Add git move

[salcode]

This tweet about committing to the wrong branch and then wanting to move those commits led to a thread, which culminated in

[alias]
	moveexisting = "!f() { MESSAGE=$(git log -1 HEAD --pretty=format:%s) && git reset HEAD~ --soft && git stash && git checkout $1 && git stash apply && git add . && git commit -m \"$MESSAGE\"; }; f"
	movenew = "!f() { git branch $1; git reset HEAD~1 --soft; git checkout $1; }; f"
	move = "!sh -c 'if [ `git rev-parse --verify "'$1'"` ]; then git moveexisting "'$1'"; else git movenew "'$1'"; fi'"

source

[salcode]

Looking at this and the original, I don't think git stash is the right tool for the job. I think git cherry-pick makes more sense.

The first thing we need is to decide if our target branch is new or already exists.

I like the check above but I've added the --quiet parameter to reduce the noise

	move = "!sh -c 'if [ `git rev-parse --verify --quiet "'$1'"` ]; \

See StackOverflow Is there a better way to find out if a local git branch exists?

Two Different Tasks

There are two rather different tasks here depending on whether or not the branch already exists.

Branch Exists

• Checkout the branch
• Cherry pick the specified number of commits (either based on the parameter or default to 1) from the end of the original branch.
• Remove the moved commits from the original branch.

Branch Does Not Exist

(this version is easier)

• Create a new branch. By default, the new branch will include all the commits from the original branch (including those we are moving).
• Remove the "moved" commits from the original branch.

Implementation Notes:

The previous branch can be referenced with @{-1} (source).

We can define a default value for a parameter by using the format ${1:-defaultValue}, where $1 is the variable whose default we are setting. (source)

[salcode]

This is my current solution.

[alias]
	# Perform reset --hard on the specified branch
	# This allows us to remove the last n commits on a branch.
	# @param string $1 The branch where reset --hard should be applied.
	# @param string $2 The commit to be used as the new HEAD. Defaults to 'HEAD~1'.
	# e.g. git reset-hard-other-branch develop HEAD~3
	# performs git reset --hard HEAD~3 on branch `develop`.
	reset-hard-other-branch = "!f() { \
		git checkout $1;              \
		git reset --hard ${2:-HEAD~1}; \
		git checkout @{-1};           \
	}; f"

	# Cherry-pick the last n commits from the last used branch ( @{-1} ).
	# @param int $1 The number of commits to cherry-pick. Defaults to 1.
	cherry-pick-last-n-from-last-branch = "!f() { \
		git cherry-pick @{-1}~${1:-1}...@{-1}~0;   \
	}; f"

	# Move to the given branch the last n commits.
	# @param string $1 The destination branch (create if does not exist).
	# @param int    $2 The number of commits to move. Defaults to 1.
	move = "!sh -c 'if [ `git rev-parse --verify --quiet "'$1'"` ]; \
		then                                                        \
			git checkout "'$1'";                                    \
			git cherry-pick-last-n-from-last-branch "'${2:-1}'";     \
			git reset-hard-other-branch @{-1} HEAD~"'${2:-1}'";      \
		else                                                        \
			git checkout -b "'$1'";                                 \
			git reset-hard-other-branch @{-1} HEAD~"'${2:-1}'";      \
		fi'";