Add shuffle filter.

Author: sarahelsaig

Lombiq.HelpfulExtensions/Extensions/Liquid/Readme.md

@@ -12,6 +12,7 @@ Adds various Liquid tags and filters. For more information about Liquid in Orcha
 - `is_not_empty`: Returns `true` if the input is not null and not empty.
 - `shapes_build_display: 'Summary'`: Behaves the same way as the built-in `shape_build_display` filter, except both the input and output are arrays for bulk operation (e.g. from queries).
 - `shapes_render`: Behaves the same way as the built-in `shape_render` filter, except both the input and output are arrays for bulk operation (e.g. from queries).
+- `shuffle`: If the input is an array, it returns a new array where the input's items are sorted in a random order.
 
 ### Array filter example
 

Lombiq.HelpfulExtensions/Extensions/Liquid/Services/ShuffleFilter.cs

@@ -0,0 +1,31 @@
+using Fluid;
+using Fluid.Values;
+using Lombiq.HelpfulLibraries.Common.Utilities;
+using OrchardCore.Liquid;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Lombiq.HelpfulExtensions.Extensions.Liquid.Services;
+
+public class ShuffleFilter : ILiquidFilter
+{
+    public ValueTask<FluidValue> ProcessAsync(
+        FluidValue input,
+        FilterArguments arguments,
+        LiquidTemplateContext context)
+    {
+        if (input is not ArrayValue { Values: { Count: > 0 } values })
+        {
+            return ValueTask.FromResult(input);
+        }
+
+        var random = new NonSecurityRandomizer();
+        var shuffled = values
+            .Select(item => (Item: item, Sort: random.Get()))
+            .OrderBy(pair => pair.Sort)
+            .Select(pair => pair.Item)
+            .ToArray();
+
+        return FluidValue.Create(shuffled, context.Options);
+    }
+}

Lombiq.HelpfulExtensions/Extensions/Liquid/Startup.cs

@@ -15,5 +15,6 @@ public override void ConfigureServices(IServiceCollection services)
         services.AddLiquidParserTag<AssignArrayParserBlock>("assign_array");
         services.AddLiquidFilter<ShapesBuildDisplayFilter>("shapes_build_display");
         services.AddLiquidFilter<ShapesRenderFilter>("shapes_render");
+        services.AddLiquidFilter<ShuffleFilter>("shuffle");
     }
 }