Add xkcd style.

anntzer · anntzer · commit b5179690ca13 · 2019-07-31T16:29:23.000+02:00
diff --git a/doc/users/next_whats_new/2019-07-31-AL.rst b/doc/users/next_whats_new/2019-07-31-AL.rst
@@ -0,0 +1,5 @@
+xkcd style
+``````````
+
+The xkcd style previously available as `.pyplot.xkcd` is now also available as
+a regular style file, which can be used as ``matplotlib.style.use("xkcd")``.
diff --git a/lib/matplotlib/mpl-data/stylelib/xkcd.py b/lib/matplotlib/mpl-data/stylelib/xkcd.py
@@ -0,0 +1,21 @@
+from matplotlib import patheffects
+
+
+__mpl_style__ = {
+    "axes.edgecolor": "black",
+    "axes.grid": False,
+    "axes.linewidth": 1.5,
+    "axes.unicode_minus": False,
+    "figure.facecolor": "white",
+    "font.family": ["xkcd", "Humor Sans", "Comic Sans MS"],
+    "font.size": 14.0,
+    "grid.linewidth": 0.0,
+    "lines.linewidth": 2.0,
+    "path.effects": [patheffects.withStroke(linewidth=4, foreground="w")],
+    "path.sketch": (1, 100, 2),
+    "text.usetex": False,
+    "xtick.major.size": 8,
+    "xtick.major.width": 3,
+    "ytick.major.size": 8,
+    "ytick.major.width": 3,
+}
diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
@@ -399,24 +399,9 @@ def xkcd(scale=1, length=100, randomness=2):
     if rcParams['text.usetex']:
         raise RuntimeError(
             "xkcd mode is not compatible with text.usetex = True")
-
-    from matplotlib import patheffects
     return rc_context({
-        'font.family': ['xkcd', 'Humor Sans', 'Comic Sans MS'],
-        'font.size': 14.0,
+        **style.library["xkcd"],
         'path.sketch': (scale, length, randomness),
-        'path.effects': [patheffects.withStroke(linewidth=4, foreground="w")],
-        'axes.linewidth': 1.5,
-        'lines.linewidth': 2.0,
-        'figure.facecolor': 'white',
-        'grid.linewidth': 0.0,
-        'axes.grid': False,
-        'axes.unicode_minus': False,
-        'axes.edgecolor': 'black',
-        'xtick.major.size': 8,
-        'xtick.major.width': 3,
-        'ytick.major.size': 8,
-        'ytick.major.width': 3,
     })
 
 
diff --git a/lib/matplotlib/style/core.py b/lib/matplotlib/style/core.py
@@ -12,8 +12,10 @@
 """
 
 import contextlib
+import importlib
 import logging
 import os
+from pathlib import Path
 import re
 import warnings
 
@@ -148,8 +150,10 @@ def context(style, after_reset=False):
 
 def load_base_library():
     """Load style library defined in this package."""
-    library = read_style_directory(BASE_LIBRARY_PATH)
-    return library
+    return {
+        **read_style_directory(BASE_LIBRARY_PATH),
+        **_read_pystyle_base_directory(),
+    }
 
 
 def iter_user_libraries():
@@ -192,6 +196,27 @@ def read_style_directory(style_dir):
     return styles
 
 
+def _read_pystyle_base_directory():
+    """
+    Return directory of styles defined in *style_dir* as Python files.
+
+    Because Python style files can execute arbitrary code, this feature is only
+    used internally to load files provided by Matplotlib itself, not
+    user-provided style files.
+
+    A Python style is a Python module that exports a dict named
+    ``__mpl_style__``, from which a `RcParams` is constructed.  This convention
+    may be revisited if this feature ever becomes public.
+    """
+    styles = {}
+    for path in Path(BASE_LIBRARY_PATH).glob("*.py"):
+        spec = importlib.util.spec_from_file_location(path.stem, path)
+        module = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(module)
+        styles[path.stem] = mpl.RcParams(module.__mpl_style__)
+    return styles
+
+
 def update_nested_dict(main_dict, new_dict):
     """Update nested dict (only level of nesting) with new values.
 
