Do not space symbols in limits

oscargus · oscargus · commit 655ec515c462 · 2023-08-10T21:13:12.000+02:00
diff --git a/doc/sphinxext/math_symbol_table.py b/doc/sphinxext/math_symbol_table.py
@@ -67,8 +67,8 @@
      \hslash \blacksquare \blacktriangle \sharp \increment
      \prime \blacktriangledown \Im \flat \backprime \Re \natural
      \circledS \P \copyright \circledR \S \yen \checkmark \$
-     \cent \triangle \QED \sinewave \dag \ddag \perthousand
-     \lambdabar \L \l \degree \danger \maltese
+     \cent \triangle \QED \sinewave \dag \ddag \perthousand \ac
+     \lambdabar \L \l \degree \danger \maltese \clubsuitopen
      \i \hermitmatrix \sterling \nabla \mho""".split()],
 ]
 
@@ -83,7 +83,7 @@ def render_symbol(sym, ignore_variant=False):
             if sym not in (_mathtext.Parser._overunder_functions |
                            _mathtext.Parser._function_names):
                 sym = chr(_mathtext_data.tex2uni[sym])
-        return f'\\{sym}' if sym in ('\\', '|') else sym
+        return f'\\{sym}' if sym in ('\\', '|', '+', '-', '*') else sym
 
     lines = []
     for category, columns, syms in symbols:
@@ -145,6 +145,7 @@ def setup(app):
 
     # Add accents
     all_symbols.update({v[1:]: k for k, v in _mathtext.Parser._accent_map.items()})
+    all_symbols.update({v: v for v in _mathtext.Parser._wide_accents})
     print("SYMBOLS NOT IN TABLE:")
     for sym, val in _mathtext_data.tex2uni.items():
         if sym not in all_symbols:
diff --git a/doc/users/next_whats_new/mathtext_spacing.rst b/doc/users/next_whats_new/mathtext_spacing.rst
@@ -0,0 +1,5 @@
+``mathtext`` spacing corrections
+--------------------------------
+
+As consequence of the updated documentation, the spacing on a number of relational and
+operator symbols were classified like that and therefore will be spaced properly.
diff --git a/lib/matplotlib/_mathtext.py b/lib/matplotlib/_mathtext.py
@@ -1778,7 +1778,7 @@ class _MathStyle(enum.Enum):
       \triangleright     \ntriangleleft      \ntriangleright
       \trianglelefteq    \ntrianglelefteq    \trianglerighteq
       \ntrianglerighteq  \blacktriangleleft  \blacktriangleright
-      \equalparallel     \measuredrightangle \lrtriangle
+      \equalparallel     \measuredrightangle \varlrtriangle
       \Doteq        \Bumpeq       \Subset      \Supset
       \backepsilon  \because      \therefore   \bot
       \top          \bumpeq       \circeq      \coloneq
@@ -1799,7 +1799,7 @@ class _MathStyle(enum.Enum):
       \varniobar    \niobar       \bagmember   \ratio
       \Equiv        \stareq       \measeq      \arceq
       \rightassert  \rightModels  \smallin     \smallowns
-      \notsmallowns'''.split())
+      \notsmallowns \nsimeq'''.split())
 
     _arrow_symbols = set(r"""
      \leftarrow \longleftarrow \uparrow \Leftarrow \Longleftarrow
@@ -2154,9 +2154,11 @@ def symbol(self, s, loc, toks):
             # such as ${ -2}$, $ -2$, or $   -2$.
             prev_char = next((c for c in s[:loc][::-1] if c != ' '), '')
             # Binary operators at start of string should not be spaced
-            if (c in self._binary_operators and
-                    (len(s[:loc].split()) == 0 or prev_char == '{' or
-                     prev_char in self._left_delims)):
+            # Also, operators in sub- or superscripts should not be spaced
+            if (self._in_subscript_or_superscript or (
+                    c in self._binary_operators and (
+                    len(s[:loc].split()) == 0 or prev_char == '{' or
+                    prev_char in self._left_delims))):
                 return [char]
             else:
                 return [Hlist([self._make_space(0.2),
diff --git a/lib/matplotlib/_mathtext_data.py b/lib/matplotlib/_mathtext_data.py
@@ -910,7 +910,7 @@
     'O'                        : 216,
     'hookleftarrow'            : 8617,
     'trianglerighteq'          : 8885,
-    'nsime'                    : 8772,
+    'nsimeq'                   : 8772,
     'oe'                       : 339,
     'nwarrow'                  : 8598,
     'o'                        : 248,
@@ -1068,7 +1068,7 @@
     'hermitmatrix'             : 8889,
     'barvee'                   : 8893,
     'measuredrightangle'       : 8894,
-    'lrtriangle'               : 8895,
+    'varlrtriangle'            : 8895,
     'equalparallel'            : 8917,
     'npreccurlyeq'             : 8928,
     'nsucccurlyeq'             : 8929,
diff --git a/lib/matplotlib/tests/test_mathtext.py b/lib/matplotlib/tests/test_mathtext.py
@@ -525,7 +525,7 @@ def test_mathtext_operators():
     \ngtrsim \nlessgtr \ngtrless
     \cupleftarrow \oequal \rightassert
     \rightModels \hermitmatrix \barvee
-    \measuredrightangle \lrtriangle
+    \measuredrightangle \varlrtriangle
     \equalparallel \npreccurlyeq \nsucccurlyeq
     \nsqsubseteq \nsqsupseteq \sqsubsetneq
     \sqsupsetneq  \disin \varisins
