delta: skip "empty delta" optimisation for non-general case (issue6006)
Non-general delta repository cannot delta against anything than prev. So even if
the delta to prev is empty we should use it.
This is similar to the change made in bafa1c4bb7a8.
Differential Revision: https://phab.mercurial-scm.org/D5201
Test applying context diffs
$ cat > writepatterns.py <<EOF
> import sys
>
> path = sys.argv[1]
> lasteol = sys.argv[2] == '1'
> patterns = sys.argv[3:]
>
> fp = open(path, 'wb')
> for i, pattern in enumerate(patterns):
> count = int(pattern[0:-1])
> char = pattern[-1].encode('utf8') + b'\n'
> if not lasteol and i == len(patterns) - 1:
> fp.write((char*count)[:-1])
> else:
> fp.write(char*count)
> fp.close()
> EOF
$ cat > cat.py <<EOF
> import sys
> from mercurial import pycompat
> from mercurial.utils import stringutil
> pycompat.stdout.write(b'%s\n'
> % stringutil.pprint(open(sys.argv[1], 'rb').read()))
> EOF
Initialize the test repository
$ hg init repo
$ cd repo
$ "$PYTHON" ../writepatterns.py a 0 5A 1B 5C 1D
$ "$PYTHON" ../writepatterns.py b 1 1A 1B
$ "$PYTHON" ../writepatterns.py c 1 5A
$ "$PYTHON" ../writepatterns.py d 1 5A 1B
$ hg add
adding a
adding b
adding c
adding d
$ hg ci -m addfiles
Add file, missing a last end of line
$ hg import --no-commit - <<EOF
> *** /dev/null 2010-10-16 18:05:49.000000000 +0200
> --- b/newnoeol 2010-10-16 18:23:26.000000000 +0200
> ***************
> *** 0 ****
> --- 1,2 ----
> + a
> + b
> \ No newline at end of file
> *** a/a Sat Oct 16 16:35:51 2010
> --- b/a Sat Oct 16 16:35:51 2010
> ***************
> *** 3,12 ****
> A
> A
> A
> ! B
> C
> C
> C
> C
> C
> ! D
> \ No newline at end of file
> --- 3,13 ----
> A
> A
> A
> ! E
> C
> C
> C
> C
> C
> ! F
> ! F
>
> *** a/b 2010-10-16 18:40:38.000000000 +0200
> --- /dev/null 2010-10-16 18:05:49.000000000 +0200
> ***************
> *** 1,2 ****
> - A
> - B
> --- 0 ----
> *** a/c Sat Oct 16 21:34:26 2010
> --- b/c Sat Oct 16 21:34:27 2010
> ***************
> *** 3,5 ****
> --- 3,7 ----
> A
> A
> A
> + B
> + B
> *** a/d Sat Oct 16 21:47:20 2010
> --- b/d Sat Oct 16 21:47:22 2010
> ***************
> *** 2,6 ****
> A
> A
> A
> - A
> - B
> --- 2,4 ----
> EOF
applying patch from stdin
$ hg st
M a
M c
M d
A newnoeol
R b
What's in a
$ "$PYTHON" ../cat.py a
'A\nA\nA\nA\nA\nE\nC\nC\nC\nC\nC\nF\nF\n'
$ "$PYTHON" ../cat.py newnoeol
'a\nb'
$ "$PYTHON" ../cat.py c
'A\nA\nA\nA\nA\nB\nB\n'
$ "$PYTHON" ../cat.py d
'A\nA\nA\nA\n'
$ cd ..