Smart git-switch using fzf

git-sw.sh

#!/bin/bash

# Save this file as `git-sw` in your $PATH and run `chmod +x git-sw`.
# Run `git sw -` to switch to last branch.
# Run `git sw` to select branch using fzf.
# Run `git sw branch-name` to pass query to fzf.
#   If the argument is matched to existing branch, change to that immediately.
# Create new branch when query is not matched by `fzf --print-query | tail -1`.
#   ref: https://github.com/junegunn/fzf/issues/1693#issuecomment-699642792

git switch "$@" 2>/dev/null || \
  git branch --sort=-authordate --all | grep --invert-match HEAD | \
  fzf --query="$@" --print-query --cycle --no-multi \
  --header-first --header='Create new branch when query is not matched' \
  --preview="echo {} | sed 's/.* //' | \
    xargs git log -30 --pretty=format:'[%ad] %s <%an>' --date=format:'%F'" | \
  tail -1 | \
  sed 's/.* //' | sed 's#remotes/[^/]*/##' | \
  xargs --no-run-if-empty -I_ sh -c 'git switch _ || git switch --create _'