Fix issue with tex-encoding on non-Unicode platforms

oscargus · oscargus · commit 618e86d958ce · 2022-05-11T08:41:48.000+02:00
diff --git a/lib/matplotlib/tests/test_texmanager.py b/lib/matplotlib/tests/test_texmanager.py
@@ -39,3 +39,17 @@ def test_font_selection(rc, preamble, family):
     src = Path(tm.make_tex("hello, world", fontsize=12)).read_text()
     assert preamble in src
     assert [*re.findall(r"\\\w+family", src)] == [family]
+
+
+def test_unicode_characters():
+    # Smoke test to see that Unicode characters does not cause issues
+    # See #23019
+    plt.rcParams['text.usetex'] = True
+    fig, ax = plt.subplots()
+    ax.set_ylabel('\\textit{Velocity (\N{DEGREE SIGN}/sec)}')
+    ax.set_xlabel('\N{VULGAR FRACTION ONE QUARTER}Öøæ')
+
+    # Not all characters are supported though
+    # Should raise RuntimeError, NOT UnicodeDecodeError
+    with pytest.raises(RuntimeError):
+        ax.set_title('\N{snowman}')
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -243,7 +243,8 @@ def make_tex(cls, tex, fontsize):
         Return the file name.
         """
         texfile = cls.get_basefile(tex, fontsize) + ".tex"
-        Path(texfile).write_text(cls._get_tex_source(tex, fontsize))
+        Path(texfile).write_text(cls._get_tex_source(tex, fontsize),
+                                 encoding='utf-8')
         return texfile
 
     @classmethod
@@ -265,7 +266,8 @@ def _run_checked_subprocess(cls, command, tex, *, cwd=None):
                 '{exc}\n\n'.format(
                     prog=command[0],
                     tex=tex.encode('unicode_escape'),
-                    exc=exc.output.decode('utf-8'))) from exc
+                    exc=exc.output.decode('utf-8', 'backslashreplace'))
+                ) from exc
         _log.debug(report)
         return report
 
