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.
This test makes sure that we don't mark a file as merged with its ancestor
when we do a merge.
$ cat <<EOF > merge
> import sys, os
> print("merging for", os.path.basename(sys.argv[1]))
> EOF
$ HGMERGE="\"$PYTHON\" ../merge"; export HGMERGE
Creating base:
$ hg init a
$ cd a
$ echo 1 > foo
$ echo 1 > bar
$ echo 1 > baz
$ echo 1 > quux
$ hg add foo bar baz quux
$ hg commit -m "base"
$ cd ..
$ hg clone a b
updating to branch default
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
Creating branch a:
$ cd a
$ echo 2a > foo
$ echo 2a > bar
$ hg commit -m "branch a"
Creating branch b:
$ cd ..
$ cd b
$ echo 2b > foo
$ echo 2b > baz
$ hg commit -m "branch b"
We shouldn't have anything but n state here:
$ hg debugstate --no-dates | grep -v "^n"
[1]
Merging:
$ hg pull ../a
pulling from ../a
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 2 changes to 2 files (+1 heads)
new changesets bdd988058d16
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge -v
resolving manifests
getting bar
merging foo
merging for foo
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ echo 2m > foo
$ echo 2b > baz
$ echo new > quux
$ hg ci -m "merge"
main: we should have a merge here:
$ hg debugindex --changelog
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 cdca01651b96 000000000000 000000000000
1 1 f6718a9cb7f3 cdca01651b96 000000000000
2 2 bdd988058d16 cdca01651b96 000000000000
3 3 d8a521142a3c f6718a9cb7f3 bdd988058d16
log should show foo and quux changed:
$ hg log -v -r tip
changeset: 3:d8a521142a3c
tag: tip
parent: 1:f6718a9cb7f3
parent: 2:bdd988058d16
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: foo quux
description:
merge
foo: we should have a merge here:
$ hg debugindex foo
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 1 2ffeddde1b65 b8e02f643373 000000000000
2 2 33d1fb69067a b8e02f643373 000000000000
3 3 aa27919ee430 2ffeddde1b65 33d1fb69067a
bar: we should not have a merge here:
$ hg debugindex bar
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 2 33d1fb69067a b8e02f643373 000000000000
baz: we should not have a merge here:
$ hg debugindex baz
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 1 2ffeddde1b65 b8e02f643373 000000000000
quux: we should not have a merge here:
$ hg debugindex quux
rev linkrev nodeid p1-nodeid p2-nodeid
0 0 b8e02f643373 000000000000 000000000000
1 3 6128c0f33108 b8e02f643373 000000000000
Manifest entries should match tips of all files:
$ hg manifest --debug
33d1fb69067a0139622a3fa3b7ba1cdb1367972e 644 bar
2ffeddde1b65b4827f6746174a145474129fa2ce 644 baz
aa27919ee4303cfd575e1fb932dd64d75aa08be4 644 foo
6128c0f33108e8cfbb4e0824d13ae48b466d7280 644 quux
Everything should be clean now:
$ hg status
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 4 changesets with 10 changes to 4 files
$ cd ..