Update smoke test

Delay the import ot torchaudio untill the CLI options are parsed.
Add option to set loglevel to DEBUG so that it's easy to see the issue
with external libraries.

Author: mthrok

test/smoke_test/smoke_test.py

@@ -1,31 +1,44 @@
 """Run smoke tests"""
-
 import argparse
+import logging
+
 
-import torchaudio  # noqa: F401
-import torchaudio.compliance.kaldi  # noqa: F401
-import torchaudio.datasets  # noqa: F401
-import torchaudio.functional  # noqa: F401
-import torchaudio.models  # noqa: F401
-import torchaudio.pipelines  # noqa: F401
-import torchaudio.sox_effects  # noqa: F401
-import torchaudio.transforms  # noqa: F401
-import torchaudio.utils  # noqa: F401
+def base_smoke_test():
+    import torchaudio  # noqa: F401
+    import torchaudio.compliance.kaldi  # noqa: F401
+    import torchaudio.datasets  # noqa: F401
+    import torchaudio.functional  # noqa: F401
+    import torchaudio.models  # noqa: F401
+    import torchaudio.pipelines  # noqa: F401
+    import torchaudio.sox_effects  # noqa: F401
+    import torchaudio.transforms  # noqa: F401
+    import torchaudio.utils  # noqa: F401
 
 
 def ffmpeg_test():
     from torchaudio.io import StreamReader  # noqa: F401
 
 
 def main() -> None:
+    options = _parse_args()
+
+    if options.debug:
+        logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.DEBUG)
+
+    base_smoke_test()
+    if options.ffmpeg:
+        ffmpeg_test()
+    print("Smoke test passed.")
+
+
+def _parse_args():
     parser = argparse.ArgumentParser()
 
     # Warning: Please note this option should not be widely used, only use it when absolutely necessary
     parser.add_argument("--no-ffmpeg", dest="ffmpeg", action="store_false")
+    parser.add_argument("--debug", action="store_true", help="Enable debug logging.")
 
-    options = parser.parse_args()
-    if options.ffmpeg:
-        ffmpeg_test()
+    return parser.parse_args()
 
 
 if __name__ == "__main__":