Merge pull request #9677 from anntzer/more-lru_cache

tacaswell · web-flow · commit 5730794685a7 · 2017-11-09T19:16:55.000-08:00
MNT: Rely more on lru_cache rather than custom caching.
diff --git a/doc/api/api_changes/removed-attributes.rst b/doc/api/api_changes/removed-attributes.rst
@@ -0,0 +1,4 @@
+Removed attributes
+``````````````````
+The unused `FONT_SCALE` and `fontd` attributes of the `RendererSVG` class have
+been removed.
diff --git a/lib/matplotlib/backends/backend_agg.py b/lib/matplotlib/backends/backend_agg.py
@@ -31,7 +31,6 @@
 from matplotlib import verbose, rcParams, __version__
 from matplotlib.backend_bases import (
     _Backend, FigureCanvasBase, FigureManagerBase, RendererBase, cursors)
-from matplotlib.cbook import maxdict
 from matplotlib.figure import Figure
 from matplotlib.font_manager import findfont, get_font
 from matplotlib.ft2font import (LOAD_FORCE_AUTOHINT, LOAD_NO_HINTING,
diff --git a/lib/matplotlib/backends/backend_svg.py b/lib/matplotlib/backends/backend_svg.py
@@ -19,7 +19,7 @@
      _Backend, FigureCanvasBase, FigureManagerBase, GraphicsContextBase,
     RendererBase)
 from matplotlib.backends.backend_mixed import MixedModeRenderer
-from matplotlib.cbook import is_writable_file_like, maxdict
+from matplotlib.cbook import is_writable_file_like
 from matplotlib.colors import rgb2hex
 from matplotlib.figure import Figure
 from matplotlib.font_manager import findfont, FontProperties, get_font
@@ -258,9 +258,6 @@ def generate_css(attrib={}):
 
 _capstyle_d = {'projecting' : 'square', 'butt' : 'butt', 'round': 'round',}
 class RendererSVG(RendererBase):
-    FONT_SCALE = 100.0
-    fontd = maxdict(50)
-
     def __init__(self, width, height, svgwriter, basename=None, image_dpi=72):
         self.width = width
         self.height = height
diff --git a/lib/matplotlib/colors.py b/lib/matplotlib/colors.py
@@ -101,8 +101,7 @@ def _is_nth_color(c):
 
 def is_color_like(c):
     """Return whether *c* can be interpreted as an RGB(A) color."""
-    # Special-case nth color syntax because it cannot be parsed during
-    # setup.
+    # Special-case nth color syntax because it cannot be parsed during setup.
     if _is_nth_color(c):
         return True
     try:
diff --git a/lib/matplotlib/font_manager.py b/lib/matplotlib/font_manager.py
@@ -985,6 +985,7 @@ def _normalize_font_family(family):
     return family
 
 
+@cbook.deprecated("2.2")
 class TempCache(object):
     """
     A class to store temporary caches that are (a) not saved to disk
@@ -1270,6 +1271,20 @@ def findfont(self, prop, fontext='ttf', directory=None,
         <http://www.w3.org/TR/1998/REC-CSS2-19980512/>`_ documentation
         for a description of the font finding algorithm.
         """
+        # Pass the relevant rcParams (and the font manager, as `self`) to
+        # _findfont_cached so to prevent using a stale cache entry after an
+        # rcParam was changed.
+        rc_params = tuple(tuple(rcParams[key]) for key in [
+            "font.serif", "font.sans-serif", "font.cursive", "font.fantasy",
+            "font.monospace"])
+        return self._findfont_cached(
+            prop, fontext, directory, fallback_to_default, rebuild_if_missing,
+            rc_params)
+
+    @lru_cache()
+    def _findfont_cached(self, prop, fontext, directory, fallback_to_default,
+                         rebuild_if_missing, rc_params):
+
         if not isinstance(prop, FontProperties):
             prop = FontProperties(prop)
         fname = prop.get_file()
@@ -1282,11 +1297,7 @@ def findfont(self, prop, fontext='ttf', directory=None,
         else:
             fontlist = self.ttflist
 
-        if directory is None:
-            cached = _lookup_cache[fontext].get(prop)
-            if cached is not None:
-                return cached
-        else:
+        if directory is not None:
             directory = os.path.normcase(directory)
 
         best_score = 1e64
@@ -1344,26 +1355,20 @@ def findfont(self, prop, fontext='ttf', directory=None,
             else:
                 raise ValueError("No valid font could be found")
 
-        if directory is None:
-            _lookup_cache[fontext].set(prop, result)
         return result
 
-_is_opentype_cff_font_cache = {}
+@lru_cache()
 def is_opentype_cff_font(filename):
     """
     Returns True if the given font is a Postscript Compact Font Format
     Font embedded in an OpenType wrapper.  Used by the PostScript and
     PDF backends that can not subset these fonts.
     """
     if os.path.splitext(filename)[1].lower() == '.otf':
-        result = _is_opentype_cff_font_cache.get(filename)
-        if result is None:
-            with open(filename, 'rb') as fd:
-                tag = fd.read(4)
-            result = (tag == b'OTTO')
-            _is_opentype_cff_font_cache[filename] = result
-        return result
-    return False
+        with open(filename, 'rb') as fd:
+            return fd.read(4) == b"OTTO"
+    else:
+        return False
 
 fontManager = None
 _fmcache = None
@@ -1431,11 +1436,6 @@ def findfont(prop, fontext='ttf'):
 
     fontManager = None
 
-    _lookup_cache = {
-        'ttf': TempCache(),
-        'afm': TempCache()
-    }
-
     def _rebuild():
         global fontManager
 
diff --git a/lib/matplotlib/mathtext.py b/lib/matplotlib/mathtext.py
@@ -25,6 +25,11 @@
 import unicodedata
 from warnings import warn
 
+try:
+    from functools import lru_cache
+except ImportError:  # Py2
+    from backports.functools_lru_cache import lru_cache
+
 from numpy import inf, isinf
 import numpy as np
 
@@ -3257,8 +3262,8 @@ def __init__(self, output):
         Create a MathTextParser for the given backend *output*.
         """
         self._output = output.lower()
-        self._cache = maxdict(50)
 
+    @lru_cache(50)
     def parse(self, s, dpi = 72, prop = None):
         """
         Parse the given math expression *s* at the given *dpi*.  If
@@ -3270,16 +3275,10 @@ def parse(self, s, dpi = 72, prop = None):
         The results are cached, so multiple calls to :meth:`parse`
         with the same expression should be fast.
         """
-        # There is a bug in Python 3.x where it leaks frame references,
-        # and therefore can't handle this caching
+
         if prop is None:
             prop = FontProperties()
 
-        cacheKey = (s, dpi, hash(prop))
-        result = self._cache.get(cacheKey)
-        if result is not None:
-            return result
-
         if self._output == 'ps' and rcParams['ps.useafm']:
             font_output = StandardPsFonts(prop)
         else:
@@ -3302,9 +3301,7 @@ def parse(self, s, dpi = 72, prop = None):
 
         box = self._parser.parse(s, font_output, fontsize, dpi)
         font_output.set_canvas_size(box.width, box.height, box.depth)
-        result = font_output.get_results(box)
-        self._cache[cacheKey] = result
-        return result
+        return font_output.get_results(box)
 
     def to_mask(self, texstr, dpi=120, fontsize=14):
         """
diff --git a/lib/matplotlib/path.py b/lib/matplotlib/path.py
@@ -20,6 +20,11 @@
 import math
 from weakref import WeakValueDictionary
 
+try:
+    from functools import lru_cache
+except ImportError:  # Py2
+    from backports.functools_lru_cache import lru_cache
+
 import numpy as np
 
 from . import _path, rcParams
@@ -942,27 +947,17 @@ def wedge(cls, theta1, theta2, n=None):
         """
         return cls.arc(theta1, theta2, n, True)
 
-    _hatch_dict = maxdict(8)
-
-    @classmethod
-    def hatch(cls, hatchpattern, density=6):
+    @staticmethod
+    @lru_cache(8)
+    def hatch(hatchpattern, density=6):
         """
         Given a hatch specifier, *hatchpattern*, generates a Path that
         can be used in a repeated hatching pattern.  *density* is the
         number of lines per unit square.
         """
         from matplotlib.hatch import get_path
-
-        if hatchpattern is None:
-            return None
-
-        hatch_path = cls._hatch_dict.get((hatchpattern, density))
-        if hatch_path is not None:
-            return hatch_path
-
-        hatch_path = get_path(hatchpattern, density)
-        cls._hatch_dict[(hatchpattern, density)] = hatch_path
-        return hatch_path
+        return (get_path(hatchpattern, density)
+                if hatchpattern is not None else None)
 
     def clip_to_bbox(self, bbox, inside=True):
         """
diff --git a/lib/matplotlib/textpath.py b/lib/matplotlib/textpath.py
@@ -33,9 +33,6 @@ class TextToPath(object):
     DPI = 72
 
     def __init__(self):
-        """
-        Initialization
-        """
         self.mathtext_parser = MathTextParser('path')
         self.tex_font_map = None
 
@@ -492,8 +489,7 @@ def _revalidate_path(self):
         necessary.
 
         """
-        if (self._invalid or
-            (self._cached_vertices is None)):
+        if self._invalid or self._cached_vertices is None:
             tr = Affine2D().scale(
                     self._size / text_to_path.FONT_SCALE,
                     self._size / text_to_path.FONT_SCALE).translate(*self._xy)
