Update (base update)

[ghstack-poisoned]

torch/_dynamo/variables/builtin.py

@@ -1510,9 +1510,18 @@ class BuiltinVariable(VariableTracker):
             assert istype(arg.sym_num, (torch.SymInt, torch.SymFloat))
             return SymNodeVariable.create(tx, arg.as_proxy() != 0)
 
-        if isinstance(arg, (ConstDictVariable, UserDefinedDictVariable)):
+        if isinstance(arg, ConstDictVariable):
             return ConstantVariable.create(len(arg.items) > 0)
-
+        if isinstance(arg, UserDefinedObjectVariable):
+            # for user defined objects, first try __bool__ if defined, else
+            # __len__. If neither is defined, then any instance is considered True
+            if arg.call_obj_hasattr(tx, "__bool__").value:
+                return arg.call_method(tx, "__bool__", [], {})
+            elif arg.call_obj_hasattr(tx, "__len__").value:
+                length = arg.call_method(tx, "__len__", [], {})
+                return ConstantVariable.create(length.value > 0)
+            else:
+                return ConstantVariable.create(True)
         # TODO handle more cases and merge this with this with `generic_jump`.
 
     def call_str(self, tx: "InstructionTranslator", arg):

torch/_dynamo/variables/dicts.py

@@ -1371,6 +1371,8 @@ class DictItemsVariable(DictViewVariable):
         return dict_items
 
     def call_method(self, tx, name, args, kwargs):
+        # TODO(guilhermeleobas): This should actually check if args[0]
+        # implements the mapping protocol.
         if name == "__eq__":
             assert len(args) == 1
             if isinstance(args[0], DictItemsVariable):

torch/_dynamo/variables/iter.py

@@ -246,11 +246,6 @@ class IteratorVariable(VariableTracker):
     def has_force_unpack_var_sequence(self, tx) -> bool:
         return True
 
-    def call_obj_hasattr(self, tx, name):
-        if name in ("__iter__", "__next__"):
-            return ConstantVariable.create(True)
-        return super().call_obj_hasattr(tx, name)
-
 
 class ObjectIteratorVariable(IteratorVariable):
     """