Merge pull request matplotlib#24239 from oscargus/mathtextbar

Fix mathtext rendering of `\|` and sizing of `|` and `\|`

Author: anntzer

lib/matplotlib/_mathtext.py

@@ -1455,7 +1455,7 @@ def __init__(self, c, height, depth, state, always=False, factor=None):
                 break
 
         shift = 0
-        if state.font != 0:
+        if state.font != 0 or len(alternatives) == 1:
             if factor is None:
                 factor = target_total / (char.height + char.depth)
             state.fontsize *= factor

lib/matplotlib/_mathtext_data.py

@@ -526,7 +526,7 @@
     'succnsim'                 : 8937,
     'gimel'                    : 8503,
     'vert'                     : 124,
-    '|'                        : 124,
+    '|'                        : 8214,
     'varrho'                   : 1009,
     'P'                        : 182,
     'approxident'              : 8779,