log metrics for correct dataloader only (#10522)

Co-authored-by: tchaton <[email protected]>
Co-authored-by: Carlos Mocholí <[email protected]>

Author: 3 people

tests/trainer/logging_/test_eval_loop_logging.py

@@ -23,6 +23,7 @@
 
 from pytorch_lightning import callbacks, Trainer
 from pytorch_lightning.loggers import TensorBoardLogger
+from pytorch_lightning.trainer.connectors.logger_connector import LoggerConnector
 from pytorch_lightning.utilities.exceptions import MisconfigurationException
 from tests.helpers import BoringModel, RandomDataset
 
@@ -672,3 +673,29 @@ def val_dataloader(self):
         enable_model_summary=False,
     )
     trainer.fit(model)
+
+
+@pytest.mark.parametrize(
+    ["kwargs", "expected"],
+    [
+        ({"dl_idx": 0, "metrics": {"acc": 123}}, {"acc": 123}),
+        (
+            {"dl_idx": 0, "metrics": {"acc/dataloader_idx_0": 123, "acc/dataloader_idx_1": 321}},
+            {"acc/dataloader_idx_0": 123},
+        ),
+        (
+            {"dl_idx": 10, "metrics": {"acc/dataloader_idx_1": 123, "acc/dataloader_idx_10": 321}},
+            {"acc/dataloader_idx_10": 321},
+        ),
+        (
+            {"dl_idx": 3, "metrics": {"top_3_acc/dataloader_idx_0": 123, "top_3_acc/dataloader_idx_3": 321}},
+            {"top_3_acc/dataloader_idx_3": 321},
+        ),
+        # theoretical case, as `/dataloader_idx_3` would have been added
+        ({"dl_idx": 3, "metrics": {"top_3_acc": 123}}, {"top_3_acc": 123}),
+    ],
+)
+def test_filter_metrics_for_dataloader(kwargs, expected):
+    """Logged metrics should only include metrics from the concerned dataloader."""
+    actual = LoggerConnector._filter_metrics_for_dataloader(**kwargs)
+    assert actual == expected