Fixes and issue with custom directives and directive variables

src/HotChocolate/Stitching/src/Stitching/Delegation/ExtractFieldQuerySyntaxRewriter.cs

@@ -96,27 +96,6 @@ protected override FieldNode RewriteField(
         FieldNode node,
         Context context)
     {
-        var directives = node.Directives;
-
-        if (directives.Count > 0)
-        {
-            List<DirectiveNode>? temp = null;
-
-            foreach (var directive in directives)
-            {
-                if (BuiltInTypes.IsBuiltInType(directive.Name.Value))
-                {
-                    temp ??= new List<DirectiveNode>(directives);
-                    temp.Remove(directive);
-                }
-            }
-
-            if (temp is not null)
-            {
-                directives = temp;
-            }
-        }
-
         if (context.TypeContext is IComplexOutputType type &&
             type.Fields.TryGetField(node.Name.Value, out var field))
         {
@@ -133,7 +112,7 @@ protected override FieldNode RewriteField(
             }
 
             var required = RewriteNodeOrDefault(node.Required, cloned);
-            directives = RewriteList(directives, cloned);
+            var directives = RewriteList(node.Directives, cloned);
             var arguments = RewriteList(node.Arguments, cloned);
             var selectionSet = node.SelectionSet;
 
@@ -164,11 +143,6 @@ protected override FieldNode RewriteField(
             return OnRewriteField(node, cloned);
         }
 
-        if (!ReferenceEquals(directives, node.Directives))
-        {
-            return node.WithDirectives(directives);
-        }
-
         return node;
     }
 
@@ -224,6 +198,20 @@ protected override SelectionSetNode RewriteSelectionSet(
         return current;
     }
 
+    protected override DirectiveNode? RewriteDirective(DirectiveNode node, Context context)
+    {
+        if (node.Arguments.Count > 0)
+        {
+            var arguments = RewriteList(node.Arguments, context);
+            if (!ReferenceEquals(arguments, node.Arguments))
+            {
+                return node.WithArguments(arguments);
+            }
+        }
+
+        return base.RewriteDirective(node, context);
+    }
+
     private SelectionSetNode OnRewriteSelectionSet(
         SelectionSetNode node,
         Context context)

src/HotChocolate/Stitching/src/Stitching/Requests/MergeRequestRewriter.cs

@@ -36,21 +36,14 @@ public IDictionary<string, string> AddQuery(
 
         foreach (var variable in operation.VariableDefinitions)
         {
-            if (!_variables.ContainsKey(variable.Variable.Name.Value))
-            {
-                _variables.Add(variable.Variable.Name.Value, variable);
-            }
+            _variables.TryAdd(variable.Variable.Name.Value, variable);
         }
 
         _fields.AddRange(operation.SelectionSet.Selections.OfType<FieldNode>());
 
-        foreach (var fragment in rewritten.Definitions
-            .OfType<FragmentDefinitionNode>())
+        foreach (var fragment in rewritten.Definitions.OfType<FragmentDefinitionNode>())
         {
-            if (!_fragments.ContainsKey(fragment.Name.Value))
-            {
-                _fragments.Add(fragment.Name.Value, fragment);
-            }
+            _fragments.TryAdd(fragment.Name.Value, fragment);
         }
 
         return _aliases;

src/HotChocolate/Stitching/test/Stitching.Tests/Integration/FederatedSchemaTests.cs

@@ -106,18 +106,55 @@ public async Task AutoMerge_AddLocal_Field_Execute()
         // act
         var result = await executor.ExecuteAsync(
             @"{
-                    me {
-                        id
-                        name
-                        reviews {
-                            body
-                            product {
-                                upc
-                            }
+                me {
+                    id
+                    name
+                    reviews {
+                        body
+                        product {
+                            upc
                         }
                     }
-                    local
-                }");
+                }
+                local
+            }");
+
+        // assert
+        result.ToJson().MatchSnapshot();
+    }
+
+    [Fact]
+    public async Task Skip_Field_With_Variable()
+    {
+        // arrange
+        var httpClientFactory = CreateDefaultRemoteSchemas();
+
+        var executor =
+            await new ServiceCollection()
+                .AddSingleton(httpClientFactory)
+                .AddGraphQL()
+                .AddQueryType(d => d.Name("Query").Field("local").Resolve("I am local."))
+                .AddRemoteSchema(_accounts)
+                .AddRemoteSchema(_inventory)
+                .AddRemoteSchema(_products)
+                .AddRemoteSchema(_reviews)
+                .BuildRequestExecutorAsync();
+
+        // act
+        var result = await executor.ExecuteAsync(
+            @"query ($if: Boolean! = true) {
+                me {
+                    id
+                    name @skip(if: $if)
+                    reviews @skip(if: $if) {
+                        body
+                        product {
+                            upc
+                        }
+                    }
+                }
+                local
+            }");
 
         // assert
         result.ToJson().MatchSnapshot();