Trigger rspec on specs that have been affected between parent and current branch

diffospec.zsh

#!/usr/bin/env zsh

diffospec() {
  if [[ "$1" -eq "--help" ]]; then

    echo """
    Desc:  Runs rspec against files that have changed from a different commit
    Usage: diffospec <sha?>
    Examples...

        diffospec  # compares against parent branch by default
        diffospec 3efc2  # compares against #3efc2

    """

  else

    ref=$1; : ${ref:="$(git-parent-branch)"}
    echo "Spec'ing against $ref"

    specsWhereFileHasChangedPattern=$(
    git diff origin/$ref --name-only --diff-filter=ACMRTUXB \
    | ack -v spec \
    | perl -wnl -e '/^[^\/]+\/(.+)\.rb$/ and print "-wholename \"**/$1_spec.rb\" -o"' \
    | tr '\n' ' ' \
    | sed 's/ -o\s*$//'
    )

    specsWhereFileHasChanged=$(find spec $(echo $specsWhereFileHasChangedPattern | xargs))
    specsThatHaveChanged=$(git diff origin/$ref --name-only --diff-filter=ACMRTUXB | ack spec)

    specsToRun=$(echo $specsThatHaveChanged'\n'$specsWhereFileHasChanged | sort -u)

    echo $specsToRun | sed 's/^/- /'
    rspec $(echo $specsToRun | xargs)

  fi
}

git-current-branch() {
  git rev-parse --abbrev-ref HEAD
}

git-parent-branch() {
  git show-branch -a 2&>/dev/null \
  | ack '\*' \
  | ack -v "$(git-current-branch)" \
  | head -n1 \
  | perl -wnl -e '/\[([^\^\]]*)/ and print $1;'
}

Nice!