[SchemaValidator] Add error for switch field not found to ConditionRefValidator as well

Author: slotthhy

SchemaValidator/Validation/Validators/ConditionRefValidator.cs

@@ -1,4 +1,6 @@
-using EXDCommon;
+using System.Collections.Generic;
+using System.Linq;
+using EXDCommon;
 using EXDCommon.FileAccess;
 using EXDCommon.SchemaModel.EXDSchema;
 using EXDCommon.Sheets;
@@ -59,7 +61,16 @@ public override ValidationResults Validate(ExcelHeaderFile exh, Sheet sheet)
 		{
 			var offset = field.Definition.Offset;
 			var switchOn = field.Field.Condition.Switch;
-			var switchField = fields.First(f => f.Field.Name == switchOn);
+			var switchFields = fields.Where(f => f.Field.Name == switchOn).ToList();
+			
+			if (!switchFields.Any())
+			{
+				var msg = $"Column {field.Field.Name}@0x{offset:X} type {field.Definition.Type} has switch {switchOn} but no field by that name was found.";
+				results.Results.Add(ValidationResult.Failed(sheet.Name, ValidatorName(), msg));
+				continue;
+			}
+
+			var switchField = switchFields[0];
 			// var definedSwitchColumnValues = field.Field.Condition.Cases.Keys.ToHashSet();
 
 			// store the column values for each switch value