add warning in developer mode for mods with no update keys

4 files changed, 21 insertions, 0 deletions

diff --git a/docs/release-notes.md b/docs/release-notes.md
index e524ea65..cde7847e 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -10,6 +10,7 @@
 
 * For modders:
   * Added code analysis to mod build config package to flag common issues as warnings.
+  * Added warning when a mod doesn't have update keys (currently only shown in developer mode).
   * Dropped some deprecated APIs.
   * Fixed assets loaded by temporary content managers not being editable.
   * Fixed issue where assets didn't reload correctly when the player switches language.
diff --git a/src/SMAPI/Framework/IModMetadata.cs b/src/SMAPI/Framework/IModMetadata.cs
index d1e8eb7d..248809df 100644
--- a/src/SMAPI/Framework/IModMetadata.cs
+++ b/src/SMAPI/Framework/IModMetadata.cs
@@ -64,5 +64,8 @@ namespace StardewModdingAPI.Framework
         /// <summary>Set the mod-provided API instance.</summary>
         /// <param name="api">The mod-provided API.</param>
         IModMetadata SetApi(object api);
+
+        /// <summary>Whether the mod has at least one update key set.</summary>
+        bool HasUpdateKeys();
     }
 }
diff --git a/src/SMAPI/Framework/ModLoading/ModMetadata.cs b/src/SMAPI/Framework/ModLoading/ModMetadata.cs
index 1a0f9994..af888b71 100644
--- a/src/SMAPI/Framework/ModLoading/ModMetadata.cs
+++ b/src/SMAPI/Framework/ModLoading/ModMetadata.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using StardewModdingAPI.Framework.ModData;
 
 namespace StardewModdingAPI.Framework.ModLoading
@@ -102,5 +103,13 @@ namespace StardewModdingAPI.Framework.ModLoading
             this.Api = api;
             return this;
         }
+
+        /// <summary>Whether the mod has at least one update key set.</summary>
+        public bool HasUpdateKeys()
+        {
+            return
+                this.Manifest?.UpdateKeys != null
+                && this.Manifest.UpdateKeys.Any(key => !string.IsNullOrWhiteSpace(key));
+        }
     }
 }
diff --git a/src/SMAPI/Program.cs b/src/SMAPI/Program.cs
index f70efb89..cf1c082a 100644
--- a/src/SMAPI/Program.cs
+++ b/src/SMAPI/Program.cs
@@ -722,6 +722,10 @@ namespace StardewModdingAPI
                     continue;
                 }
 
+                // show warnings
+                if (this.Settings.DeveloperMode && !metadata.HasUpdateKeys())
+                    this.Monitor.Log($"      {metadata.DisplayName} has no {nameof(IManifest.UpdateKeys)} in its manifest. You may not see update alerts for this mod.", LogLevel.Warn);
+
                 // load mod as content pack
                 IMonitor monitor = this.GetSecondaryMonitor(metadata.DisplayName);
                 ContentManagerShim contentManager = this.ContentCore.CreateContentManager($"Mods.{metadata.Manifest.UniqueID}", metadata.DirectoryPath);
@@ -766,6 +770,10 @@ namespace StardewModdingAPI
                         continue;
                     }
 
+                    // show warnings
+                    if (this.Settings.DeveloperMode && !metadata.HasUpdateKeys() && metadata.Manifest.UniqueID != "SMAPI.ConsoleCommands")
+                        this.Monitor.Log($"      {metadata.DisplayName} has no {nameof(IManifest.UpdateKeys)} in its manifest. You may not see update alerts for this mod.", LogLevel.Warn);
+
                     // load mod
                     string assemblyPath = metadata.Manifest?.EntryDll != null
                         ? Path.Combine(metadata.DirectoryPath, metadata.Manifest.EntryDll)