Merge and delete branch in one step/command

This is an old question, but for those who stumble upon it looking for this functionality, you can now add a Git alias to accomplish this. For example, in .gitconfig:

# ...

[alias]
  mgd = "!git merge $1 && git branch -d $1; #"

Then, you could run git mgd branch-name to merge and delete a branch in one go. Note that the lowercase -d flag ensures that the branch will only be deleted if it has already been fully merged; thus, you don't have to worry about the first command not working correctly and then losing the branch.

The exclamation point at the beginning of the alias signifies that this is a bash command, and $1 stores the argument that the user passed in (i.e. the name of the branch to merge/delete).

NOTE: Do not leave out the comment character (#) at the end of the alias! It will not work without it. (Why?)

No, git doesn't support this at the same time.

However, you can run the commands in a shell conditionally:

git merge source-branch && git branch -d source-branch

Edit:

-d will only remove merged branches while -D will also remove unmerged branches, so -d will ensure that the branch is merged and you don't delete a branch by accident.

I will write a script.

git branch | grep -v master | xargs git merge &&
git branch | grep -v master | xargs git branch -d

Here the branch name master can be replaced by your current branch name.

Don't forget the &&. If the first line fails then the second is not executed.