view mercurial/diffhelper.py @ 42897:d7304434390f

changegroup: move message about added changes to transaction summary

Before that, applying multiple changegroups in the same transaction issued the
message multiple time. This result in a confusing output:

    adding changesets
    adding manifests
    adding file changes
    added 32768 changesets with 60829 changes to 2668 files
    adding changesets
    adding manifests
    adding file changes
    added 8192 changesets with 16885 changes to 1553 files
    adding changesets
    adding manifests
    adding file changes
    added 1020 changesets with 1799 changes to 536 files
    adding changesets
    adding manifests
    ...

Instead, we now only issue the message once at the end of the transaction,
summing up all added changesets, changes and files. The line is identical, but
happens sightly later in the output.

There are other suboptimal behavior around issue multiple changegroup (eg:
progress bar). We'll cover them later.

This impact of lot of test as one would expect, but a two pass check show they
are just the order change we expected.

To deal with "under the hood" bundle application by internal code, we had to
take a slightly hacky move. We could clean that up with a more official way to
enter "under the hood" section, however I want to keep this series simple to get
it landed. This kind of change have a very high bit rot rate since it impact a
lot of test output.

# diffhelper.py - helper routines for patch
#
# Copyright 2009 Matt Mackall <[e-mail]> 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

from .i18n import _

from . import (
    error,
    pycompat,
)

def addlines(fp, hunk, lena, lenb, a, b):
    """Read lines from fp into the hunk

    The hunk is parsed into two arrays, a and b. a gets the old state of
    the text, b gets the new state. The control char from the hunk is saved
    when inserting into a, but not b (for performance while deleting files.)
    """
    while True:
        todoa = lena - len(a)
        todob = lenb - len(b)
        num = max(todoa, todob)
        if num == 0:
            break
        for i in pycompat.xrange(num):
            s = fp.readline()
            if not s:
                raise error.ParseError(_('incomplete hunk'))
            if s == "\\ No newline at end of file\n":
                fixnewline(hunk, a, b)
                continue
            if s == '\n' or s == '\r\n':
                # Some patches may be missing the control char
                # on empty lines. Supply a leading space.
                s = ' ' + s
            hunk.append(s)
            if s.startswith('+'):
                b.append(s[1:])
            elif s.startswith('-'):
                a.append(s)
            else:
                b.append(s[1:])
                a.append(s)

def fixnewline(hunk, a, b):
    """Fix up the last lines of a and b when the patch has no newline at EOF"""
    l = hunk[-1]
    # tolerate CRLF in last line
    if l.endswith('\r\n'):
        hline = l[:-2]
    else:
        hline = l[:-1]

    if hline.startswith((' ', '+')):
        b[-1] = hline[1:]
    if hline.startswith((' ', '-')):
        a[-1] = hline
    hunk[-1] = hline

def testhunk(a, b, bstart):
    """Compare the lines in a with the lines in b

    a is assumed to have a control char at the start of each line, this char
    is ignored in the compare.
    """
    alen = len(a)
    blen = len(b)
    if alen > blen - bstart or bstart < 0:
        return False
    for i in pycompat.xrange(alen):
        if a[i][1:] != b[i + bstart]:
            return False
    return True