Don't replace empty response with null. That empty response may be place holder for other async resource (Reference,Connection)

Author: Dragomir-Ivanov

schema/query/projection_evaluator.go

@@ -214,10 +214,6 @@ func evalProjection(ctx context.Context, p Projection, payload map[string]interf
 								return fmt.Errorf("%s: error resolving field handler on sub-field: %v", name, err)
 							}
 						}
-						// Return `null` for missing result instead of empty object
-						if m, ok := v.(map[string]interface{}); ok && len(m) == 0 {
-							v = nil
-						}
 						resMu.Lock()
 						res[name] = v
 						resMu.Unlock()

schema/query/projection_evaluator_test.go

@@ -236,7 +236,7 @@ func TestProjectionEval(t *testing.T) {
 			`reference{name}`,
 			`{"reference":"100"}`,
 			nil,
-			`{"reference":null}`,
+			`{"reference":{}}`,
 		},
 		{
 			"Connection#1",