Got at least one data fetching method working; turns out, we can't use a patched LogicStack to get the data

Vendor/Swan.Lite-3.1.0/Extensions.Functional.cs

@@ -0,0 +1,179 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Swan
+{
+    /// <summary>
+    /// Functional programming extension methods.
+    /// </summary>
+    public static class FunctionalExtensions
+    {
+        /// <summary>
+        /// Whens the specified condition.
+        /// </summary>
+        /// <typeparam name="T">The type of IQueryable.</typeparam>
+        /// <param name="list">The list.</param>
+        /// <param name="condition">The condition.</param>
+        /// <param name="fn">The function.</param>
+        /// <returns>
+        /// The IQueryable.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">
+        /// this
+        /// or
+        /// condition
+        /// or
+        /// fn.
+        /// </exception>
+        public static IQueryable<T> When<T>(
+            this IQueryable<T> list,
+            Func<bool> condition,
+            Func<IQueryable<T>, IQueryable<T>> fn)
+        {
+            if (list == null)
+                throw new ArgumentNullException(nameof(list));
+
+            if (condition == null)
+                throw new ArgumentNullException(nameof(condition));
+
+            if (fn == null)
+                throw new ArgumentNullException(nameof(fn));
+
+            return condition() ? fn(list) : list;
+        }
+
+        /// <summary>
+        /// Whens the specified condition.
+        /// </summary>
+        /// <typeparam name="T">The type of IEnumerable.</typeparam>
+        /// <param name="list">The list.</param>
+        /// <param name="condition">The condition.</param>
+        /// <param name="fn">The function.</param>
+        /// <returns>
+        /// The IEnumerable.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">
+        /// this
+        /// or
+        /// condition
+        /// or
+        /// fn.
+        /// </exception>
+        public static IEnumerable<T> When<T>(
+            this IEnumerable<T> list,
+            Func<bool> condition,
+            Func<IEnumerable<T>, IEnumerable<T>> fn)
+        {
+            if (list == null)
+                throw new ArgumentNullException(nameof(list));
+
+            if (condition == null)
+                throw new ArgumentNullException(nameof(condition));
+
+            if (fn == null)
+                throw new ArgumentNullException(nameof(fn));
+
+            return condition() ? fn(list) : list;
+        }
+
+        /// <summary>
+        /// Adds the value when the condition is true.
+        /// </summary>
+        /// <typeparam name="T">The type of IList element.</typeparam>
+        /// <param name="list">The list.</param>
+        /// <param name="condition">The condition.</param>
+        /// <param name="value">The value.</param>
+        /// <returns>
+        /// The IList.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">
+        /// this
+        /// or
+        /// condition
+        /// or
+        /// value.
+        /// </exception>
+        public static IList<T> AddWhen<T>(
+            this IList<T> list,
+            Func<bool> condition,
+            Func<T> value)
+        {
+            if (list == null)
+                throw new ArgumentNullException(nameof(list));
+
+            if (condition == null)
+                throw new ArgumentNullException(nameof(condition));
+
+            if (value == null)
+                throw new ArgumentNullException(nameof(value));
+
+            if (condition())
+                list.Add(value());
+
+            return list;
+        }
+
+        /// <summary>
+        /// Adds the value when the condition is true.
+        /// </summary>
+        /// <typeparam name="T">The type of IList element.</typeparam>
+        /// <param name="list">The list.</param>
+        /// <param name="condition">if set to <c>true</c> [condition].</param>
+        /// <param name="value">The value.</param>
+        /// <returns>
+        /// The IList.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">list.</exception>
+        public static IList<T> AddWhen<T>(
+            this IList<T> list,
+            bool condition,
+            T value)
+        {
+            if (list == null)
+                throw new ArgumentNullException(nameof(list));
+
+            if (condition)
+                list.Add(value);
+
+            return list;
+        }
+
+        /// <summary>
+        /// Adds the range when the condition is true.
+        /// </summary>
+        /// <typeparam name="T">The type of List element.</typeparam>
+        /// <param name="list">The list.</param>
+        /// <param name="condition">The condition.</param>
+        /// <param name="value">The value.</param>
+        /// <returns>
+        /// The List.
+        /// </returns>
+        /// <exception cref="ArgumentNullException">
+        /// this
+        /// or
+        /// condition
+        /// or
+        /// value.
+        /// </exception>
+        public static List<T> AddRangeWhen<T>(
+            this List<T> list,
+            Func<bool> condition,
+            Func<IEnumerable<T>> value)
+        {
+            if (list == null)
+                throw new ArgumentNullException(nameof(list));
+
+            if (condition == null)
+                throw new ArgumentNullException(nameof(condition));
+
+            if (value == null)
+                throw new ArgumentNullException(nameof(value));
+
+            if (condition())
+                list.AddRange(value());
+
+            return list;
+        }
+    }
+}