Add text.parse_math rcParams

oscargus · oscargus · commit d3d7acb88cc1 · 2022-02-24T20:45:13.000+01:00
diff --git a/lib/matplotlib/mpl-data/matplotlibrc b/lib/matplotlib/mpl-data/matplotlibrc
@@ -296,6 +296,8 @@
                          # Values  other than 0 or 6 have no defined meaning.
 #text.antialiased: True  # If True (default), the text will be antialiased.
                          # This only affects raster outputs.
+#text.parse_math: True  # Use mathtext if there is an even number of unescaped
+                        # dollar signs.
 
 
 ## ***************************************************************************
diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -918,6 +918,7 @@ def _convert_validator_spec(key, conv):
     "text.hinting_factor": validate_int,
     "text.kerning_factor": validate_int,
     "text.antialiased":    validate_bool,
+    "text.parse_math":     validate_bool,
 
     "mathtext.cal":            validate_font_properties,
     "mathtext.rm":             validate_font_properties,
diff --git a/lib/matplotlib/tests/test_text.py b/lib/matplotlib/tests/test_text.py
@@ -755,6 +755,20 @@ def test_parse_math():
         fig.canvas.draw()
 
 
+def test_parse_math_rcparams():
+    # Default is True
+    fig, ax = plt.subplots()
+    ax.text(0, 0, r"$ \wrong{math} $")
+    with pytest.raises(ValueError, match='Unknown symbol'):
+        fig.canvas.draw()
+
+    # Setting rcParams to False
+    plt.rcParams['text.parse_math'] = False
+    fig, ax = plt.subplots()
+    ax.text(0, 0, r"$ \wrong{math} $")
+    fig.canvas.draw()
+
+
 @image_comparison(['text_pdf_font42_kerning.pdf'], style='mpl20')
 def test_pdf_font42_kerning():
     plt.rcParams['pdf.fonttype'] = 42
diff --git a/lib/matplotlib/text.py b/lib/matplotlib/text.py
@@ -142,7 +142,7 @@ def __init__(self,
                  wrap=False,
                  transform_rotates_text=False,
                  *,
-                 parse_math=True,
+                 parse_math=None,
                  **kwargs
                  ):
         """
@@ -1289,11 +1289,15 @@ def set_parse_math(self, parse_math):
 
         Parameters
         ----------
-        parse_math : bool
+        parse_math : bool or None
             If False, this `Text` will never use mathtext.  If True, mathtext
             will be used if there is an even number of unescaped dollar signs.
+            ``None`` means to use :rc:`text.parse_math`
         """
-        self._parse_math = bool(parse_math)
+        if parse_math is None:
+            self._parse_math = mpl.rcParams['text.parse_math']
+        else:
+            self._parse_math = bool(parse_math)
 
     def get_parse_math(self):
         """Return whether mathtext parsing is considered for this `Text`."""
