Add a regression test

python · hauntsaninja · Jan 30, 2022 · Jan 5, 2022 · Jan 20, 2022 · Jan 20, 2022
commit dfd1a272ff10ec3fd86ff39785c4d291aa8a3952
diff --git a/test-data/unit/pythoneval.test b/test-data/unit/pythoneval.test
@@ -1573,3 +1573,28 @@ x: OrderedDict[str, str] = OrderedDict({})
 reveal_type(x)  # Revealed type is "collections.OrderedDict[builtins.str, builtins.int]"
 [out]
 _testTypingExtensionsOrderedDictAlias.py:3: note: Revealed type is "collections.OrderedDict[builtins.str, builtins.str]"
+
+[case testImplicit604TypeAliasWithCyclicImport]
+from was_builtins import foo
+reveal_type(foo)
+[file was_abc.pyi]
+from was_builtins import *
+[file was_builtins.pyi]
+import was_typing
+from was_typeshed import ReadableBuffer
+foo: ReadableBuffer
+[file was_collections.pyi]
+from was_builtins import *
+[file was_mmap.pyi]
+from was_builtins import *
+class mmap: ...
+[file was_typeshed.pyi]
+import was_mmap
+WriteableBuffer = was_mmap.mmap
+ReadableBuffer = str | WriteableBuffer
+[file was_typing.pyi]
+from was_builtins import *
+import was_abc
+import was_collections
+[out]
+_testImplicit604TypeAliasWithCyclicImport.py:2: note: Revealed type is "Union[builtins.str, was_mmap.mmap]"