repoview: add caching bits
Add a caching infrastructure to cache hidden changesets. The cache tries to read
the cache lazily and falls back to recomputing if no wlock can be obtain.
To validate the cache we store a sha of the obstore content and repo heads in
the beginning of the cache which we check every request.
Test applying context diffs
$ cat > writepatterns.py <<EOF
> import sys
>
> path = sys.argv[1]
> lasteol = sys.argv[2] == '1'
> patterns = sys.argv[3:]
>
> fp = file(path, 'wb')
> for i, pattern in enumerate(patterns):
> count = int(pattern[0:-1])
> char = pattern[-1] + '\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
> sys.stdout.write(repr(file(sys.argv[1], 'rb').read()) + '\n')
> 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 ..