Merge pull request #20367 from aitikgupta/math-override

QuLogic · web-flow · commit 833658b87515 · 2021-06-29T04:48:32.000-04:00
Add parse_math in Text and default it False for TextBox
diff --git a/doc/api/next_api_changes/behavior/20367-AG.rst b/doc/api/next_api_changes/behavior/20367-AG.rst
@@ -0,0 +1,12 @@
+``Text`` allows a boolean *parse_math*
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`.Text` objects now allow a *parse_math* keyword-only argument
+which defaults to True. When it is passed as False, that text object
+will consider the string as a literal and will not try to parse it
+as a mathtext object.
+
+``TextBox`` defaults it to False
+--------------------------------
+`.TextBox` now defaults its text object's *parse_math** argument
+as False. 
diff --git a/lib/matplotlib/tests/test_text.py b/lib/matplotlib/tests/test_text.py
@@ -731,3 +731,13 @@ def test_unsupported_script(recwarn):
         [warn.message.args for warn in recwarn] ==
         [(r"Glyph 2534 (\N{BENGALI DIGIT ZERO}) missing from current font.",),
          (r"Matplotlib currently does not support Bengali natively.",)])
+
+
+def test_parse_math():
+    fig, ax = plt.subplots()
+    ax.text(0, 0, r"$ \wrong{math} $", parse_math=False)
+    fig.canvas.draw()
+
+    ax.text(0, 0, r"$ \wrong{math} $", parse_math=True)
+    with pytest.raises(ValueError, match='Unknown symbol'):
+        fig.canvas.draw()
diff --git a/lib/matplotlib/text.py b/lib/matplotlib/text.py
@@ -125,6 +125,8 @@ def __init__(self,
                  usetex=None,          # defaults to rcParams['text.usetex']
                  wrap=False,
                  transform_rotates_text=False,
+                 *,
+                 parse_math=True,
                  **kwargs
                  ):
         """
@@ -142,6 +144,7 @@ def __init__(self,
             color if color is not None else mpl.rcParams["text.color"])
         self.set_fontproperties(fontproperties)
         self.set_usetex(usetex)
+        self.set_parse_math(parse_math)
         self.set_wrap(wrap)
         self.set_verticalalignment(verticalalignment)
         self.set_horizontalalignment(horizontalalignment)
@@ -1237,6 +1240,8 @@ def _preprocess_math(self, s):
             if s == " ":
                 s = r"\ "
             return s, "TeX"
+        elif not self.get_parse_math():
+            return s, False
         elif cbook.is_math_text(s):
             return s, True
         else:
@@ -1274,6 +1279,25 @@ def get_usetex(self):
         """Return whether this `Text` object uses TeX for rendering."""
         return self._usetex
 
+    def set_parse_math(self, parse_math):
+        """
+        Override switch to enable/disable any mathtext
+        parsing for the given `Text` object.
+
+        Parameters
+        ----------
+        parse_math : bool
+            Whether to consider mathtext parsing for the string
+        """
+        self._parse_math = bool(parse_math)
+
+    def get_parse_math(self):
+        """
+        Return whether mathtext parsing is considered
+        for this `Text` object.
+        """
+        return self._parse_math
+
     def set_fontname(self, fontname):
         """
         Alias for `set_family`.
diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
@@ -1018,9 +1018,12 @@ def __init__(self, ax, label, initial='',
         self.label = ax.text(
             -label_pad, 0.5, label, transform=ax.transAxes,
             verticalalignment='center', horizontalalignment='right')
+
+        # TextBox's text object should not parse mathtext at all.
         self.text_disp = self.ax.text(
-            self.DIST_FROM_LEFT, 0.5, initial, transform=self.ax.transAxes,
-            verticalalignment='center', horizontalalignment='left')
+            self.DIST_FROM_LEFT, 0.5, initial,
+            transform=self.ax.transAxes, verticalalignment='center',
+            horizontalalignment='left', parse_math=False)
 
         self._observers = cbook.CallbackRegistry()
 
