Fix PTL2.0 related ASR bugs in r1.21.0: Val metrics logging, None dat…

…aloader issue (NVIDIA#7531) (NVIDIA#7533)

* fix none dataloader issue ptl2



* ptl2.0 logging fixes for rnnt_models



---------

Signed-off-by: KunalDhawan <kunaldhawan97@gmail.com>
Co-authored-by: Kunal Dhawan <kunaldhawan97@gmail.com>
Co-authored-by: Nithin Rao <nithinrao.koluguri@gmail.com>

nemo/collections/asr/models/rnnt_models.py

@@ -772,7 +772,7 @@ def predict_step(self, batch, batch_idx, dataloader_idx=0):
         sample_id = sample_id.cpu().detach().numpy()
         return list(zip(sample_id, best_hyp_text))
 
-    def validation_step(self, batch, batch_idx, dataloader_idx=0):
+    def validation_pass(self, batch, batch_idx, dataloader_idx=0):
         signal, signal_len, transcript, transcript_len = batch
 
         # forward() only performs encoder forward
@@ -835,15 +835,21 @@ def validation_step(self, batch, batch_idx, dataloader_idx=0):
 
         return tensorboard_logs
 
+    def validation_step(self, batch, batch_idx, dataloader_idx=0):
+        metrics = self.validation_pass(batch, batch_idx, dataloader_idx)
+        if type(self.trainer.val_dataloaders) == list and len(self.trainer.val_dataloaders) > 1:
+            self.validation_step_outputs[dataloader_idx].append(metrics)
+        else:
+            self.validation_step_outputs.append(metrics)
+        return metrics
+
     def test_step(self, batch, batch_idx, dataloader_idx=0):
-        logs = self.validation_step(batch, batch_idx, dataloader_idx=dataloader_idx)
-        test_logs = {
-            'test_wer_num': logs['val_wer_num'],
-            'test_wer_denom': logs['val_wer_denom'],
-            # 'test_wer': logs['val_wer'],
-        }
-        if 'val_loss' in logs:
-            test_logs['test_loss'] = logs['val_loss']
+        logs = self.validation_pass(batch, batch_idx, dataloader_idx=dataloader_idx)
+        test_logs = {name.replace("val_", "test_"): value for name, value in logs.items()}
+        if type(self.trainer.test_dataloaders) == list and len(self.trainer.test_dataloaders) > 1:
+            self.test_step_outputs[dataloader_idx].append(test_logs)
+        else:
+            self.test_step_outputs.append(test_logs)
         return test_logs
 
     def multi_validation_epoch_end(self, outputs, dataloader_idx: int = 0):