update MemoryCache hack extension to support the new implementation

RPCS3 · Oct 15, 2024 · 2d47dcc · 2d47dcc
1 parent bc07b77
commit 2d47dcc
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Showing 2 changed files with 29 additions and 8 deletions.
diff --git a/CompatBot/Utils/Extensions/MemoryCacheExtensions.cs b/CompatBot/Utils/Extensions/MemoryCacheExtensions.cs
@@ -8,29 +8,43 @@ namespace CompatBot.Utils;
 
 internal static class MemoryCacheExtensions
 {
+    private static readonly object throaway = new object();
+
     public static List<T> GetCacheKeys<T>(this MemoryCache memoryCache)
     {
+        // idk why it requires access before it populates the internal state
+        memoryCache.TryGetValue("str", out _);
+        memoryCache.TryGetValue(throaway, out _);
+
+        // get the internal state object
         var stateField = memoryCache.GetType()
             .GetFields(BindingFlags.NonPublic | BindingFlags.Instance)
             .FirstOrDefault(fi => fi.Name == "_coherentState");
         var coherentState = stateField?.GetValue(memoryCache);
         if (coherentState is null)
         {
             Config.Log.Error($"Looks like {nameof(MemoryCache)} internals have changed");
-            return new();
+            return [];
         }
 
-        var field = coherentState.GetType()
+        // get the actual underlying key-value object
+        var stringField = coherentState.GetType()
             .GetFields(BindingFlags.NonPublic | BindingFlags.Instance)
-            .FirstOrDefault(fi => fi.Name == "_entries");
-        if (field is null)
+            .FirstOrDefault(fi => fi.Name == "_stringEntries");
+        var nonStringField = coherentState.GetType()
+            .GetFields(BindingFlags.NonPublic | BindingFlags.Instance)
+            .FirstOrDefault(fi => fi.Name == "_nonStringEntries");
+        if (stringField is null || nonStringField is null)
         {
             Config.Log.Error($"Looks like {nameof(MemoryCache)} internals have changed");
-            return new();
+            return [];
         }
 
-        var value = (IDictionary?)field.GetValue(coherentState);
-        return value?.Keys.OfType<T>().ToList() ?? new List<T>();
+        // read the keys
+        var value = typeof(T) == typeof(string)
+            ? (IDictionary?)stringField.GetValue(coherentState)
+            : (IDictionary?)nonStringField.GetValue(coherentState);
+        return value?.Keys.OfType<T>().ToList() ?? [];
     }
 
     public static Dictionary<TKey, ICacheEntry?> GetCacheEntries<TKey>(this MemoryCache memoryCache)

diff --git a/Tests/MemoryCacheExtensionTests.cs b/Tests/MemoryCacheExtensionTests.cs
@@ -14,7 +14,14 @@ public void GetCacheKeysTest()
         var cache = new MemoryCache(new MemoryCacheOptions { ExpirationScanFrequency = TimeSpan.FromHours(1) });
         Assert.That(cache.GetCacheKeys<int>(), Is.Empty);
 
-        cache.Set(13, "val13");
+        const string testVal = "vale13";
+        cache.Set(13, testVal);
+        Assert.Multiple(() =>
+            {
+                Assert.That(cache.TryGetValue(13, out string expectedVal), Is.True);
+                Assert.That(expectedVal, Is.EqualTo(testVal));
+            }
+        );
         Assert.That(cache.GetCacheKeys<int>(), Has.Count.EqualTo(1));
     }