procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
===============================
Test the "tracked hint" feature
===============================
The tracked hint feature provide a file that get updated when the set of tracked
files get updated.
basic setup
$ cat << EOF >> $HGRCPATH
> [format]
> use-dirstate-tracked-hint=yes
> EOF
$ hg init tracked-hint-test
$ cd tracked-hint-test
$ hg debugbuilddag '.+10' -n
$ hg log -G -T '{rev} {desc} {files}\n'
o 10 r10 nf10
|
o 9 r9 nf9
|
o 8 r8 nf8
|
o 7 r7 nf7
|
o 6 r6 nf6
|
o 5 r5 nf5
|
o 4 r4 nf4
|
o 3 r3 nf3
|
o 2 r2 nf2
|
o 1 r1 nf1
|
o 0 r0 nf0
$ hg up tip
11 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg files
nf0
nf1
nf10
nf2
nf3
nf4
nf5
nf6
nf7
nf8
nf9
key-file exists
-----------
The tracked hint file should exist
$ ls -1 .hg/dirstate*
.hg/dirstate
.hg/dirstate-tracked-hint
key-file stay the same if the tracked set is unchanged
------------------------------------------------------
(copy its content for later comparison)
$ cp .hg/dirstate-tracked-hint ../key-bck
$ echo foo >> nf0
$ sleep 1
$ hg status
M nf0
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
$ hg revert -C nf0
$ sleep 1
$ hg status
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
key-file change if the tracked set is changed manually
------------------------------------------------------
adding a file to tracking
$ cp .hg/dirstate-tracked-hint ../key-bck
$ echo x > x
$ hg add x
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
remove a file from tracking
(forget)
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg forget x
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
(remove)
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg remove nf1
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
key-file changes on revert (when applicable)
--------------------------------------------
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg status
R nf1
? x
$ hg revert --all
undeleting nf1
$ hg status
? x
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
`hg update` does affect the key-file (when needed)
--------------------------------------------------
update changing the tracked set
(removing)
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg status --rev . --rev '.#generations[-1]'
R nf10
$ hg up '.#generations[-1]'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
(adding)
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg status --rev . --rev '.#generations[1]'
A nf10
$ hg up '.#generations[1]'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Files .hg/dirstate-tracked-hint and ../key-bck differ
[1]
update not affecting the tracked set
$ echo foo >> nf0
$ hg commit -m foo
$ cp .hg/dirstate-tracked-hint ../key-bck
$ hg status --rev . --rev '.#generations[-1]'
M nf0
$ hg up '.#generations[-1]'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ diff --brief .hg/dirstate-tracked-hint ../key-bck
Test upgrade and downgrade
==========================
$ ls .hg/dirstate-tracked-hint
.hg/dirstate-tracked-hint
$ hg debugrequires | grep 'tracked'
dirstate-tracked-key-v1
downgrade
$ hg debugupgraderepo --config format.use-dirstate-tracked-hint=no --run --quiet
upgrade will perform the following actions:
requirements
preserved: * (glob)
removed: dirstate-tracked-key-v1
no revlogs to process
$ ls -1 .hg/dirstate-tracked-hint
ls: *.hg/dirstate-tracked-hint*: $ENOENT$ (glob)
[2]
$ hg debugrequires | grep 'tracked'
[1]
upgrade
$ hg debugupgraderepo --config format.use-dirstate-tracked-hint=yes --run --quiet
upgrade will perform the following actions:
requirements
preserved: * (glob)
added: dirstate-tracked-key-v1
no revlogs to process
$ ls -1 .hg/dirstate-tracked-hint
.hg/dirstate-tracked-hint
$ hg debugrequires | grep 'tracked'
dirstate-tracked-key-v1
$ cd ..
Test automatic upgrade and downgrade
------------------------------------
create an initial repository
$ hg init auto-upgrade \
> --config format.use-dirstate-tracked-hint=no
$ hg debugbuilddag -R auto-upgrade --new-file .+5
$ hg -R auto-upgrade update
6 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg debugformat -R auto-upgrade | grep tracked
tracked-hint: no
upgrade it to dirstate-tracked-hint automatically
$ hg status -R auto-upgrade \
> --config format.use-dirstate-tracked-hint.automatic-upgrade-of-mismatching-repositories=yes \
> --config format.use-dirstate-tracked-hint=yes
automatically upgrading repository to the `tracked-hint` feature
(see `hg help config.format.use-dirstate-tracked-hint` for details)
$ hg debugformat -R auto-upgrade | grep tracked
tracked-hint: yes
downgrade it from dirstate-tracked-hint automatically
$ hg status -R auto-upgrade \
> --config format.use-dirstate-tracked-hint.automatic-upgrade-of-mismatching-repositories=yes \
> --config format.use-dirstate-tracked-hint=no
automatically downgrading repository from the `tracked-hint` feature
(see `hg help config.format.use-dirstate-tracked-hint` for details)
$ hg debugformat -R auto-upgrade | grep tracked
tracked-hint: no