Fixed issue with extracting predicates from IFilterContext. (#7693)

Author: michaelstaib

src/HotChocolate/Data/src/Data/Filters/Context/FilterContext.cs

@@ -67,7 +67,7 @@ public void Handled(bool isHandled)
         return null;
     }
 
-    private object? Serialize(IFilterValueNode? value)
+    private static object? Serialize(IFilterValueNode? value)
     {
         switch (value)
         {

src/HotChocolate/Data/src/Data/Filters/Context/FilterContextResolverContextExtensions.cs

@@ -33,8 +33,7 @@ context.LocalContextData[ContextValueNodeKey] is IValueNode node
             return null;
         }
 
-        FilterContext filterContext =
-            new(context, filterInput, filter, context.Service<InputParser>());
+        var filterContext = new FilterContext(context, filterInput, filter, context.Service<InputParser>());
 
         // disable the execution of filtering by default
         filterContext.Handled(true);

src/HotChocolate/Data/src/Data/Filters/Expressions/QueryableFilterProvider.cs

@@ -184,6 +184,18 @@ private ApplyFiltering CreateApplicator<TEntityType>(string argumentName)
         => (context, input) =>
         {
             var inMemory = IsInMemoryQuery<TEntityType>(input);
+
+            // if no filter is defined we can stop here and yield back control.
+            var skipFiltering = context.GetLocalStateOrDefault<bool>(SkipFilteringKey);
+
+            // ensure filtering is only applied once
+            context.SetLocalState(SkipFilteringKey, true);
+
+            if (skipFiltering)
+            {
+                return input;
+            }
+
             var predicate = AsPredicate<TEntityType>(context, argumentName, inMemory);
 
             if (predicate is not null)
@@ -205,13 +217,7 @@ private ApplyFiltering CreateApplicator<TEntityType>(string argumentName)
         var filter = context.GetLocalStateOrDefault<IValueNode>(ContextValueNodeKey) ??
             context.ArgumentLiteral<IValueNode>(argumentName);
 
-        // if no filter is defined we can stop here and yield back control.
-        var skipFiltering = context.GetLocalStateOrDefault<bool>(SkipFilteringKey);
-
-        // ensure filtering is only applied once
-        context.SetLocalState(SkipFilteringKey, true);
-
-        if (filter.IsNull() || skipFiltering)
+        if (filter.IsNull())
         {
             return null;
         }

src/HotChocolate/Data/src/Data/Filters/Extensions/QueryableExtensions.cs

@@ -0,0 +1,79 @@
+using HotChocolate.Data.Filters;
+using HotChocolate.Execution.Processing;
+
+// ReSharper disable once CheckNamespace
+namespace System.Linq;
+
+/// <summary>
+/// Provides extension methods to integrate <see cref="IQueryable{T}"/>
+/// with <see cref="ISelection"/> and <see cref="IFilterContext"/>.
+/// </summary>
+public static class QueryableExtensions
+{
+    /// <summary>
+    /// Applies a selection to the queryable.
+    /// </summary>
+    /// <param name="queryable">
+    /// The queryable that shall be projected.
+    /// </param>
+    /// <param name="selection">
+    /// The selection that shall be applied to the queryable.
+    /// </param>
+    /// <typeparam name="T">
+    /// The type of the queryable.
+    /// </typeparam>
+    /// <returns>
+    /// Returns a queryable that has the selection applied.
+    /// </returns>
+    /// <exception cref="ArgumentNullException">
+    /// Throws if <paramref name="queryable"/> is <c>null</c> or if <paramref name="selection"/> is <c>null</c>.
+    /// </exception>
+    public static IQueryable<T> Select<T>(this IQueryable<T> queryable, ISelection selection)
+    {
+        if (queryable is null)
+        {
+            throw new ArgumentNullException(nameof(queryable));
+        }
+
+        if (selection is null)
+        {
+            throw new ArgumentNullException(nameof(selection));
+        }
+
+        return queryable.Select(selection.AsSelector<T>());
+    }
+
+    /// <summary>
+    /// Applies a filter context to the queryable.
+    /// </summary>
+    /// <param name="queryable">
+    /// The queryable that shall be filtered.
+    /// </param>
+    /// <param name="filter">
+    /// The filter context that shall be applied to the queryable.
+    /// </param>
+    /// <typeparam name="T">
+    /// The type of the queryable.
+    /// </typeparam>
+    /// <returns>
+    /// Returns a queryable that has the filter applied.
+    /// </returns>
+    /// <exception cref="ArgumentNullException">
+    /// Throws if <paramref name="queryable"/> is <c>null</c> or if <paramref name="filter"/> is <c>null</c>.
+    /// </exception>
+    public static IQueryable<T> Where<T>(this IQueryable<T> queryable, IFilterContext filter)
+    {
+        if (queryable is null)
+        {
+            throw new ArgumentNullException(nameof(queryable));
+        }
+
+        if (filter is null)
+        {
+            throw new ArgumentNullException(nameof(filter));
+        }
+
+        var predicate = filter.AsPredicate<T>();
+        return predicate is null ? queryable : queryable.Where(predicate);
+    }
+}

src/HotChocolate/Data/src/Data/HotChocolate.Data.csproj

@@ -5,7 +5,7 @@
     <AssemblyName>HotChocolate.Data</AssemblyName>
     <RootNamespace>HotChocolate.Data</RootNamespace>
     <Description>Contains ready to use extensions for data management in HotChocolate. This includes filtering, projections and sorting</Description>
-    <NoWarn>HC8001;$(NoWarn)</NoWarn>
+    <NoWarn>HC8001;GD0001;$(NoWarn)</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>