[enh] add yield from node

redbaron/nodes.py

@@ -1205,6 +1205,15 @@ def _string_to_node(self, string, parent, on_attribute):
             raise Exception("Unhandled case")
 
 
+class YieldFromNode(Node):
+    def _string_to_node(self, string, parent, on_attribute):
+        if on_attribute == "value":
+            return Node.from_fst(baron.parse("yield from %s" % string)[0]["value"], parent=parent, on_attribute=on_attribute)
+
+        else:
+            raise Exception("Unhandled case")
+
+
 class YieldAtomNode(Node):
     def _string_to_node(self, string, parent, on_attribute):
         if on_attribute == "value":

tests/test_setter.py

@@ -1321,6 +1321,14 @@ def test_yield_atom_setattr_value_was_none():
     assert red.dumps() == "(yield a)"
 
 
+def test_yield_from_setattr_value():
+    red = RedBaron("yield from a")
+    red[0].value = "hop"
+    assert red.dumps() == "yield from hop"
+    with pytest.raises(Exception):
+        red[0].value = "def a(): pass\n"
+
+
 def test_list_comprehension_set_attr_result():
     red = RedBaron("[a for b in c]")
     red[0].result = "hop"