subclass chatbox to log game errors

docs/release-notes.md

@@ -11,6 +11,7 @@
 * For modders:
   * Expanded `PerScreen<T>` API: you can now get/set the value for any screen, get all active values, or clear all values.
   * Expanded player info received from multiplayer API/events with new `IsSplitScreen` and `ScreenID` fields.
+  * Game errors shown in the chatbox are now logged.
   * Added an option to disable rewriting mods for compatibility (thanks to Bpendragon!). This may prevent older mods from loading, but bypasses a Visual Studio crash when debugging.
 
 * For the Error Handler mod:

src/SMAPI/Framework/SChatBox.cs

@@ -0,0 +1,49 @@
+using StardewValley;
+using StardewValley.Menus;
+
+namespace StardewModdingAPI.Framework
+{
+    /// <summary>SMAPI's implementation of the chatbox which intercepts errors for logging.</summary>
+    internal class SChatBox : ChatBox
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>Encapsulates monitoring and logging.</summary>
+        private readonly IMonitor Monitor;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="monitor">Encapsulates monitoring and logging.</param>
+        public SChatBox(IMonitor monitor)
+        {
+            this.Monitor = monitor;
+        }
+
+        /// <inheritdoc />
+        protected override void runCommand(string command)
+        {
+            this.Monitor.Log($"> chat command: {command}");
+            base.runCommand(command);
+        }
+
+        /// <inheritdoc />
+        public override void receiveChatMessage(long sourceFarmer, int chatKind, LocalizedContentManager.LanguageCode language, string message)
+        {
+            if (chatKind == ChatBox.errorMessage)
+            {
+                // log error
+                this.Monitor.Log(message, LogLevel.Error);
+
+                // add event details if applicable
+                if (Game1.CurrentEvent != null && message.StartsWith("Event script error:"))
+                    this.Monitor.Log($"In event #{Game1.CurrentEvent.id} for location {Game1.currentLocation?.NameOrUniqueName}", LogLevel.Error);
+            }
+
+            base.receiveChatMessage(sourceFarmer, chatKind, language, message);
+        }
+    }
+}

src/SMAPI/Framework/SCore.cs

@@ -1054,6 +1054,13 @@ namespace StardewModdingAPI.Framework
                 this.OnReturnedToTitle();
             }
 
+            // override chatbox
+            if (newStage == LoadStage.Loaded)
+            {
+                Game1.onScreenMenus.Remove(Game1.chatBox);
+                Game1.onScreenMenus.Add(Game1.chatBox = new SChatBox(this.LogManager.MonitorForGame));
+            }
+
             // raise events
             this.EventManager.LoadStageChanged.Raise(new LoadStageChangedEventArgs(oldStage, newStage));
             if (newStage == LoadStage.None)