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.
#testcases obsstore-off obsstore-on
$ cat << EOF >> $HGRCPATH
> [extensions]
> amend =
> EOF
#if obsstore-on
$ cat << EOF >> $HGRCPATH
> [experimental]
> evolution.createmarkers = True
> EOF
#endif
Prepare parent repo
-------------------
$ hg init r
$ cd r
$ echo a > a
$ hg ci -Am0
adding a
Link first subrepo
------------------
$ echo 's = s' >> .hgsub
$ hg add .hgsub
$ hg init s
amend without .hgsub
$ hg amend s
abort: can't commit subrepos without .hgsub
[255]
amend with subrepo
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
A .hgsub
A .hgsubstate
A a
$ cat .hgsubstate
0000000000000000000000000000000000000000 s
Update subrepo
--------------
add new commit to be amended
$ echo a >> a
$ hg ci -m1
amend with dirty subrepo
$ echo a >> s/a
$ hg add -R s
adding s/a
$ hg amend
abort: uncommitted changes in subrepository "s"
(use --subrepos for recursive commit)
[255]
amend with modified subrepo
$ hg ci -R s -m0
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
M .hgsubstate
M a
$ cat .hgsubstate
f7b1eb17ad24730a1651fccd46c43826d1bbc2ac s
revert subrepo change
$ hg up -R s -q null
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
M a
Link another subrepo
--------------------
add new commit to be amended
$ echo b >> b
$ hg ci -qAm2
also checks if non-subrepo change is included
$ echo a >> a
amend with another subrepo
$ hg init t
$ echo b >> t/b
$ hg ci -R t -Am0
adding b
$ echo 't = t' >> .hgsub
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
M .hgsub
M .hgsubstate
M a
A b
$ cat .hgsubstate
0000000000000000000000000000000000000000 s
bfb1a4fb358498a9533dabf4f2043d94162f1fcd t
Unlink one subrepo
------------------
add new commit to be amended
$ echo a >> a
$ hg ci -m3
$ echo 't = t' > .hgsub
--interactive won't silently ignore dirty subrepos
$ echo modified > t/b
$ hg amend --interactive --config ui.interactive=True
abort: uncommitted changes in subrepository "t"
[255]
$ hg amend --interactive --config ui.interactive=True --config ui.commitsubrepos=True
abort: uncommitted changes in subrepository "t"
[255]
$ hg -R t revert -q --all --no-backup
amend with one subrepo dropped
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
M .hgsub
M .hgsubstate
M a
$ cat .hgsubstate
bfb1a4fb358498a9533dabf4f2043d94162f1fcd t
Unlink subrepos completely
--------------------------
add new commit to be amended
$ echo a >> a
$ hg ci -m3
amend with .hgsub removed
$ hg rm .hgsub
$ hg amend
saved backup bundle to * (glob) (obsstore-off !)
$ hg status --change .
M a
R .hgsub
R .hgsubstate
broken repositories will refuse to push
#if obsstore-off
$ hg up -q -C 2
#else
$ hg up -q -C 6
#endif
$ echo c >> t/b
$ hg amend -q -R t
$ hg init ../dest
$ hg init ../dest/t
$ hg init ../dest/s
$ hg push -q ../dest
abort: subrepo 't' is hidden in revision 04aa62396ec6 (obsstore-on !)
abort: subrepo 't' not found in revision 04aa62396ec6 (obsstore-off !)
[255]
... unless forced
$ hg push --force -q ../dest
$ hg verify -R ../dest
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 5 changesets with 12 changes to 4 files
checking subrepo links
subrepo 't' not found in revision 04aa62396ec6
subrepo 't' not found in revision 6bce99600681
$ cd ..