SLOT_PBS_RES_END_TRY_ACQUIRE,
 	STR_TRACE_RESTRICT_SLOT_PBS_RES_END_RELEASE,
@@ -825,6 +826,7 @@ static const uint _slot_op_subtypes_val[] = {
 	TRSCOF_ACQUIRE_TRY,
 	TRSCOF_RELEASE_FRONT,
 	TRSCOF_RELEASE_BACK,
+	TRSCOF_RELEASE_ON_RESERVE,
 	TRSCOF_PBS_RES_END_ACQ_WAIT,
 	TRSCOF_PBS_RES_END_ACQ_TRY,
 	TRSCOF_PBS_RES_END_RELEASE,
@@ -1603,6 +1605,10 @@ static void DrawInstructionString(const TraceRestrictProgram *prog, TraceRestric
 						instruction_string = STR_TRACE_RESTRICT_SLOT_RELEASE_FRONT_ITEM;
 						break;
 
+					case TRSCOF_RELEASE_ON_RESERVE:
+						instruction_string = STR_TRACE_RESTRICT_SLOT_RELEASE_ON_RESERVE_ITEM;
+						break;
+
 					case TRSCOF_PBS_RES_END_ACQ_WAIT:
 						instruction_string = STR_TRACE_RESTRICT_SLOT_PBS_RES_END_ACQUIRE_WAIT_ITEM;
 						break;