Improved SimulatedSqlException creation consistency.

Author: RyanLamansky

SqlServerSimulator/Parser/ParserContext.cs

@@ -49,7 +49,7 @@ internal sealed class ParserContext(SimulatedDbCommand command)
     public object? GetVariableValue(string name) =>
         variables.TryGetValue(name, out var value)
         ? value.TypeValue.Value
-        : throw new SimulatedSqlException($"Must declare the scalar variable \"@{name}\".");
+        : throw SimulatedSqlException.MustDeclareScalarVariable(name);
 
     /// <summary>
     /// Advances <see cref="Token"/> to the next token, if one exists.

SqlServerSimulator/Parser/Tokenizer.cs

@@ -88,7 +88,7 @@ private static Token ParseAtOrDoubleAtPrefixedString(string command, ref int ind
     {
         var start = index;
         if (++index == command.Length)
-            throw new SimulatedSqlException("Must declare the scalar variable \"@\".");
+            throw SimulatedSqlException.MustDeclareScalarVariable(string.Empty);
 
         bool doubleAt;
         if (command[index] == '@')

SqlServerSimulator/Parser/Tokens/Numeric.cs

@@ -26,6 +26,6 @@ public Numeric(string command, int index, int length) : base(command, index, len
             return;
         }
 
-        throw new SimulatedSqlException($"Simulated command tokenizer couldn't parse {number} as a number.");
+        throw new NotSupportedException($"Simulated command tokenizer couldn't parse {number} as a number.");
     }
 }

SqlServerSimulator/SimulatedSqlException.cs

@@ -13,18 +13,13 @@ namespace SqlServerSimulator;
 /// </summary>
 internal sealed class SimulatedSqlException : DbException
 {
-    internal SimulatedSqlException(string? message)
-        : this(message, [])
-    {
-    }
-
     private SimulatedSqlException(string message, int number, byte @class, byte state)
         : this(message, new SimulatedSqlError(message, number, @class, state))
     {
     }
 
-    private SimulatedSqlException(string? message, params ReadOnlySpan<SimulatedSqlError> errors)
-        : base(message ?? "Simulated exception with no message.")
+    private SimulatedSqlException(string message, params ReadOnlySpan<SimulatedSqlError> errors)
+        : base(message)
     {
         base.HResult = unchecked((int)0x80131904);
         base.Source = "Core Microsoft SqlClient Data Provider";
@@ -106,6 +101,8 @@ internal static SimulatedSqlException ColumnReferenceNotAllowed(IEnumerable<stri
 
     internal static SimulatedSqlException InvalidObjectName(StringToken name) => new($"Invalid object name {name}.", 208, 16, 1);
 
+    internal static SimulatedSqlException MustDeclareScalarVariable(string name) => new($"Must declare the scalar variable \"@{name}\".", 137, 15, 2);
+
     internal static SimulatedSqlException SyntaxErrorNearKeyword(ReservedKeyword token) => new($"Incorrect syntax near the keyword '{token}'.", 156, 15, 1);
 
     internal static SimulatedSqlException SyntaxErrorNear(Token? token) => new($"Incorrect syntax near '{token}'.", 102, 15, 1);

SqlServerSimulator/Simulation.cs

@@ -90,11 +90,8 @@ internal IEnumerable<SimulatedStatementOutcome> CreateResultSetsForCommand(Simul
                                             do
                                             {
                                                 suppressAdvanceToken = false;
-                                                if (context.GetNextRequired() is not Name columnName)
-                                                    throw new SimulatedSqlException("Simulated table creation requires named columns.");
-
-                                                if (context.GetNextRequired() is not Name type)
-                                                    throw new SimulatedSqlException("Simulated table creation requires columns to have a type.");
+                                                var columnName = context.GetNextRequired<Name>();
+                                                var type = context.GetNextRequired<Name>();
 
                                                 var nullable = true;