From a3f0d4be50ab796b91bae2cb41ff975cad4e73f1 Mon Sep 17 00:00:00 2001
From: Oleh Prypin <oleh@pryp.in>
Date: Sun, 28 May 2023 20:26:10 +0200
Subject: [PATCH] Move logging DuplicateFilter to utils, enable it only in
 __main__

---
 mkdocs/__main__.py       |  4 ++++
 mkdocs/commands/build.py | 15 +--------------
 mkdocs/utils/__init__.py | 12 ++++++++++++
 3 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/mkdocs/__main__.py b/mkdocs/__main__.py
index a13e9378..0465cf41 100644
--- a/mkdocs/__main__.py
+++ b/mkdocs/__main__.py
@@ -46,6 +46,10 @@ def _showwarning(message, category, filename, lineno, file=None, line=None):
 
 
 def _enable_warnings():
+    from mkdocs.commands import build
+
+    build.log.addFilter(utils.DuplicateFilter())
+
     warnings.simplefilter('module', DeprecationWarning)
     warnings.showwarning = _showwarning
 
diff --git a/mkdocs/commands/build.py b/mkdocs/commands/build.py
index 82bec232..8bd57fe0 100644
--- a/mkdocs/commands/build.py
+++ b/mkdocs/commands/build.py
@@ -17,22 +17,9 @@ from mkdocs.exceptions import Abort, BuildError
 from mkdocs.structure.files import File, Files, InclusionLevel, _set_exclusions, get_files
 from mkdocs.structure.nav import Navigation, get_navigation
 from mkdocs.structure.pages import Page
-
-
-class DuplicateFilter:
-    """Avoid logging duplicate messages."""
-
-    def __init__(self) -> None:
-        self.msgs: set[str] = set()
-
-    def __call__(self, record: logging.LogRecord) -> bool:
-        rv = record.msg not in self.msgs
-        self.msgs.add(record.msg)
-        return rv
-
+from mkdocs.utils import DuplicateFilter  # noqa - legacy re-export
 
 log = logging.getLogger(__name__)
-log.addFilter(DuplicateFilter())
 
 
 def get_context(
diff --git a/mkdocs/utils/__init__.py b/mkdocs/utils/__init__.py
index 3eb55584..e906094c 100644
--- a/mkdocs/utils/__init__.py
+++ b/mkdocs/utils/__init__.py
@@ -442,6 +442,18 @@ def nest_paths(paths):
     return nested
 
 
+class DuplicateFilter:
+    """Avoid logging duplicate messages."""
+
+    def __init__(self) -> None:
+        self.msgs: set[str] = set()
+
+    def __call__(self, record: logging.LogRecord) -> bool:
+        rv = record.msg not in self.msgs
+        self.msgs.add(record.msg)
+        return rv
+
+
 class CountHandler(logging.NullHandler):
     """Counts all logged messages >= level."""