Simplify and minimize expression containers. (#448)

Author: fiseni

src/Ardalis.Specification.EntityFramework6/Extensions/IncludeExtensions.cs

@@ -16,7 +16,6 @@ public static IQueryable<T> Include<T>(this IQueryable<T> source, IncludeExpress
     public static IQueryable<T> ThenInclude<T>(this IQueryable<T> source, IncludeExpressionInfo info)
     {
         _ = info ?? throw new ArgumentNullException(nameof(info));
-        _ = info.PreviousPropertyType ?? throw new ArgumentNullException(nameof(info.PreviousPropertyType));
 
         var exp = source.Expression as MethodCallExpression;
         var arg = exp.Arguments[0] as ConstantExpression;
@@ -47,7 +46,7 @@ public static IQueryable<T> ThenInclude<T>(this IQueryable<T> source, IncludeExp
         return QueryableExtensions.Include(source, $"{previousPropertyName}.{propertyName}");
     }
 
-    private static string GetPropertyName(this Expression propertySelector, char delimiter = '.', char endTrim = ')')
+    private static string GetPropertyName(this LambdaExpression propertySelector, char delimiter = '.', char endTrim = ')')
     {
 
         var asString = propertySelector.ToString();

src/Ardalis.Specification/Builders/Builder_Include.cs

@@ -101,7 +101,7 @@ public static IIncludableSpecificationBuilder<T, TResult, TProperty> Include<T,
     {
         if (condition)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(T), typeof(TProperty));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.Include);
             builder.Specification.Add(expr);
         }
 
@@ -139,7 +139,7 @@ public static IIncludableSpecificationBuilder<T, TProperty> Include<T, TProperty
     {
         if (condition)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(T), typeof(TProperty));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.Include);
             builder.Specification.Add(expr);
         }
 
@@ -183,7 +183,7 @@ public static IIncludableSpecificationBuilder<TEntity, TResult, TProperty> ThenI
     {
         if (condition && !Specification<TEntity, TResult>.IsChainDiscarded)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(TEntity), typeof(TProperty), typeof(TPreviousProperty));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.ThenInclude);
             builder.Specification.Add(expr);
         }
         else
@@ -228,7 +228,7 @@ public static IIncludableSpecificationBuilder<TEntity, TProperty> ThenInclude<TE
     {
         if (condition && !Specification<TEntity>.IsChainDiscarded)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(TEntity), typeof(TProperty), typeof(TPreviousProperty));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.ThenInclude);
             builder.Specification.Add(expr);
         }
         else
@@ -275,7 +275,7 @@ public static IIncludableSpecificationBuilder<TEntity, TResult, TProperty> ThenI
     {
         if (condition && !Specification<TEntity, TResult>.IsChainDiscarded)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(TEntity), typeof(TProperty), typeof(IEnumerable<TPreviousProperty>));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.ThenInclude);
             builder.Specification.Add(expr);
         }
         else
@@ -320,7 +320,7 @@ public static IIncludableSpecificationBuilder<TEntity, TProperty> ThenInclude<TE
     {
         if (condition && !Specification<TEntity>.IsChainDiscarded)
         {
-            var expr = new IncludeExpressionInfo(navigationSelector, typeof(TEntity), typeof(TProperty), typeof(IEnumerable<TPreviousProperty>));
+            var expr = new IncludeExpressionInfo(navigationSelector, IncludeTypeEnum.ThenInclude);
             builder.Specification.Add(expr);
         }
         else

src/Ardalis.Specification/Expressions/IncludeExpressionInfo.cs

@@ -11,76 +11,16 @@ public class IncludeExpressionInfo
     /// </summary>
     public LambdaExpression LambdaExpression { get; }
 
-    /// <summary>
-    /// The type of the source entity.
-    /// </summary>
-    public Type EntityType { get; }
-
-    /// <summary>
-    /// The type of the included entity.
-    /// </summary>
-    public Type PropertyType { get; }
-
-    /// <summary>
-    /// The type of the previously included entity.
-    /// </summary>
-    public Type? PreviousPropertyType { get; }
-
     /// <summary>
     /// The include type.
     /// </summary>
     public IncludeTypeEnum Type { get; }
 
-    private IncludeExpressionInfo(LambdaExpression expression,
-                                  Type entityType,
-                                  Type propertyType,
-                                  Type? previousPropertyType,
-                                  IncludeTypeEnum includeType)
-
+    public IncludeExpressionInfo(LambdaExpression expression, IncludeTypeEnum includeType)
     {
         _ = expression ?? throw new ArgumentNullException(nameof(expression));
-        _ = entityType ?? throw new ArgumentNullException(nameof(entityType));
-        _ = propertyType ?? throw new ArgumentNullException(nameof(propertyType));
-
-        if (includeType == IncludeTypeEnum.ThenInclude)
-        {
-            _ = previousPropertyType ?? throw new ArgumentNullException(nameof(previousPropertyType));
-        }
 
         LambdaExpression = expression;
-        EntityType = entityType;
-        PropertyType = propertyType;
-        PreviousPropertyType = previousPropertyType;
         Type = includeType;
     }
-
-    /// <summary>
-    /// Creates instance of <see cref="IncludeExpressionInfo" /> which describes 'Include' query part.<para />
-    /// Source (entityType) -> Include (propertyType).
-    /// </summary>
-    /// <param name="expression">The expression represents a related entity that should be included.</param>
-    /// <param name="entityType">The type of the source entity.</param>
-    /// <param name="propertyType">The type of the included entity.</param>
-    public IncludeExpressionInfo(LambdaExpression expression,
-                                 Type entityType,
-                                 Type propertyType)
-        : this(expression, entityType, propertyType, null, IncludeTypeEnum.Include)
-    {
-    }
-
-    /// <summary>
-    /// Creates instance of <see cref="IncludeExpressionInfo" /> which describes 'ThenInclude' query part.<para />
-    /// Source (entityType) -> Include (previousPropertyType) -> ThenInclude (propertyType).
-    /// </summary>
-    /// <param name="expression">The expression represents a related entity that should be included as part of the previously included entity.</param>
-    /// <param name="entityType">The type of the source entity.</param>
-    /// <param name="propertyType">The type of the included entity.</param>
-    /// <param name="previousPropertyType">The type of the previously included entity.</param>
-    public IncludeExpressionInfo(LambdaExpression expression,
-                                 Type entityType,
-                                 Type propertyType,
-                                 Type previousPropertyType)
-        : this(expression, entityType, propertyType, previousPropertyType, IncludeTypeEnum.ThenInclude)
-    {
-    }
 }

src/Ardalis.Specification/Expressions/OrderExpressionInfo.cs

@@ -6,7 +6,7 @@
 /// <typeparam name="T">Type of the entity to apply sort on.</typeparam>
 public class OrderExpressionInfo<T>
 {
-    private readonly Lazy<Func<T, object?>> _keySelectorFunc;
+    private Func<T, object?>? _keySelectorFunc;
 
     /// <summary>
     /// Creates instance of <see cref="OrderExpressionInfo{T}" />.
@@ -20,8 +20,6 @@ public OrderExpressionInfo(Expression<Func<T, object?>> keySelector, OrderTypeEn
 
         KeySelector = keySelector;
         OrderType = orderType;
-
-        _keySelectorFunc = new Lazy<Func<T, object?>>(KeySelector.Compile);
     }
 
     /// <summary>
@@ -37,5 +35,5 @@ public OrderExpressionInfo(Expression<Func<T, object?>> keySelector, OrderTypeEn
     /// <summary>
     /// Compiled <see cref="KeySelector" />.
     /// </summary>
-    public Func<T, object?> KeySelectorFunc => _keySelectorFunc.Value;
+    public Func<T, object?> KeySelectorFunc => _keySelectorFunc ??= KeySelector.Compile();
 }

src/Ardalis.Specification/Expressions/SearchExpressionInfo.cs

@@ -6,7 +6,7 @@
 /// <typeparam name="T">Type of the source from which search target should be selected.</typeparam>
 public class SearchExpressionInfo<T>
 {
-    private readonly Lazy<Func<T, string?>> _selectorFunc;
+    private Func<T, string?>? _selectorFunc;
 
     /// <summary>
     /// Creates instance of <see cref="SearchExpressionInfo{T}" />.
@@ -24,8 +24,6 @@ public SearchExpressionInfo(Expression<Func<T, string?>> selector, string search
         Selector = selector;
         SearchTerm = searchTerm;
         SearchGroup = searchGroup;
-
-        _selectorFunc = new Lazy<Func<T, string?>>(Selector.Compile);
     }
 
     /// <summary>
@@ -46,5 +44,5 @@ public SearchExpressionInfo(Expression<Func<T, string?>> selector, string search
     /// <summary>
     /// Compiled <see cref="Selector" />.
     /// </summary>
-    public Func<T, string?> SelectorFunc => _selectorFunc.Value;
+    public Func<T, string?> SelectorFunc => _selectorFunc ??= Selector.Compile();
 }

src/Ardalis.Specification/Expressions/WhereExpressionInfo.cs

@@ -6,7 +6,7 @@
 /// <typeparam name="T">Type of the entity to apply filter on.</typeparam>
 public class WhereExpressionInfo<T>
 {
-    private readonly Lazy<Func<T, bool>> _filterFunc;
+    private Func<T, bool>? _filterFunc;
 
     /// <summary>
     /// Creates instance of <see cref="WhereExpressionInfo{T}" />.
@@ -16,10 +16,7 @@ public class WhereExpressionInfo<T>
     public WhereExpressionInfo(Expression<Func<T, bool>> filter)
     {
         _ = filter ?? throw new ArgumentNullException(nameof(filter));
-
         Filter = filter;
-
-        _filterFunc = new Lazy<Func<T, bool>>(Filter.Compile);
     }
 
     /// <summary>
@@ -30,5 +27,5 @@ public WhereExpressionInfo(Expression<Func<T, bool>> filter)
     /// <summary>
     /// Compiled <see cref="Filter" />.
     /// </summary>
-    public Func<T, bool> FilterFunc => _filterFunc.Value;
+    public Func<T, bool> FilterFunc => _filterFunc ??= Filter.Compile();
 }