view tests/test-bookmarks-strip.t @ 27430:e240e914d226 stable

revlog: seek to end of file before writing (issue4943)

Revlogs were recently refactored to open file handles in "a+" and use a
persistent file handle for reading and writing. This drastically
reduced the number of file handles being opened.

Unfortunately, it appears that some versions of Solaris lose the file
offset when performing a write after the handle has been seeked.

The simplest workaround is to seek to EOF on files opened in a+ mode
before writing to them, which is what this patch does.

Ideally, this code would exist in the vfs layer. However, this would
require creating a proxy class for file objects in order to provide a
custom implementation of write(). This would add overhead. Since
revlogs are the only files we open in a+ mode, the one-off workaround
in revlog.py should be sufficient.

This patch appears to have little to no impact on performance on my
Linux machine.

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init

  $ echo qqq>qqq.txt

rollback dry run without rollback information

  $ hg rollback
  no rollback information available
  [1]

add file

  $ hg add
  adding qqq.txt

commit first revision

  $ hg ci -m 1

set bookmark

  $ hg book test

  $ echo www>>qqq.txt

commit second revision

  $ hg ci -m 2

set bookmark

  $ hg book test2

update to -2 (deactivates the active bookmark)

  $ hg update -r -2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark test2)

  $ echo eee>>qqq.txt

commit new head

  $ hg ci -m 3
  created new head

bookmarks updated?

  $ hg book
     test                      1:25e1ee7a0081
     test2                     1:25e1ee7a0081

strip to revision 1

  $ hg strip 1
  saved backup bundle to $TESTTMP/.hg/strip-backup/*-backup.hg (glob)

list bookmarks

  $ hg book
     test                      0:5c9ad3787638
     test2                     0:5c9ad3787638