view tests/test-issue1102.t @ 31209:dd2364f5180a

localrepo: handle rename with hardlinks properly

In "aftertrans", we rename "journal.*" to "undo.*". We expect "journal.*"
files to disappear after renaming.

However, if "journal.foo" and "undo.foo" refer to a same file (hardlink),
rename may be a no-op, leaving both files on disk, according to Linux
manpage [1]:

    If oldpath and newpath are existing hard links referring to the same
    file, then rename() does nothing, and returns  a  suc‐ cess status.

The POSIX specification [2] is not very clear about what to do.

To be safe, remove "undo.*" before the rename so "journal.*" cannot be left
on disk.

[1]: http://man7.org/linux/man-pages/man2/rename.2.html
[2]: http://pubs.opengroup.org/onlinepubs/9699919799/

  $ rm -rf a
  $ hg init a
  $ cd a
  $ echo a > a
  $ hg ci -Am0
  adding a
  $ hg tag t1 # 1
  $ hg tag --remove t1 # 2

  $ hg co 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg tag -f -r0 t1
  $ hg tags
  tip                                3:a49829c4fc11
  t1                                 0:f7b1eb17ad24

  $ cd ..