add base implementation for mod event classes (#310)

src/SMAPI/Framework/Events/ModEventsBase.cs

@@ -0,0 +1,28 @@
+namespace StardewModdingAPI.Framework.Events
+{
+    /// <summary>An internal base class for event API classes.</summary>
+    internal abstract class ModEventsBase
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The underlying event manager.</summary>
+        protected readonly EventManager EventManager;
+
+        /// <summary>The mod which uses this instance.</summary>
+        protected readonly IModMetadata Mod;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="mod">The mod which uses this instance.</param>
+        /// <param name="eventManager">The underlying event manager.</param>
+        internal ModEventsBase(IModMetadata mod, EventManager eventManager)
+        {
+            this.Mod = mod;
+            this.EventManager = eventManager;
+        }
+    }
+}

src/SMAPI/Framework/Events/ModWorldEvents.cs

@@ -4,18 +4,8 @@ using StardewModdingAPI.Events;
 namespace StardewModdingAPI.Framework.Events
 {
     /// <summary>Events raised when something changes in the world.</summary>
-    public class ModWorldEvents : IWorldEvents
+    internal class ModWorldEvents : ModEventsBase, IWorldEvents
     {
-        /*********
-        ** Properties
-        *********/
-        /// <summary>The underlying event manager.</summary>
-        private readonly EventManager EventManager;
-
-        /// <summary>The mod which uses this instance.</summary>
-        private readonly IModMetadata Mod;
-
-
         /*********
         ** Accessors
         *********/
@@ -69,9 +59,6 @@ namespace StardewModdingAPI.Framework.Events
         /// <param name="mod">The mod which uses this instance.</param>
         /// <param name="eventManager">The underlying event manager.</param>
         internal ModWorldEvents(IModMetadata mod, EventManager eventManager)
-        {
+            : base(mod, eventManager) { }
-            this.Mod = mod;
-            this.EventManager = eventManager;
-        }
     }
 }

src/SMAPI/StardewModdingAPI.csproj

@@ -98,6 +98,7 @@
     <Compile Include="Framework\ContentManagers\GameContentManager.cs" />
     <Compile Include="Framework\ContentManagers\IContentManager.cs" />
     <Compile Include="Framework\ContentManagers\ModContentManager.cs" />
+    <Compile Include="Framework\Events\ModEventsBase.cs" />
     <Compile Include="Framework\Events\EventManager.cs" />
     <Compile Include="Events\IModEvents.cs" />
     <Compile Include="Framework\Events\ManagedEvent.cs" />