Implement nested four-level cache

jpjepko · jpjepko · commit c7699a09215e · 2022-12-12T17:03:26.000-05:00
Prevents putting too many files in a single folder
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -176,8 +176,18 @@ def get_basefile(cls, tex, fontsize, dpi=None):
         Return a filename based on a hash of the string, fontsize, and dpi.
         """
         src = cls._get_tex_source(tex, fontsize) + str(dpi)
+        filehash = hashlib.md5(src.encode('utf-8')).hexdigest()
+
+        nested_folders = Path()
+        num_letters, num_levels = 2, 2
+        for i in range(0, num_letters*num_levels, num_letters):
+            nested_folders = nested_folders / Path(filehash[i:i+2])
+
+        filepath = (Path(cls.texcache) / nested_folders)
+        filepath.mkdir(parents=True, exist_ok=True)
+
         return os.path.join(
-            cls.texcache, hashlib.md5(src.encode('utf-8')).hexdigest())
+               os.path.join(cls.texcache, nested_folders), filehash)
 
     @classmethod
     def get_font_preamble(cls):
