BUG: HTMLFormatter does not die on unicode frame GH6098

Author: y-p

doc/source/release.rst

@@ -155,6 +155,7 @@ Bug Fixes
   - Regression in ``.get(None)`` indexing from 0.12 (:issue:`5652`)
   - Subtle ``iloc`` indexing bug, surfaced in (:issue:`6059`)
   - Bug with insert of strings into DatetimeIndex (:issue:`5818`)
+  - Fixed unicode bug in to_html/HTML repr (:issue:`6098`)
 
 pandas 0.13.0
 -------------

pandas/core/format.py

@@ -767,7 +767,7 @@ def _column_header():
                                                          levels)):
                 name = self.columns.names[lnum]
                 row = [''] * (row_levels - 1) + ['' if name is None
-                                                 else str(name)]
+                                                 else com.pprint_thing(name)]
 
                 tags = {}
                 j = len(row)