Properly handles ANSI escape sequences in table rows

.travis.yml

@@ -5,6 +5,7 @@ python:
   - "2.7"
   - "3.4"
   - "3.5"
+  - "3.6"
 addons:
   apt:
     packages:

Makefile

@@ -8,7 +8,7 @@ upload:
 	python setup.py sdist bdist_wininst upload
 
 test2:
-	python2 /usr/local/bin/nosetests --logging-level=INFO
+	python2 /Users/nirum/anaconda/bin/nosetests --logging-level=INFO
 
 test:
 	nosetests -v --with-coverage --cover-package=tableprint --logging-level=INFO

tableprint.py

@@ -15,10 +15,11 @@ from six import string_types
 from collections import namedtuple
 from numbers import Number
 import sys
+import re
 import numpy as np
 
 __all__ = ['table', 'header', 'row', 'hr', 'top', 'bottom', 'banner', 'dataframe', 'humantime']
-__version__ = '0.4.3'
+__version__ = '0.5.0'
 
 # set up table styles
 LineStyle = namedtuple('LineStyle', ('begin', 'hline', 'sep', 'end'))
@@ -149,7 +150,7 @@ def row(values, width=WIDTH, format_spec=FMT, style=STYLE):
     Parameters
     ----------
     values : array_like
-        An iterable array of data (numbers of strings), each value is printed in a separate column
+        An iterable array of data (numbers or strings), each value is printed in a separate column
 
     width : int
         The width of each column (Default: 11)
@@ -180,7 +181,7 @@ def row(values, width=WIDTH, format_spec=FMT, style=STYLE):
         datum, prec = val
 
         if isinstance(datum, string_types):
-            return ('{:>%i}' % width).format(datum)
+            return ('{:>%i}' % (width + _ansi_len(datum))).format(datum)
 
         elif isinstance(datum, Number):
             return ('{:>%i.%s}' % (width, prec)).format(datum)
@@ -318,6 +319,11 @@ def humantime(t):
     return timestr
 
 
+def _ansi_len(string):
+    """Extra length due to any ANSI sequences in the string."""
+    return len(string) - len(re.compile(r'\x1b[^m]*m').sub('', string))
+
+
 def _format_line(data, linestyle):
     """Formats a list of elements using the given line style"""
     return linestyle.begin + linestyle.sep.join(data) + linestyle.end