Globally cache a single TexManager instance.

anntzer · anntzer · commit 63b94ef8f8e3 · 2019-01-18T23:24:35.000+01:00
This allows sharing its caches across renderer instances.

(If it was up to me this class would be replaced by module-level
functions and a module-level cache, but heh.)
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -29,6 +29,7 @@
 """
 
 import copy
+import functools
 import glob
 import hashlib
 import logging
@@ -48,6 +49,8 @@
 class TexManager(object):
     """
     Convert strings to dvi files using TeX, caching the results to a directory.
+
+    Repeated calls to this constructor always return the same instance.
     """
 
     cachedir = mpl.get_cachedir()
@@ -95,8 +98,13 @@ class TexManager(object):
         ('text.latex.preamble', 'text.latex.unicode', 'text.latex.preview',
          'font.family') + tuple('font.' + n for n in font_families))
 
-    def __init__(self):
+    @functools.lru_cache()  # Always return the same instance.
+    def __new__(cls):
+        self = object.__new__(cls)
+        self._reinit()
+        return self
 
+    def _reinit(self):
         if self.texcache is None:
             raise RuntimeError('Cannot create TexManager, as there is no '
                                'cache directory available')
@@ -146,6 +154,8 @@ def __init__(self):
         self._font_preamble = '\n'.join(
             [r'\usepackage{type1cm}'] + cmd + [r'\usepackage{textcomp}'])
 
+        return self
+
     def get_basefile(self, tex, fontsize, dpi=None):
         """
         Return a filename based on a hash of the string, fontsize, and dpi.
@@ -169,7 +179,7 @@ def get_font_config(self):
                 # deepcopy may not be necessary, but feels more future-proof
                 self._rc_cache[k] = copy.deepcopy(rcParams[k])
             _log.debug('RE-INIT\nold fontconfig: %s', self._fontconfig)
-            self.__init__()
+            self._reinit()
         _log.debug('fontconfig: %s', self._fontconfig)
         return self._fontconfig
 
diff --git a/lib/matplotlib/textpath.py b/lib/matplotlib/textpath.py
@@ -24,9 +24,7 @@ def _get_adobe_standard_encoding():
 
 
 class TextToPath(object):
-    """
-    A class that convert a given text to a path using ttf fonts.
-    """
+    """A class that converts strings to paths."""
 
     FONT_SCALE = 100.
     DPI = 72
