Nullable fixes.

backend/src/Squidex.Domain.Apps.Entities/Apps/Indexes/AppsIndex.cs

@@ -80,7 +80,7 @@ namespace Squidex.Domain.Apps.Entities.Apps.Indexes
                     await Task.WhenAll(ids
                         .Select(GetAppAsync));
 
-                return apps.Where(x => x != null).ToList();
+                return apps.NotNull().ToList();
             }
         }
 
@@ -98,7 +98,7 @@ namespace Squidex.Domain.Apps.Entities.Apps.Indexes
                         .SelectMany(x => x).Distinct()
                         .Select(GetAppAsync));
 
-                return apps.Where(x => x != null).ToList();
+                return apps.NotNull().ToList();
             }
         }
 

backend/src/Squidex.Domain.Apps.Entities/Contents/GraphQL/Types/Extensions.cs

@@ -44,7 +44,7 @@ namespace Squidex.Domain.Apps.Entities.Contents.GraphQL.Types
         {
             var contents = await Task.WhenAll(keys.Select(dataLoader.LoadAsync));
 
-            return contents.Where(x => x != null).ToList();
+            return contents.NotNull().ToList();
         }
     }
 }

backend/src/Squidex.Domain.Apps.Entities/Contents/Queries/QueryExecutionContext.cs

@@ -113,7 +113,7 @@ namespace Squidex.Domain.Apps.Entities.Contents.Queries
                 }
             }
 
-            return ids.Select(cachedAssets.GetOrDefault).Where(x => x != null).ToList();
+            return ids.Select(cachedAssets.GetOrDefault).NotNull().ToList();
         }
 
         public virtual async Task<IReadOnlyList<IContentEntity>> GetReferencedContentsAsync(ICollection<Guid> ids)
@@ -132,7 +132,7 @@ namespace Squidex.Domain.Apps.Entities.Contents.Queries
                 }
             }
 
-            return ids.Select(cachedContents.GetOrDefault).Where(x => x != null).ToList();
+            return ids.Select(cachedContents.GetOrDefault).NotNull().ToList();
         }
     }
 }

backend/src/Squidex.Domain.Apps.Entities/Rules/Guards/RuleTriggerValidator.cs

@@ -90,7 +90,7 @@ namespace Squidex.Domain.Apps.Entities.Rules.Guards
 
                 var checkErrors = await Task.WhenAll(tasks);
 
-                errors.AddRange(checkErrors.Where(x => x != null));
+                errors.AddRange(checkErrors.NotNull());
             }
 
             return errors;

backend/src/Squidex.Domain.Apps.Entities/Rules/Indexes/RulesIndex.cs

@@ -43,7 +43,7 @@ namespace Squidex.Domain.Apps.Entities.Rules.Indexes
                     await Task.WhenAll(
                         ids.Select(GetRuleAsync));
 
-                return rules.Where(x => x != null).ToList();
+                return rules.NotNull().ToList();
             }
         }
 

backend/src/Squidex.Domain.Apps.Entities/Schemas/Indexes/SchemasIndex.cs

@@ -44,7 +44,7 @@ namespace Squidex.Domain.Apps.Entities.Schemas.Indexes
                     await Task.WhenAll(
                         ids.Select(id => GetSchemaAsync(appId, id, allowDeleted)));
 
-                return schemas.Where(x => x != null).ToList();
+                return schemas.NotNull().ToList();
             }
         }
 

backend/src/Squidex.Infrastructure.Azure/EventSourcing/CosmosDbSubscription.cs

@@ -56,22 +56,10 @@ namespace Squidex.Infrastructure.EventSourcing
             {
                 try
                 {
-                    Collection CreateCollection(string name)
-                    {
-                        var collection = new Collection();
-
-                        collection.CollectionName = name;
-                        collection.DatabaseName = store.DatabaseId;
-                        collection.MasterKey = store.MasterKey;
-                        collection.Uri = store.ServiceUri;
-
-                        return collection;
-                    }
-
                     var processor =
                         await new Builder()
-                            .WithFeedCollection(CreateCollection(Constants.Collection))
-                            .WithLeaseCollection(CreateCollection(Constants.LeaseCollection))
+                            .WithFeedCollection(CreateCollection(store, Constants.Collection))
+                            .WithLeaseCollection(CreateCollection(store, Constants.LeaseCollection))
                             .WithHostName(hostName)
                             .WithProcessorOptions(new Options { StartFromBeginning = fromBeginning, LeasePrefix = hostName })
                             .WithObserverFactory(this)
@@ -88,6 +76,18 @@ namespace Squidex.Infrastructure.EventSourcing
             });
         }
 
+        private static Collection CreateCollection(CosmosDbEventStore store, string name)
+        {
+            var collection = new Collection();
+
+            collection.CollectionName = name;
+            collection.DatabaseName = store.DatabaseId;
+            collection.MasterKey = store.MasterKey;
+            collection.Uri = store.ServiceUri;
+
+            return collection;
+        }
+
         public IChangeFeedObserver CreateObserver()
         {
             return this;

backend/src/Squidex.Infrastructure/CollectionExtensions.cs

@@ -30,7 +30,7 @@ namespace Squidex.Infrastructure
 
         public static IEnumerable<T> SortList<T, TKey>(this IEnumerable<T> input, Func<T, TKey> idProvider, IReadOnlyList<TKey> ids) where T : class
         {
-            return ids.Select(id => input.FirstOrDefault(x => Equals(idProvider(x), id))).Where(x => x != null);
+            return ids.Select(id => input.FirstOrDefault(x => Equals(idProvider(x), id))).NotNull();
         }
 
         public static IEnumerable<T> Duplicates<T>(this IEnumerable<T> input)
@@ -80,6 +80,11 @@ namespace Squidex.Infrastructure
             return source ?? Enumerable.Empty<T>();
         }
 
+        public static IEnumerable<T> NotNull<T>(this IEnumerable<T?> source) where T : class
+        {
+            return source.Where(x => x != null)!;
+        }
+
         public static IEnumerable<T> Concat<T>(this IEnumerable<T> source, T value)
         {
             return source.Concat(Enumerable.Repeat(value, 1));
@@ -261,7 +266,7 @@ namespace Squidex.Infrastructure
             }
         }
 
-        public sealed class KeyValuePairComparer<TKey, TValue> : IEqualityComparer<KeyValuePair<TKey, TValue>>
+        public sealed class KeyValuePairComparer<TKey, TValue> : IEqualityComparer<KeyValuePair<TKey, TValue>> where TKey : notnull
         {
             private readonly IEqualityComparer<TKey> keyComparer;
             private readonly IEqualityComparer<TValue> valueComparer;
@@ -279,7 +284,17 @@ namespace Squidex.Infrastructure
 
             public int GetHashCode(KeyValuePair<TKey, TValue> obj)
             {
-                return keyComparer.GetHashCode(obj.Key) ^ valueComparer.GetHashCode(obj.Value);
+                return keyComparer.GetHashCode(obj.Key) ^ ValueHashCode(obj);
+            }
+
+            private int ValueHashCode(KeyValuePair<TKey, TValue> obj)
+            {
+                if (Equals(obj.Value, null))
+                {
+                    return 0;
+                }
+
+                return valueComparer.GetHashCode(obj.Value);
             }
         }
     }

backend/src/Squidex.Infrastructure/Queries/Optimizer.cs

@@ -24,7 +24,7 @@ namespace Squidex.Infrastructure.Queries
 
         public override FilterNode<TValue>? Visit(LogicalFilter<TValue> nodeIn)
         {
-            var pruned = nodeIn.Filters.Select(x => x.Accept(this)!).Where(x => x != null).ToList();
+            var pruned = nodeIn.Filters.Select(x => x.Accept(this)!).NotNull().ToList();
 
             if (pruned.Count == 1)
             {

backend/src/Squidex.Infrastructure/Queries/TransformVisitor.cs

@@ -18,7 +18,7 @@ namespace Squidex.Infrastructure.Queries
 
         public override FilterNode<TValue>? Visit(LogicalFilter<TValue> nodeIn)
         {
-            var inner = nodeIn.Filters.Select(x => x.Accept(this)!).Where(x => x != null).ToList();
+            var inner = nodeIn.Filters.Select(x => x.Accept(this)!).NotNull().ToList();
 
             return new LogicalFilter<TValue>(nodeIn.Type, inner);
         }

backend/tools/Migrate_01/MigrationPath.cs

@@ -11,6 +11,7 @@ using System.Linq;
 using Microsoft.Extensions.DependencyInjection;
 using Migrate_01.Migrations;
 using Migrate_01.Migrations.MongoDb;
+using Squidex.Infrastructure;
 using Squidex.Infrastructure.Migrations;
 
 namespace Migrate_01
@@ -32,7 +33,7 @@ namespace Migrate_01
                 return (CurrentVersion, null);
             }
 
-            var migrations = ResolveMigrators(version).Where(x => x != null).ToList();
+            var migrations = ResolveMigrators(version).NotNull().ToList();
 
             return (CurrentVersion, migrations);
         }