Small style fix + microoptimization of _parse_enc.

Author: anntzer

lib/matplotlib/backends/backend_pdf.py

@@ -763,12 +763,11 @@ def _embedTeXFont(self, fontinfo):
 
         # Encoding (if needed)
         if fontinfo.encodingfile is not None:
-            enc = dviread._parse_enc(fontinfo.encodingfile)
-            differencesArray = [Name(ch) for ch in enc]
-            differencesArray = [0] + differencesArray
-            fontdict['Encoding'] = \
-                {'Type': Name('Encoding'),
-                 'Differences': differencesArray}
+            fontdict['Encoding'] = {
+                'Type': Name('Encoding'),
+                'Differences': [
+                    0, *map(Name, dviread._parse_enc(fontinfo.encodingfile))],
+            }
 
         # If no file is specified, stop short
         if fontinfo.fontfile is None:

lib/matplotlib/dviread.py

@@ -989,8 +989,7 @@ def _parse_enc(path):
         The nth entry of the list is the PostScript glyph name of the nth
         glyph.
     """
-    with open(path, encoding="ascii") as file:
-        no_comments = "\n".join(line.split("%")[0].rstrip() for line in file)
+    no_comments = re.sub("%.*", "", Path(path).read_text(encoding="ascii"))
     array = re.search(r"(?s)\[(.*)\]", no_comments).group(1)
     lines = [line for line in array.split() if line]
     if all(line.startswith("/") for line in lines):