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 interactions between mq and patch.eol
$ cat <<EOF >> $HGRCPATH
> [extensions]
> mq =
> [diff]
> nodates = 1
> EOF
$ cat > makepatch.py <<EOF
> f = open('eol.diff', 'wb')
> w = f.write
> w(b'test message\n')
> w(b'diff --git a/a b/a\n')
> w(b'--- a/a\n')
> w(b'+++ b/a\n')
> w(b'@@ -1,5 +1,5 @@\n')
> w(b' a\n')
> w(b'-b\r\n')
> w(b'+y\r\n')
> w(b' c\r\n')
> w(b' d\n')
> w(b'-e\n')
> w(b'\\\\ No newline at end of file\n')
> w(b'+z\r\n')
> w(b'\\\\ No newline at end of file\r\n')
> EOF
$ cat > cateol.py <<EOF
> import sys
> try:
> stdout = sys.stdout.buffer
> except AttributeError:
> stdout = sys.stdout
> for line in open(sys.argv[1], 'rb'):
> line = line.replace(b'\r', b'<CR>')
> line = line.replace(b'\n', b'<LF>')
> stdout.write(line + b'\n')
> EOF
$ hg init repo
$ cd repo
$ echo '\.diff' > .hgignore
$ echo '\.rej' >> .hgignore
Test different --eol values
$ "$PYTHON" -c 'open("a", "wb").write(b"a\nb\nc\nd\ne")'
$ hg ci -Am adda
adding .hgignore
adding a
$ "$PYTHON" ../makepatch.py
$ hg qimport eol.diff
adding eol.diff to series file
should fail in strict mode
$ hg qpush
applying eol.diff
patching file a
Hunk #1 FAILED at 0
1 out of 1 hunks FAILED -- saving rejects to file a.rej
patch failed, unable to continue (try -v)
patch failed, rejects left in working directory
errors during apply, please fix and qrefresh eol.diff
[2]
$ hg qpop
popping eol.diff
patch queue now empty
invalid eol
$ hg --config patch.eol='LFCR' qpush
applying eol.diff
patch failed, unable to continue (try -v)
patch failed, rejects left in working directory
errors during apply, please fix and qrefresh eol.diff
[2]
$ hg qpop
popping eol.diff
patch queue now empty
force LF
$ hg --config patch.eol='CRLF' qpush
applying eol.diff
now at: eol.diff
$ hg qrefresh
$ "$PYTHON" ../cateol.py .hg/patches/eol.diff
# HG changeset patch<LF>
# Parent 0d0bf99a8b7a3842c6f8ef09e34f69156c4bd9d0<LF>
test message<LF>
<LF>
diff -r 0d0bf99a8b7a a<LF>
--- a/a<LF>
+++ b/a<LF>
@@ -1,5 +1,5 @@<LF>
-a<LF>
-b<LF>
-c<LF>
-d<LF>
-e<LF>
\ No newline at end of file<LF>
+a<CR><LF>
+y<CR><LF>
+c<CR><LF>
+d<CR><LF>
+z<LF>
\ No newline at end of file<LF>
$ "$PYTHON" ../cateol.py a
a<CR><LF>
y<CR><LF>
c<CR><LF>
d<CR><LF>
z
$ hg qpop
popping eol.diff
patch queue now empty
push again forcing LF and compare revisions
$ hg --config patch.eol='CRLF' qpush
applying eol.diff
now at: eol.diff
$ "$PYTHON" ../cateol.py a
a<CR><LF>
y<CR><LF>
c<CR><LF>
d<CR><LF>
z
$ hg qpop
popping eol.diff
patch queue now empty
push again without LF and compare revisions
$ hg qpush
applying eol.diff
now at: eol.diff
$ "$PYTHON" ../cateol.py a
a<CR><LF>
y<CR><LF>
c<CR><LF>
d<CR><LF>
z
$ hg qpop
popping eol.diff
patch queue now empty
$ cd ..
Test .rej file EOL are left unchanged
$ hg init testeol
$ cd testeol
$ "$PYTHON" -c "open('a', 'wb').write(b'1\r\n2\r\n3\r\n4')"
$ hg ci -Am adda
adding a
$ "$PYTHON" -c "open('a', 'wb').write(b'1\r\n2\r\n33\r\n4')"
$ hg qnew patch1
$ hg qpop
popping patch1
patch queue now empty
$ "$PYTHON" -c "open('a', 'wb').write(b'1\r\n22\r\n33\r\n4')"
$ hg ci -m changea
$ hg --config 'patch.eol=LF' qpush
applying patch1
patching file a
Hunk #1 FAILED at 0
1 out of 1 hunks FAILED -- saving rejects to file a.rej
patch failed, unable to continue (try -v)
patch failed, rejects left in working directory
errors during apply, please fix and qrefresh patch1
[2]
$ hg qpop
popping patch1
patch queue now empty
$ cat a.rej
--- a
+++ a
@@ -1,4 +1,4 @@
1\r (esc)
2\r (esc)
-3\r (esc)
+33\r (esc)
4
\ No newline at end of file
$ hg --config 'patch.eol=auto' qpush
applying patch1
patching file a
Hunk #1 FAILED at 0
1 out of 1 hunks FAILED -- saving rejects to file a.rej
patch failed, unable to continue (try -v)
patch failed, rejects left in working directory
errors during apply, please fix and qrefresh patch1
[2]
$ hg qpop
popping patch1
patch queue now empty
$ cat a.rej
--- a
+++ a
@@ -1,4 +1,4 @@
1\r (esc)
2\r (esc)
-3\r (esc)
+33\r (esc)
4
\ No newline at end of file
$ cd ..