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 svn svn-bindings
$ cat >> $HGRCPATH <<EOF
> [extensions]
> convert =
> EOF
$ svnadmin create svn-repo
$ svnadmin load -q svn-repo < "$TESTDIR/svn/branches.svndump"
Convert trunk and branches
$ cat > branchmap <<EOF
> old3 newbranch
>
>
> EOF
$ hg convert --branchmap=branchmap --datesort -r 10 svn-repo A-hg
initializing destination A-hg repository
scanning source...
sorting...
converting...
10 init projA
9 hello
8 branch trunk, remove c and dir
7 change a
6 change b
5 move and update c
4 move and update c
3 change b again
2 move to old2
1 move back to old
0 last change to a
Test template keywords
$ hg -R A-hg log --template '{rev} {svnuuid}{svnpath}@{svnrev}\n'
10 644ede6c-2b81-4367-9dc8-d786514f2cde/trunk@10
9 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old@9
8 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old2@8
7 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old@7
6 644ede6c-2b81-4367-9dc8-d786514f2cde/trunk@6
5 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old@6
4 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old@5
3 644ede6c-2b81-4367-9dc8-d786514f2cde/trunk@4
2 644ede6c-2b81-4367-9dc8-d786514f2cde/branches/old@3
1 644ede6c-2b81-4367-9dc8-d786514f2cde/trunk@2
0 644ede6c-2b81-4367-9dc8-d786514f2cde/trunk@1
Convert again
$ hg convert --branchmap=branchmap --datesort svn-repo A-hg
scanning source...
sorting...
converting...
0 branch trunk@1 into old3
$ cd A-hg
$ hg log -G --template 'branch={branches} {rev} {desc|firstline} files: {files}\n'
o branch=newbranch 11 branch trunk@1 into old3 files:
|
| o branch= 10 last change to a files: a
| |
| | o branch=old 9 move back to old files:
| | |
| | o branch=old2 8 move to old2 files:
| | |
| | o branch=old 7 change b again files: b
| | |
| o | branch= 6 move and update c files: b
| | |
| | o branch=old 5 move and update c files: c
| | |
| | o branch=old 4 change b files: b
| | |
| o | branch= 3 change a files: a
| | |
| | o branch=old 2 branch trunk, remove c and dir files: c
| |/
| o branch= 1 hello files: a b c dir/e
|/
o branch= 0 init projA files:
$ hg branches
newbranch 11:a6d7cc050ad1
default 10:6e2b33404495
old 9:1b494af68c0b
old2 8:5be40b8dcbf6 (inactive)
$ hg tags -q
tip
$ cd ..
Test hg failing to call itself
$ HG=foobar hg convert svn-repo B-hg 2>&1 | grep abort
abort: Mercurial failed to run itself, check hg executable is in PATH
Convert 'trunk' to branch other than 'default'
$ cat > branchmap <<EOF
> default hgtrunk
>
>
> EOF
$ hg convert --branchmap=branchmap --datesort -r 10 svn-repo C-hg
initializing destination C-hg repository
scanning source...
sorting...
converting...
10 init projA
9 hello
8 branch trunk, remove c and dir
7 change a
6 change b
5 move and update c
4 move and update c
3 change b again
2 move to old2
1 move back to old
0 last change to a
$ cd C-hg
$ hg branches --template '{branch}\n'
hgtrunk
old
old2
$ cd ..