Fix schema validator for Npgsql 5+

Author: hazzik

src/NHibernate.Test/NHibernate.Test.csproj

@@ -64,7 +64,7 @@
     <PackageReference Include="NUnit3TestAdapter" Version="4.1.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
     <PackageReference Include="FirebirdSql.Data.FirebirdClient" Version="8.5.2" />
-    <PackageReference Include="Npgsql" Version="4.1.9" />
+    <PackageReference Include="Npgsql" Version="6.0.2" />
     <PackageReference Include="MySql.Data" Version="8.0.27" />
   </ItemGroup>
   <ItemGroup Condition="$(NhNetFx)">

src/NHibernate/Dialect/Schema/PostgreSQLMetadata.cs

@@ -138,7 +138,39 @@ public PostgreSQLColumnMetadata(DataRow rs)
 			this.SetNumericalPrecision(rs["NUMERIC_PRECISION"]);
 
 			Nullable = Convert.ToString(rs["IS_NULLABLE"]);
-			TypeName = Convert.ToString(rs["DATA_TYPE"]);
+			TypeName = Normalize(Convert.ToString(rs["DATA_TYPE"]));
+		}
+
+		private static string Normalize(string typeName)
+		{
+			switch (typeName)
+			{
+				case "double precision":
+					return "float8";
+				case "real":
+					return "float4";
+				case "smallint":
+					return "int2";
+				case "integer":
+					return "int4";
+				case "bigint":
+					return "int8";
+			}
+
+			if (typeName.EndsWith("with timezone"))
+			{
+				return (typeName.StartsWith("timestamp")
+					       ? typeName.Replace("timestamp", "timestamptz")
+					       : typeName.Replace("time", "timetz"))
+				       .Replace("with timezone", "").Trim();
+			}
+
+			if (typeName.EndsWith("without timezone"))
+			{
+				return typeName.Replace("without timezone", "").Trim();
+			}
+			
+			return typeName;
 		}
 	}