Properly take into account the length of the characters, fixing

some display issues (for example the cursor position
when entering stranges characters likes 癔)
This commit is contained in:
Florent Le Coz 2011-02-18 00:47:44 +01:00
parent 2f864c9fc1
commit 0d6ec6c5d3
2 changed files with 342 additions and 21 deletions

316
src/wcwidth.py Normal file
View file

@ -0,0 +1,316 @@
#/usr/bin/env python
# -*- encoding: utf-8
"""
* This is a Python implementation of wcwidth() and wcswidth(), based on the
* C implementation of the same functions (defined in IEEE Std 1002.1-2001)
* for Unicode:
*
* http://www.opengroup.org/onlinepubs/007904975/functions/wcwidth.html
* http://www.opengroup.org/onlinepubs/007904975/functions/wcswidth.html
*
* In fixed-width output devices, Latin characters all occupy a single
* "cell" position of equal width, whereas ideographic CJK characters
* occupy two such cells. Interoperability between terminal-line
* applications and (teletype-style) character terminals using the
* UTF-8 encoding requires agreement on which character should advance
* the cursor by how many cell positions. No established formal
* standards exist at present on which Unicode character shall occupy
* how many cell positions on character terminals. These routines are
* a first attempt of defining such behavior based on simple rules
* applied to data provided by the Unicode Consortium.
*
* For some graphical characters, the Unicode standard explicitly
* defines a character-cell width via the definition of the East Asian
* FullWidth (F), Wide (W), Half-width (H), and Narrow (Na) classes.
* In all these cases, there is no ambiguity about which width a
* terminal shall use. For characters in the East Asian Ambiguous (A)
* class, the width choice depends purely on a preference of backward
* compatibility with either historic CJK or Western practice.
* Choosing single-width for these characters is easy to justify as
* the appropriate long-term solution, as the CJK practice of
* displaying these characters as double-width comes from historic
* implementation simplicity (8-bit encoded characters were displayed
* single-width and 16-bit ones double-width, even for Greek,
* Cyrillic, etc.) and not any typographic considerations.
*
* Much less clear is the choice of width for the Not East Asian
* (Neutral) class. Existing practice does not dictate a width for any
* of these characters. It would nevertheless make sense
* typographically to allocate two character cells to characters such
* as for instance EM SPACE or VOLUME INTEGRAL, which cannot be
* represented adequately with a single-width glyph. The following
* routines at present merely assign a single-cell width to all
* neutral characters, in the interest of simplicity. This is not
* entirely satisfactory and should be reconsidered before
* establishing a formal standard in this area. At the moment, the
* decision which Not East Asian (Neutral) characters should be
* represented by double-width glyphs cannot yet be answered by
* applying a simple rule from the Unicode database content. Setting
* up a proper standard for the behavior of UTF-8 character terminals
* will require a careful analysis not only of each Unicode character,
* but also of each presentation form, something the author of these
* routines has avoided to do so far.
*
* http://www.unicode.org/unicode/reports/tr11/
*
* Markus Kuhn -- 2007-05-26 (Unicode 5.0)
* Berteun Damman - 2007-06-28 (Python version)
*
* Permission to use, copy, modify, and distribute this software
* for any purpose and without fee is hereby granted. The author
* disclaims all warranties with regard to this software.
*
* Latest C version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
"""
# auxiliary function for binary search in interval table, see below
def bisearch(ucs):
mn = 0
mx = len(combining_table) - 1
if ucs < combining_table[0][0] or ucs > combining_table[mx][1]:
return False
while mx >= mn:
mid = (mn + mx) // 2
if ucs > combining_table[mid][1]:
mn = mid + 1
elif ucs < combining_table[mid][0]:
mx = mid - 1
else:
return True
return False
"""
* The following two functions define the column width of an ISO 10646
* character as follows:
*
* - The null character (U+0000) has a column width of 0.
*
* - Other C0/C1 control characters and DEL will lead to a return
* value of -1.
*
* - Non-spacing and enclosing combining characters (general
* category code Mn or Me in the Unicode database) have a
* column width of 0.
*
* - SOFT HYPHEN (U+00AD) has a column width of 1.
*
* - Other format characters (general category code Cf in the Unicode
* database) and ZERO WIDTH SPACE (U+200B) have a column width of 0.
*
* - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF)
* have a column width of 0.
*
* - Spacing characters in the East Asian Wide (W) or East Asian
* Full-width (F) category as defined in Unicode Technical
* Report #11 have a column width of 2.
*
* - All remaining characters (including all printable
* ISO 8859-1 and WGL4 characters, Unicode control characters,
* etc.) have a column width of 1.
*
* This implementation assumes that wchar_t characters are encoded
* in ISO 10646.
"""
# sorted list of non-overlapping intervals of non-spacing characters
# generated by "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c"
combining_table = [
('\u0300', '\u036F'), ('\u0483', '\u0486'), ('\u0488', '\u0489'),
('\u0591', '\u05BD'), ('\u05BF', '\u05BF'), ('\u05C1', '\u05C2'),
('\u05C4', '\u05C5'), ('\u05C7', '\u05C7'), ('\u0600', '\u0603'),
('\u0610', '\u0615'), ('\u064B', '\u065E'), ('\u0670', '\u0670'),
('\u06D6', '\u06E4'), ('\u06E7', '\u06E8'), ('\u06EA', '\u06ED'),
('\u070F', '\u070F'), ('\u0711', '\u0711'), ('\u0730', '\u074A'),
('\u07A6', '\u07B0'), ('\u07EB', '\u07F3'), ('\u0901', '\u0902'),
('\u093C', '\u093C'), ('\u0941', '\u0948'), ('\u094D', '\u094D'),
('\u0951', '\u0954'), ('\u0962', '\u0963'), ('\u0981', '\u0981'),
('\u09BC', '\u09BC'), ('\u09C1', '\u09C4'), ('\u09CD', '\u09CD'),
('\u09E2', '\u09E3'), ('\u0A01', '\u0A02'), ('\u0A3C', '\u0A3C'),
('\u0A41', '\u0A42'), ('\u0A47', '\u0A48'), ('\u0A4B', '\u0A4D'),
('\u0A70', '\u0A71'), ('\u0A81', '\u0A82'), ('\u0ABC', '\u0ABC'),
('\u0AC1', '\u0AC5'), ('\u0AC7', '\u0AC8'), ('\u0ACD', '\u0ACD'),
('\u0AE2', '\u0AE3'), ('\u0B01', '\u0B01'), ('\u0B3C', '\u0B3C'),
('\u0B3F', '\u0B3F'), ('\u0B41', '\u0B43'), ('\u0B4D', '\u0B4D'),
('\u0B56', '\u0B56'), ('\u0B82', '\u0B82'), ('\u0BC0', '\u0BC0'),
('\u0BCD', '\u0BCD'), ('\u0C3E', '\u0C40'), ('\u0C46', '\u0C48'),
('\u0C4A', '\u0C4D'), ('\u0C55', '\u0C56'), ('\u0CBC', '\u0CBC'),
('\u0CBF', '\u0CBF'), ('\u0CC6', '\u0CC6'), ('\u0CCC', '\u0CCD'),
('\u0CE2', '\u0CE3'), ('\u0D41', '\u0D43'), ('\u0D4D', '\u0D4D'),
('\u0DCA', '\u0DCA'), ('\u0DD2', '\u0DD4'), ('\u0DD6', '\u0DD6'),
('\u0E31', '\u0E31'), ('\u0E34', '\u0E3A'), ('\u0E47', '\u0E4E'),
('\u0EB1', '\u0EB1'), ('\u0EB4', '\u0EB9'), ('\u0EBB', '\u0EBC'),
('\u0EC8', '\u0ECD'), ('\u0F18', '\u0F19'), ('\u0F35', '\u0F35'),
('\u0F37', '\u0F37'), ('\u0F39', '\u0F39'), ('\u0F71', '\u0F7E'),
('\u0F80', '\u0F84'), ('\u0F86', '\u0F87'), ('\u0F90', '\u0F97'),
('\u0F99', '\u0FBC'), ('\u0FC6', '\u0FC6'), ('\u102D', '\u1030'),
('\u1032', '\u1032'), ('\u1036', '\u1037'), ('\u1039', '\u1039'),
('\u1058', '\u1059'), ('\u1160', '\u11FF'), ('\u135F', '\u135F'),
('\u1712', '\u1714'), ('\u1732', '\u1734'), ('\u1752', '\u1753'),
('\u1772', '\u1773'), ('\u17B4', '\u17B5'), ('\u17B7', '\u17BD'),
('\u17C6', '\u17C6'), ('\u17C9', '\u17D3'), ('\u17DD', '\u17DD'),
('\u180B', '\u180D'), ('\u18A9', '\u18A9'), ('\u1920', '\u1922'),
('\u1927', '\u1928'), ('\u1932', '\u1932'), ('\u1939', '\u193B'),
('\u1A17', '\u1A18'), ('\u1B00', '\u1B03'), ('\u1B34', '\u1B34'),
('\u1B36', '\u1B3A'), ('\u1B3C', '\u1B3C'), ('\u1B42', '\u1B42'),
('\u1B6B', '\u1B73'), ('\u1DC0', '\u1DCA'), ('\u1DFE', '\u1DFF'),
('\u200B', '\u200F'), ('\u202A', '\u202E'), ('\u2060', '\u2063'),
('\u206A', '\u206F'), ('\u20D0', '\u20EF'), ('\u302A', '\u302F'),
('\u3099', '\u309A'), ('\uA806', '\uA806'), ('\uA80B', '\uA80B'),
('\uA825', '\uA826'), ('\uFB1E', '\uFB1E'), ('\uFE00', '\uFE0F'),
('\uFE20', '\uFE23'), ('\uFEFF', '\uFEFF'), ('\uFFF9', '\uFFFB'),
]
# XXX: There are some issues with Plane 1 Unicode characters on 32-bit
# systems. As these use UTF-16 internally they will use surrogate pairs
# to represent the character. I don't know how this works exactly though,
# therefore, until I've figured it out, if we're on a 32-bit system,
# we won't include these, otherwise we will.
if '\U0000FFFF' < '\U00010000':
combining_table.extend([
('\U00010A01', '\U00010A03'), ('\U00010A05', '\U00010A06'),
('\U00010A0C', '\U00010A0F'), ('\U00010A38', '\U00010A3A'),
('\U00010A3F', '\U00010A3F'), ('\U0001D167', '\U0001D169'),
('\U0001D173', '\U0001D182'), ('\U0001D185', '\U0001D18B'),
('\U0001D1AA', '\U0001D1AD'), ('\U0001D242', '\U0001D244'),
('\U000E0001', '\U000E0001'), ('\U000E0020', '\U000E007F'),
('\U000E0100', '\U000E01EF'),
])
def wcwidth(ucs):
if len(ucs) > 1:
raise TypeError('wcwidth() expected a character, '
'but string of length %d found' % (len(ucs),))
# test for 8-bit control characters
if ucs == '\u0000':
return 0
# non-printable chars.
if ucs < '\u0020' or (ucs >= '\u007f' and ucs < '\u00a0'):
return -1
# binary search in table of non-spacing characters
if bisearch(ucs):
return 0
# if we arrive here, ucs is not a combining or C0/C1 control character
return (1 +
(ucs >= '\u1100' and
(ucs <= '\u115f' or # Hangul Jamo init. consonants
ucs == '\u2329' or ucs == '\u232a' or
(ucs >= '\u2e80' and ucs <= '\ua4cf' and
ucs != '\u303f') or # CJK ... Yi
(ucs >= '\uac00' and ucs <= '\ud7a3') or # Hangul Syllables
(ucs >= '\uf900' and ucs <= '\ufaff') or # CJK Comp. Ideographs
(ucs >= '\ufe10' and ucs <= '\ufe19') or # Vertical forms
(ucs >= '\ufe30' and ucs <= '\ufe6f') or # CJK Comp. Forms
(ucs >= '\uff00' and ucs <= '\uff60') or # Fullwidth Forms
(ucs >= '\uffe0' and ucs <= '\uffe6') or
# XXX: '\U0000FFFF' < '\U00010000' is only True on 64-bit systems.
# On 32 bit systems it fails, but hopefully it won't cause chars to be
# misrepresented. It has to do with surrogate pairs, but I don't know
# how to fix this.
(('\U0000FFFF' < '\U00010000') and
(ucs >= '\U00020000' and ucs <= '\U0002fffd') or
(ucs >= '\U00030000' and ucs <= '\U0003fffd')))))
def wcswidth(s):
"""
Return the length of the passed string, using wcwidth on each char
instead of couting 1 for each one.
"""
width = 0
for c in s:
w = wcwidth(c)
if w < 0:
# If s contains a non-printable char, we should return -1.
# This includes newlines and tabs!
return -1
else:
width += w
return width
def widthcut(s, m):
"""
Return the first characters of s that can be contained in
a m length
"""
i = 0
width = 0
for c in s:
w = wcwidth(c)
if w < 0:
return None
else:
width += w
i += 1
if width > m:
return s[:i-1]
return s
def ljust(s, max, fillchar=" "):
"""
Like widthcut but adding chars at the end of the string until
max is reached
"""
if wcwidth(fillchar)!=1:
raise TypeError('widthpad() expected fillchar as a character, '
'but string of length %d found' % (len(fillchar),))
i = 0
width = 0
for c in s:
w = wcwidth(c)
if w < 0:
return None
else:
width += w
i += 1
if width==max:
return s[:i]
if width > max:
return s[:i-1]+fillchar
return s + fillchar*(max-width)
def rjust(s, max, fillchar=" "):
if wcwidth(fillchar)!=1:
raise TypeError('widthpad() expected fillchar as a character, '
'but string of length %d found' % (len(fillchar),))
i = 0
width = 0
for c in s:
w = wcwidth(c)
if w < 0:
return None
else:
width += w
i += 1
if width==max:
return s[:i]
if width > max:
return fillchar+s[:i-1]
return fillchar*(max-width) + s
if __name__ == '__main__':
import unicodedata
test_strings = [
'Pál Erdős', 'Kurt Gödel', 'Évariste Galois',
"Guillaume de l'Hôpital",
'ἄνδρα μοι ἔννεπε, μοῦσα, πολύτροπον, ὃς μάλα πολλὰ πλάγχθη',
]
for s in test_strings:
# d will be the decomposed version, this one should have the
# same display width, but it should have more characters.
d = unicodedata.normalize('NFD', s)
assert wcswidth(s) == wcswidth(d)
assert len(s) != len(d)
assert wcswidth('string with \n char') == -1
assert wcswidth('string with \t char') == -1
print('Minor testcase succeeded')

View file

@ -48,6 +48,7 @@ from sleekxmpp.xmlstream.stanzabase import JID
import theme
import common
import wcwidth
g_lock = Lock()
@ -391,10 +392,8 @@ class MucInfoWin(InfoWin):
self._refresh()
def write_room_name(self, room):
"""
"""
self.addstr('[', common.curses_color_pair(theme.COLOR_INFORMATION_BAR))
self.addnstr(room.name, len(room.name), common.curses_color_pair(theme.COLOR_GROUPCHAT_NAME))
self.addstr(room.name, common.curses_color_pair(theme.COLOR_GROUPCHAT_NAME))
self.addstr('] ', common.curses_color_pair(theme.COLOR_INFORMATION_BAR))
def write_disconnected(self, room):
@ -491,23 +490,27 @@ class TextWin(Win):
txt = message.txt
if not txt:
return 0
# length of the time
else:
txt = txt.replace('\t', ' ')
# length of the time
offset = 9+len(theme.CHAR_TIME_LEFT[:1])+len(theme.CHAR_TIME_RIGHT[:1])
if message.nickname and len(message.nickname) >= 30:
nick = message.nickname[:30]+''
if message.nickname and wcwidth.wcswidth(message.nickname) >= 25:
nick = message.nickname[:25]+''
else:
nick = message.nickname
if nick:
offset += len(nick) + 2 # + nick + spaces length
offset += wcwidth.wcswidth(nick) + 2 # + nick + spaces length
first = True
this_line_was_broken_by_space = False
nb = 0
while txt != '':
limit = txt[:self.width-offset].find('\n')
cutted_txt = wcwidth.widthcut(txt, self.width-offset) or txt[:self.width-offset]
limit = cutted_txt.find('\n')
if limit < 0:
# break between words if possible
if len(txt) >= self.width-offset:
limit = txt[:self.width-offset].rfind(' ')
if wcwidth.wcswidth(txt) >= self.width-offset:
cutted_txt = wcwidth.widthcut(txt, self.width-offset) or txt[:self.width-offset]
limit = cutted_txt.rfind(' ')
this_line_was_broken_by_space = True
if limit <= 0:
limit = self.width-offset
@ -528,15 +531,18 @@ class TextWin(Win):
}
l = Line(nick, color,
time,
txt[:limit], message.color,
wcwidth.widthcut(txt, limit) or txt[:limit], message.color,
offset,
message.colorized)
self.built_lines.append(l)
nb += 1
if this_line_was_broken_by_space:
txt = txt[limit+1:] # jump the space at the start of the line
else:
limit += 1 # jump the space at the start of the line
cutted_txt = wcwidth.widthcut(txt, limit)
if not cutted_txt:
txt = txt[limit:]
else:
txt = txt[len(cutted_txt):]
if txt.startswith('\n'):
txt = txt[1:]
first = False
@ -567,13 +573,11 @@ class TextWin(Win):
if line.nickname:
self.write_nickname(line.nickname, line.nickname_color)
self.write_text(y, line.text_offset, line.text, line.text_color, line.colorized)
if y != self.height-1 or (not line or line.text_offset+len(line.text) < self.width):
if y != self.height-1 or (not line or line.text_offset+wcwidth.wcswidth(line.text) < self.width):
self.addstr('\n')
self._refresh()
def write_line_separator(self):
"""
"""
self.addnstr('- '*(self.width//2-1)+'-', self.width, common.curses_color_pair(theme.COLOR_NEW_TEXT_SEPARATOR))
def write_text(self, y, x, txt, color, colorized):
@ -603,7 +607,7 @@ class TextWin(Win):
.replace('"(', '').replace(')"', '')
splitted = txt.split()
for word in splitted:
if word in list(special_words.keys()):
if word in special_words.keys():
self.addstr(word, common.curses_color_pair(special_words[word]))
elif word.startswith('(') and word.endswith(')'):
self.addstr('(', common.curses_color_pair(color))
@ -1000,9 +1004,9 @@ class Input(Win):
self.text = self.text[:self.pos+self.line_pos]+key+self.text[self.pos+self.line_pos:]
(y, x) = self._win.getyx()
if x == self.width-1:
self.line_pos += len(key)
self.line_pos += 1 # wcwidth.wcswidth(key)
else:
self.pos += len(key)
self.pos += 1 # wcwidth.wcswidth(key)
if reset:
self.rewrite_text()
if self.on_input:
@ -1030,12 +1034,13 @@ class Input(Win):
self._win.erase()
if self.color:
self._win.attron(common.curses_color_pair(self.color))
self.addstr(text[self.line_pos:self.line_pos+self.width-1])
displayed_text = text[self.line_pos:self.line_pos+self.width-1]
self.addstr(displayed_text)
if self.color:
(y, x) = self._win.getyx()
size = self.width-x
self.addnstr(' '*size, size, common.curses_color_pair(self.color))
self.addstr(0, self.pos, '') # WTF, this works but .move() doesn't…
self.addstr(0, wcwidth.wcswidth(displayed_text[:self.pos]), '')
if self.color:
self._win.attroff(common.curses_color_pair(self.color))
self._refresh()