update component limits + add ComponentCount() extension (#3107)

Author: Misha-133

src/Discord.Net.Core/Entities/Interactions/MessageComponents/Builders/ComponentBuilderV2.cs

@@ -7,9 +7,9 @@ namespace Discord;
 public class ComponentBuilderV2 : IStaticComponentContainer
 {
     /// <summary>
-    ///    Gets the maximum number of components that can be added to this container.
+    ///    Gets the maximum number of components that can be added to a message.
     /// </summary>
-    public const int MaxComponents = 10;
+    public const int MaxComponents = 40;
 
     private List<IMessageComponentBuilder> _components = new();
 
@@ -53,8 +53,8 @@ public ComponentBuilderV2 WithComponents(IEnumerable<IMessageComponentBuilder> c
     /// <inheritdoc cref="IMessageComponentBuilder.Build" />
     public MessageComponent Build()
     {
-        if (_components.Count is 0 or >MaxComponents)
-            throw new InvalidOperationException($"The number of components must be between 1 and {MaxComponents}.");
+        Preconditions.AtLeast(Components?.Count ?? 0, 1, nameof(Components.Count), "At least 1 component must be added to this container.");
+        Preconditions.AtMost(this.ComponentCount(), MaxComponents, nameof(Components.Count), $"A message must contain {MaxComponents} components or less.");
 
         if (_components.Any(x => 
                 x is not ActionRowBuilder

src/Discord.Net.Core/Entities/Interactions/MessageComponents/Builders/ComponentContainerExtensions.cs

@@ -5,6 +5,15 @@ namespace Discord;
 
 public static class ComponentContainerExtensions
 {
+    /// <summary>
+    ///     Gets the total number of components in this and all child <see cref="IComponentContainer"/>s combined.
+    /// </summary>
+    public static int ComponentCount(this IComponentContainer container)
+        => (container.Components?.Count ?? 0)
+        + container.Components?
+            .OfType<IComponentContainer>()
+            .Sum(x => x.ComponentCount()) ?? 0;
+
     /// <summary>
     ///     Adds a <see cref="TextDisplayBuilder"/> to the container.
     /// </summary>

src/Discord.Net.Core/Entities/Interactions/MessageComponents/Builders/ContainerBuilder.cs

@@ -7,11 +7,6 @@ namespace Discord;
 
 public class ContainerBuilder : IMessageComponentBuilder, IStaticComponentContainer
 {
-    /// <summary>
-    ///     The maximum number of components allowed in a container.
-    /// </summary>
-    public const int MaxComponents = 10;
-
     /// <inheritdoc />
     public ComponentType Type => ComponentType.Container;
 
@@ -86,9 +81,6 @@ public ContainerBuilder WithComponents(IEnumerable<IMessageComponentBuilder> com
     /// <inheritdoc cref="IMessageComponentBuilder.Build"/>
     public ContainerComponent Build()
     {
-        if (_components.Count is 0 or > MaxComponents)
-            throw new InvalidOperationException($"A container must have between 1 and {MaxComponents} components.");
-
         if (_components.Any(x => x
                 is not ActionRowBuilder
                 and not TextDisplayBuilder