Preserve None when inlining bare return expressions

CHANGELOG.md

@@ -1,5 +1,7 @@
 # **Upcoming release**
 
+- #745 Preserve None when inlining a bare return into an expression. (@Narek-Khachikyan)
+
 - #895 patchedast Starred and keyword now consumes their syntactically expected and ** (@lieryan)
 - #896 patchedast cleanup and refactoring (@lieryan)
 - #905 Ignore `node_modules` directories by default when scanning project files and source folders. (@marcoeangeli)

rope/refactor/inline.py

@@ -587,7 +587,7 @@ def occurred_outside_skip(self, change_collector, occurrence):
         )
         if returns:
             name = returned
-            if name is None:
+            if not name:
                 name = "None"
             change_collector.add_change(
                 line_end,

ropetest/refactor/inlinetest.py

@@ -29,6 +29,30 @@ def _inline2(self, resource, offset, **kwds):
         self.project.do(changes)
         return self.mod.read()
 
+    def test_inlining_bare_return_in_generator_expression(self):
+        code = dedent("""\
+            class MyTokenizer:
+                def tokenize(self, text):
+                    return
+
+                def itokenize(self, text):
+                    return (t for t in self.tokenize(text))
+        """)
+        namespace = {}
+        exec(self._inline(code, code.index("tokenize(")), namespace)
+        with self.assertRaises(TypeError):
+            namespace["MyTokenizer"]().itokenize("")
+
+    def test_inlining_bare_return_as_expression(self):
+        code = dedent("""\
+            def f():
+                return
+            result = f()
+        """)
+        namespace = {}
+        exec(self._inline(code, code.index("f(")), namespace)
+        self.assertIsNone(namespace["result"])
+
     def test_simple_case(self):
         code = dedent("""\
             a_var = 10