mercurial/pure/diffhelpers.py
author Gregory Szorc <gregory.szorc@gmail.com>
Wed, 14 Mar 2018 13:57:52 -0700
changeset 37058 61393f888dfe
parent 27336 80214358ac88
child 37566 f53b55b162f4
permissions -rw-r--r--
wireproto: define and implement responses in framing protocol Previously, we only had client-side frame types defined. This commit defines and implements basic support for server-side frame types. We introduce two frame types - one for representing the raw bytes result of a command and another for representing error results. The types are quite primitive and behavior will expand over time. But you have to start somewhere. Our server reactor gains methods to react to an intent to send a response. Again, following the "sans I/O" pattern, the reactor doesn't actually send the data. Instead, it gives the caller a generator to frames that it can send out over the wire. Differential Revision: https://phab.mercurial-scm.org/D2858

# diffhelpers.py - pure Python implementation of diffhelpers.c
#
# Copyright 2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

def addlines(fp, hunk, lena, lenb, a, b):
    while True:
        todoa = lena - len(a)
        todob = lenb - len(b)
        num = max(todoa, todob)
        if num == 0:
            break
        for i in xrange(num):
            s = fp.readline()
            c = s[0]
            if s == "\\ No newline at end of file\n":
                fix_newline(hunk, a, b)
                continue
            if c == "\n":
                # Some patches may be missing the control char
                # on empty lines. Supply a leading space.
                s = " \n"
            hunk.append(s)
            if c == "+":
                b.append(s[1:])
            elif c == "-":
                a.append(s)
            else:
                b.append(s[1:])
                a.append(s)
    return 0

def fix_newline(hunk, a, b):
    l = hunk[-1]
    # tolerate CRLF in last line
    if l.endswith('\r\n'):
        hline = l[:-2]
    else:
        hline = l[:-1]
    c = hline[0]

    if c in " +":
        b[-1] = hline[1:]
    if c in " -":
        a[-1] = hline
    hunk[-1] = hline
    return 0


def testhunk(a, b, bstart):
    alen = len(a)
    blen = len(b)
    if alen > blen - bstart:
        return -1
    for i in xrange(alen):
        if a[i][1:] != b[i + bstart]:
            return -1
    return 0