diff --git a/pytorch_lightning/callbacks/progress.py b/pytorch_lightning/callbacks/progress.py index a770c6c9..fa7d0d7d 100644 --- a/pytorch_lightning/callbacks/progress.py +++ b/pytorch_lightning/callbacks/progress.py @@ -93,7 +93,7 @@ class ProgressBarBase(Callback): """ trainer = self.trainer total_val_batches = 0 - if trainer.fast_dev_run: + if trainer.fast_dev_run and trainer.val_dataloaders is not None: total_val_batches = len(trainer.val_dataloaders) elif not self.trainer.disable_validation: is_val_epoch = (trainer.current_epoch + 1) % trainer.check_val_every_n_epoch == 0 diff --git a/pytorch_lightning/trainer/evaluation_loop.py b/pytorch_lightning/trainer/evaluation_loop.py index b80066f4..23f7d0ed 100644 --- a/pytorch_lightning/trainer/evaluation_loop.py +++ b/pytorch_lightning/trainer/evaluation_loop.py @@ -360,6 +360,10 @@ class TrainerEvaluationLoopMixin(ABC): dataloaders = self.val_dataloaders max_batches = self.num_val_batches + # enable fast_dev_run without val loop + if dataloaders is None: + return + # cap max batches to 1 when using fast_dev_run if self.fast_dev_run: max_batches = 1