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.
$ hg init rep; cd rep
$ touch empty-file
$ "$PYTHON" -c 'for x in range(10000): print(x)' > large-file
$ hg addremove
adding empty-file
adding large-file
$ hg commit -m A
$ rm large-file empty-file
$ "$PYTHON" -c 'for x in range(10,10000): print(x)' > another-file
$ hg addremove -s50
adding another-file
removing empty-file
removing large-file
recording removal of large-file as rename to another-file (99% similar)
$ hg commit -m B
comparing two empty files caused ZeroDivisionError in the past
$ hg update -C 0
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ rm empty-file
$ touch another-empty-file
$ hg addremove -s50
adding another-empty-file
removing empty-file
$ cd ..
$ hg init rep2; cd rep2
$ "$PYTHON" -c 'for x in range(10000): print(x)' > large-file
$ "$PYTHON" -c 'for x in range(50): print(x)' > tiny-file
$ hg addremove
adding large-file
adding tiny-file
$ hg commit -m A
$ "$PYTHON" -c 'for x in range(70): print(x)' > small-file
$ rm tiny-file
$ rm large-file
$ hg addremove -s50
removing large-file
adding small-file
removing tiny-file
recording removal of tiny-file as rename to small-file (82% similar)
$ hg commit -m B
should be sorted by path for stable result
$ for i in `"$PYTHON" $TESTDIR/seq.py 0 9`; do
> cp small-file $i
> done
$ rm small-file
$ hg addremove
adding 0
adding 1
adding 2
adding 3
adding 4
adding 5
adding 6
adding 7
adding 8
adding 9
removing small-file
recording removal of small-file as rename to 0 (100% similar)
recording removal of small-file as rename to 1 (100% similar)
recording removal of small-file as rename to 2 (100% similar)
recording removal of small-file as rename to 3 (100% similar)
recording removal of small-file as rename to 4 (100% similar)
recording removal of small-file as rename to 5 (100% similar)
recording removal of small-file as rename to 6 (100% similar)
recording removal of small-file as rename to 7 (100% similar)
recording removal of small-file as rename to 8 (100% similar)
recording removal of small-file as rename to 9 (100% similar)
$ hg commit -m '10 same files'
pick one from many identical files
$ cp 0 a
$ rm `"$PYTHON" $TESTDIR/seq.py 0 9`
$ hg addremove
removing 0
removing 1
removing 2
removing 3
removing 4
removing 5
removing 6
removing 7
removing 8
removing 9
adding a
recording removal of 0 as rename to a (100% similar)
$ hg revert -aq
pick one from many similar files
$ cp 0 a
$ for i in `"$PYTHON" $TESTDIR/seq.py 0 9`; do
> echo $i >> $i
> done
$ hg commit -m 'make them slightly different'
$ rm `"$PYTHON" $TESTDIR/seq.py 0 9`
$ hg addremove -s50
removing 0
removing 1
removing 2
removing 3
removing 4
removing 5
removing 6
removing 7
removing 8
removing 9
adding a
recording removal of 0 as rename to a (99% similar)
$ hg commit -m 'always the same file should be selected'
should all fail
$ hg addremove -s foo
abort: similarity must be a number
[10]
$ hg addremove -s -1
abort: similarity must be between 0 and 100
[10]
$ hg addremove -s 1e6
abort: similarity must be between 0 and 100
[10]
$ cd ..
Issue1527: repeated addremove causes Abort
$ hg init rep3; cd rep3
$ mkdir d
$ echo a > d/a
$ hg add d/a
$ hg commit -m 1
$ mv d/a d/b
$ hg addremove -s80
removing d/a
adding d/b
recording removal of d/a as rename to d/b (100% similar)
$ hg debugstate
r 0 0 1970-01-01 00:00:00 d/a
a 0 -1 unset d/b
copy: d/a -> d/b
$ mv d/b c
no copies found here (since the target isn't in d
$ hg addremove -s80 d
removing d/b
copies here
$ hg addremove -s80
adding c
recording removal of d/a as rename to c (100% similar)
$ cd ..