SYNOPSIS

git drover --branch <branch>
           (--cherry-pick <change> | --continue [path_to_workdir] |
            --abort [path_to_workdir])
           [--parent_checkout <path-to-existing-checkout>]
           [--verbose] [--dry-run]

DESCRIPTION

git drover applies a commit to a release branch. It creates a new workdir from an existing checkout to avoid downloading a new checkout without affecting the existing checkout.

git drover does not support reverts. See the EXAMPLE section for the equivalent sequence of commands to run.

OPTIONS

--branch <branch>

The branch to cherry-pick the commit to.

--cherry-pick <commit>

The commit to cherry-pick.

--continue [path_to_workdir]

Continue a cherry-pick that required manual resolution. The path to the drover workdir is optional. If unspecified, the current directory is used.

--abort [path_to_workdir]

Abort a cherry-pick that required manual resolution and clean up its workdir. The path to the drover workdir is optional. If unspecified, the current directory is used.

--parent_checkout

The path to the chromium checkout to use as the source for a creating git-new-workdir workdir to use for cherry-picking. If unspecified, the current directory is used.

-v
--verbose

Enable verbose logging.

--dry-run

Skip landing the cherry-pick. Just ensure that the commit can be cherry-picked into the branch.

EXAMPLE

PREREQUISITES

Before working with branches, you must gclient sync --with_branch_heads at least once to fetch the branches.

Merge Example

# Here's a commit (from some.committer) that we want to 'drover'.
$ git log -n 1 --pretty=fuller
commit c4c505c80a710432a95089cd7dca83e801bd3787
Author:     some.committer <some.committer@chromium.org>
AuthorDate: Thu Apr 10 08:54:46 2014 +0000
Commit:     some.committer <some.committer@chromium.org>
CommitDate: Thu Apr 10 08:54:46 2014 +0000

    This change needs to go to branch 9999

# Now do the 'drover'.
$ git drover --branch 9999 --cherry-pick c4c505c80a710432a95089cd7dca83e801bd3787
Going to cherry-pick
"""
commit c4c505c80a710432a95089cd7dca83e801bd3787
Author: some.committer <some.committer@chromium.org>
Date:   Thu Apr 10 08:54:46 2014 +0000

    This change needs to go to branch 9999
"""
to 9999. Continue (y/n)? y

# A cl is uploaded to rietveld, where it can be reviewed before landing.

About to land on 9999. Continue (y/n)? y
# The cherry-pick cl is landed on the branch 9999.

Merge with Conflicts Example

# Here's a commit (from some.committer) that we want to 'drover'.
$ git log -n 1 --pretty=fuller
commit 1bf3c1360a47ee7db9ab3a1960bada575652ab18
Author:     some.committer <some.committer@chromium.org>
AuthorDate: Thu Apr 10 08:54:46 2014 +0000
Commit:     some.committer <some.committer@chromium.org>
CommitDate: Thu Apr 10 08:54:46 2014 +0000

    This change needs to go to branch 9999

# Now do the 'drover'.
$ git drover --branch 9999 --cherry-pick 1bf3c1360a47ee7db9ab3a1960bada575652ab18
Going to cherry-pick
"""
commit 1bf3c1360a47ee7db9ab3a1960bada575652ab18
Author: some.committer <some.committer@chromium.org>
Date:   Thu Apr 10 08:54:46 2014 +0000

    This change needs to go to branch 9999
"""
to 9999. Continue (y/n)? y

Error: Patch failed to apply.

A workdir for this cherry-pick has been created in
  /tmp/drover_9999

To continue, resolve the conflicts there and run
  git drover --continue /tmp/drover_9999

To abort this cherry-pick run
  git drover --abort /tmp/drover_9999

$ pushd /tmp/drover_9999
# Manually resolve conflicts.
$ git add path/to/file_with_conflicts
$ popd
$ git drover --continue /tmp/drover_9999

# A cl is uploaded to rietveld, where it can be reviewed before landing.

About to land on 9999. Continue (y/n)? y
# The cherry-pick cl is landed on the branch 9999.

Revert Example

# Make sure we have the most up-to-date branch sources.
$ git fetch

# Checkout the branch with the change we want to revert.
$ git checkout -b drover_9999 branch-heads/9999
Branch drover_9999 set up to track remote ref refs/branch-heads/9999.

# Here's the commit we want to revert.
$ git log -n 1
commit 62b99a198636d608dd761b8f87714627154dbd34
Author: some.committer <some.committer@chromium.org>
Date:   Thu Apr 10 08:54:46 2014 +0000

    This change is horribly broken.

# Now do the revert.
$ git revert 62b99a198636d608dd761b8f87714627154dbd34

# That reverted the change and committed the revert.
$ git log -n 1
commit 5ae4e652a29fd78de0ef0a9560878e5ae95c6c82
Author: you <you@chromium.org>
Date:   Thu Apr 10 09:11:36 2014 +0000

    Revert "This change is horribly broken."

    This reverts commit 62b99a198636d608dd761b8f87714627154dbd34.

# As with old drover, reverts are generally OK to commit without LGTM.
$ git cl upload -r some.committer@chromium.org --send-mail
$ git cl land --bypass-hooks

If your cherrypick onto a release branch gets reverted, do not create a new cherrypick from master onto that release branch. Instead, use the "Reland" button on the original cherrypick CL.

Manual Merge Example

# Make sure we have the most up-to-date branch sources.
$ git fetch

# Here's a commit (from some.committer) that we want to 'drover'.
$ git log -n 1 --pretty=fuller
commit 91ee663980fecd3bb7d6e8e166458e84b4e02d99
Author:     some.committer <some.committer@chromium.org>
AuthorDate: Thu Apr 10 08:54:46 2014 +0000
Commit:     some.committer <some.committer@chromium.org>
CommitDate: Thu Apr 10 08:54:46 2014 +0000

    This change needs to go to branch 9999

# Checkout the branch we want to 'drover' to.
$ git checkout -b drover_9999 branch-heads/9999
Branch drover_9999 set up to track remote ref refs/branch-heads/9999.

# Now do the 'drover'.
# IMPORTANT!!! Do Not leave off the '-x' flag
$ git cherry-pick -x 91ee663980fecd3bb7d6e8e166458e84b4e02d99
[drover_9999 73a5705] This change needs to go to branch 9999
 Author: some.committer <some.committer@chromium.org>
 Date: Thu Apr 10 08:54:46 2014 +0000
 1 file changed, 1 insertion(+)
 create mode 100644 modified_file

# That took the code authored by some.committer and committed it to
# the branch by the person who drovered it (i.e. you).
$ git log -n 1 --pretty=fuller
commit 73a5705417e67c31f93d27fdee8240204082b5ef
Author:     some.committer <some.committer@chromium.org>
AuthorDate: Thu Apr 10 08:54:46 2014 +0000
Commit:     you <you@chromium.org>
CommitDate: Thu Apr 10 09:11:36 2014 +0000

    This change needs to go to branch 9999

    (cherry picked from commit 91ee663980fecd3bb7d6e8e166458e84b4e02d99)

# Looks good. Ship it!
$ git cl upload
# Wait for LGTM or TBR it.
$ git cl land
# Or skip the LGTM/TBR and just 'git cl land --bypass-hooks'

If git cl upload errors out, the branch you’re uploading to probably has a CL with the same Change-Id. Instead of cherry-picking manually, use the Reland button in the Gerrit UI to create a new CL, and patch that CL into your client.

SEE ALSO

git-cherry-pick(1), git-revert(1)

CHROMIUM DEPOT_TOOLS

Part of the chromium depot_tools(7) suite. These tools are meant to assist with the development of chromium and related projects. Download the tools from here.