Dedupe texmanager preamble construction.

anntzer · anntzer · commit 7ccccc0858bf · 2019-12-12T10:34:05.000+01:00
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -192,6 +192,22 @@ def get_custom_preamble(self):
         """Return a string containing user additions to the tex preamble."""
         return rcParams['text.latex.preamble']
 
+    def _get_preamble(self):
+        unicode_preamble = "\n".join([
+            r"\usepackage[utf8]{inputenc}",
+            r"\DeclareUnicodeCharacter{2212}{\ensuremath{-}}",
+        ]) if rcParams["text.latex.unicode"] else ""
+        return "\n".join([
+            r"\documentclass{article}",
+            # Pass-through \mathdefault, which is used in non-usetex mode to
+            # use the default text font but was historically suppressed in
+            # usetex mode.
+            r"\newcommand{\mathdefault}[1]{#1}",
+            self._font_preamble,
+            unicode_preamble,
+            self.get_custom_preamble(),
+        ])
+
     def make_tex(self, tex, fontsize):
         """
         Generate a tex file to render the tex string at a specific font size.
@@ -200,30 +216,19 @@ def make_tex(self, tex, fontsize):
         """
         basefile = self.get_basefile(tex, fontsize)
         texfile = '%s.tex' % basefile
-        custom_preamble = self.get_custom_preamble()
         fontcmd = {'sans-serif': r'{\sffamily %s}',
                    'monospace': r'{\ttfamily %s}'}.get(self.font_family,
                                                        r'{\rmfamily %s}')
         tex = fontcmd % tex
 
-        unicode_preamble = "\n".join([
-            r"\usepackage[utf8]{inputenc}",
-            r"\DeclareUnicodeCharacter{2212}{\ensuremath{-}}",
-        ]) if rcParams["text.latex.unicode"] else ""
-
         s = r"""
-\documentclass{article}
-\newcommand{\mathdefault}[1]{#1}
-%s
-%s
 %s
 \usepackage[papersize={72in,72in},body={70in,70in},margin={1in,1in}]{geometry}
 \pagestyle{empty}
 \begin{document}
 \fontsize{%f}{%f}%s
 \end{document}
-""" % (self._font_preamble, unicode_preamble, custom_preamble,
-       fontsize, fontsize * 1.25, tex)
+""" % (self._get_preamble(), fontsize, fontsize * 1.25, tex)
         with open(texfile, 'wb') as fh:
             if rcParams['text.latex.unicode']:
                 fh.write(s.encode('utf8'))
@@ -251,25 +256,15 @@ def make_tex_preview(self, tex, fontsize):
         """
         basefile = self.get_basefile(tex, fontsize)
         texfile = '%s.tex' % basefile
-        custom_preamble = self.get_custom_preamble()
         fontcmd = {'sans-serif': r'{\sffamily %s}',
                    'monospace': r'{\ttfamily %s}'}.get(self.font_family,
                                                        r'{\rmfamily %s}')
         tex = fontcmd % tex
 
-        unicode_preamble = "\n".join([
-            r"\usepackage[utf8]{inputenc}",
-            r"\DeclareUnicodeCharacter{2212}{\ensuremath{-}}",
-        ]) if rcParams["text.latex.unicode"] else ""
-
         # newbox, setbox, immediate, etc. are used to find the box
         # extent of the rendered text.
 
         s = r"""
-\documentclass{article}
-\newcommand{\mathdefault}[1]{#1}
-%s
-%s
 %s
 \usepackage[active,showbox,tightpage]{preview}
 \usepackage[papersize={72in,72in},body={70in,70in},margin={1in,1in}]{geometry}
@@ -284,8 +279,7 @@ def make_tex_preview(self, tex, fontsize):
 {\fontsize{%f}{%f}%s}
 \end{preview}
 \end{document}
-""" % (self._font_preamble, unicode_preamble, custom_preamble,
-       fontsize, fontsize * 1.25, tex)
+""" % (self._get_preamble(), fontsize, fontsize * 1.25, tex)
         with open(texfile, 'wb') as fh:
             if rcParams['text.latex.unicode']:
                 fh.write(s.encode('utf8'))
