git svn cherry pick ignored warning

Question

When I run git svn fetch it sometimes prints following warning:

W:svn cherry-pick ignored (/path/in/svn:<svn revision number list>) missing 55 commit(s) (eg 9129b28e5397c41f0a527818edd344bf264359af)

What this warning is about?

Answer 1

When someone does a "cherry-pick merge" with Subversion, Subversion records the commit that was merged in the metadata for the files and folders involved.

When you do a git svn fetch, Git sees that merge metadata, and tries to interpret it as a merge between the Git remote branches. All this message means is that Git tried to do that, but failed, so it'll record it as a regular commit rather than a merge.

It's not something you need to worry about unless you're seeing bugs in how Git picks up Subversion commits.

In more detail:

Say you have a Subversion repository with two branches A and B, with a matching Git svn repository:

A B   

*    r6
| *  r5
* |  r4
| *  r3
|/     
*    r2
*    r1

If you were to reintegrate branch B back into branch A, you'd use a command in a branch A working copy like svn merge -r 3:HEAD ^/branches/B or just svn merge --reintegrate ^/branches/B. Subversion would record metadata in svn:mergeinfo tags recording that this merge had taken place, and your next git svn fetch will see this metadata, see that branch B has been reintegrated into branch A, and record the corresponding commit in its history as a merge too.

If you just wanted a single commit from branch B in branch A (say r3 added a feature you need), but you don't want to reintegrate the entire branch yet, you'd instead use a Subversion command like svn merge -c 3 ^/branches/B. Again, Subversion would record merge metadata, and Git would see this and try to work out if it could record a branch merge as in the previous example. In this case it can't: branch A doesn't contain anything like branch B's r5. That's what triggers this warning.