hgweb: code selection without line numbers in file source view
All the source lines are put in a <pre> tag, which gives correct display and
copy&paste in both Chromium (WebKit) and FireFox: line numbers are not copied,
all the tabs and spaces are kept. This doesn't change the visual appearance
of the view compared to current hgweb version and doesn't use any JS code.
Also, stripes in this view are now generated clientside with CSS.
This implementation is chosen because other variants have important issues:
Strategy FF Chrome
current D,LT,E,T,L D,L
pre S,NW S,NW
pre/div/nbsp LT,E,T,TS,NW TS,NW
pre/div/br LT,E,T,NW NW
ol/li/nbsp LT,E,T,TS,AJ TS,AJ
ol/li/br LT,E,T,AJ AJ
pre/span LV LV
Legend
Strategies:
- current: implemented in hgweb before this patch, i.e. divs for each line,
and line numbers links in the div too
- pre: the whole code in one pre tag with newlines, all line numbers
in another one with 'float: left'
- pre/div/{nbsp,br}: same as just 'pre', but separate divs for each line and
or <br> instead of empty lines (otherwise they are not copied at all)
- ol/li/{nbsp,br}: a single ol with li's and divs for each line,
or <br> same as in previous strategy
- pre/span: this patch
Problems:
D = (very minor) display problems, like wrong width of leading tabs
LT = loses leading/trailing whitespace
E = loses embedded whitespace
B = loses blank lines
T = loses tabs
L = selects line numbers
LV = (only) visually selects line numbers
LVE = (only) visually selects line numbers at empty lines
S = no stripes (and no ability to easily highlight
lines-which-are-linked-at in the future)
TS = space copied instead of empty line
AJ = get anchor links only with JS (they work even without)
NW = no linewrap easily possible (in future)
As for browser versions compatibility, the CSS tricks used are supported in
(according to caniuse.com):
a) line numbers generation with 'content:' property and CSS counters:
IE 8+, all other popular browsers (in pre-WebKit Opera numbers are being copied)
b) stripes ('nth-child' selector):
IE 8+, FF 3.5+, Safari 3.2+, Opera 9.5+, all other popular browsers
c) line numbers are not visually selected ('user-select:' property):
IE 10+, Opera 15.0+, all other popular browsers
This patch is based on a demo implementation by
Martin Geisler <martin@geisler.net>.
# error.py - Mercurial exceptions
#
# Copyright 2005-2008 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Mercurial exceptions.
This allows us to catch exceptions at higher levels without forcing
imports.
"""
# Do not import anything here, please
class RevlogError(Exception):
pass
class LookupError(RevlogError, KeyError):
def __init__(self, name, index, message):
self.name = name
if isinstance(name, str) and len(name) == 20:
from node import short
name = short(name)
RevlogError.__init__(self, '%s@%s: %s' % (index, name, message))
def __str__(self):
return RevlogError.__str__(self)
class ManifestLookupError(LookupError):
pass
class CommandError(Exception):
"""Exception raised on errors in parsing the command line."""
class InterventionRequired(Exception):
"""Exception raised when a command requires human intervention."""
class Abort(Exception):
"""Raised if a command needs to print an error and exit."""
def __init__(self, *args, **kw):
Exception.__init__(self, *args)
self.hint = kw.get('hint')
class ConfigError(Abort):
'Exception raised when parsing config files'
class OutOfBandError(Exception):
'Exception raised when a remote repo reports failure'
class ParseError(Exception):
'Exception raised when parsing config files (msg[, pos])'
class RepoError(Exception):
def __init__(self, *args, **kw):
Exception.__init__(self, *args)
self.hint = kw.get('hint')
class RepoLookupError(RepoError):
pass
class CapabilityError(RepoError):
pass
class RequirementError(RepoError):
"""Exception raised if .hg/requires has an unknown entry."""
pass
class LockError(IOError):
def __init__(self, errno, strerror, filename, desc):
IOError.__init__(self, errno, strerror, filename)
self.desc = desc
class LockHeld(LockError):
def __init__(self, errno, filename, desc, locker):
LockError.__init__(self, errno, 'Lock held', filename, desc)
self.locker = locker
class LockUnavailable(LockError):
pass
class ResponseError(Exception):
"""Raised to print an error with part of output and exit."""
class UnknownCommand(Exception):
"""Exception raised if command is not in the command table."""
class AmbiguousCommand(Exception):
"""Exception raised if command shortcut matches more than one command."""
# derived from KeyboardInterrupt to simplify some breakout code
class SignalInterrupt(KeyboardInterrupt):
"""Exception raised on SIGTERM and SIGHUP."""
class SignatureError(Exception):
pass