test: add tests for PropCache

UnitTests~/PropCacheTest.meta

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+fileFormatVersion: 2
+guid: 77aba4362cec4cea91ee64c6e640b6b2
+timeCreated: 1726436552

UnitTests~/PropCacheTest/PropCacheTest.cs

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+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using nadena.dev.modular_avatar.core.editor;
+using nadena.dev.ndmf.preview;
+using NUnit.Framework;
+using UnityEngine;
+using UnityEngine.TestTools;
+
+namespace UnitTests.PropCacheTest
+{
+    public class PropCacheTest
+    {
+        [UnityTest]
+        public IEnumerator TestCacheInvalidation()
+        {
+            int seq = 0;
+
+            Dictionary<int, List<WeakReference<ComputeContext>>> invalidators = new();
+            PropCache<int,int> cache = new PropCache<int, int>((ctx, k) =>
+            {
+                Debug.Log("Generating value for " + k);
+                if (!invalidators.TryGetValue(k, out var list))
+                {
+                    list = new List<WeakReference<ComputeContext>>();
+                    invalidators[k] = list;
+                }
+                
+                list.Add(new WeakReference<ComputeContext>(ctx));
+                
+                return (k * 10) + seq++;
+            });
+            
+            ComputeContext ctx = new ComputeContext("c1");
+            int val = cache.Get(ctx, 1);
+            Assert.AreEqual(10, val);
+            
+            ComputeContext ctx2 = new ComputeContext("c2");
+            val = cache.Get(ctx2, 1);
+            Assert.AreEqual(10, val);
+
+            invalidators[1][0].TryGetTarget(out var target);
+            target?.Invalidate();
+
+            Debug.Log("Pre-flush");
+            ComputeContext.FlushInvalidates();
+            Debug.Log("Mid-flush");
+            ComputeContext.FlushInvalidates();
+            Debug.Log("Post-flush");
+
+            // Task processing can happen asynchronously.
+
+            int limit = 10;
+            while (limit-- > 0 && (!ctx.IsInvalidated || !ctx2.IsInvalidated))
+            {
+                Debug.Log("Waiting for invalidation: " + limit);
+                Thread.Sleep(100);
+            }
+            
+            Assert.IsTrue(ctx.IsInvalidated);
+            Assert.IsTrue(ctx2.IsInvalidated);
+            
+            val = cache.Get(ctx, 1);
+            Assert.AreEqual(12, val);
+
+            yield return null;
+        }
+    }
+}

UnitTests~/PropCacheTest/PropCacheTest.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 6891e8d136c942878bca9b50b5c58ec9
+timeCreated: 1726436558