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 for the full copytracing algorithm
=======================================
Initial Setup
=============
use git diff to see rename
$ cat << EOF >> $HGRCPATH
> [diff]
> git=yes
> EOF
Setup an history where one side copy and rename a file (and update it) while the other side update it.
$ hg init t
$ cd t
$ echo 1 > a
$ hg ci -qAm "first"
$ hg cp a b
$ hg mv a c
$ echo 2 >> b
$ echo 2 >> c
$ hg ci -qAm "second"
$ hg co -C 0
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo 0 > a
$ echo 1 >> a
$ hg ci -qAm "other"
$ hg log -G --patch
@ changeset: 2:add3f11052fa
| tag: tip
| parent: 0:b8bf91eeebbc
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: other
|
| diff --git a/a b/a
| --- a/a
| +++ b/a
| @@ -1,1 +1,2 @@
| +0
| 1
|
| o changeset: 1:17c05bb7fcb6
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: second
|
| diff --git a/a b/b
| rename from a
| rename to b
| --- a/a
| +++ b/b
| @@ -1,1 +1,2 @@
| 1
| +2
| diff --git a/a b/c
| copy from a
| copy to c
| --- a/a
| +++ b/c
| @@ -1,1 +1,2 @@
| 1
| +2
|
o changeset: 0:b8bf91eeebbc
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: first
diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,1 @@
+1
Test Simple Merge
=================
$ hg merge --debug
unmatched files in other:
b
c
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
on remote side:
src: 'a' -> dst: 'b' *
src: 'a' -> dst: 'c' *
checking for directory renames
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: b8bf91eeebbc, local: add3f11052fa+, remote: 17c05bb7fcb6
starting 4 threads for background file closing (?)
preserving a for resolve of b
preserving a for resolve of c
removing a
b: remote moved from a -> m
picked tool ':merge' for b (binary False symlink False changedelete False)
merging a and b to b
my b@add3f11052fa+ other b@17c05bb7fcb6 ancestor a@b8bf91eeebbc
premerge successful
c: remote moved from a -> m
picked tool ':merge' for c (binary False symlink False changedelete False)
merging a and c to c
my c@add3f11052fa+ other c@17c05bb7fcb6 ancestor a@b8bf91eeebbc
premerge successful
0 files updated, 2 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
file b
$ cat b
0
1
2
file c
$ cat c
0
1
2
Test disabling copy tracing
===========================
first verify copy metadata was kept
-----------------------------------
$ hg up -qC 2
$ hg rebase --keep -d 1 -b 2 --config extensions.rebase=
rebasing 2:add3f11052fa tip "other"
merging b and a to b
merging c and a to c
$ cat b
0
1
2
next verify copy metadata is lost when disabled
------------------------------------------------
$ hg strip -r . --config extensions.strip=
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/t/.hg/strip-backup/550bd84c0cd3-fc575957-backup.hg
$ hg up -qC 2
$ hg rebase --keep -d 1 -b 2 --config extensions.rebase= --config experimental.copytrace=off --config ui.interactive=True << EOF
> c
> EOF
rebasing 2:add3f11052fa tip "other"
file 'a' was deleted in local [dest] but was modified in other [source].
You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
What do you want to do? c
$ cat b
1
2
$ cd ..
Verify disabling copy tracing still keeps copies from rebase source
-------------------------------------------------------------------
$ hg init copydisable
$ cd copydisable
$ touch a
$ hg ci -Aqm 'add a'
$ touch b
$ hg ci -Aqm 'add b, c'
$ hg cp b x
$ echo x >> x
$ hg ci -qm 'copy b->x'
$ hg up -q 1
$ touch z
$ hg ci -Aqm 'add z'
$ hg log -G -T '{rev} {desc}\n'
@ 3 add z
|
| o 2 copy b->x
|/
o 1 add b, c
|
o 0 add a
$ hg rebase -d . -b 2 --config extensions.rebase= --config experimental.copytrace=off
rebasing 2:6adcf8c12e7d "copy b->x"
saved backup bundle to $TESTTMP/copydisable/.hg/strip-backup/6adcf8c12e7d-ce4b3e75-rebase.hg
$ hg up -q 3
$ hg log -f x -T '{rev} {desc}\n'
3 copy b->x
1 add b, c
$ cd ../
test storage preservation
-------------------------
Verify rebase do not discard recorded copies data when copy tracing usage is
disabled.
Setup
$ hg init copydisable3
$ cd copydisable3
$ touch a
$ hg ci -Aqm 'add a'
$ hg cp a b
$ hg ci -Aqm 'copy a->b'
$ hg mv b c
$ hg ci -Aqm 'move b->c'
$ hg up -q 0
$ hg cp a b
$ echo b >> b
$ hg ci -Aqm 'copy a->b (2)'
$ hg log -G -T '{rev} {desc}\n'
@ 3 copy a->b (2)
|
| o 2 move b->c
| |
| o 1 copy a->b
|/
o 0 add a
Actual Test
A file is copied on one side and has been moved twice on the other side. the
file is copied from `0:a`, so the file history of the `3:b` should trace directly to `0:a`.
$ hg rebase -d 2 -s 3 --config extensions.rebase= --config experimental.copytrace=off
rebasing 3:47e1a9e6273b tip "copy a->b (2)"
saved backup bundle to $TESTTMP/copydisable3/.hg/strip-backup/47e1a9e6273b-2d099c59-rebase.hg
$ hg log -G -f b
@ changeset: 3:76024fb4b05b
: tag: tip
: user: test
: date: Thu Jan 01 00:00:00 1970 +0000
: summary: copy a->b (2)
:
o changeset: 0:ac82d8b1f7c4
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a