Fix font weight validation

timhoffm · timhoffm · commit 29b67801fd82 · 2019-09-15T19:44:36.000+02:00
diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -236,6 +236,20 @@ def validate_fonttype(s):
         return fonttype
 
 
+def validate_fontweight(s):
+    """Validate that *s* is a font weight, i.e. either an int or a string.
+    """
+    if isinstance(s, str):
+        try:
+            return int(s)
+        except ValueError:
+            return s
+    elif isinstance(s, numbers.Number):  # also numpy ints
+        return s
+    else:
+        raise ValueError(f'{s} is not a valid font weight.')
+
+
 _validate_standard_backends = ValidateInStrings(
     'backend', all_backends, ignorecase=True)
 _auto_backend_sentinel = object()
@@ -1095,7 +1109,7 @@ def _validate_linestyle(ls):
     'font.style':      ['normal', validate_string],
     'font.variant':    ['normal', validate_string],
     'font.stretch':    ['normal', validate_string],
-    'font.weight':     ['normal', validate_string],
+    'font.weight':     ['normal', validate_fontweight],
     'font.size':       [10, validate_float],      # Base font size in points
     'font.serif':      [['DejaVu Serif', 'Bitstream Vera Serif',
                          'Computer Modern Roman',
@@ -1174,7 +1188,7 @@ def _validate_linestyle(ls):
     'axes.titlesize':        ['large', validate_fontsize],  # fontsize of the
                                                             # axes title
     'axes.titlelocation':    ['center', validate_axes_titlelocation],  # alignment of axes title
-    'axes.titleweight':      ['normal', validate_string],  # font weight of axes title
+    'axes.titleweight':      ['normal', validate_fontweight],  # font weight of axes title
     'axes.titlecolor':       ['auto', validate_color_or_auto],  # font color of axes title
     'axes.titlepad':         [6.0, validate_float],  # pad from axes top to title in points
     'axes.grid':             [False, validate_bool],   # display grid or not
@@ -1187,7 +1201,7 @@ def _validate_linestyle(ls):
     'axes.labelsize':        ['medium', validate_fontsize],  # fontsize of the
                                                              # x any y labels
     'axes.labelpad':         [4.0, validate_float],  # space between label and axis
-    'axes.labelweight':      ['normal', validate_string],  # fontsize of the x any y labels
+    'axes.labelweight':      ['normal', validate_fontweight],  # fontsize of the x any y labels
     'axes.labelcolor':       ['black', validate_color],    # color of axis label
     'axes.formatter.limits': [[-5, 6], validate_nseq_int(2)],
                                # use scientific notation if log10
@@ -1320,7 +1334,7 @@ def _validate_linestyle(ls):
     ## figure props
     # figure title
     'figure.titlesize':   ['large', validate_fontsize],
-    'figure.titleweight': ['normal', validate_string],
+    'figure.titleweight': ['normal', validate_fontweight],
 
     # figure size in inches: width by height
     'figure.figsize':    [[6.4, 4.8], validate_nseq_float(2)],
