Summary

In #26989 I could remove the lines warning that a glyph was missing without breaking any tests:

I didn't remove the warnings cause I don't think we test what Ft2Font.load_char does when given a missing glyph. It's used in three places in the library:

• mathtext:

  matplotlib/lib/matplotlib/_mathtext.py

  Lines 329 to 333 in 978b402

  	class TruetypeFonts(Fonts, metaclass=abc.ABCMeta):
  	"""
  	A generic base class for all font setups that use Truetype fonts
  	(through FT2Font).
  	"""

• textpath:

  matplotlib/lib/matplotlib/textpath.py

  Lines 163 to 167 in 978b402

  	def get_glyphs_mathtext(self, prop, s, glyph_map=None,
  	return_new_glyphs_only=False):
  	"""
  	Parse mathtext string *s* and convert it to a (vertices, codes) pair.
  	"""

• backend_pdf:

  matplotlib/lib/matplotlib/backends/backend_pdf.py

  Lines 661 to 664 in 978b402

  	class PdfFile:
  	"""PDF file object."""
  	def __init__(self, filename, metadata=None):

Proposed fix

Minimally, there should be at least two tests of how load_char /the methods calling it handle missing glyphs - mathtext may be a good start. There should be one test for each codepath that triggers a missing glyph error. It would probably also be good to add some more tests for TextPath -> it mostly seems to be tested via gallery examples.