Use the correct Assert.Single overload (dotnet#2637)

Author: MihaZupan

test/ReverseProxy.Tests/Configuration/ConfigProvider/ConfigurationConfigProviderTests.cs

@@ -523,7 +523,7 @@ private void VerifyValidAbstractConfig(IProxyConfig validConfig, IProxyConfig ab
         Assert.Equal(2, abstractConfig.Clusters.Count);
 
         var cluster1 = validConfig.Clusters.First(c => c.ClusterId == "cluster1");
-        Assert.Single(abstractConfig.Clusters.Where(c => c.ClusterId == "cluster1"));
+        Assert.Single(abstractConfig.Clusters, c => c.ClusterId == "cluster1");
         var abstractCluster1 = abstractConfig.Clusters.Single(c => c.ClusterId == "cluster1");
         Assert.Equal(cluster1.Destinations["destinationA"].Address, abstractCluster1.Destinations["destinationA"].Address);
         Assert.Equal(cluster1.Destinations["destinationA"].Health, abstractCluster1.Destinations["destinationA"].Health);
@@ -569,7 +569,7 @@ private void VerifyValidAbstractConfig(IProxyConfig validConfig, IProxyConfig ab
         Assert.Equal(cluster1.Metadata, abstractCluster1.Metadata);
 
         var cluster2 = validConfig.Clusters.First(c => c.ClusterId == "cluster2");
-        Assert.Single(abstractConfig.Clusters.Where(c => c.ClusterId == "cluster2"));
+        Assert.Single(abstractConfig.Clusters, c => c.ClusterId == "cluster2");
         var abstractCluster2 = abstractConfig.Clusters.Single(c => c.ClusterId == "cluster2");
         Assert.Equal(cluster2.Destinations["destinationC"].Address, abstractCluster2.Destinations["destinationC"].Address);
         Assert.Equal(cluster2.Destinations["destinationC"].Metadata, abstractCluster2.Destinations["destinationC"].Metadata);
@@ -588,7 +588,7 @@ private void VerifyValidAbstractConfig(IProxyConfig validConfig, IProxyConfig ab
     private void VerifyRoute(IProxyConfig validConfig, IProxyConfig abstractConfig, string routeId)
     {
         var route = validConfig.Routes.Single(c => c.RouteId == routeId);
-        Assert.Single(abstractConfig.Routes.Where(c => c.RouteId == routeId));
+        Assert.Single(abstractConfig.Routes, r => r.RouteId == routeId);
         var abstractRoute = abstractConfig.Routes.Single(c => c.RouteId == routeId);
         Assert.Equal(route.ClusterId, abstractRoute.ClusterId);
         Assert.Equal(route.Order, abstractRoute.Order);

test/ReverseProxy.Tests/Management/ProxyConfigManagerTests.cs

@@ -1200,7 +1200,7 @@ public async Task LoadAsync_ConfigFilterConfiguresCluster_Works()
         Assert.NotNull(dataSource);
         Assert.Equal(2, dataSource.Endpoints.Count);
 
-        var endpoint1 = Assert.Single(dataSource.Endpoints.Where(x => x.DisplayName == "route1"));
+        var endpoint1 = Assert.Single(dataSource.Endpoints, e => e.DisplayName == "route1");
         var routeConfig1 = endpoint1.Metadata.GetMetadata<RouteModel>();
         Assert.Equal(47, routeConfig1.Config.Order);
         var clusterState1 = routeConfig1.Cluster;
@@ -1210,7 +1210,7 @@ public async Task LoadAsync_ConfigFilterConfiguresCluster_Works()
         var destination = Assert.Single(clusterState1.DestinationsState.AllDestinations);
         Assert.Equal("http://localhost", destination.Model.Config.Address);
 
-        var endpoint2 = Assert.Single(dataSource.Endpoints.Where(x => x.DisplayName == "route2"));
+        var endpoint2 = Assert.Single(dataSource.Endpoints, e => e.DisplayName == "route2");
         var routeConfig2 = endpoint2.Metadata.GetMetadata<RouteModel>();
         Assert.Equal(12, routeConfig2.Config.Order);
     }

test/ReverseProxy.Tests/Transforms/RequestHeadersTransformExtensionsTests.cs

@@ -135,7 +135,7 @@ public void AddRequestHeadersAllowed()
 
     private static void ValidateRequestHeader(bool append, TransformBuilderContext builderContext)
     {
-        var requestHeaderValueTransform = Assert.Single(builderContext.RequestTransforms.OfType<RequestHeaderValueTransform>().Where(x => x.HeaderName == "name"));
+        var requestHeaderValueTransform = Assert.Single(builderContext.RequestTransforms.OfType<RequestHeaderValueTransform>(), t => t.HeaderName == "name");
         Assert.Equal("value", requestHeaderValueTransform.Value);
         Assert.Equal(append, requestHeaderValueTransform.Append);
     }