--- a/mercurial/encoding.py Fri Jul 11 18:04:51 2014 -0500
+++ b/mercurial/encoding.py Sun Jul 06 02:56:41 2014 +0900
@@ -165,6 +165,76 @@
if colwidth(t) == c:
return t
+def trim(s, width, ellipsis=''):
+ """Trim string 's' to at most 'width' columns (including 'ellipsis').
+
+ >>> ellipsis = '+++'
+ >>> from mercurial import encoding
+ >>> encoding.encoding = 'utf-8'
+ >>> t= '1234567890'
+ >>> print trim(t, 12, ellipsis=ellipsis)
+ 1234567890
+ >>> print trim(t, 10, ellipsis=ellipsis)
+ 1234567890
+ >>> print trim(t, 8, ellipsis=ellipsis)
+ 12345+++
+ >>> print trim(t, 8)
+ 12345678
+ >>> print trim(t, 3, ellipsis=ellipsis)
+ +++
+ >>> print trim(t, 1, ellipsis=ellipsis)
+ +
+ >>> u = u'\u3042\u3044\u3046\u3048\u304a' # 2 x 5 = 10 columns
+ >>> t = u.encode(encoding.encoding)
+ >>> print trim(t, 12, ellipsis=ellipsis)
+ \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a
+ >>> print trim(t, 10, ellipsis=ellipsis)
+ \xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xe3\x81\x88\xe3\x81\x8a
+ >>> print trim(t, 8, ellipsis=ellipsis)
+ \xe3\x81\x82\xe3\x81\x84+++
+ >>> print trim(t, 5)
+ \xe3\x81\x82\xe3\x81\x84
+ >>> print trim(t, 4, ellipsis=ellipsis)
+ +++
+ >>> t = '\x11\x22\x33\x44\x55\x66\x77\x88\x99\xaa' # invalid byte sequence
+ >>> print trim(t, 12, ellipsis=ellipsis)
+ \x11\x22\x33\x44\x55\x66\x77\x88\x99\xaa
+ >>> print trim(t, 10, ellipsis=ellipsis)
+ \x11\x22\x33\x44\x55\x66\x77\x88\x99\xaa
+ >>> print trim(t, 8, ellipsis=ellipsis)
+ \x11\x22\x33\x44\x55+++
+ >>> print trim(t, 8)
+ \x11\x22\x33\x44\x55\x66\x77\x88
+ >>> print trim(t, 3, ellipsis=ellipsis)
+ +++
+ >>> print trim(t, 1, ellipsis=ellipsis)
+ +
+ """
+ try:
+ u = s.decode(encoding)
+ except UnicodeDecodeError:
+ if len(s) <= width: # trimming is not needed
+ return s
+ width -= len(ellipsis)
+ if width <= 0: # no enough room even for ellipsis
+ return ellipsis[:width + len(ellipsis)]
+ return s[:width] + ellipsis
+
+ if ucolwidth(u) <= width: # trimming is not needed
+ return s
+
+ width -= len(ellipsis)
+ if width <= 0: # no enough room even for ellipsis
+ return ellipsis[:width + len(ellipsis)]
+
+ uslice = lambda i: u[:-i]
+ concat = lambda s: s + ellipsis
+ for i in xrange(1, len(u)):
+ usub = uslice(i)
+ if ucolwidth(usub) <= width:
+ return concat(usub.encode(encoding))
+ return ellipsis # no enough room for multi-column characters
+
def lower(s):
"best-effort encoding-aware case-folding of local string s"
try: