Fix missing empty directives in DSL nodes

gql/dsl.py

@@ -503,6 +503,7 @@ def executable_ast(self) -> OperationDefinitionNode:
             selection_set=self.selection_set,
             variable_definitions=self.variable_definitions.get_ast_definitions(),
             **({"name": NameNode(value=self.name)} if self.name else {}),
+            directives=(),
         )
 
     def __repr__(self) -> str:
@@ -597,6 +598,7 @@ def get_ast_definitions(self) -> Tuple[VariableDefinitionNode, ...]:
                 default_value=None
                 if var.default_value is None
                 else ast_from_value(var.default_value, var.type),
+                directives=(),
             )
             for var in self.variables.values()
             if var.type is not None  # only variables used
@@ -818,7 +820,11 @@ def __init__(
         """
         self.parent_type = parent_type
         self.field = field
-        self.ast_field = FieldNode(name=NameNode(value=name), arguments=())
+        self.ast_field = FieldNode(
+            name=NameNode(value=name),
+            arguments=(),
+            directives=(),
+        )
         self.dsl_type = dsl_type
 
         log.debug(f"Creating {self!r}")
@@ -950,7 +956,7 @@ def __init__(
 
         log.debug(f"Creating {self!r}")
 
-        self.ast_field = InlineFragmentNode()
+        self.ast_field = InlineFragmentNode(directives=())
 
         DSLSelector.__init__(self, *fields, **fields_with_alias)
 
@@ -1018,7 +1024,7 @@ def ast_field(self) -> FragmentSpreadNode:  # type: ignore
         `issue #4125 of mypy <https://github.com/python/mypy/issues/4125>`_.
         """
 
-        spread_node = FragmentSpreadNode()
+        spread_node = FragmentSpreadNode(directives=())
         spread_node.name = NameNode(value=self.name)
 
         return spread_node
@@ -1067,6 +1073,7 @@ def executable_ast(self) -> FragmentDefinitionNode:
             selection_set=self.selection_set,
             variable_definitions=self.variable_definitions.get_ast_definitions(),
             name=NameNode(value=self.name),
+            directives=(),
         )
 
     def __repr__(self) -> str:

tests/regressions/issue_447_dsl_missing_directives/test_dsl_directives.py

@@ -0,0 +1,59 @@
+from gql import Client
+from gql.dsl import DSLFragment, DSLQuery, DSLSchema, dsl_gql
+
+schema_str = """
+type MonsterForm {
+  sprites: MonsterFormSprites!
+}
+
+union SpriteUnion = Sprite | CopyOf
+
+type Query {
+  monster: [Monster!]!
+}
+
+type MonsterFormSprites {
+  actions: [SpriteUnion!]!
+}
+
+type CopyOf {
+  action: String!
+}
+
+type Monster {
+  manual(path: String!): MonsterForm
+}
+
+type Sprite {
+  action: String!
+}
+"""
+
+
+def test_issue_447():
+
+    client = Client(schema=schema_str)
+    ds = DSLSchema(client.schema)
+
+    sprite = DSLFragment("SpriteUnionAsSprite")
+    sprite.on(ds.Sprite)
+    sprite.select(
+        ds.Sprite.action,
+    )
+    copy_of = DSLFragment("SpriteUnionAsCopyOf")
+    copy_of.on(ds.CopyOf)
+    copy_of.select(
+        ds.CopyOf.action,
+    )
+
+    query = ds.Query.monster.select(
+        ds.Monster.manual(path="").select(
+            ds.MonsterForm.sprites.select(
+                ds.MonsterFormSprites.actions.select(sprite, copy_of),
+            ),
+        ),
+    )
+
+    q = dsl_gql(sprite, copy_of, DSLQuery(query))
+
+    client.validate(q)