Refactor & optimize ProjectionExpression, TranslatedQuery (#40)

Orm/Xtensive.Orm/Core/ParameterContext.cs

@@ -1,4 +1,4 @@
-// Copyright (C) 2008-2020 Xtensive LLC.
+// Copyright (C) 2008-2021 Xtensive LLC.
 // This code is distributed under MIT license terms.
 // See the License.txt file in the project root for more information.
 // Created by: Alex Kofman
@@ -7,7 +7,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-
+using Tuple = Xtensive.Tuples.Tuple;
 
 namespace Xtensive.Core
 {
@@ -42,9 +42,15 @@ public TValue GetValue<TValue>(Parameter<TValue> parameter)
     /// <summary>
     /// Initializes new instance of this type.
     /// </summary>
-    public ParameterContext(ParameterContext outerContext = null)
+    public ParameterContext(ParameterContext outerContext = null, IReadOnlyDictionary<Parameter<Tuple>, Tuple> tupleParameterBindings = null)
     {
       this.outerContext = outerContext;
+
+      if (tupleParameterBindings != null) {
+        foreach (var (parameter, tuple) in tupleParameterBindings) {
+          SetValue(parameter, tuple);
+        }
+      }
     }
   }
 }

Orm/Xtensive.Orm/Orm/DelayedQuery.cs

@@ -97,10 +97,7 @@ internal DelayedQuery(Session session, TranslatedQuery translatedQuery, Paramete
       LifetimeToken = session.GetLifetimeToken();
 
       materializer = translatedQuery.Materializer;
-      parameterContext = new ParameterContext(outerParameterContext);
-      foreach (var (parameter, tuple) in translatedQuery.TupleParameterBindings) {
-        parameterContext.SetValue(parameter, tuple);
-      }
+      parameterContext = new ParameterContext(outerParameterContext, translatedQuery.TupleParameterBindings);
 
       Task = new QueryTask(translatedQuery.DataSource, LifetimeToken, parameterContext);
     }

Orm/Xtensive.Orm/Orm/Linq/Expressions/GroupingExpression.cs

@@ -90,11 +90,7 @@ public override Expression ReplaceApplyParameter(ApplyParameter newApplyParamete
         return new GroupingExpression(Type, OuterParameter, DefaultIfEmpty, ProjectionExpression, ApplyParameter, KeyExpression, SelectManyInfo);
 
       var newItemProjector = ProjectionExpression.ItemProjector.RewriteApplyParameter(ApplyParameter, newApplyParameter);
-      var newProjectionExpression = new ProjectionExpression(
-        ProjectionExpression.Type, 
-        newItemProjector, 
-        ProjectionExpression.TupleParameterBindings, 
-        ProjectionExpression.ResultAccessMethod);
+      var newProjectionExpression = ProjectionExpression.Apply(newItemProjector);
       return new GroupingExpression(Type, OuterParameter, DefaultIfEmpty, newProjectionExpression, newApplyParameter, KeyExpression, SelectManyInfo);
     }
 

Orm/Xtensive.Orm/Orm/Linq/Expressions/ProjectionExpression.cs

@@ -1,4 +1,4 @@
-// Copyright (C) 2008-2020 Xtensive LLC.
+// Copyright (C) 2008-2021 Xtensive LLC.
 // This code is distributed under MIT license terms.
 // See the License.txt file in the project root for more information.
 // Created by: Alexey Kochetov
@@ -13,40 +13,29 @@ namespace Xtensive.Orm.Linq.Expressions
 {
   internal class ProjectionExpression : ExtendedExpression
   {
-    public ItemProjectorExpression ItemProjector { get; private set;}
-    public ResultAccessMethod ResultAccessMethod { get; private set; }
-    public Dictionary<Parameter<Tuple>, Tuple> TupleParameterBindings { get; private set; }
+    public ItemProjectorExpression ItemProjector { get; }
+    public ResultAccessMethod ResultAccessMethod { get; }
+    public IReadOnlyDictionary<Parameter<Tuple>, Tuple> TupleParameterBindings { get; }
 
-    public bool IsScalar
-    {
-      get {  return ResultAccessMethod != ResultAccessMethod.All; }
-    }
+    public bool IsScalar => ResultAccessMethod != ResultAccessMethod.All;
 
-    public override string ToString()
-    {
-      return $"Projection:  {ItemProjector}, IsScalar = {IsScalar}";
-    }
+    public override string ToString() => $"Projection:  {ItemProjector}, IsScalar = {IsScalar}";
 
+    public ProjectionExpression Apply(ItemProjectorExpression itemProjectorExpression) =>
+      new ProjectionExpression(Type, itemProjectorExpression, TupleParameterBindings, ResultAccessMethod);
 
     // Constructors
 
     public ProjectionExpression(
       Type type,
       ItemProjectorExpression itemProjectorExpression,
-      IReadOnlyDictionary<Parameter<Tuple>, Tuple> tupleParameterBindings)
-      : this(type, itemProjectorExpression, tupleParameterBindings, ResultAccessMethod.All)
-    {}
-
-    public ProjectionExpression(
-      Type type, 
-      ItemProjectorExpression itemProjectorExpression,
-      IReadOnlyDictionary<Parameter<Tuple>, Tuple> tupleParameterBindings, 
-      ResultAccessMethod resultAccessMethod)
+      IReadOnlyDictionary<Parameter<Tuple>, Tuple> tupleParameterBindings,
+      ResultAccessMethod resultAccessMethod = ResultAccessMethod.All)
       : base(ExtendedExpressionType.Projection, type)
     {
       ItemProjector = itemProjectorExpression;
       ResultAccessMethod = resultAccessMethod;
-      TupleParameterBindings = new Dictionary<Parameter<Tuple>, Tuple>(tupleParameterBindings);
+      TupleParameterBindings = tupleParameterBindings;
     }
   }
-}
+}

Orm/Xtensive.Orm/Orm/Linq/Expressions/SubQueryExpression.cs

@@ -1,4 +1,4 @@
-// Copyright (C) 2009-2020 Xtensive LLC.
+// Copyright (C) 2009-2021 Xtensive LLC.
 // This code is distributed under MIT license terms.
 // See the License.txt file in the project root for more information.
 // Created by: Alexey Gamzov
@@ -19,9 +19,9 @@ namespace Xtensive.Orm.Linq.Expressions
   internal class SubQueryExpression : ParameterizedExpression,
     IMappedExpression
   {
-    public ProjectionExpression ProjectionExpression { get; private set; }
+    public ProjectionExpression ProjectionExpression { get; }
 
-    public ApplyParameter ApplyParameter { get; private set; }
+    public ApplyParameter ApplyParameter { get; }
 
     public virtual Expression BindParameter(ParameterExpression parameter, Dictionary<Expression, Expression> processedExpressions)
     {
@@ -105,15 +105,11 @@ public virtual Expression Remap(IReadOnlyList<int> map, Dictionary<Expression, E
 
     public virtual Expression ReplaceApplyParameter(ApplyParameter newApplyParameter)
     {
-      if (newApplyParameter==ApplyParameter)
+      if (newApplyParameter == ApplyParameter)
         return new SubQueryExpression(Type, OuterParameter, DefaultIfEmpty, ProjectionExpression, ApplyParameter);
 
       var newItemProjector = ProjectionExpression.ItemProjector.RewriteApplyParameter(ApplyParameter, newApplyParameter);
-      var newProjectionExpression = new ProjectionExpression(
-        ProjectionExpression.Type, 
-        newItemProjector, 
-        ProjectionExpression.TupleParameterBindings, 
-        ProjectionExpression.ResultAccessMethod);
+      var newProjectionExpression = ProjectionExpression.Apply(newItemProjector);
       return new SubQueryExpression(Type, OuterParameter, DefaultIfEmpty, newProjectionExpression, newApplyParameter);
     }
 

Orm/Xtensive.Orm/Orm/Linq/Expressions/Visitors/ExtendedExpressionReplacer.cs

@@ -34,15 +34,11 @@ protected override Expression VisitProjectionExpression(ProjectionExpression pro
     {
       var item = Visit(projectionExpression.ItemProjector.Item);
       var provider = providerVisitor.VisitCompilable(projectionExpression.ItemProjector.DataSource);
-      var providerChanged = provider!=projectionExpression.ItemProjector.DataSource;
-      var itemChanged = item!=projectionExpression.ItemProjector.Item;
+      var providerChanged = provider != projectionExpression.ItemProjector.DataSource;
+      var itemChanged = item != projectionExpression.ItemProjector.Item;
       if (providerChanged || itemChanged) {
         var itemProjector = new ItemProjectorExpression(item, provider, projectionExpression.ItemProjector.Context);
-        return new ProjectionExpression(
-          projectionExpression.Type,
-          itemProjector,
-          projectionExpression.TupleParameterBindings,
-          projectionExpression.ResultAccessMethod);
+        return projectionExpression.Apply(itemProjector);
       }
       return projectionExpression;
     }

Orm/Xtensive.Orm/Orm/Linq/LinqBindingCollection.cs

@@ -66,11 +66,7 @@ public override void ReplaceBound(ParameterExpression key, ProjectionExpression
           if (parameter!=key) {
             var projection = this[parameter];
             var newItemProjector = projection.ItemProjector.Remap(value.ItemProjector.DataSource, 0);
-            var newProjection = new ProjectionExpression(
-              projection.Type, 
-              newItemProjector, 
-              projection.TupleParameterBindings, 
-              projection.ResultAccessMethod);
+            var newProjection = projection.Apply(newItemProjector);
             base.ReplaceBound(parameter, newProjection);
           }
         }

Orm/Xtensive.Orm/Orm/Linq/Materialization/ExpressionMaterializer.cs

@@ -161,9 +161,11 @@ protected override Expression VisitSubQueryExpression(SubQueryExpression subQuer
 
     private TranslatedQuery PrepareSubqueryParameters(SubQueryExpression subQueryExpression, out Parameter<Tuple> parameterOfTuple, out Type elementType, out ProjectionExpression projection)
     {
+      var projectionExpression = subQueryExpression.ProjectionExpression;
+
       // 1. Rewrite recordset and ItemProjector to parameter<tuple>
       var subqueryTupleParameter = context.GetTupleParameter(subQueryExpression.OuterParameter);
-      var dataSource = subQueryExpression.ProjectionExpression.ItemProjector.DataSource;
+      var dataSource = projectionExpression.ItemProjector.DataSource;
 
       var rootTags = context.GetAllTags();
       if (rootTags.Count > 0) {
@@ -176,27 +178,20 @@ private TranslatedQuery PrepareSubqueryParameters(SubQueryExpression subQueryExp
         subQueryExpression.ApplyParameter);
 
       var newItemProjectorBody = ApplyParameterToTupleParameterRewriter.Rewrite(
-        subQueryExpression.ProjectionExpression.ItemProjector.Item,
+        projectionExpression.ItemProjector.Item,
         subqueryTupleParameter,
         subQueryExpression.ApplyParameter);
 
-      var itemProjector = new ItemProjectorExpression(newItemProjectorBody, newDataSource, subQueryExpression.ProjectionExpression.ItemProjector.Context);
+      var itemProjector = new ItemProjectorExpression(newItemProjectorBody, newDataSource, projectionExpression.ItemProjector.Context);
       parameterOfTuple = context.GetTupleParameter(subQueryExpression.OuterParameter);
 
       // 2. Add only parameter<tuple>. Tuple value will be assigned
       // at the moment of materialization in SubQuery constructor
-      projection = new ProjectionExpression(
-        subQueryExpression.ProjectionExpression.Type,
-        itemProjector,
-        subQueryExpression.ProjectionExpression.TupleParameterBindings,
-        subQueryExpression.ProjectionExpression.ResultAccessMethod);
-
-      // 3. Make translation
-      elementType = subQueryExpression.ProjectionExpression.ItemProjector.Item.Type;
-      var translateMethod = Translator.TranslateMethod;
-      return (TranslatedQuery) translateMethod.Invoke(
-        context.Translator,
-        new object[] {projection, tupleParameters.Append(parameterOfTuple)});
+      projection = projectionExpression.Apply(itemProjector);
+
+      // 3. Make translation 
+      elementType = projectionExpression.ItemProjector.Item.Type;
+      return context.Translator.Translate(projection, tupleParameters.Append(parameterOfTuple));
     }
 
     protected override Expression VisitFieldExpression(FieldExpression expression)

Orm/Xtensive.Orm/Orm/Linq/Rewriters/ApplyParameterRewriter.cs

@@ -1,4 +1,4 @@
-// Copyright (C) 2009-2020 Xtensive LLC.
+// Copyright (C) 2009-2021 Xtensive LLC.
 // This code is distributed under MIT license terms.
 // See the License.txt file in the project root for more information.
 // Created by: Alexey Gamzov
@@ -40,18 +40,15 @@ protected override Expression VisitMemberAccess(MemberExpression m)
 
     protected override Expression VisitGroupingExpression(GroupingExpression expression)
     {
-      var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, oldApplyParameter, newApplyParameter);
-      var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
+      var projectionExpression = expression.ProjectionExpression;
+      var newProvider = Rewrite(projectionExpression.ItemProjector.DataSource, oldApplyParameter, newApplyParameter);
+      var newItemProjectorBody = Visit(projectionExpression.ItemProjector.Item);
       var newKeyExpression = Visit(expression.KeyExpression);
-      if (newProvider!=expression.ProjectionExpression.ItemProjector.DataSource
-        || newItemProjectorBody!=expression.ProjectionExpression.ItemProjector.Item
-          || newKeyExpression!=expression.KeyExpression) {
-        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
-        var newProjectionExpression = new ProjectionExpression(
-          expression.ProjectionExpression.Type, 
-          newItemProjector, 
-          expression.ProjectionExpression.TupleParameterBindings, 
-          expression.ProjectionExpression.ResultAccessMethod);
+      if (newProvider != projectionExpression.ItemProjector.DataSource
+        || newItemProjectorBody != projectionExpression.ItemProjector.Item
+          || newKeyExpression != expression.KeyExpression) {
+        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, projectionExpression.ItemProjector.Context);
+        var newProjectionExpression = projectionExpression.Apply(newItemProjector);
         return new GroupingExpression(
           expression.Type, expression.OuterParameter, expression.DefaultIfEmpty, newProjectionExpression,
           expression.ApplyParameter, expression.KeyExpression, expression.SelectManyInfo);
@@ -61,17 +58,14 @@ protected override Expression VisitGroupingExpression(GroupingExpression express
 
     protected override Expression VisitSubQueryExpression(SubQueryExpression expression)
     {
-      var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, oldApplyParameter, newApplyParameter);
-      var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
-      if (newProvider!=expression.ProjectionExpression.ItemProjector.DataSource
-        || newItemProjectorBody!=expression.ProjectionExpression.ItemProjector.Item) {
+      var projectionExpression = expression.ProjectionExpression;
+      var newProvider = Rewrite(projectionExpression.ItemProjector.DataSource, oldApplyParameter, newApplyParameter);
+      var newItemProjectorBody = Visit(projectionExpression.ItemProjector.Item);
+      if (newProvider != projectionExpression.ItemProjector.DataSource
+        || newItemProjectorBody != projectionExpression.ItemProjector.Item) {
         var newItemProjector = new ItemProjectorExpression(
-          newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
-        var newProjectionExpression = new ProjectionExpression(
-          expression.ProjectionExpression.Type, 
-          newItemProjector, 
-          expression.ProjectionExpression.TupleParameterBindings, 
-          expression.ProjectionExpression.ResultAccessMethod);
+          newItemProjectorBody, newProvider, projectionExpression.ItemProjector.Context);
+        var newProjectionExpression = projectionExpression.Apply(newItemProjector);
         return new SubQueryExpression(
           expression.Type, expression.OuterParameter, expression.DefaultIfEmpty, newProjectionExpression,
           expression.ApplyParameter, expression.ExtendedType);

Orm/Xtensive.Orm/Orm/Linq/Rewriters/ApplyParameterToTupleParameterRewriter.cs

@@ -41,18 +41,15 @@ protected override Expression VisitMemberAccess(MemberExpression m)
 
     protected override Expression VisitGroupingExpression(GroupingExpression expression)
     {
-      var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, parameterOfTuple, applyParameter);
-      var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
+      var projectionExpression = expression.ProjectionExpression;
+      var newProvider = Rewrite(projectionExpression.ItemProjector.DataSource, parameterOfTuple, applyParameter);
+      var newItemProjectorBody = Visit(projectionExpression.ItemProjector.Item);
       var newKeyExpression = Visit(expression.KeyExpression);
-      if (newProvider!=expression.ProjectionExpression.ItemProjector.DataSource
-        || newItemProjectorBody!=expression.ProjectionExpression.ItemProjector.Item
-          || newKeyExpression!=expression.KeyExpression) {
-        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
-        var newProjectionExpression = new ProjectionExpression(
-          expression.ProjectionExpression.Type, 
-          newItemProjector, 
-          expression.ProjectionExpression.TupleParameterBindings, 
-          expression.ProjectionExpression.ResultAccessMethod);
+      if (newProvider != projectionExpression.ItemProjector.DataSource
+        || newItemProjectorBody != projectionExpression.ItemProjector.Item
+          || newKeyExpression != expression.KeyExpression) {
+        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, projectionExpression.ItemProjector.Context);
+        var newProjectionExpression = projectionExpression.Apply(newItemProjector);
         return new GroupingExpression(
           expression.Type, expression.OuterParameter, expression.DefaultIfEmpty,
           newProjectionExpression, expression.ApplyParameter,
@@ -63,15 +60,12 @@ protected override Expression VisitGroupingExpression(GroupingExpression express
 
     protected override Expression VisitSubQueryExpression(SubQueryExpression expression)
     {
-      var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, parameterOfTuple, applyParameter);
-      var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
-      if (newProvider!=expression.ProjectionExpression.ItemProjector.DataSource || newItemProjectorBody!=expression.ProjectionExpression.ItemProjector.Item) {
-        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
-        var newProjectionExpression = new ProjectionExpression(
-          expression.ProjectionExpression.Type, 
-          newItemProjector, 
-          expression.ProjectionExpression.TupleParameterBindings, 
-          expression.ProjectionExpression.ResultAccessMethod);
+      var projectionExpression = expression.ProjectionExpression;
+      var newProvider = Rewrite(projectionExpression.ItemProjector.DataSource, parameterOfTuple, applyParameter);
+      var newItemProjectorBody = Visit(projectionExpression.ItemProjector.Item);
+      if (newProvider != projectionExpression.ItemProjector.DataSource || newItemProjectorBody != projectionExpression.ItemProjector.Item) {
+        var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, projectionExpression.ItemProjector.Context);
+        var newProjectionExpression = projectionExpression.Apply(newItemProjector);
         return new SubQueryExpression(
           expression.Type, expression.OuterParameter,
           expression.DefaultIfEmpty, newProjectionExpression,