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.
Setup extension:
$ cat <<EOF >> $HGRCPATH
> [extensions]
> mq =
> [mq]
> git = keep
> EOF
Test merge with mq changeset as the second parent:
$ hg init m
$ cd m
$ touch a b c
$ hg add a
$ hg commit -m a
$ hg add b
$ hg qnew -d "0 0" b
$ hg update 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg add c
$ hg commit -m c
created new head
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m merge
abort: cannot commit over an applied mq patch
[255]
$ cd ..
Issue529: mq aborts when merging patch deleting files
$ checkundo()
> {
> if [ -f .hg/store/undo ]; then
> echo ".hg/store/undo still exists"
> fi
> }
Commit two dummy files in "init" changeset:
$ hg init t
$ cd t
$ echo a > a
$ echo b > b
$ hg ci -Am init
adding a
adding b
$ hg tag -l init
Create a patch removing a:
$ hg qnew rm_a
$ hg rm a
$ hg qrefresh -m "rm a"
Save the patch queue so we can merge it later:
$ hg qsave -c -e
copy $TESTTMP/t/.hg/patches to $TESTTMP/t/.hg/patches.1
$ checkundo
Update b and commit in an "update" changeset:
$ hg up -C init
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo b >> b
$ hg st
M b
$ hg ci -m update
created new head
# Here, qpush used to abort with :
# The system cannot find the file specified => a
$ hg manifest
a
b
$ hg qpush -a -m
merging with queue at: $TESTTMP/t/.hg/patches.1
applying rm_a
now at: rm_a
$ checkundo
$ hg manifest
b
Ensure status is correct after merge:
$ hg qpop -a
popping rm_a
popping .hg.patches.merge.marker
patch queue now empty
$ cd ..
Classic MQ merge sequence *with an explicit named queue*:
$ hg init t2
$ cd t2
$ echo '[diff]' > .hg/hgrc
$ echo 'nodates = 1' >> .hg/hgrc
$ echo a > a
$ hg ci -Am init
adding a
$ echo b > a
$ hg ci -m changea
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg cp a aa
$ echo c >> a
$ hg qnew --git -f -e patcha
$ echo d >> a
$ hg qnew -d '0 0' -f -e patcha2
Create the reference queue:
$ hg qsave -c -e -n refqueue
copy $TESTTMP/t2/.hg/patches to $TESTTMP/t2/.hg/refqueue
$ hg up -C 1
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
Merge:
$ HGMERGE=internal:other hg qpush -a -m -n refqueue
merging with queue at: $TESTTMP/t2/.hg/refqueue
applying patcha
patching file a
Hunk #1 succeeded at 2 with fuzz 1 (offset 0 lines).
fuzz found when applying patch, stopping
patch didn't work out, merging patcha
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
0 files updated, 2 files merged, 0 files removed, 0 files unresolved
applying patcha2
now at: patcha2
Check patcha is still a git patch:
$ cat .hg/patches/patcha
# HG changeset patch
# Parent d3873e73d99ef67873dac33fbcc66268d5d2b6f4
diff --git a/a b/a
--- a/a
+++ b/a
@@ -1,1 +1,2 @@
-b
+a
+c
diff --git a/a b/aa
copy from a
copy to aa
--- a/a
+++ b/aa
@@ -1,1 +1,1 @@
-b
+a
Check patcha2 is still a regular patch:
$ cat .hg/patches/patcha2
# HG changeset patch
# Date 0 0
# Parent ???????????????????????????????????????? (glob)
diff -r ???????????? -r ???????????? a (glob)
--- a/a
+++ b/a
@@ -1,2 +1,3 @@
a
c
+d
$ cd ..