dirstate-v2: no longer register the data-file during transaction
If the data file change during the transaction, we cannot truncate it.
The content of the file itself is fine as it will get backed up at the same time
as the docket.
Leaving the trailing data at the end of failed transaction is fine. The
dirstate-v2 format supports it. The dead data will simply we written over if
necessary.
$ hg init repo
$ cd repo
$ touch a.html b.html c.py d.py
$ cat > frontend.sparse << EOF
> [include]
> *.html
> EOF
$ hg -q commit -A -m initial
$ echo 1 > a.html
$ echo 1 > c.py
$ hg commit -m 'commit 1'
Enable sparse profile
$ hg debugrequires
dotencode
dirstate-v2 (dirstate-v2 !)
fncache
generaldelta
persistent-nodemap (rust !)
revlog-compression-zstd (zstd !)
revlogv1
share-safe
sparserevlog
store
testonly-simplestore (reposimplestore !)
$ hg debugsparse --config extensions.sparse= --enable-profile frontend.sparse
$ ls -A
.hg
a.html
b.html
Requirement for sparse added when sparse is enabled
$ hg debugrequires --config extensions.sparse=
dotencode
dirstate-v2 (dirstate-v2 !)
exp-sparse
fncache
generaldelta
persistent-nodemap (rust !)
revlog-compression-zstd (zstd !)
revlogv1
share-safe
sparserevlog
store
testonly-simplestore (reposimplestore !)
Client without sparse enabled reacts properly
$ hg files
abort: repository is using sparse feature but sparse is not enabled; enable the "sparse" extensions to access
[255]
Requirement for sparse is removed when sparse is disabled
$ hg debugsparse --reset --config extensions.sparse=
$ hg debugrequires
dotencode
dirstate-v2 (dirstate-v2 !)
fncache
generaldelta
persistent-nodemap (rust !)
revlog-compression-zstd (zstd !)
revlogv1
share-safe
sparserevlog
store
testonly-simplestore (reposimplestore !)
And client without sparse can access
$ hg files
a.html
b.html
c.py
d.py
frontend.sparse