Merge remote-tracking branch 'nschum/rebasearguments'

Conflicts:
	README.md

README.md

@@ -42,6 +42,10 @@ By default, `git-up` will append the `--prune` flag to the `git fetch` command i
 
 Normally, `git-up` will only fetch remotes for which there is at least one local tracking branch. Setting this option will it `git-up` always fetch from all remotes, which is useful if e.g. you use a remote to push to your CI system but never check those branches out.
 
+### `git-up.rebase.arguments [string]`
+
+If this option is set, its contents will be used by `git-up` as additional arguments when it calls `git rebase`. For example, setting this to `--preserve-merges` will recreate your merge commits in the rebased branch.
+
 ### `git-up.rebase.log-hook "COMMAND"`
 
 Runs COMMAND every time a branch is rebased or fast-forwarded, with the old head as $1 and the new head as $2. This can be used to view logs or diffs of incoming changes. For example: `'echo "changes on $1:"; git log --oneline --decorate $1..$2'`

lib/git-up.rb

@@ -152,8 +152,9 @@ def log(branch, remote)
 
   def rebase(target_branch)
     current_branch = repo.head
+    arguments = config("rebase.arguments")
 
-    output, err = repo.git.sh("#{Grit::Git.git_binary} rebase #{target_branch.name}")
+    output, err = repo.git.sh("#{Grit::Git.git_binary} rebase #{arguments} #{target_branch.name}")
 
     unless on_branch?(current_branch.name) and is_fast_forward?(current_branch, target_branch)
       raise GitError.new("Failed to rebase #{current_branch.name} onto #{target_branch.name}", output+err)