view tests/test-mq-eol.t @ 26375:3686fa2b8eee

windows: insert file positioning call between reads and writes

fopen() and fdopen() have a unique-to-Windows requirement that
transitions between read and write operations in files opened
in modes r+, w+, and a+ perform a file positioning call
(fsetpos, fseek, or rewind) in between. While the MSDN docs don't
say what will happen if this is not done, observations reveal
that Python raises an IOError with errno 0. Furthermore, I
/think/ this behavior isn't deterministic. But I can reproduce
it reliably with subsequent patches applied that open revlogs
in a+ mode and perform both reads and writes.

This patch introduces a proxy class for file handles opened
in r+, w+, and a+ mode on Windows. The class intercepts calls
and audits whether a file positioning function has been called
between read and write operations. If not, a dummy, no-op seek
to the current file position is performed. This appears to be
sufficient to "trick" Windows into allowing transitions between
read and writes without raising errors.

Test interactions between mq and patch.eol


  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > mq =
  > [diff]
  > nodates = 1
  > EOF

  $ cat > makepatch.py <<EOF
  > f = file('eol.diff', 'wb')
  > w = f.write
  > w('test message\n')
  > w('diff --git a/a b/a\n')
  > w('--- a/a\n')
  > w('+++ b/a\n')
  > w('@@ -1,5 +1,5 @@\n')
  > w(' a\n')
  > w('-b\r\n')
  > w('+y\r\n')
  > w(' c\r\n')
  > w(' d\n')
  > w('-e\n')
  > w('\ No newline at end of file\n')
  > w('+z\r\n')
  > w('\ No newline at end of file\r\n')
  > EOF

  $ cat > cateol.py <<EOF
  > import sys
  > for line in file(sys.argv[1], 'rb'):
  >     line = line.replace('\r', '<CR>')
  >     line = line.replace('\n', '<LF>')
  >     print line
  > EOF

  $ hg init repo
  $ cd repo
  $ echo '\.diff' > .hgignore
  $ echo '\.rej' >> .hgignore


Test different --eol values

  $ $PYTHON -c 'file("a", "wb").write("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 refresh 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 refresh 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 "file('a', 'wb').write('1\r\n2\r\n3\r\n4')"
  $ hg ci -Am adda
  adding a
  $ $PYTHON -c "file('a', 'wb').write('1\r\n2\r\n33\r\n4')"
  $ hg qnew patch1
  $ hg qpop
  popping patch1
  patch queue now empty
  $ $PYTHON -c "file('a', 'wb').write('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 refresh 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 refresh 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 ..