matplotlib · anntzer · Apr 17, 2025
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
@@ -940,18 +940,13 @@ def dviFontName(self, dvifont):

        tex_font_map = dviread.PsfontsMap(dviread.find_tex_file('pdftex.map'))
        psfont = tex_font_map[dvifont.texname]
-        if psfont.filename is None:
-            raise ValueError(
-                "No usable font file found for {} (TeX: {}); "
-                "the font may lack a Type-1 version"
-                .format(psfont.psname, dvifont.texname))
-
        pdfname = next(self._internal_font_seq)
        _log.debug('Assigning font %s = %s (dvi)', pdfname, dvifont.texname)
        self._dviFontInfo[dvifont.texname] = types.SimpleNamespace(
            dvifont=dvifont,
            pdfname=pdfname,
-            fontfile=psfont.filename,
+            # raises ValueError if psfont.filename is None.
+            fontfile=str(dvifont.resolve_path()),
            basefont=psfont.psname,
            encodingfile=psfont.encoding,
            effects=psfont.effects)
@@ -996,11 +991,11 @@ def _embedTeXFont(self, fontinfo):

        # Widths
        widthsObject = self.reserveObject('font widths')
-        tfm = fontinfo.dvifont._tfm
+        font_metrics = fontinfo.dvifont._metrics
        # convert from TeX's 12.20 representation to 1/1000 text space units.
-        widths = [(1000 * metrics.tex_width) >> 20
-                  if (metrics := tfm.get_metrics(char)) else 0
-                  for char in range(max(tfm._glyph_metrics, default=-1) + 1)]
+        widths = [(1000 * glyph_metrics.tex_width) >> 20
+                  if (glyph_metrics := font_metrics.get_metrics(char)) else 0
+                  for char in range(max(font_metrics._glyph_metrics, default=-1) + 1)]
        self.writeObject(widthsObject, widths)

        # Font dictionary

diff --git a/lib/matplotlib/cbook.py b/lib/matplotlib/cbook.py
@@ -43,16 +43,20 @@ class _ExceptionInfo:
    users and result in incorrect tracebacks.
    """

-    def __init__(self, cls, *args):
+    def __init__(self, cls, *args, notes=None):
        self._cls = cls
        self._args = args
+        self._notes = notes if notes is not None else []

    @classmethod
    def from_exception(cls, exc):
-        return cls(type(exc), *exc.args)
+        return cls(type(exc), *exc.args, notes=getattr(exc, "__notes__", []))

    def to_exception(self):
-        return self._cls(*self._args)
+        exc = self._cls(*self._args)
+        for note in self._notes:
+            exc.add_note(note)
+        return exc


 def _get_running_interactive_framework():