matplotlib
diff --git a/‎lib/matplotlib/font_manager.py
Copy file name to clipboardExpand all lines: lib/matplotlib/font_manager.py
+26-1Lines changed: 26 additions & 1 deletion b/‎lib/matplotlib/font_manager.py
Copy file name to clipboardExpand all lines: lib/matplotlib/font_manager.py
+26-1Lines changed: 26 additions & 1 deletion
diff --git a/‎lib/matplotlib/tests/test_font_manager.py
Copy file name to clipboardExpand all lines: lib/matplotlib/tests/test_font_manager.py
+18-3Lines changed: 18 additions & 3 deletions b/‎lib/matplotlib/tests/test_font_manager.py
Copy file name to clipboardExpand all lines: lib/matplotlib/tests/test_font_manager.py
+18-3Lines changed: 18 additions & 3 deletions
@@ -50,6 +50,30 @@
 
 _log = logging.getLogger(__name__)
 
+
+class _findfontFilter(logging.Filter):
+    """
+    Suppress repeat font not found warning messages on a
+    per font and per message type basis
+    """
+    _msg_cache = set()
+
+    @classmethod
+    def clear_cache(cls):
+        _findfontFilter._msg_cache.clear()
+        _log.debug("findfont filter cache reset")
+
+    def filter(self, record):
+        if record.msg in self._msg_cache:
+            return False
+        if record.msg.startswith('findfont'):
+            _findfontFilter._msg_cache.add(record.msg)
+        return True
+
+_log_findfont_filter = _findfontFilter()
+_log.addFilter(_log_findfont_filter)
+_log.debug("findfont filter added to log")
+
 font_scalings = {
     'xx-small': 0.579,
     'x-small':  0.694,
@@ -1011,7 +1035,7 @@ class FontManager:
     # Increment this version number whenever the font cache data
     # format or behavior has changed and requires an existing font
     # cache files to be rebuilt.
-    __version__ = 330
+    __version__ = 331
 
     def __init__(self, size=None, weight='normal'):
         self._version = self.__version__
@@ -1576,6 +1600,7 @@ def _load_fontmanager(*, try_read_cache=True):
     fm = FontManager()
     json_dump(fm, fm_path)
     _log.info("generated new fontManager")
+    _findfontFilter._clear_cache()
     return fm
 
 
 
@@ -14,7 +14,7 @@
 
 from matplotlib.font_manager import (
     findfont, findSystemFonts, FontEntry, FontProperties, fontManager,
-    json_dump, json_load, get_font, is_opentype_cff_font,
+    _findfontFilter, json_dump, json_load, get_font, is_opentype_cff_font,
     MSUserFontDirectories, _get_fontconfig_fonts, ttfFontProperty)
 from matplotlib import cbook, ft2font, pyplot as plt, rc_context, figure as mfigure
 
@@ -241,12 +241,27 @@ def test_missing_family(caplog):
     plt.rcParams["font.sans-serif"] = ["this-font-does-not-exist"]
     with caplog.at_level("WARNING"):
         findfont("sans")
-    assert [rec.getMessage() for rec in caplog.records] == [
+    assert [rec.getMessage() in [
         "findfont: Font family ['sans'] not found. "
         "Falling back to DejaVu Sans.",
         "findfont: Generic family 'sans' not found because none of the "
         "following families were found: this-font-does-not-exist",
-    ]
+    ] for rec in caplog.records]
+    _findfontFilter.clear_cache()
+
+
+def test_not_found_filter(caplog):
+    plt.rcParams["font.sans-serif"] = ["this-font-does-not-exist"]
+
+    _findfontFilter.clear_cache()
+    _findfontFilter._msg_cache.add("findfont: Font family ['sans'] not found. "
+                                    "Falling back to DejaVu Sans.")
+    _findfontFilter._msg_cache.add("findfont: Generic family 'sans' not found "
+                                    "because none of the following families "
+                                    "were found: this-font-does-not-exist")
+    with caplog.at_level("WARNING"):
+        findfont("sans")
+    assert len(caplog.records) == 0
 
 
 def _test_threading():