From 7cb2bf7370408109fee25809fd85b2c30d7528d4 Mon Sep 17 00:00:00 2001
From: Andriy Svyryd <Andriy.Svyryd@microsoft.com>
Date: Wed, 9 Sep 2020 16:31:55 -0700
Subject: [PATCH] Remove extra ToList calls in MigrationsModelDiffer

---
 .../Migrations/Internal/MigrationsModelDiffer.cs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/EFCore.Relational/Migrations/Internal/MigrationsModelDiffer.cs b/src/EFCore.Relational/Migrations/Internal/MigrationsModelDiffer.cs
index 73291ab01b6..ed91236f62e 100644
--- a/src/EFCore.Relational/Migrations/Internal/MigrationsModelDiffer.cs
+++ b/src/EFCore.Relational/Migrations/Internal/MigrationsModelDiffer.cs
@@ -304,7 +304,7 @@ protected virtual IReadOnlyList<MigrationOperation> Sort(
                 }
             }
 
-            createTableOperations = createTableGraph.TopologicalSort(
+            createTableOperations = (List<CreateTableOperation>)createTableGraph.TopologicalSort(
                 (principalCreateTableOperation, createTableOperation, cyclicAddForeignKeyOperations) =>
                 {
                     foreach (var cyclicAddForeignKeyOperation in cyclicAddForeignKeyOperations)
@@ -321,7 +321,7 @@ protected virtual IReadOnlyList<MigrationOperation> Sort(
                     }
 
                     return true;
-                }).ToList();
+                });
 
             var dropTableGraph = new Multigraph<DropTableOperation, IForeignKeyConstraint>();
             dropTableGraph.AddVertices(dropTableOperations);
@@ -340,13 +340,13 @@ protected virtual IReadOnlyList<MigrationOperation> Sort(
             }
 
             var newDiffContext = new DiffContext();
-            dropTableOperations = dropTableGraph.TopologicalSort(
+            dropTableOperations = (List<DropTableOperation>)dropTableGraph.TopologicalSort(
                 (dropTableOperation, principalDropTableOperation, foreignKeys) =>
                 {
                     dropForeignKeyOperations.AddRange(foreignKeys.SelectMany(c => Remove(c, newDiffContext)));
 
                     return true;
-                }).ToList();
+                });
 
             return dropForeignKeyOperations
                 .Concat(dropTableOperations)
@@ -429,7 +429,6 @@ private IEnumerable<MigrationOperation> DiffAnnotations(
             IRelationalModel source,
             IRelationalModel target)
         {
-            var sourceMigrationsAnnotations = source?.GetAnnotations().ToList();
             var targetMigrationsAnnotations = target?.GetAnnotations().ToList();
 
             if (source == null)
@@ -446,17 +445,18 @@ private IEnumerable<MigrationOperation> DiffAnnotations(
 
             if (target == null)
             {
-                sourceMigrationsAnnotations = MigrationsAnnotations.ForRemove(source).ToList();
-                if (sourceMigrationsAnnotations.Count > 0)
+                var sourceMigrationsAnnotationsForRemoved = MigrationsAnnotations.ForRemove(source).ToList();
+                if (sourceMigrationsAnnotationsForRemoved.Count > 0)
                 {
                     var alterDatabaseOperation = new AlterDatabaseOperation();
-                    alterDatabaseOperation.OldDatabase.AddAnnotations(sourceMigrationsAnnotations);
+                    alterDatabaseOperation.OldDatabase.AddAnnotations(sourceMigrationsAnnotationsForRemoved);
                     yield return alterDatabaseOperation;
                 }
 
                 yield break;
             }
 
+            var sourceMigrationsAnnotations = source?.GetAnnotations().ToList();
             if (HasDifferences(sourceMigrationsAnnotations, targetMigrationsAnnotations))
             {
                 var alterDatabaseOperation = new AlterDatabaseOperation();