Fix crash on ErasedType and covers_at_runtime

mypy/subtypes.py

@@ -1167,6 +1167,14 @@ def restrict_subtype_away(t: Type, s: Type, *, ignore_promotions: bool = False)
 def covers_at_runtime(item: Type, supertype: Type, ignore_promotions: bool) -> bool:
     """Will isinstance(item, supertype) always return True at runtime?"""
     item = get_proper_type(item)
+    supertype = get_proper_type(supertype)
+    if (isinstance(item, (ErasedType, DeletedType))
+            or isinstance(supertype, (ErasedType, DeletedType))):
+        # It might happen when working with `lambda` arguments.
+        # Basically, we cannot tell at this point: whether some type will cover
+        # `lambda`'s argument or not. But, `ErasedType` or `DeletedType`
+        # will break our code later in `erase_type` visitor.
+        return False
 
     # Since runtime type checks will ignore type arguments, erase the types.
     supertype = erase_type(supertype)

test-data/unit/check-inference.test

@@ -3210,3 +3210,24 @@ def test(seq: List[Union[Iterable, Any]]) -> None:
             k = [k]
             reveal_type(k)  # N: Revealed type is "builtins.list[Any]"
 [builtins fixtures/list.pyi]
+
+[case testErasedTypeRuntimeCoverage]
+# https://github.com/python/mypy/issues/11913
+from typing import TypeVar, Type, Generic, Callable, Iterable
+
+_S = TypeVar('_S')
+_T1 = TypeVar('_T1')
+
+class map(Generic[_S]):
+    def __init__(self, __func: Callable[[_T1], _S], __iter1: Iterable[_T1]) -> None: ...
+
+class DataType: ...
+T = TypeVar("T", bound=DataType)
+
+def collection_from_dict_value(model: Type[T]) -> None:
+    map(
+        # This line was failing:
+        lambda i: i if isinstance(i, model) else i,
+        ["asdf"]
+    )
+[builtins fixtures/isinstancelist.pyi]