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Differential D10001

patch: make diff --git to differentiate b/w file is empty or doesn't exists
ClosedPublic

Authored by khanchi97 on Feb 16 2021, 5:26 AM.

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rHG33350debb480: patch: make diff --git to differentiate b/w file is empty or doesn't exists
Summary

Before this patch, as we didn't differentiate the two cases of a file in a context:

  1. File doesn't exists
  2. File is empty

which causes the blob id to be same for both the cases.

Now we use nullhex for a file which doesn't exists in a context (aligning it with
the git diff format)

Changes in test file reflect the fixed behavior.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

khanchi97 created this revision.Feb 16 2021, 5:26 AM
khanchi97 added a commit: rHG33350debb480: patch: make diff --git to differentiate b/w file is empty or doesn't exists.Feb 24 2021, 11:07 AM
This revision was not accepted when it landed; it landed in state Needs Review.
Closed by commit rHG33350debb480: patch: make diff --git to differentiate b/w file is empty or doesn't exists (authored by khanchi97). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/patch.py (9 lines)
Mtests/test-diff-unified.t (4 lines)

Diff 25867

mercurial/patch.py

import os import os
import re import re
import shutil import shutil
import zlib import zlib
from .i18n import _ from .i18n import _
from .node import ( from .node import (
hex, hex,
nullhex,
short, short,
) )
from .pycompat import open from .pycompat import open
from . import ( from . import (
copies, copies,
diffhelper, diffhelper,
diffutil, diffutil,
encoding, encoding,
opts: user passed options opts: user passed options
It exists as a separate function so that extensions like extdiff can wrap It exists as a separate function so that extensions like extdiff can wrap
it and use the file content directly. it and use the file content directly.
""" """
ctx1, fctx1, path1, flag1, content1, date1 = data1 ctx1, fctx1, path1, flag1, content1, date1 = data1
ctx2, fctx2, path2, flag2, content2, date2 = data2 ctx2, fctx2, path2, flag2, content2, date2 = data2
index1 = _gitindex(content1) if path1 in ctx1 else nullhex
index2 = _gitindex(content2) if path2 in ctx2 else nullhex
if binary and opts.git and not opts.nobinary: if binary and opts.git and not opts.nobinary:
text = mdiff.b85diff(content1, content2) text = mdiff.b85diff(content1, content2)
if text: if text:
header.append( header.append(
b'index %s..%s' % (_gitindex(content1), _gitindex(content2)) b'index %s..%s' % (index1, index2)
) )
hunks = ((None, [text]),) hunks = ((None, [text]),)
else: else:
if opts.git and opts.index > 0: if opts.git and opts.index > 0:
flag = flag1 flag = flag1
if flag is None: if flag is None:
flag = flag2 flag = flag2
header.append( header.append(
b'index %s..%s %s' b'index %s..%s %s'
% ( % (
_gitindex(content1)[0 : opts.index], index1[0 : opts.index],
_gitindex(content2)[0 : opts.index], index2[0 : opts.index],
_gitmode[flag], _gitmode[flag],
) )
) )
uheaders, hunks = mdiff.unidiff( uheaders, hunks = mdiff.unidiff(
content1, content1,
date1, date1,
content2, content2,

tests/test-diff-unified.t

$ hg init bloboids $ hg init bloboids
$ cd bloboids $ cd bloboids
$ touch a $ touch a
$ hg ci -Am "empty a" $ hg ci -Am "empty a"
adding a adding a
$ hg diff -c 0 --git --config experimental.extendedheader.index=full | grep index $ hg diff -c 0 --git --config experimental.extendedheader.index=full | grep index
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 100644 index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 100644
Make sure `hg diff --git` differentiate "file was empty" and "file is removed" Make sure `hg diff --git` differentiate "file was empty" and "file is removed"
for git blob oids for git blob oids
$ rm a $ rm a
$ hg ci -Am "removed a" $ hg ci -Am "removed a"
removing a removing a
$ hg diff -c 1 --git --config experimental.extendedheader.index=full | grep index $ hg diff -c 1 --git --config experimental.extendedheader.index=full | grep index
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 100644 index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..0000000000000000000000000000000000000000 100644
$ cd .. $ cd ..