Don't consider 'object' always truthy #14510
Merged
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There are two reasons I'm proposing this change. First, we know that many subclasses of 'object' can be falsy. Second, mypy sometimes simplifies
object | Any
into justobject
. The latter was considered always truthy, while the prior one wasn't. Now both of them are treated consistently. An alternative fix would be to not simplify unions likeobject | Any
, but this seems a bit ad hoc.This only has an effect when the
truthy-bool
error code is explicitly enabled.Fixes #14480. This doesn't just fix the regression but fixes a more general issue.