Only check _metrics of subsuper nucleus if available

zblz · zblz · commit f83daa76942b · 2015-11-09T10:02:36.000Z
Fixes #5444
diff --git a/lib/matplotlib/mathtext.py b/lib/matplotlib/mathtext.py
@@ -2859,10 +2859,12 @@ def subsuper(self, s, loc, toks):
             new_children = nucleus.children
             if len(new_children):
                 # remove last kern
-                if isinstance(new_children[-1],Kern):
+                if (isinstance(new_children[-1],Kern) and
+                        hasattr(new_children[-2], '_metrics')):
                     new_children = new_children[:-1]
                 last_char = new_children[-1]
-                last_char.width = last_char._metrics.advance
+                if hasattr(last_char, '_metrics'):
+                    last_char.width = last_char._metrics.advance
             # create new Hlist without kerning
             nucleus = Hlist(new_children, do_kern=False)
         else:
diff --git a/lib/matplotlib/tests/test_mathtext.py b/lib/matplotlib/tests/test_mathtext.py
@@ -104,6 +104,7 @@
     r'testing$^{123}$',
     ' '.join('$\\' + p + '$' for p in sorted(mathtext.Parser._snowflake)),
     r'$6-2$; $-2$; $ -2$; ${-2}$; ${  -2}$; $20^{+3}_{-2}$',
+    r'$\overline{\omega}^x \frac{1}{2}_0^x$', # github issue #5444
 ]
 
 digits = "0123456789"

Original file line number	Diff line number	Diff line change
`@@ -104,6 +104,7 @@`
`104`	`104`	`r'testing$^{123}$',`
`105`	`105`	`' '.join('$\\' + p + '$' for p in sorted(mathtext.Parser._snowflake)),`
`106`	`106`	`r'$6-2$; $-2$; $ -2$; ${-2}$; ${ -2}$; $20^{+3}_{-2}$',`
	`107`	`+ r'$\overline{\omega}^x \frac{1}{2}_0^x$', # github issue #5444`
`107`	`108`	`]`
`108`	`109`
`109`	`110`	`digits = "0123456789"`