ensure selection order. (#179)

Author: gmac

lib/graphql/stitching/executor/shaper.rb

@@ -30,10 +30,15 @@ def resolve_object_scope(raw_object, parent_type, selections, typename = nil)
           case node
           when GraphQL::Language::Nodes::Field
             field_name = node.alias || node.name
+            raw_value = raw_object.delete(field_name)
 
             if @request.query.get_field(parent_type, node.name).introspection?
-              if node.name == TYPENAME && parent_type == @root_type && node != TypeResolver::TYPENAME_EXPORT_NODE
-                raw_object[field_name] = @root_type.graphql_name
+              next if TypeResolver.export_key?(field_name)
+
+              raw_object[field_name] = if node.name == TYPENAME && parent_type == @root_type
+                @root_type.graphql_name
+              else
+                raw_value
               end
               next
             end
@@ -42,14 +47,14 @@ def resolve_object_scope(raw_object, parent_type, selections, typename = nil)
             named_type = node_type.unwrap
 
             raw_object[field_name] = if node_type.list?
-              resolve_list_scope(raw_object[field_name], Util.unwrap_non_null(node_type), node.selections)
+              resolve_list_scope(raw_value, Util.unwrap_non_null(node_type), node.selections)
             elsif Util.is_leaf_type?(named_type)
-              raw_object[field_name]
+              raw_value
             else
-              resolve_object_scope(raw_object[field_name], named_type, node.selections)
+              resolve_object_scope(raw_value, named_type, node.selections)
             end
 
-            return nil if raw_object[field_name].nil? && node_type.non_null?
+            return nil if node_type.non_null? && raw_object[field_name].nil?
 
           when GraphQL::Language::Nodes::InlineFragment
             fragment_type = node.type ? @supergraph.memoized_schema_types[node.type.name] : parent_type

lib/graphql/stitching/planner.rb

@@ -213,7 +213,7 @@ def extract_locale_selections(
         input_selections.each do |node|
           case node
           when GraphQL::Language::Nodes::Field
-            if node.alias&.start_with?(TypeResolver::EXPORT_PREFIX) && node != TypeResolver::TYPENAME_EXPORT_NODE
+            if node.alias&.start_with?(TypeResolver::EXPORT_PREFIX) && node.object_id != TypeResolver::TYPENAME_EXPORT_NODE.object_id
               raise StitchingError, %(Alias "#{node.alias}" is not allowed because "#{TypeResolver::EXPORT_PREFIX}" is a reserved prefix.)
             elsif node.name == TYPENAME
               locale_selections << node

test/graphql/stitching/executor/shaper_grooming_test.rb

@@ -112,6 +112,64 @@ def test_grooms_through_fragment_spreads
     assert_equal expected, GraphQL::Stitching::Executor::Shaper.new(request).perform!(raw)
   end
 
+  def test_grooms_returned_field_order_to_match_selection
+    schema_sdl = %|
+      type Shop {
+        name: String
+        currency: String
+      }
+      type Product {
+        title: String
+        price: Float
+        parent: Product
+      }
+      type Query {
+        products: [Product]!
+        shop: Shop
+      }
+    |
+    query = %|{
+      products {
+        title
+        price
+        parent {
+          price
+          title
+        }
+      }
+      shop {
+        name
+        currency
+      }
+    }|
+    request = GraphQL::Stitching::Request.new(
+      supergraph_from_schema(schema_sdl),
+      query,
+    )
+    raw = {
+      "shop" => {
+        "currency" => "USD",
+        "name" => "Dog Haus",
+      },
+      "products" => [
+        {
+          "parent" => { "title" => "Leash set", "price" => 25.99 },
+          "title" => "Collar",
+          "price" => 7.99,
+        },
+        {
+          "parent" => { "title" => "Bowl set", "price" => 19.99 },
+          "title" => "Bowl",
+          "price" => 5.99,
+        },
+      ],
+    }
+
+    expected = %|{"products":[{"title":"Collar","price":7.99,"parent":{"price":25.99,"title":"Leash set"}},{"title":"Bowl","price":5.99,"parent":{"price":19.99,"title":"Bowl set"}}],"shop":{"name":"Dog Haus","currency":"USD"}}|
+
+    assert_equal expected, GraphQL::Stitching::Executor::Shaper.new(request).perform!(raw).to_json
+  end
+
   def test_renames_root_query_typenames
     schema_sdl = "type Query { field: String }"
     source = %|

test/graphql/stitching/integration/introspection_test.rb

@@ -51,7 +51,7 @@ def test_performs_schema_introspection_with_other_stitching
       },
     }
 
-    assert_equal expected, result
+    assert_equal expected, result.to_h
   end
 
   def test_performs_type_introspection_with_other_stitching
@@ -83,6 +83,6 @@ def test_performs_type_introspection_with_other_stitching
       },
     }
 
-    assert_equal expected, result
+    assert_equal expected, result.to_h
   end
 end

test/graphql/stitching/planner/plan_introspection_test.rb

@@ -62,4 +62,13 @@ def test_errors_for_reserved_selection_alias
       ).plan
     end
   end
+
+  def test_errors_for_reserved_typehint_alias
+    assert_error %|Alias "_export___typename" is not allowed because "_export_" is a reserved prefix| do
+      GraphQL::Stitching::Request.new(
+        @supergraph,
+        %|{ a { _export___typename: __typename } }|,
+      ).plan
+    end
+  end
 end