src/cm/ext/diff.py
changeset 155 f436e2fef076
parent 154 8cb89c153140
parent 153 e4746a10edf5
child 156 6d447220fd1e
--- a/src/cm/ext/diff.py	Fri Feb 05 18:43:58 2010 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,271 +0,0 @@
-# -*- coding: utf-8 -*-
-#
-# Copyright (C) 2004-2009 Edgewall Software
-# Copyright (C) 2004-2006 Christopher Lenz <cmlenz@gmx.de>
-# All rights reserved.
-#
-# This software is licensed as described in the file COPYING, which
-# you should have received as part of this distribution. The terms
-# are also available at http://trac.edgewall.org/wiki/TracLicense.
-#
-# This software consists of voluntary contributions made by many
-# individuals. For the exact contribution history, see the revision
-# history and logs, available at http://trac.edgewall.org/log/.
-#
-# Author: Christopher Lenz <cmlenz@gmx.de>
-
-from trac.util.html import escape, Markup
-from trac.util.text import expandtabs
-
-from difflib import SequenceMatcher
-import re
-
-__all__ = ['get_diff_options', 'hdf_diff', 'diff_blocks', 'unified_diff']
-
-
-def _get_change_extent(str1, str2):
-    """
-    Determines the extent of differences between two strings. Returns a tuple
-    containing the offset at which the changes start, and the negative offset
-    at which the changes end. If the two strings have neither a common prefix
-    nor a common suffix, (0, 0) is returned.
-    """
-    start = 0
-    limit = min(len(str1), len(str2))
-    while start < limit and str1[start] == str2[start]:
-        start += 1
-    end = -1
-    limit = limit - start
-    while -end <= limit and str1[end] == str2[end]:
-        end -= 1
-    return (start, end + 1)
-
-def _get_opcodes(fromlines, tolines, ignore_blank_lines=False,
-                 ignore_case=False, ignore_space_changes=False):
-    """
-    Generator built on top of SequenceMatcher.get_opcodes().
-    
-    This function detects line changes that should be ignored and emits them
-    as tagged as 'equal', possibly joined with the preceding and/or following
-    'equal' block.
-    """
-
-    def is_ignorable(tag, fromlines, tolines):
-        if tag == 'delete' and ignore_blank_lines:
-            if ''.join(fromlines) == '':
-                return True
-        elif tag == 'insert' and ignore_blank_lines:
-            if ''.join(tolines) == '':
-                return True
-        elif tag == 'replace' and (ignore_case or ignore_space_changes):
-            if len(fromlines) != len(tolines):
-                return False
-            def f(str):
-                if ignore_case:
-                    str = str.lower()
-                if ignore_space_changes:
-                    str = ' '.join(str.split())
-                return str
-            for i in range(len(fromlines)):
-                if f(fromlines[i]) != f(tolines[i]):
-                    return False
-            return True
-
-    matcher = SequenceMatcher(None, fromlines, tolines)
-    previous = None
-    for tag, i1, i2, j1, j2 in matcher.get_opcodes():
-        if tag == 'equal':
-            if previous:
-                previous = (tag, previous[1], i2, previous[3], j2)
-            else:
-                previous = (tag, i1, i2, j1, j2)
-        else:
-            if is_ignorable(tag, fromlines[i1:i2], tolines[j1:j2]):
-                if previous:
-                    previous = 'equal', previous[1], i2, previous[3], j2
-                else:
-                    previous = 'equal', i1, i2, j1, j2
-                continue
-            if previous:
-                yield previous
-            yield tag, i1, i2, j1, j2
-            previous = None
-
-    if previous:
-        yield previous
-
-def _group_opcodes(opcodes, n=3):
-    """
-    Python 2.2 doesn't have SequenceMatcher.get_grouped_opcodes(), so let's
-    provide equivalent here. The opcodes parameter can be any iterable or
-    sequence.
-
-    This function can also be used to generate full-context diffs by passing 
-    None for the parameter n.
-    """
-    # Full context produces all the opcodes
-    if n is None:
-        yield list(opcodes)
-        return
-
-    # Otherwise we leave at most n lines with the tag 'equal' before and after
-    # every change
-    nn = n + n
-    group = []
-    for idx, (tag, i1, i2, j1, j2) in enumerate(opcodes):
-        if idx == 0 and tag == 'equal': # Fixup leading unchanged block
-            i1, j1 = max(i1, i2 - n), max(j1, j2 - n)
-        elif tag == 'equal' and i2 - i1 > nn:
-            group.append((tag, i1, min(i2, i1 + n), j1, min(j2, j1 + n)))
-            yield group
-            group = []
-            i1, j1 = max(i1, i2 - n), max(j1, j2 - n)
-        group.append((tag, i1, i2, j1 ,j2))
-
-    if group and not (len(group) == 1 and group[0][0] == 'equal'):
-        if group[-1][0] == 'equal': # Fixup trailing unchanged block
-            tag, i1, i2, j1, j2 = group[-1]
-            group[-1] = tag, i1, min(i2, i1 + n), j1, min(j2, j1 + n)
-        yield group
-
-def hdf_diff(*args, **kwargs):
-    return diff_blocks(*args, **kwargs)
-
-def diff_blocks(fromlines, tolines, context=None, tabwidth=8,
-                ignore_blank_lines=0, ignore_case=0, ignore_space_changes=0):
-    """Return an array that is adequate for adding to the data dictionary
-
-    See the diff_div.html template.
-    """
-
-    type_map = {'replace': 'mod', 'delete': 'rem', 'insert': 'add',
-                'equal': 'unmod'}
-
-    space_re = re.compile(' ( +)|^ ')
-    def htmlify(match):
-        div, mod = divmod(len(match.group(0)), 2)
-        return div * '&nbsp; ' + mod * '&nbsp;'
-
-    def markup_intraline_changes(opcodes):
-        for tag, i1, i2, j1, j2 in opcodes:
-            if tag == 'replace' and i2 - i1 == j2 - j1:
-                for i in range(i2 - i1):
-                    fromline, toline = fromlines[i1 + i], tolines[j1 + i]
-                    (start, end) = _get_change_extent(fromline, toline)
-                    if start != 0 or end != 0:
-                        last = end+len(fromline)
-                        fromlines[i1+i] = fromline[:start] + '\0' + fromline[start:last] + \
-                                       '\1' + fromline[last:]
-                        last = end+len(toline)
-                        tolines[j1+i] = toline[:start] + '\0' + toline[start:last] + \
-                                     '\1' + toline[last:]
-            yield tag, i1, i2, j1, j2
-
-    changes = []
-    opcodes = _get_opcodes(fromlines, tolines, ignore_blank_lines, ignore_case,
-                           ignore_space_changes)
-    for group in _group_opcodes(opcodes, context):
-        blocks = []
-        last_tag = None
-        for tag, i1, i2, j1, j2 in markup_intraline_changes(group):
-            if tag != last_tag:
-                blocks.append({'type': type_map[tag],
-                               'base': {'offset': i1, 'lines': []},
-                               'changed': {'offset': j1, 'lines': []}})
-            if tag == 'equal':
-                for line in fromlines[i1:i2]:
-                    line = line.expandtabs(tabwidth)
-                    line = space_re.sub(htmlify, escape(line, quotes=False))
-                    blocks[-1]['base']['lines'].append(Markup(unicode(line)))
-                for line in tolines[j1:j2]:
-                    line = line.expandtabs(tabwidth)
-                    line = space_re.sub(htmlify, escape(line, quotes=False))
-                    blocks[-1]['changed']['lines'].append(Markup(unicode(line)))
-            else:
-                if tag in ('replace', 'delete'):
-                    for line in fromlines[i1:i2]:
-                        line = expandtabs(line, tabwidth, '\0\1')
-                        line = escape(line, quotes=False)
-                        line = '<del>'.join([space_re.sub(htmlify, seg)
-                                             for seg in line.split('\0')])
-                        line = line.replace('\1', '</del>')
-                        blocks[-1]['base']['lines'].append(
-                            Markup(unicode(line)))
-                if tag in ('replace', 'insert'):
-                    for line in tolines[j1:j2]:
-                        line = expandtabs(line, tabwidth, '\0\1')
-                        line = escape(line, quotes=False)
-                        line = '<ins>'.join([space_re.sub(htmlify, seg)
-                                             for seg in line.split('\0')])
-                        line = line.replace('\1', '</ins>')
-                        blocks[-1]['changed']['lines'].append(
-                            Markup(unicode(line)))
-        changes.append(blocks)
-    return changes
-
-def unified_diff(fromlines, tolines, context=None, ignore_blank_lines=0,
-                 ignore_case=0, ignore_space_changes=0):
-    opcodes = _get_opcodes(fromlines, tolines, ignore_blank_lines, ignore_case,
-                           ignore_space_changes)
-    for group in _group_opcodes(opcodes, context):
-        i1, i2, j1, j2 = group[0][1], group[-1][2], group[0][3], group[-1][4]
-        if i1 == 0 and i2 == 0:
-            i1, i2 = -1, -1 # support for 'A'dd changes
-        yield '@@ -%d,%d +%d,%d @@' % (i1 + 1, i2 - i1, j1 + 1, j2 - j1)
-        for tag, i1, i2, j1, j2 in group:
-            if tag == 'equal':
-                for line in fromlines[i1:i2]:
-                    yield ' ' + line
-            else:
-                if tag in ('replace', 'delete'):
-                    for line in fromlines[i1:i2]:
-                        yield '-' + line
-                if tag in ('replace', 'insert'):
-                    for line in tolines[j1:j2]:
-                        yield '+' + line
-
-def get_diff_options(req):
-    options_data = {}
-    data = {'options': options_data}
-    
-    def get_bool_option(name, default=0):
-        pref = int(req.session.get('diff_' + name, default))
-        arg = int(req.args.has_key(name))
-        if req.args.has_key('update') and arg != pref:
-            req.session['diff_' + name] = arg
-        else:
-            arg = pref
-        return arg
-
-    pref = req.session.get('diff_style', 'inline')
-    style = req.args.get('style', pref)
-    if req.args.has_key('update') and style != pref:
-        req.session['diff_style'] = style
-    data['style'] = style
-
-    pref = int(req.session.get('diff_contextlines', 2))
-    try:
-        arg = int(req.args.get('contextlines', pref))
-    except ValueError:
-        arg = -1
-    if req.args.has_key('update') and arg != pref:
-        req.session['diff_contextlines'] = arg
-    options = ['-U%d' % arg]
-    options_data['contextlines'] = arg
-
-    arg = get_bool_option('ignoreblanklines')
-    if arg:
-        options.append('-B')
-    options_data['ignoreblanklines'] = arg
-
-    arg = get_bool_option('ignorecase')
-    if arg:
-        options.append('-i')
-    options_data['ignorecase'] = arg
-
-    arg = get_bool_option('ignorewhitespace')
-    if arg:
-        options.append('-b')
-    options_data['ignorewhitespace'] = arg
-
-    return (style, options, data)