comparison mercurial/patch.py @ 35277:6ba79cf34f5e

patch: add within-line color diff capacity

The `diff' command usually writes deletion in red and insertions in green. This
patch adds within-line colors, to highlight which part of the lines differ.
Lines to compare are decided based on their similarity ratio, as computed by
difflib SequenceMatcher, with an arbitrary threshold (0.7) to decide at which
point two lines are considered entirely different (therefore no inline-diff
required).

The current implementation is kept behind an experimental flag in order to test
the effect on performance. In order to activate it, set inline-color-diff to
true in [experimental].

35276:205c3c6c1a51

from __future__ import absolute_import, print_function

import collections
import copy
import email
import errno
import hashlib
import os
import posixpath

    buildopts = {
        'nodates': get('nodates'),
        'showfunc': get('show_function', 'showfunc'),
        'context': get('unified', getter=ui.config),
    }

    if git:
        buildopts['git'] = get('git')

        # since this is in the experimental section, we need to call

    else:
        return difffn(opts, None)

def difflabel(func, *args, **kw):
    '''yields 2-tuples of (output, label) based on the output of func()'''
    headprefixes = [('diff', 'diff.diffline'),
                    ('copy', 'diff.extended'),
                    ('rename', 'diff.extended'),
                    ('old', 'diff.extended'),
                    ('new', 'diff.extended'),

                    ('-', 'diff.deleted'),
                    ('+', 'diff.inserted')]
    head = False
    for chunk in func(*args, **kw):
        lines = chunk.split('\n')
        for i, line in enumerate(lines):
            if i != 0:
                yield ('\n', '')
            if head:
                if line.startswith('@'):

                    if diffline:
                        for token in tabsplitter.findall(stripline):
                            if '\t' == token[0]:
                                yield (token, 'diff.tab')
                            else:
                                yield (token, label)
                    else:
                        yield (stripline, label)
                    break
            else:
                yield (line, '')
            if line != stripline:
                yield (line[len(stripline):], 'diff.trailingwhitespace')

def diffui(*args, **kw):
    '''like diff(), but yields 2-tuples of (output, label) for ui.write()'''
    return difflabel(diff, *args, **kw)

35277:6ba79cf34f5e

from __future__ import absolute_import, print_function

import collections
import copy
import difflib
import email
import errno
import hashlib
import os
import posixpath

    buildopts = {
        'nodates': get('nodates'),
        'showfunc': get('show_function', 'showfunc'),
        'context': get('unified', getter=ui.config),
    }
    buildopts['worddiff'] = ui.configbool('experimental', 'worddiff')

    if git:
        buildopts['git'] = get('git')

        # since this is in the experimental section, we need to call

    else:
        return difffn(opts, None)

def difflabel(func, *args, **kw):
    '''yields 2-tuples of (output, label) based on the output of func()'''
    inlinecolor = False
    if kw.get('opts'):
        inlinecolor = kw['opts'].worddiff
    headprefixes = [('diff', 'diff.diffline'),
                    ('copy', 'diff.extended'),
                    ('rename', 'diff.extended'),
                    ('old', 'diff.extended'),
                    ('new', 'diff.extended'),

                    ('-', 'diff.deleted'),
                    ('+', 'diff.inserted')]
    head = False
    for chunk in func(*args, **kw):
        lines = chunk.split('\n')
        matches = {}
        if inlinecolor:
            matches = _findmatches(lines)
        for i, line in enumerate(lines):
            if i != 0:
                yield ('\n', '')
            if head:
                if line.startswith('@'):

                    if diffline:
                        for token in tabsplitter.findall(stripline):
                            if '\t' == token[0]:
                                yield (token, 'diff.tab')
                            else:
                                if i in matches:
                                    for l, t in _inlinediff(
                                                  lines[i].rstrip(),
                                                  lines[matches[i]].rstrip(),
                                                  label):
                                        yield (t, l)
                                else:
                                    yield (token, label)
                    else:
                        yield (stripline, label)
                    break
            else:
                yield (line, '')
            if line != stripline:
                yield (line[len(stripline):], 'diff.trailingwhitespace')

def _findmatches(slist):
    '''Look for insertion matches to deletion and returns a dict of
    correspondences.
    '''
    lastmatch = 0
    matches = {}
    for i, line in enumerate(slist):
        if line == '':
            continue
        if line[0] == '-':
            lastmatch = max(lastmatch, i)
            newgroup = False
            for j, newline in enumerate(slist[lastmatch + 1:]):
                if newline == '':
                    continue
                if newline[0] == '-' and newgroup: # too far, no match
                    break
                if newline[0] == '+': # potential match
                    newgroup = True
                    sim = difflib.SequenceMatcher(None, line, newline).ratio()
                    if sim > 0.7:
                        lastmatch = lastmatch + 1 + j
                        matches[i] = lastmatch
                        matches[lastmatch] = i
                        break
    return matches

def _inlinediff(s1, s2, operation):
    '''Perform string diff to highlight specific changes.'''
    operation_skip = '+?' if operation == 'diff.deleted' else '-?'
    if operation == 'diff.deleted':
        s2, s1 = s1, s2

    buff = []
    # we never want to higlight the leading +-
    if operation == 'diff.deleted' and s2.startswith('-'):
        label = operation
        token = '-'
        s2 = s2[1:]
        s1 = s1[1:]
    elif operation == 'diff.inserted' and s1.startswith('+'):
        label = operation
        token = '+'
        s2 = s2[1:]
        s1 = s1[1:]

    s = difflib.ndiff(re.split(br'(\W)', s2), re.split(br'(\W)', s1))
    for part in s:
        if part[0] in operation_skip:
            continue
        l = operation + '.highlight'
        if part[0] in ' ':
            l = operation
        if l == label: # contiguous token with same label
            token += part[2:]
            continue
        else:
            buff.append((label, token))
            label = l
            token = part[2:]
    buff.append((label, token))

    return buff

def diffui(*args, **kw):
    '''like diff(), but yields 2-tuples of (output, label) for ui.write()'''
    return difflabel(diff, *args, **kw)