Add: [Script] GetExtraLastError and GetExtraLastErrorString

Allow scripts to get the extra error message of their last command.

Allow DoCommand and a few others to set extra error messages upon returning result.

Add regression tests.

regression/regression/main.nut

@@ -1828,6 +1828,17 @@ function Regression::Vehicle()
 	print("    GetLastErrorString():  " + AIError.GetLastErrorString());
 	print("    SendVehicleToDepot():  " + AIVehicle.SendVehicleToDepot(13));
 	print("    GetLastErrorString():  " + AIError.GetLastErrorString());
+	print("    BuildVehicle():        " + AIVehicle.BuildVehicle(33417, 116));
+	print("    AppendOrder():         " + AIOrder.AppendOrder(20, 33421, AIOrder.OF_NONE));
+	print("    GetLastError():        " + AIError.GetLastError());
+	print("    GetLastErrorString():  " + AIError.GetLastErrorString());
+	print("    GetExtraLastError():   " + AIError.GetExtraLastError());
+	print("    GetExtraLastErrorString(): " + AIError.GetExtraLastErrorString());
+	print("    SellVehicle():         " + AIVehicle.SellVehicle(20));
+	print("    GetLastError():        " + AIError.GetLastError());
+	print("    GetLastErrorString():  " + AIError.GetLastErrorString());
+	print("    GetExtraLastError():   " + AIError.GetExtraLastError());
+	print("    GetExtraLastErrorString(): " + AIError.GetExtraLastErrorString());
 
 	local list = AIVehicleList();
 	local in_depot = AIVehicleList(AIVehicle.IsInDepot);

regression/regression/result.txt

@@ -9546,6 +9546,17 @@ ERROR: IsEnd() is invalid as Begin() is never called
     GetLastErrorString():  ERR_VEHICLE_NOT_IN_DEPOT
     SendVehicleToDepot():  false
     GetLastErrorString():  ERR_UNKNOWN
+    BuildVehicle():        20
+    AppendOrder():         false
+    GetLastError():        1
+    GetLastErrorString():  ERR_UNKNOWN
+    GetExtraLastError():   1
+    GetExtraLastErrorString(): ERR_UNKNOWN
+    SellVehicle():         true
+    GetLastError():        0
+    GetLastErrorString():  ERR_NONE
+    GetExtraLastError():   0
+    GetExtraLastErrorString(): ERR_NONE
 
 --VehicleList--
   Count():             5
@@ -9588,7 +9599,7 @@ ERROR: IsEnd() is invalid as Begin() is never called
     13 => 5490
     12 => 5489
   CurrentSpeed ListDump:
-    12 => 27
+    12 => 31
     17 => 0
     16 => 0
     14 => 0
@@ -9763,9 +9774,9 @@ ERROR: IsEnd() is invalid as Begin() is never called
 --Valuate() with excessive CPU usage--
 Your script made an error: excessive CPU usage in valuator function
 
-*FUNCTION [unknown()] regression/main.nut line [2065]
+*FUNCTION [unknown()] regression/main.nut line [2076]
 *FUNCTION [Valuate()] NATIVE line [-1]
-*FUNCTION [Start()] regression/main.nut line [2066]
+*FUNCTION [Start()] regression/main.nut line [2077]
 
 [id] 0
 [this] TABLE
@@ -9774,7 +9785,7 @@ Your script made an error: excessive CPU usage in valuator function
 [this] INSTANCE
 Your script made an error: excessive CPU usage in valuator function
 
-*FUNCTION [Start()] regression/main.nut line [2066]
+*FUNCTION [Start()] regression/main.nut line [2077]
 
 [Infinite] CLOSURE
 [list] INSTANCE

src/script/api/ai_changelog.hpp

@@ -21,6 +21,8 @@
  * \li AIEventVehicleCrashed::GetVictims
  * \li AIEventCompanyRenamed
  * \li AIEventPresidentRenamed
+ * \li AIError::GetExtraLastError
+ * \li AIError::GetExtraLastErrorString
  *
  * \b 14.0
  *

src/script/api/game_changelog.hpp

@@ -21,6 +21,8 @@
  * \li GSEventVehicleCrashed::GetVictims
  * \li GSEventCompanyRenamed
  * \li GSEventPresidentRenamed
+ * \li GSError::GetExtraLastError
+ * \li GSError::GetExtraLastErrorString
  *
  * \b 14.0
  *

src/script/api/script_error.cpp

@@ -23,11 +23,21 @@ ScriptError::ScriptErrorMapString ScriptError::error_map_string = ScriptError::S
 	return ScriptObject::GetLastError();
 }
 
+/* static */ ScriptErrorType ScriptError::GetExtraLastError()
+{
+	return ScriptObject::GetExtraLastError();
+}
+
 /* static */ std::optional<std::string> ScriptError::GetLastErrorString()
 {
 	return (*error_map_string.find(ScriptError::GetLastError())).second;
 }
 
+/* static */ std::optional<std::string> ScriptError::GetExtraLastErrorString()
+{
+	return (*error_map_string.find(ScriptError::GetExtraLastError())).second;
+}
+
 /* static */ ScriptErrorType ScriptError::StringToError(StringID internal_string_id)
 {
 	StringIndexInTab index = GetStringIndex(internal_string_id);

src/script/api/script_error.hpp

@@ -21,6 +21,7 @@
 #define EnforcePrecondition(returnval, condition)               \
 	if (!(condition)) {                                           \
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_FAILED);   \
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);             \
 		return returnval;                                           \
 	}
 
@@ -33,6 +34,7 @@
 #define EnforcePreconditionCustomError(returnval, condition, error_code)   \
 	if (!(condition)) {                                                      \
 		ScriptObject::SetLastError(error_code);                                    \
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);             \
 		return returnval;                                                      \
 	}
 
@@ -44,6 +46,7 @@
 #define EnforcePreconditionEncodedText(returnval, string)   \
 	if (string.empty()) { \
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_FAILED); \
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);             \
 		return returnval; \
 	}
 
@@ -60,6 +63,7 @@
 #define EnforceCompanyModeValid_Void() \
 	if (!ScriptCompanyMode::IsValid()) { \
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_INVALID_COMPANY); \
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);             \
 		return; \
 	}
 
@@ -83,6 +87,7 @@
 #define EnforceDeityOrCompanyModeValid_Void() \
 	if (!(ScriptCompanyMode::IsDeity() || ScriptCompanyMode::IsValid())) { \
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_INVALID_COMPANY); \
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);             \
 		return; \
 	}
 
@@ -190,12 +195,24 @@ public:
 	 */
 	static ScriptErrorType GetLastError();
 
+	/**
+	 * Get the extra last error.
+	 * @return An ErrorMessages enum value.
+	 */
+	static ScriptErrorType GetExtraLastError();
+
 	/**
 	 * Get the last error in string format (for human readability).
 	 * @return An ErrorMessage enum item, as string.
 	 */
 	static std::optional<std::string> GetLastErrorString();
 
+	/**
+	 * Get the extra last error in string format (for human readability).
+	 * @return An ErrorMessage enum item, as string.
+	 */
+	static std::optional<std::string> GetExtraLastErrorString();
+
 	/**
 	 * Get the error based on the OpenTTD StringID.
 	 * @api -all

src/script/api/script_object.cpp

@@ -150,11 +150,21 @@ ScriptObject::ActiveInstance::~ActiveInstance()
 	GetStorage()->last_error = last_error;
 }
 
+/* static */ void ScriptObject::SetExtraLastError(ScriptErrorType extra_last_error)
+{
+	GetStorage()->extra_last_error = extra_last_error;
+}
+
 /* static */ ScriptErrorType ScriptObject::GetLastError()
 {
 	return GetStorage()->last_error;
 }
 
+/* static */ ScriptErrorType ScriptObject::GetExtraLastError()
+{
+	return GetStorage()->extra_last_error;
+}
+
 /* static */ void ScriptObject::SetLastCost(Money last_cost)
 {
 	GetStorage()->last_cost = last_cost;
@@ -286,6 +296,7 @@ std::tuple<bool, bool, bool, bool> ScriptObject::DoCommandPrep()
 
 	if (!ScriptCompanyMode::IsDeity() && !ScriptCompanyMode::IsValid()) {
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_INVALID_COMPANY);
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);
 		return { true, estimate_only, asynchronous, networking };
 	}
 
@@ -300,11 +311,13 @@ bool ScriptObject::DoCommandProcessResult(const CommandCost &res, Script_Suspend
 	/* We failed; set the error and bail out */
 	if (res.Failed()) {
 		SetLastError(ScriptError::StringToError(res.GetErrorMessage()));
+		SetExtraLastError(ScriptError::StringToError(res.GetExtraErrorMessage()));
 		return false;
 	}
 
 	/* No error, then clear it. */
 	SetLastError(ScriptError::ERR_NONE);
+	SetExtraLastError(ScriptError::ERR_NONE);
 
 	/* Estimates, update the cost for the estimate and be done */
 	if (estimate_only) {

src/script/api/script_object.hpp

@@ -174,11 +174,21 @@ protected:
 	 */
 	static void SetLastError(ScriptErrorType last_error);
 
+	/**
+	 * Set the DoCommand extra last error.
+	 */
+	static void SetExtraLastError(ScriptErrorType extra_last_error);
+
 	/**
 	 * Get the DoCommand last error.
 	 */
 	static ScriptErrorType GetLastError();
 
+	/**
+	 * Get the DoCommand extra last error.
+	 */
+	static ScriptErrorType GetExtraLastError();
+
 	/**
 	 * Set the road type.
 	 */

src/script/api/script_priorityqueue.cpp

@@ -52,6 +52,7 @@ SQInteger ScriptPriorityQueue::Pop(HSQUIRRELVM vm)
 {
 	if (this->IsEmpty()) {
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_FAILED);
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);
 		sq_pushnull(vm);
 		return 1;
 	}
@@ -70,6 +71,7 @@ SQInteger ScriptPriorityQueue::Peek(HSQUIRRELVM vm)
 {
 	if (this->IsEmpty()) {
 		ScriptObject::SetLastError(ScriptError::ERR_PRECONDITION_FAILED);
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);
 		sq_pushnull(vm);
 		return 1;
 	}

src/script/api/script_town.cpp

@@ -305,6 +305,7 @@
 	uint32_t townnameparts;
 	if (!GenerateTownName(ScriptObject::GetRandomizer(), &townnameparts)) {
 		ScriptObject::SetLastError(ScriptError::ERR_NAME_IS_NOT_UNIQUE);
+		ScriptObject::SetExtraLastError(ScriptError::ERR_UNKNOWN);
 		return false;
 	}
 

src/script/script_instance.cpp

@@ -759,6 +759,7 @@ bool ScriptInstance::DoCommandCallback(const CommandCost &result, const CommandD
 
 	if (result.Failed()) {
 		ScriptObject::SetLastError(ScriptError::StringToError(result.GetErrorMessage()));
+		ScriptObject::SetExtraLastError(ScriptError::StringToError(result.GetExtraErrorMessage()));
 	} else {
 		ScriptObject::IncreaseDoCommandCosts(result.GetCost());
 		ScriptObject::SetLastCost(result.GetCost());

src/script/script_storage.hpp

@@ -51,6 +51,7 @@ private:
 	CommandCost costs;               ///< The costs the script is tracking.
 	Money last_cost;                 ///< The last cost of the command.
 	ScriptErrorType last_error{}; ///< The last error of the command.
+	ScriptErrorType extra_last_error{}; ///< The extra last error of the command.
 	bool last_command_res;           ///< The last result of the command.
 
 	CommandDataBuffer last_data;     ///< The last data passed to a command.