Fix typing in `pl.trainer.config_validator` (#10803)

pyproject.toml

@@ -94,7 +94,6 @@ module = [
     "pytorch_lightning.profiler.pytorch",
     "pytorch_lightning.profiler.simple",
     "pytorch_lightning.trainer.callback_hook",
-    "pytorch_lightning.trainer.configuration_validator",
     "pytorch_lightning.trainer.connectors.accelerator_connector",
     "pytorch_lightning.trainer.connectors.callback_connector",
     "pytorch_lightning.trainer.connectors.checkpoint_connector",

pytorch_lightning/trainer/configuration_validator.py

@@ -28,6 +28,8 @@ def verify_loop_configurations(trainer: "pl.Trainer", model: "pl.LightningModule
         model: The model to check the configuration.
 
     """
+    if trainer.state.fn is None:
+        raise ValueError("Unexpected: Trainer state fn must be set before validating loop configuration.")
     if trainer.state.fn in (TrainerFn.FITTING, TrainerFn.TUNING):
         __verify_train_val_loop_configuration(trainer, model)
         __verify_manual_optimization_support(trainer, model)
@@ -221,7 +223,7 @@ def __verify_manual_optimization_support(trainer: "pl.Trainer", model: "pl.Light
         )
 
 
-def __check_training_step_requires_dataloader_iter(model: "pl.LightningModule"):
+def __check_training_step_requires_dataloader_iter(model: "pl.LightningModule") -> None:
     """Check if the current `training_step` is requesting `dataloader_iter`."""
     training_step_fx = model.training_step
     if is_param_in_hook_signature(training_step_fx, "dataloader_iter", explicit=True):

pytorch_lightning/trainer/trainer.py

@@ -551,7 +551,7 @@ class Trainer(
             )
 
         self._terminate_on_nan = terminate_on_nan
-        self.gradient_clip_val = gradient_clip_val
+        self.gradient_clip_val: Union[int, float] = gradient_clip_val
         self.gradient_clip_algorithm = (
             GradClipAlgorithmType(gradient_clip_algorithm.lower())
             if gradient_clip_algorithm is not None