Apply new suggestions from Resharper EAP

Author: bkoelman

src/JsonApiDotNetCore/Configuration/ResourceDescriptorAssemblyCache.cs

@@ -12,10 +12,7 @@ internal sealed class ResourceDescriptorAssemblyCache
 
     public void RegisterAssembly(Assembly assembly)
     {
-        if (!_resourceDescriptorsPerAssembly.ContainsKey(assembly))
-        {
-            _resourceDescriptorsPerAssembly[assembly] = null;
-        }
+        _resourceDescriptorsPerAssembly.TryAdd(assembly, null);
     }
 
     public IReadOnlyCollection<ResourceDescriptor> GetResourceDescriptors()

src/JsonApiDotNetCore/Middleware/JsonApiRoutingConvention.cs

@@ -101,10 +101,10 @@ public void Apply(ApplicationModel application)
                             $"resource type '{resourceClrType}', which does not exist in the resource graph.");
                     }
 
-                    if (_controllerPerResourceTypeMap.ContainsKey(resourceType))
+                    if (_controllerPerResourceTypeMap.TryGetValue(resourceType, out ControllerModel? existingModel))
                     {
                         throw new InvalidConfigurationException(
-                            $"Multiple controllers found for resource type '{resourceType}': '{_controllerPerResourceTypeMap[resourceType].ControllerType}' and '{controller.ControllerType}'.");
+                            $"Multiple controllers found for resource type '{resourceType}': '{existingModel.ControllerType}' and '{controller.ControllerType}'.");
                     }
 
                     _resourceTypePerControllerTypeMap.Add(controller.ControllerType, resourceType);
@@ -119,10 +119,10 @@ public void Apply(ApplicationModel application)
 
             string template = TemplateFromResource(controller) ?? TemplateFromController(controller);
 
-            if (_registeredControllerNameByTemplate.ContainsKey(template))
+            if (_registeredControllerNameByTemplate.TryGetValue(template, out string? controllerName))
             {
                 throw new InvalidConfigurationException(
-                    $"Cannot register '{controller.ControllerType.FullName}' for template '{template}' because '{_registeredControllerNameByTemplate[template]}' was already registered for this template.");
+                    $"Cannot register '{controller.ControllerType.FullName}' for template '{template}' because '{controllerName}' was already registered for this template.");
             }
 
             _registeredControllerNameByTemplate.Add(template, controller.ControllerType.FullName!);

src/JsonApiDotNetCore/Queries/Internal/QueryableBuilding/SelectClauseBuilder.cs

@@ -185,10 +185,7 @@ private static void IncludeEagerLoads(ResourceType resourceType, Dictionary<Prop
 
             // When an entity navigation property is decorated with both EagerLoadAttribute and RelationshipAttribute,
             // it may already exist with a sub-layer. So do not overwrite in that case.
-            if (!propertySelectors.ContainsKey(propertySelector.Property))
-            {
-                propertySelectors[propertySelector.Property] = propertySelector;
-            }
+            propertySelectors.TryAdd(propertySelector.Property, propertySelector);
         }
     }