Don't use readonly SpinLock. Fixes #63 #64

src/ImageSharp.Web/Caching/AsyncKeyLock.cs

@@ -27,7 +27,7 @@ internal sealed class AsyncKeyLock
         /// <summary>
         /// SpinLock used to protect access to the Keys and Pool collections.
         /// </summary>
-        private static readonly SpinLock SpinLock = new SpinLock(false);
+        private static SpinLock spinLock = new SpinLock(false);
 
         /// <summary>
         /// Maximum size of the doorman pool. If the pool is already full when releasing
@@ -76,7 +76,7 @@ private static Doorman GetDoorman(string key)
             bool lockTaken = false;
             try
             {
-                SpinLock.Enter(ref lockTaken);
+                spinLock.Enter(ref lockTaken);
 
                 if (!Keys.TryGetValue(key, out doorman))
                 {
@@ -91,7 +91,7 @@ private static Doorman GetDoorman(string key)
             {
                 if (lockTaken)
                 {
-                    SpinLock.Exit();
+                    spinLock.Exit();
                 }
             }
 
@@ -109,7 +109,7 @@ private static void ReleaseDoorman(Doorman doorman)
             bool lockTaken = false;
             try
             {
-                SpinLock.Enter(ref lockTaken);
+                spinLock.Enter(ref lockTaken);
 
                 if (--doorman.RefCount == 0)
                 {
@@ -125,7 +125,7 @@ private static void ReleaseDoorman(Doorman doorman)
             {
                 if (lockTaken)
                 {
-                    SpinLock.Exit();
+                    spinLock.Exit();
                 }
             }
         }

tests/ImageSharp.Web.Tests/Caching/AsyncKeyLockTests.cs

@@ -5,7 +5,6 @@
 
 namespace SixLabors.ImageSharp.Web.Tests.Caching
 {
-    [Collection(nameof(NonParallelFixture))]
     public class AsyncKeyLockTests
     {
         private static readonly AsyncKeyLock AsyncLock = new AsyncKeyLock();
@@ -14,14 +13,7 @@ public class AsyncKeyLockTests
         private const string AsyncKey2 = "ASYNC_KEY2";
 
         [Fact]
-        public void AsyncLockActsAsDoorman()
-        {
-            // Run the two tests from a single test to see if we can stop tests freezing on Travis.
-            this.AsyncLockCanLockByKey();
-            this.AsyncLockAllowsDifferentKeysToRun();
-        }
-
-        private void AsyncLockCanLockByKey()
+        public async Task AsyncLockCanLockByKey()
         {
             bool zeroEntered = false;
             bool entered = false;
@@ -46,11 +38,12 @@ private void AsyncLockCanLockByKey()
                 }
             })).ToArray();
 
-            Task.WaitAll(tasks);
+            await Task.WhenAll(tasks);
             Assert.Equal(5, index);
         }
 
-        private void AsyncLockAllowsDifferentKeysToRun()
+        [Fact]
+        public async Task AsyncLockAllowsDifferentKeysToRun()
         {
             bool zeroEntered = false;
             bool entered = false;
@@ -76,7 +69,7 @@ private void AsyncLockAllowsDifferentKeysToRun()
 
             })).ToArray();
 
-            Task.WaitAll(tasks);
+            await Task.WhenAll(tasks);
             Assert.Equal(5, index);
         }
     }