mercurial/pure/diffhelpers.py
author Matt Mackall <mpm@selenic.com>
Fri, 03 Apr 2009 14:51:48 -0500
changeset 7948 de377b1a9a84
parent 7702 f6bb40554e34
child 8225 46293a0c7e9f
permissions -rw-r--r--
move encoding bits from util to encoding In addition to cleaning up util, this gets rid of some circular dependencies.

# 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, incorporated herein by reference.

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]
    c = l[0]
    hline = l[:-1]

    if c == " " or c == "+":
        b[-1] = l[1:-1]
    if c == " " or c == "-":
        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