fix(logging): drop dead _HFSymlinksInfoFilter and redundant TasksManager demote filter

src/winml/modelkit/_warnings.py

@@ -101,73 +101,26 @@ def filter(self, record: logging.LogRecord) -> bool:
     )
 
     # =========================================================================
-    # py.warnings logger filters (for warnings routed via logging.captureWarnings)
+    # huggingface_hub: suppress the Windows "symlinks not supported" notice
     # =========================================================================
-
-    class _HFSymlinksInfoFilter(logging.Filter):
-        r"""Downgrade the huggingface_hub symlinks UserWarning from WARNING to INFO.
-
-        On Windows without Developer Mode, huggingface_hub warns that symlinks
-        are unsupported and the cache will use copies instead. This is cosmetic —
-        the cache still works, just without deduplication. WARNING is misleading
-        here; INFO is the appropriate level.
-
-        When warnings are routed via logging.captureWarnings(True), Python's
-        warnings.formatwarning() embeds the source filename in the log message
-        body ("path/to/huggingface_hub/file_download.py:1: UserWarning: ..."),
-        so we match against getMessage() rather than record.pathname (which
-        is always warnings.py in that path).
-
-        Before (WARNING level, always visible):
-            [09:12:34] WARNING  C:\\...\\huggingface_hub\\file_download.py:1:
-                                UserWarning: `huggingface_hub` cache-system uses
-                                symlinks by default to efficiently store
-                                duplicated files but your machine does not
-                                support them
-
-        After (INFO level, only visible with --verbose or -v):
-            [09:12:34] INFO     C:\\...\\huggingface_hub\\file_download.py:1:
-                                UserWarning: `huggingface_hub` cache-system uses
-                                symlinks by default to efficiently store
-                                duplicated files but your machine does not
-                                support them
-        """
-
-        def filter(self, record: logging.LogRecord) -> bool:
-            msg = record.getMessage()
-            if "symlinks" in msg and "huggingface_hub" in msg:
-                record.levelno = logging.INFO
-                record.levelname = "INFO"
-            return True
-
-    logging.getLogger("py.warnings").addFilter(_HFSymlinksInfoFilter())
-
-    # Suppress the huggingface_hub symlinks warning at the Python warnings level
-    # so it is hidden even before captureWarnings(True) is activated in build.py.
-    # When captureWarnings(True) is active, _HFSymlinksInfoFilter above handles
-    # the same message for loggers that need it at INFO (e.g. with --verbose).
+    # On Windows without Developer Mode, huggingface_hub emits a UserWarning that
+    # its cache will use file copies instead of symlinks. This is cosmetic — the
+    # cache still works, just without deduplication. Drop it at the Python
+    # warnings layer so it is hidden in every verbosity mode; this also stops it
+    # before captureWarnings(True) (activated in build.py) could route it to the
+    # py.warnings logger.
     warnings.filterwarnings(
         "ignore",
         message=r".*huggingface_hub.*cache-system.*symlinks.*",
         category=UserWarning,
     )
 
-    class _TasksManagerFilter(logging.Filter):
-        """Downgrade optimum TasksManager architecture-mismatch notice to INFO.
-
-        optimum logs a WARNING when TasksManager selects a different Auto class
-        than the one in config.architectures (e.g. AutoModelForSequenceClassification
-        vs RobertaForSequenceClassification).  This is expected behaviour for
-        WinML models and is purely informational.
-        """
-
-        def filter(self, record: logging.LogRecord) -> bool:
-            if "TasksManager returned" in record.getMessage():
-                record.levelno = logging.INFO
-                record.levelname = "INFO"
-            return True
-
-    logging.getLogger("optimum.exporters.tasks").addFilter(_TasksManagerFilter())
+    # NOTE: optimum's informational WARNINGs (e.g. "TasksManager returned ...",
+    # "No model type passed for the task ...") are gated by the verbosity-
+    # conditional ERROR floor on the `optimum` logger in utils/logging.py
+    # (configure_logging): hidden by default, shown at -v/-vv. A demote-to-INFO
+    # filter here would only relabel a record after the root-level gate has
+    # already passed it through — it would not suppress anything — so none is used.
 
     class _TransformersWeightsFilter(logging.Filter):
         """Suppress the transformers "weights not used" notice.

tests/unit/test_warnings_configure.py

@@ -2,94 +2,71 @@
 # Copyright (c) Microsoft Corporation. All rights reserved.
 # Licensed under the MIT License.
 # --------------------------------------------------------------------------
-"""Tests for _warnings._configure() filter behaviour."""
+"""Tests for _warnings._configure() suppression behaviour."""
 
 from __future__ import annotations
 
 import logging
 import warnings
-from typing import TYPE_CHECKING
-
-
-if TYPE_CHECKING:
-    import pytest
-
-
-def _get_hf_symlinks_filter() -> logging.Filter:
-    """Return the _HFSymlinksInfoFilter installed on the py.warnings logger."""
-    logger = logging.getLogger("py.warnings")
-    matches = [f for f in logger.filters if type(f).__name__ == "_HFSymlinksInfoFilter"]
-    assert matches, "_HFSymlinksInfoFilter not found on py.warnings logger"
-    return matches[0]
-
-
-def _emit_warning(message: str, filename: str) -> None:
-    """Emit a UserWarning through the real logging.captureWarnings path."""
-    logging.captureWarnings(True)
-    try:
-        warnings.warn_explicit(
-            message=message,
-            category=UserWarning,
-            filename=filename,
-            lineno=1,
-            registry={},  # fresh registry — always route to showwarning
-        )
-    finally:
-        logging.captureWarnings(False)
-
-
-class TestHFSymlinksInfoFilter:
-    """_HFSymlinksInfoFilter downgrades huggingface_hub symlinks warnings to INFO."""
-
-    def test_filter_is_installed(self) -> None:
-        """_configure() installs _HFSymlinksInfoFilter on the py.warnings logger."""
-        import winml.modelkit._warnings  # noqa: F401 — triggers _configure()
-
-        _get_hf_symlinks_filter()  # asserts filter exists
-
-    def test_downgrade_to_info(self, caplog: pytest.LogCaptureFixture) -> None:
-        """Warning from huggingface_hub containing 'symlinks' is downgraded to INFO."""
-        import winml.modelkit._warnings  # noqa: F401
-
-        with caplog.at_level(logging.DEBUG, logger="py.warnings"):
-            _emit_warning(
-                message=(
-                    "`huggingface_hub` cache-system uses symlinks by default to"
-                    " efficiently store duplicated files but your machine does not"
-                    " support them"
-                ),
-                filename="C:/fake/huggingface_hub/file_download.py",
-            )
-
-        records = [r for r in caplog.records if "symlinks" in r.getMessage()]
-        assert records, "No matching record captured"
-        assert records[0].levelno == logging.INFO
-        assert records[0].levelname == "INFO"
-
-    def test_unrelated_warning_unchanged(self, caplog: pytest.LogCaptureFixture) -> None:
-        """Records without 'symlinks' in message are not modified."""
-        import winml.modelkit._warnings  # noqa: F401
-
-        with caplog.at_level(logging.DEBUG, logger="py.warnings"):
-            _emit_warning(
-                message="Some other huggingface_hub warning without the keyword",
-                filename="C:/fake/huggingface_hub/file_download.py",
-            )
-
-        records = [r for r in caplog.records if "huggingface_hub" in r.getMessage()]
-        assert records, "No matching record captured"
-        assert records[0].levelno == logging.WARNING
-
-    def test_symlinks_from_other_module_unchanged(self, caplog: pytest.LogCaptureFixture) -> None:
-        """A 'symlinks' warning not from huggingface_hub is not modified."""
-        import winml.modelkit._warnings  # noqa: F401
-
-        with caplog.at_level(logging.DEBUG, logger="py.warnings"):
-            _emit_warning(
-                message="symlinks are not supported on this platform",
-                filename="C:/fake/other_library/utils.py",
-            )
-
-        records = [r for r in caplog.records if "symlinks" in r.getMessage()]
-        assert records, "No matching record captured"
-        assert records[0].levelno == logging.WARNING
+
+import pytest
+
+from winml.modelkit._warnings import _configure
+
+
+_HF_SYMLINKS_MESSAGE = (
+    "`huggingface_hub` cache-system uses symlinks by default to efficiently"
+    " store duplicated files but your machine does not support them"
+)
+
+# Loggers that _configure() attaches noise-suppression filters to. Calling
+# _configure() repeatedly (as these tests do) would otherwise accumulate
+# duplicate filter instances in global logging state.
+_FILTERED_LOGGERS = (
+    "diffusers.utils.import_utils",
+    "transformers.pipelines.base",
+    "transformers.models.auto.image_processing_auto",
+    "transformers.modeling_utils",
+)
+
+
+@pytest.fixture(autouse=True)
+def _restore_logging_filters():
+    """Snapshot and restore the filter lists of the loggers _configure() mutates."""
+    saved = {name: list(logging.getLogger(name).filters) for name in _FILTERED_LOGGERS}
+    yield
+    for name, filters in saved.items():
+        logging.getLogger(name).filters[:] = filters
+
+
+class TestHFSymlinksSuppression:
+    """_configure() drops the huggingface_hub symlinks UserWarning at the warnings layer.
+
+    The filter is a hard ``filterwarnings("ignore")`` rather than a demote-to-INFO
+    logging filter, so the warning never reaches the ``py.warnings`` logger and is
+    hidden in every verbosity mode.
+    """
+
+    def test_symlinks_warning_is_suppressed(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        """The huggingface_hub symlinks UserWarning is ignored, not surfaced."""
+        monkeypatch.delenv("WINMLCLI_SHOW_ALL_WARNINGS", raising=False)
+
+        with warnings.catch_warnings(record=True) as caught:
+            warnings.resetwarnings()
+            _configure()
+            warnings.warn(_HF_SYMLINKS_MESSAGE, UserWarning, stacklevel=2)
+
+        assert not [w for w in caught if "symlinks" in str(w.message)]
+
+    def test_unrelated_symlinks_warning_not_suppressed(
+        self, monkeypatch: pytest.MonkeyPatch
+    ) -> None:
+        """The ignore filter targets the HF message only; other warnings pass through."""
+        monkeypatch.delenv("WINMLCLI_SHOW_ALL_WARNINGS", raising=False)
+
+        with warnings.catch_warnings(record=True) as caught:
+            warnings.resetwarnings()
+            _configure()
+            warnings.warn("symlinks are unsupported on this platform", UserWarning, stacklevel=2)
+
+        assert [w for w in caught if "symlinks" in str(w.message)]

tests/unit/utils/test_logging.py

@@ -40,3 +40,17 @@ def test_library_loggers_follow_cli_level_when_verbose(verbosity, expected):
     # With -v/-vv the library loggers follow the CLI level so the detail is on demand.
     configure_logging(verbosity=verbosity)
     assert logging.getLogger("optimum").level == expected
+
+
+def test_optimum_child_logger_gated_by_parent_floor():
+    # The optimum "TasksManager returned ..." notice originates on the child logger
+    # optimum.exporters.tasks. With no demote filter, the parent ERROR floor must hide
+    # it by default and reveal it at -v (the floor follows the CLI level). This is what
+    # replaces the removed _TasksManagerFilter demote-to-INFO filter.
+    child = logging.getLogger("optimum.exporters.tasks")
+
+    configure_logging(verbosity=0)
+    assert not child.isEnabledFor(logging.WARNING)
+
+    configure_logging(verbosity=1)
+    assert child.isEnabledFor(logging.WARNING)