Refactor SqlConstraintString

Author: hazzik

src/NHibernate/Mapping/ForeignKey.cs

@@ -27,29 +27,26 @@ public class ForeignKey : Constraint
 		/// <returns>
 		/// A string that contains the SQL to create the named Foreign Key Constraint.
 		/// </returns>
-		public override string SqlConstraintString(Dialect.Dialect d, string constraintName, string defaultCatalog, string defaultSchema)
-		{
-			string[] cols = new string[ColumnSpan];
-			string[] refcols = new string[ColumnSpan];
-			int i = 0;
-			IEnumerable<Column> refiter;
-			if (IsReferenceToPrimaryKey)
-				refiter = referencedTable.PrimaryKey.ColumnIterator;
-			else
-				refiter = referencedColumns ?? Enumerable.Empty<Column>();
-			foreach (Column column in ColumnIterator)
-			{
-				cols[i] = column.GetQuotedName(d);
-				i++;
-			}
+		public override string SqlConstraintString(
+			Dialect.Dialect d,
+			string constraintName,
+			string defaultCatalog,
+			string defaultSchema)
+		{
+			var refiter = IsReferenceToPrimaryKey
+				? referencedTable.PrimaryKey.Columns
+				: referencedColumns;
+
+			var cols = Columns.ToArray(column => column.GetQuotedName(d));
+			var refcols = refiter.ToArray(column => column.GetQuotedName(d));
+
+			string result = d.GetAddForeignKeyConstraintString(
+				constraintName,
+				cols,
+				referencedTable.GetQualifiedName(d, defaultCatalog, defaultSchema),
+				refcols,
+				IsReferenceToPrimaryKey);
 
-			i = 0;
-			foreach (Column column in refiter)
-			{
-				refcols[i] = column.GetQuotedName(d);
-				i++;
-			}
-			string result = d.GetAddForeignKeyConstraintString(constraintName, cols, referencedTable.GetQualifiedName(d, defaultCatalog, defaultSchema), refcols, IsReferenceToPrimaryKey);
 			return cascadeDeleteEnabled && d.SupportsCascadeDelete ? result + " on delete cascade" : result;
 		}
 
@@ -217,10 +214,7 @@ public string ReferencedEntityName
 		}
 
 		/// <summary>Does this foreignkey reference the primary key of the reference table </summary>
-		public bool IsReferenceToPrimaryKey
-		{
-			get { return referencedColumns == null || referencedColumns.Count == 0; }
-		}
+		public bool IsReferenceToPrimaryKey => referencedColumns == null || referencedColumns.Count == 0;
 
 		public string GeneratedConstraintNamePrefix => "FK_";
 
@@ -231,12 +225,7 @@ public override bool IsGenerated(Dialect.Dialect dialect)
 			if (dialect.SupportsNullInUnique || IsReferenceToPrimaryKey)
 				return true;
 
-			foreach (var column in referencedColumns)
-			{
-				if (column.IsNullable)
-					return false;
-			}
-			return true;
+			return referencedColumns.All(column => !column.IsNullable);
 		}
 	}
 }