Code clean-up

- Dialect encapsulates Keywords
- AbstractDataBaseSchema and SybaseAnywhereColumnMetaData return case insensitive hash set (in fact, they can return an array/IEnumerable<string> instead of ISet<string>)
- SchemaMetadataUpdater does not do unnecessary hash sets recast
- SchemaMetadataUpdater just sets IsQuoted for table and column names, so it does not do unnecessary string operations

Author: hazzik

src/NHibernate/Dialect/Dialect.cs

@@ -44,7 +44,6 @@ public abstract class Dialect
 		private readonly TypeNames _hibernateTypeNames = new TypeNames();
 		private readonly IDictionary<string, string> _properties = new Dictionary<string, string>();
 		private readonly IDictionary<string, ISQLFunction> _sqlFunctions;
-		private readonly HashSet<string> _sqlKeywords;
 
 		private static readonly IDictionary<string, ISQLFunction> StandardAggregateFunctions = CollectionHelper.CreateCaseInsensitiveHashtable<ISQLFunction>();
 
@@ -82,7 +81,7 @@ protected Dialect()
 
 			_sqlFunctions = CollectionHelper.CreateCaseInsensitiveHashtable(StandardAggregateFunctions);
 
-			_sqlKeywords = new HashSet<string>(AnsiSqlKeywords.Sql2003, StringComparer.OrdinalIgnoreCase);
+			Keywords = new HashSet<string>(AnsiSqlKeywords.Sql2003, StringComparer.OrdinalIgnoreCase);
 
 			// standard sql92 functions (can be overridden by subclasses)
 			RegisterFunction("substring", new AnsiSubstringFunction());
@@ -2088,10 +2087,7 @@ public virtual IDictionary<string, ISQLFunction> Functions
 			get { return _sqlFunctions; }
 		}
 
-		public HashSet<string> Keywords
-		{
-			get { return _sqlKeywords; }
-		}
+		public HashSet<string> Keywords { get; }
 
 		/// <summary> 
 		/// Get the command used to select a GUID from the underlying database.
@@ -2248,11 +2244,21 @@ protected void RegisterKeyword(string word)
 			Keywords.Add(word);
 		}
 
-		protected void RegisterKeywords(params string[] keywords)
+		protected internal void RegisterKeywords(params string[] keywords)
 		{
 			Keywords.UnionWith(keywords);
 		}
 
+		protected internal void RegisterKeywords(IEnumerable<string> keywords)
+		{
+			Keywords.UnionWith(keywords);
+		}
+
+		public bool IsKeyword(string str)
+		{
+			return Keywords.Contains(str);
+		}
+
 		protected void RegisterFunction(string name, ISQLFunction function)
 		{
 			_sqlFunctions[name] = function;
@@ -2288,4 +2294,4 @@ public virtual ISQLExceptionConverter BuildSQLExceptionConverter()
 			return new SQLStateConverter(ViolatedConstraintNameExtracter);
 		}
 	}
-}
+}

src/NHibernate/Dialect/Schema/AbstractDataBaseSchema.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Data;
 using System.Data.Common;
@@ -95,7 +96,7 @@ public virtual DataTable GetForeignKeys(string catalog, string schema, string ta
 
 		public virtual ISet<string> GetReservedWords()
 		{
-			var result = new HashSet<string>();
+			var result = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
 			DataTable dtReservedWords = connection.GetSchema(DbMetaDataCollectionNames.ReservedWords);
 			foreach (DataRow row in dtReservedWords.Rows)
 			{
@@ -121,4 +122,4 @@ protected virtual string ForeignKeysSchemaName
 
 		#endregion
 	}
-}
+}

src/NHibernate/Dialect/Schema/SybaseAnywhereMetaData.cs

@@ -18,7 +18,7 @@ public override ITableMetadata GetTableMetadata(DataRow rs, bool extras)
 
 		public override ISet<string> GetReservedWords()
 		{
-			var result = new HashSet<string>();
+			var result = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
 			DataTable dtReservedWords = Connection.GetSchema(DbMetaDataCollectionNames.ReservedWords);
 			foreach (DataRow row in dtReservedWords.Rows)
 			{
@@ -143,4 +143,4 @@ public SybaseAnywhereForeignKeyMetaData(DataRow rs) : base(rs)
 			Name = (string) rs["COLUMN_NAME"];
 		}
 	}
-}
+}

src/NHibernate/SqlCommand/Template.cs

@@ -308,7 +308,7 @@ private static bool IsFunctionOrKeyword(string lcToken, string nextToken, Dialec
 			return "(".Equals(nextToken) ||
 			       Keywords.Contains(lcToken) ||
 			       functionRegistry.HasFunction(lcToken) ||
-			       dialect.Keywords.Contains(lcToken) ||
+			       dialect.IsKeyword(lcToken) ||
 				   dialect.IsKnownToken(lcToken, nextToken) ||
 			       FunctionKeywords.Contains(lcToken);
 		}
@@ -321,4 +321,4 @@ private static bool IsIdentifier(string token, Dialect.Dialect dialect)
 			                          );
 		}
 	}
-}
+}

src/NHibernate/Tool/hbm2ddl/SchemaMetadataUpdater.cs

@@ -3,7 +3,6 @@
 using NHibernate.Engine;
 using NHibernate.Mapping;
 using System.Collections.Generic;
-using NHibernate.Connection;
 
 namespace NHibernate.Tool.hbm2ddl
 {
@@ -12,95 +11,71 @@ public static class SchemaMetadataUpdater
 	{
 		public static void Update(ISessionFactoryImplementor sessionFactory)
 		{
-			var reservedWords = GetReservedWords(sessionFactory.ConnectionProvider, sessionFactory.Dialect);
-			sessionFactory.Dialect.Keywords.UnionWith(reservedWords);
+			UpdateDialectKeywords(
+				sessionFactory.Dialect,
+				new SuppliedConnectionProviderConnectionHelper(sessionFactory.ConnectionProvider));
 		}
 
 		public static void Update(Configuration configuration, Dialect.Dialect dialect)
 		{
-			dialect.Keywords.UnionWith(GetReservedWords(configuration, dialect));
+			UpdateDialectKeywords(
+				dialect,
+				new ManagedProviderConnectionHelper(configuration.GetDerivedProperties()));
 		}
 
-		[Obsolete("Use the overload that passes dialect so keywords will be updated and persisted before auto-quoting")]
-		public static void QuoteTableAndColumns(Configuration configuration)
-		{
-			// Instantiates a new instance of the dialect so doesn't benefit from the Update call.
-			var dialect = Dialect.Dialect.GetDialect(configuration.GetDerivedProperties());
-			Update(configuration, dialect);
-			QuoteTableAndColumns(configuration, dialect);
-		}
-
-		public static void QuoteTableAndColumns(Configuration configuration, Dialect.Dialect dialect)
+		static void UpdateDialectKeywords(Dialect.Dialect dialect, IConnectionHelper connectionHelper)
 		{
-			ISet<string> reservedDb = dialect.Keywords;
-
-			foreach (var cm in configuration.ClassMappings)
-			{
-				QuoteTable(cm.Table, reservedDb);
-			}
-			foreach (var cm in configuration.CollectionMappings)
-			{
-				QuoteTable(cm.Table, reservedDb);
-			}
+			dialect.RegisterKeywords(GetReservedWords(dialect, connectionHelper));
 		}
 
-		private static ISet<string> GetReservedWords(Configuration configuration, Dialect.Dialect dialect)
+		static IEnumerable<string> GetReservedWords(Dialect.Dialect dialect, IConnectionHelper connectionHelper)
 		{
-			IConnectionHelper connectionHelper = new ManagedProviderConnectionHelper(configuration.GetDerivedProperties());
 			connectionHelper.Prepare();
 			try
 			{
-				return GetReservedWords(dialect, connectionHelper);
+				var metaData = dialect.GetDataBaseSchema(connectionHelper.Connection);
+				return metaData.GetReservedWords();
 			}
 			finally
 			{
 				connectionHelper.Release();
 			}
 		}
 
-		private static ISet<string> GetReservedWords(IConnectionProvider connectionProvider, Dialect.Dialect dialect)
+		[Obsolete("Use the overload that passes dialect so keywords will be updated and persisted before auto-quoting")]
+		public static void QuoteTableAndColumns(Configuration configuration)
 		{
-			IConnectionHelper connectionHelper = new SuppliedConnectionProviderConnectionHelper(connectionProvider);
-			connectionHelper.Prepare();
-			try
-			{
-				return GetReservedWords(dialect, connectionHelper);
-			}
-			finally
-			{
-				connectionHelper.Release();
-			}
+			// Instantiates a new instance of the dialect so doesn't benefit from the Update call.
+			var dialect = Dialect.Dialect.GetDialect(configuration.GetDerivedProperties());
+			Update(configuration, dialect);
+			QuoteTableAndColumns(configuration, dialect);
 		}
 
-		private static ISet<string> GetReservedWords(Dialect.Dialect dialect, IConnectionHelper connectionHelper)
+		public static void QuoteTableAndColumns(Configuration configuration, Dialect.Dialect dialect)
 		{
-			ISet<string> reservedWords = new HashSet<string>(dialect.Keywords, StringComparer.OrdinalIgnoreCase);
-			var metaData = dialect.GetDataBaseSchema(connectionHelper.Connection);
-			foreach (var rw in metaData.GetReservedWords())
+			foreach (var cm in configuration.ClassMappings)
 			{
-				reservedWords.Add(rw);
+				QuoteTable(cm.Table, dialect);
+			}
+			foreach (var cm in configuration.CollectionMappings)
+			{
+				QuoteTable(cm.Table, dialect);
 			}
-			return reservedWords;
 		}
 
-		private static void QuoteTable(Table table, ICollection<string> reservedDb)
+		private static void QuoteTable(Table table, Dialect.Dialect dialect)
 		{
-			if (!table.IsQuoted && reservedDb.Contains(table.Name))
+			if (!table.IsQuoted && dialect.IsKeyword(table.Name))
 			{
-				table.Name = GetNhQuoted(table.Name);
+				table.IsQuoted = true;
 			}
 			foreach (var column in table.ColumnIterator)
 			{
-				if (!column.IsQuoted && reservedDb.Contains(column.Name))
+				if (!column.IsQuoted && dialect.IsKeyword(column.Name))
 				{
-					column.Name = GetNhQuoted(column.Name);
+					column.IsQuoted = true;
 				}
 			}
 		}
-
-		private static string GetNhQuoted(string name)
-		{
-			return "`" + name + "`";
-		}
 	}
-}
+}