From c277c90f12ce901d7e27cf3deb54706a9fe3364f Mon Sep 17 00:00:00 2001
From: Akash Kwatra <akashkw@gmail.com>
Date: Fri, 25 Feb 2022 13:55:19 -0800
Subject: [PATCH] Add unit tests

---
 pytorch_lightning/utilities/logger.py |  8 +++---
 tests/utilities/test_logger.py        | 37 +++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/pytorch_lightning/utilities/logger.py b/pytorch_lightning/utilities/logger.py
index 2bb541819eb1a..ef27761a2ec6e 100644
--- a/pytorch_lightning/utilities/logger.py
+++ b/pytorch_lightning/utilities/logger.py
@@ -148,17 +148,17 @@ def _add_prefix(metrics: Dict[str, float], prefix: str, separator: str) -> Dict[
     return metrics
 
 
-def _name(loggers: List[Any]) -> str:
+def _name(loggers: List[Any], separator: str = "_") -> str:
     if len(loggers) == 1:
         return loggers[0].name
     else:
         # Concatenate names together, removing duplicates and preserving order
-        return "_".join(dict.fromkeys(str(logger.name) for logger in loggers))
+        return separator.join(dict.fromkeys(str(logger.name) for logger in loggers))
 
 
-def _version(loggers: List[Any]) -> Union[int, str]:
+def _version(loggers: List[Any], separator: str = "_") -> Union[int, str]:
     if len(loggers) == 1:
         return loggers[0].version
     else:
         # Concatenate versions together, removing duplicates and preserving order
-        return "_".join(dict.fromkeys(str(logger.version) for logger in loggers))
+        return separator.join(dict.fromkeys(str(logger.version) for logger in loggers))
diff --git a/tests/utilities/test_logger.py b/tests/utilities/test_logger.py
index 8d9b495fb96bf..02d2795defb50 100644
--- a/tests/utilities/test_logger.py
+++ b/tests/utilities/test_logger.py
@@ -17,12 +17,15 @@
 import torch
 
 from pytorch_lightning import Trainer
+from pytorch_lightning.loggers import CSVLogger
 from pytorch_lightning.utilities.logger import (
     _add_prefix,
     _convert_params,
     _flatten_dict,
+    _name,
     _sanitize_callable_params,
     _sanitize_params,
+    _version,
 )
 
 
@@ -172,3 +175,37 @@ def test_add_prefix():
     assert "prefix-metric2" not in metrics
     assert metrics["prefix2_prefix-metric1"] == 1
     assert metrics["prefix2_prefix-metric2"] == 2
+
+
+def test_name(tmpdir):
+    """Verify names of loggers are concatenated properly."""
+    logger1 = CSVLogger(tmpdir, name="foo")
+    logger2 = CSVLogger(tmpdir, name="bar")
+    logger3 = CSVLogger(tmpdir, name="foo")
+    logger4 = CSVLogger(tmpdir, name="baz")
+    loggers = [logger1, logger2, logger3, logger4]
+    name = _name([])
+    assert name == ""
+    name = _name([logger3])
+    assert name == "foo"
+    name = _name(loggers)
+    assert name == "foo_bar_baz"
+    name = _name(loggers, "-")
+    assert name == "foo-bar-baz"
+
+
+def test_version(tmpdir):
+    """Verify names of loggers are concatenated properly."""
+    logger1 = CSVLogger(tmpdir, version=0)
+    logger2 = CSVLogger(tmpdir, version=2)
+    logger3 = CSVLogger(tmpdir, version=1)
+    logger4 = CSVLogger(tmpdir, version=0)
+    loggers = [logger1, logger2, logger3, logger4]
+    version = _version([])
+    assert version == ""
+    version = _version([logger3])
+    assert version == 1
+    version = _version(loggers)
+    assert version == "0_2_1"
+    version = _version(loggers, "-")
+    assert version == "0-2-1"