ToList() improvements

less enumerations, less resizing

Author: alex-kulakov

Orm/Xtensive.Orm/Orm/Building/Builders/IndexBuilder.cs

@@ -807,15 +807,15 @@ private ColumnGroup BuildColumnGroup(IndexInfo index)
     {
       var reflectedType = index.ReflectedType;
       var keyColumns = index.IsPrimary
-        ? Enumerable.Range(0, index.KeyColumns.Count).ToList()
+        ? Enumerable.Range(0, index.KeyColumns.Count).ToList(index.KeyColumns.Count)
         : index.KeyColumns
             .Select(pair => pair.Key)
             .Concat(index.ValueColumns)
             .Select((c, i) => (c, i))
             .Where(arg => arg.c.IsPrimaryKey)
             .Select(arg => arg.i)
             .ToList();
-      var columns = Enumerable.Range(0, index.KeyColumns.Count + index.ValueColumns.Count).ToList();
+      var columns = Enumerable.Range(0, index.KeyColumns.Count + index.ValueColumns.Count).ToList(index.KeyColumns.Count + index.ValueColumns.Count);
       return new ColumnGroup(reflectedType, keyColumns, columns);
     }
 

Orm/Xtensive.Orm/Orm/Building/BuildingContext.cs

@@ -85,7 +85,8 @@ internal BuildingContext(DomainBuilderConfiguration builderConfiguration)
       ModelInspectionResult = new ModelInspectionResult();
       DependencyGraph = new Graph<TypeDef>();
 
-      Modules = BuilderConfiguration.Services.Modules.ToList().AsReadOnly();
+      
+      Modules = BuilderConfiguration.Services.Modules.ToList(BuilderConfiguration.Services.Modules.Count).AsReadOnly();
       Modules2 = Modules.OfType<IModule2>().ToList().AsReadOnly();
       Validator = new Validator(builderConfiguration.Services.ProviderInfo.SupportedTypes);
       DefaultSchemaInfo = builderConfiguration.DefaultSchemaInfo;

Orm/Xtensive.Orm/Orm/Model/HierarchyInfo.cs

@@ -45,7 +45,7 @@ public override void UpdateState()
     {
       base.UpdateState();
       Key.UpdateState();
-      var list = new List<TypeInfo> {Root};
+      var list = new List<TypeInfo>(Root.AllDescendants.Count + 1) {Root};
       list.AddRange(Root.AllDescendants);
       Types = list.AsReadOnly();
       if (Types.Count == 1)

Orm/Xtensive.Orm/Orm/Model/PartialIndexFilterInfo.cs

@@ -1,4 +1,4 @@
-// Copyright (C) 2011 Xtensive LLC.
+// Copyright (C) 2011 Xtensive LLC.
 // All rights reserved.
 // For conditions of distribution and use, see license.
 // Created by: Denis Krjuchkov
@@ -56,7 +56,9 @@ public override void Lock(bool recursive)
         throw Exceptions.NotInitialized("Expression");
       if (Fields==null)
         throw Exceptions.NotInitialized("Fields");
-      fields = fields.ToList().AsReadOnly();
+      fields = fields is List<FieldInfo> list
+        ? list.AsReadOnly()
+        : (IList<FieldInfo>) fields.ToList().AsReadOnly();
       base.Lock(recursive);
     }
   }