decouple mod metadata resolution from main SMAPI logic (#285)

This makes the logic more self-contained for eventual unit testing, and makes failed mods available during dependency resolution so we can make errors more relevant.

1 files changed, 34 insertions, 0 deletions

diff --git a/src/StardewModdingAPI/Framework/ModLoading/ModMetadata.cs b/src/StardewModdingAPI/Framework/ModLoading/ModMetadata.cs
index 1ac167dc..72c4692b 100644
--- a/src/StardewModdingAPI/Framework/ModLoading/ModMetadata.cs
+++ b/src/StardewModdingAPI/Framework/ModLoading/ModMetadata.cs
@@ -20,6 +20,12 @@ namespace StardewModdingAPI.Framework.ModLoading
         /// <summary>Optional metadata about a mod version that SMAPI should assume is compatible or broken, regardless of whether it detects incompatible code.</summary>
         public ModCompatibility Compatibility { get; }
 
+        /// <summary>The metadata resolution status.</summary>
+        public ModMetadataStatus Status { get; set; }
+
+        /// <summary>The reason the metadata is invalid, if any.</summary>
+        public string Error { get; set; }
+
 
         /*********
         ** Public methods
@@ -30,11 +36,39 @@ namespace StardewModdingAPI.Framework.ModLoading
         /// <param name="manifest">The mod manifest.</param>
         /// <param name="compatibility">Optional metadata about a mod version that SMAPI should assume is compatible or broken, regardless of whether it detects incompatible code.</param>
         public ModMetadata(string displayName, string directoryPath, IManifest manifest, ModCompatibility compatibility)
+            : this(displayName, directoryPath, manifest, compatibility, ModMetadataStatus.Found, null)
+        {
+            this.DisplayName = displayName;
+            this.DirectoryPath = directoryPath;
+            this.Manifest = manifest;
+            this.Compatibility = compatibility;
+        }
+
+        /// <summary>Construct an instance.</summary>
+        /// <param name="displayName">The mod's display name.</param>
+        /// <param name="directoryPath">The mod's full directory path.</param>
+        /// <param name="manifest">The mod manifest.</param>
+        /// <param name="compatibility">Optional metadata about a mod version that SMAPI should assume is compatible or broken, regardless of whether it detects incompatible code.</param>
+        /// <param name="status">The metadata resolution status.</param>
+        /// <param name="error">The reason the metadata is invalid, if any.</param>
+        public ModMetadata(string displayName, string directoryPath, IManifest manifest, ModCompatibility compatibility, ModMetadataStatus status, string error)
         {
             this.DisplayName = displayName;
             this.DirectoryPath = directoryPath;
             this.Manifest = manifest;
             this.Compatibility = compatibility;
+            this.Status = status;
+            this.Error = error;
         }
     }
+
+    /// <summary>Indicates the status of a mod's metadata resolution.</summary>
+    internal enum ModMetadataStatus
+    {
+        /// <summary>The mod has been found, but hasn't been processed yet.</summary>
+        Found,
+
+        /// <summary>The mod cannot be loaded.</summary>
+        Failed
+    }
 }