Re: [PATCHv2 5/5] fast-import: Fix minor data-loss issue with directories becoming symlinks

On Tue, Jul 6, 2010 at 1:34 PM, Shawn O. Pearce [off-list ref] wrote:

newren@gmail.com wrote:

quoted

From: Elijah Newren <redacted>

When fast-export runs across a directory changing to a symlink, it will
output the changes in the form
  M 120000 :239821 dir-changing-to-symlink
  D dir-changing-to-symlink/filename1
When fast-import sees the first line, it deletes the directory named
dir-changing-to-symlink (and any files below it) and creates a symlink in
its place.  When fast-import came across the second line, it was previously
trying to remove the file and relevant leading directories in
tree_content_remove(), and as a side effect it would delete the symlink
that was just created.  This resulted in the symlink silently missing from
the resulting repository.

Ugh.

I'm not against making the input parser more robust, but this is
a violation of the stream format from fast-export.  The stream is
incremental, a command like 'M' takes place immediately.  It is
wrong for a frontend to output 'M foo', then 'D foo/bar'.

IMHO, if fast-export is doing what you say above, the bug lies in
fast-export, and therefore the fix should too.

Okay, I'll fix up fast-export.  Do you want me to drop this
fast-import patch, or does it still make sense as an extra robustness
check?

Elijah