4 files changed, 22 insertions, 3 deletions
diff --git a/src/StardewModdingAPI/Advanced/ConfigFile.cs b/src/StardewModdingAPI/Advanced/ConfigFile.cs
index 1a2e6618..78cad26a 100644
--- a/src/StardewModdingAPI/Advanced/ConfigFile.cs
+++ b/src/StardewModdingAPI/Advanced/ConfigFile.cs
@@ -1,9 +1,11 @@
-using System.IO;
+using System;
+using System.IO;
 using Newtonsoft.Json;
 
 namespace StardewModdingAPI.Advanced
 {
     /// <summary>Wraps a configuration file with IO methods for convenience.</summary>
+    [Obsolete]
     public abstract class ConfigFile : IConfigFile
     {
         /*********
diff --git a/src/StardewModdingAPI/Advanced/IConfigFile.cs b/src/StardewModdingAPI/Advanced/IConfigFile.cs
index 5bc31a88..1b424ace 100644
--- a/src/StardewModdingAPI/Advanced/IConfigFile.cs
+++ b/src/StardewModdingAPI/Advanced/IConfigFile.cs
@@ -1,6 +1,9 @@
-namespace StardewModdingAPI.Advanced
+using System;
+
+namespace StardewModdingAPI.Advanced
 {
     /// <summary>Wraps a configuration file with IO methods for convenience.</summary>
+    [Obsolete]
     public interface IConfigFile
     {
         /*********
diff --git a/src/StardewModdingAPI/Framework/ModHelper.cs b/src/StardewModdingAPI/Framework/ModHelper.cs
index 04767de5..0d50201b 100644
--- a/src/StardewModdingAPI/Framework/ModHelper.cs
+++ b/src/StardewModdingAPI/Framework/ModHelper.cs
@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using StardewModdingAPI.Advanced;
 using StardewModdingAPI.Framework.Reflection;
 using StardewModdingAPI.Framework.Serialisation;
 
@@ -14,6 +15,9 @@ namespace StardewModdingAPI.Framework
         /// <summary>Encapsulates SMAPI's JSON file parsing.</summary>
         private readonly JsonHelper JsonHelper;
 
+        /// <summary>Manages deprecation warnings.</summary>
+        private static DeprecationManager DeprecationManager;
+
 
         /*********
         ** Accessors
@@ -61,6 +65,13 @@ namespace StardewModdingAPI.Framework
             this.ConsoleCommands = new CommandHelper(modName, commandManager);
         }
 
+        /// <summary>Injects types required for backwards compatibility.</summary>
+        /// <param name="deprecationManager">Manages deprecation warnings.</param>
+        internal static void Shim(DeprecationManager deprecationManager)
+        {
+            ModHelper.DeprecationManager = deprecationManager;
+        }
+
         /****
         ** Mod config file
         ****/
@@ -69,7 +80,9 @@ namespace StardewModdingAPI.Framework
         public TConfig ReadConfig<TConfig>()
             where TConfig : class, new()
         {
-            var config = this.ReadJsonFile<TConfig>("config.json") ?? new TConfig();
+            TConfig config = this.ReadJsonFile<TConfig>("config.json") ?? new TConfig();
+            if (config is IConfigFile)
+                ModHelper.DeprecationManager.Warn($"{nameof(IConfigFile)}", "1.9", DeprecationLevel.Info);
             this.WriteConfig(config); // create file or fill in missing fields
             return config;
         }
diff --git a/src/StardewModdingAPI/Program.cs b/src/StardewModdingAPI/Program.cs
index 360f75f0..6ebeccd2 100644
--- a/src/StardewModdingAPI/Program.cs
+++ b/src/StardewModdingAPI/Program.cs
@@ -98,6 +98,7 @@ namespace StardewModdingAPI
             InternalExtensions.Shim(this.ModRegistry);
             Log.Shim(this.DeprecationManager, this.GetSecondaryMonitor("legacy mod"), this.ModRegistry);
             Mod.Shim(this.DeprecationManager);
+            ModHelper.Shim(this.DeprecationManager);
             ContentEvents.Shim(this.ModRegistry, this.Monitor);
             PlayerEvents.Shim(this.DeprecationManager);
             TimeEvents.Shim(this.DeprecationManager);