Update ListProxyTest.WeakToWeak so it works in Release mode (#866)

* Update ListProxyTest.WeakToWeak so it works in Release mode

* Disable CS0414 for test

diff --git a/Xamarin.Forms.Core.UnitTests/ListProxyTests.cs b/Xamarin.Forms.Core.UnitTests/ListProxyTests.cs
index 2d9cda4..cd94e71 100644 (file)
--- a/Xamarin.Forms.Core.UnitTests/ListProxyTests.cs
+++ b/Xamarin.Forms.Core.UnitTests/ListProxyTests.cs
@@ -423,29 +423,31 @@ namespace Xamarin.Forms.Core.UnitTests
                        }
                }
 
+               // Need a member to keep this reference around, otherwise it gets optimized
+               // out early in Release mode during the WeakToWeak test
+#pragma warning disable 0414 // Never accessed, it's just here to prevent GC
+               ListProxy _proxyForWeakToWeakTest;
+#pragma warning restore 0414
+
                [Test]
-               [Ignore()]
-               //TODO: Need to figure why this is failing on release 
                public void WeakToWeak()
                {
                        WeakCollectionChangedList list = new WeakCollectionChangedList();
-                       var proxy = new ListProxy(list);
+                       _proxyForWeakToWeakTest = new ListProxy(list);
 
-                       Assert.True(list.AddObject());
+                       Assert.True(list.AddObject(), "GC hasn't run");
 
                        GC.Collect();
                        GC.WaitForPendingFinalizers();
-                       GC.Collect();
 
-                       Assert.IsTrue(list.AddObject());
+                       Assert.IsTrue(list.AddObject(), "GC run, but proxy should still hold a reference");
 
-                       proxy = null;
+                       _proxyForWeakToWeakTest = null;
 
                        GC.Collect();
                        GC.WaitForPendingFinalizers();
-                       GC.Collect();
 
-                       Assert.IsFalse(list.AddObject());
+                       Assert.IsFalse(list.AddObject(), "Proxy is gone and GC has run");
                }
 
                public class WeakCollectionChangedList : List<object>, INotifyCollectionChanged
@@ -467,7 +469,7 @@ namespace Xamarin.Forms.Core.UnitTests
                        {
                                bool invoked = false;
                                var me = new object();
-
+                               Console.WriteLine($"Handler count is {handlers.Count}");
                                foreach (var handler in handlers.ToList())
                                {
                                        if (handler.IsActive)
@@ -477,6 +479,7 @@ namespace Xamarin.Forms.Core.UnitTests
                                        }
                                        else
                                        {
+                                               Console.WriteLine($"Handler is inactive");
                                                handlers.Remove(handler);
                                        }
                                }