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.
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ echo y > y
$ echo z > z
$ hg commit -qAm xy
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow
# status
$ clearcache
$ echo xx > x
$ echo yy > y
$ touch a
$ hg status
M x
M y
? a
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg add a
$ hg status
M x
M y
A a
# diff
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg add a
$ clearcache
$ hg diff
diff -r f3d0bb0d1e48 x
--- a/x* (glob)
+++ b/x* (glob)
@@ -1,1 +1,1 @@
-x
+xx
diff -r f3d0bb0d1e48 y
--- a/y* (glob)
+++ b/y* (glob)
@@ -1,1 +1,1 @@
-y
+yy
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# local commit
$ clearcache
$ echo a > a
$ echo xxx > x
$ echo yyy > y
$ hg commit -m a
? files fetched over 1 fetches - (? misses, 0.00% hit ratio) over *s (glob)
# local commit where the dirstate is clean -- ensure that we do just one fetch
# (update to a commit on the server first)
$ hg --config debug.dirstate.delaywrite=1 up 0
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ clearcache
$ hg debugdirstate
n 644 2 * x (glob)
n 644 2 * y (glob)
n 644 2 * z (glob)
$ echo xxxx > x
$ echo yyyy > y
$ hg commit -m x
created new head
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
# restore state for future tests
$ hg -q strip .
$ hg -q up tip
# rebase
$ clearcache
$ cd ../master
$ echo w > w
$ hg commit -qAm w
$ cd ../shallow
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 0 changes to 0 files (+1 heads)
new changesets fed61014d323
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg rebase -d tip
rebasing 1:9abfe7bca547 "a"
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/9abfe7bca547-8b11e5ff-rebase.hg (glob)
3 files fetched over 2 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# strip
$ clearcache
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg strip -r .
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/19edf50f4de7-df3d0f74-backup.hg (glob)
3 files fetched over 2 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
# unbundle
$ clearcache
$ ls -A
.hg
w
x
y
z
$ hg debugrebuilddirstate # fixes dirstate non-determinism
$ hg unbundle .hg/strip-backup/19edf50f4de7-df3d0f74-backup.hg
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
new changesets 19edf50f4de7 (1 drafts)
(run 'hg update' to get a working copy)
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ hg up
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cat a
a
# revert
$ clearcache
$ hg revert -r .~2 y z
no changes needed to z
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ hg checkout -C -r . -q
# explicit bundle should produce full bundle file
$ hg bundle -r 2 --base 1 ../local.bundle
1 changesets found
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow2 -q
2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow2
$ hg unbundle ../local.bundle
adding changesets
adding manifests
adding file changes
added 1 changesets with 3 changes to 3 files
new changesets 19edf50f4de7 (1 drafts)
(run 'hg update' to get a working copy)
$ hg log -r 2 --stat
changeset: 2:19edf50f4de7
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
a | 1 +
x | 2 +-
y | 2 +-
3 files changed, 3 insertions(+), 2 deletions(-)
# Merge
$ echo merge >> w
$ hg commit -m w
created new head
$ hg merge 2
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m merge
$ hg strip -q -r ".^"
# commit without producing new node
$ cd $TESTTMP
$ hgcloneshallow ssh://user@dummy/master shallow3 -q
$ cd shallow3
$ echo 1 > A
$ hg commit -m foo -A A
$ hg log -r . -T '{node}\n'
383ce605500277f879b7460a16ba620eb6930b7f
$ hg update -r '.^' -q
$ echo 1 > A
$ hg commit -m foo -A A
warning: commit already existed in the repository!
$ hg log -r . -T '{node}\n'
383ce605500277f879b7460a16ba620eb6930b7f