Find the nearest parent branch of the current git branch

.gitconfig

[alias]
    parentalt = "!git show-branch | grep '*' | grep -v \"$(git rev-parse --abbrev-ref HEAD)\" | head -n1 | sed 's/.*\\[\\(.*\\)\\].*/\\1/' | sed 's/[\\^~].*//' #"
    parent = "!vbc=$(git rev-parse --abbrev-ref HEAD) && vbc_col=$(( $(git show-branch | grep '^[^\\[]*\\*' | head -1 | cut -d* -f1 | wc -c) - 1 )) && swimming_lane_start_row=$(( $(git show-branch | grep -n \"^[\\-]*$\" | cut -d: -f1) + 1 ))  && git show-branch | tail -n +$swimming_lane_start_row | grep -v \"^[^\\[]*\\[$vbc\" | grep \"^.\\{$vbc_col\\}[^ ]\" | head -n1 | sed 's/.*\\[\\(.*\\)\\].*/\\1/' | sed 's/[\\^~].*//'"

git-show-parent-singleLine-alias.sh

vbc=$(git rev-parse --abbrev-ref HEAD) && vbc_col=$(( $(git show-branch | grep '^[^\[]*\*' | head -1 | cut -d* -f1 | wc -c) - 1 )) && swimming_lane_start_row=$(( $(git show-branch | grep -n "^[\-]*$" | cut -d: -f1) + 1 ))  && git show-branch | tail -n +$swimming_lane_start_row | grep -v "^[^\[]*\[$vbc" | grep "^.\{$vbc_col\}[^ ]" | head -n1 | sed 's/.*\[\(.*\)\].*/\1/' | sed 's/[\^~].*//'

git-show-parent.sh

#!/usr/bin/bash
# Based on https://gist.github.com/joechrysler/6073741#gistcomment-1774657
vbc=$(git rev-parse --abbrev-ref HEAD) && vbc_col=$(( $(git show-branch | grep '^[^\[]*\*' | head -1 | cut -d* -f1 | wc -c) - 1 )) && swimming_lane_start_row=$(( $(git show-branch | grep -n "^[\-]*$" | cut -d: -f1) + 1 ))  && git show-branch | tail -n +$swimming_lane_start_row | grep -v "^[^\[]*\[$vbc" | grep "^.\{$vbc_col\}[^ ]" | head -n1 | sed 's/.*\[\(.*\)\].*/\1/' | sed 's/[\^~].*//'