Updated bash/zsh function that cd to the root of git tree

Question

here's the updated version of the code for being reviewed. Fixes:

• "private" _cg function
• functions definition as cg() {}
• general clean-up

#!/bin/bash
# cd to the root of the current git directory
# If $PWD is submodule, will cd to the root of the top ancestor
# It requires to stay in the current directory, if the root is . or unknown,
# and use cd only once, to have a way to do `cd -`
cg() {
 _cg() {
 local top; top="$(git rev-parse --show-cdup)"
 top="${top:-./}"
 local super_root; super_root="$(git rev-parse --show-superproject-working-tree)"
 if [[ "$super_root" ]]; then
 printf '%s' "$top../"
 ( cd "$top../" && _cg || return )
 fi
 printf '%s' "$top"
 }
 local git_root
 git_root="$(_cg)"
 [[ "x${git_root}" != "x./" ]] && cd "${git_root}" && return || return 0
}

Answer 1

This is looking great. Thanks for incorporating the previous improvements and coming back for another round of review. I noticed a few new things this time:

• What does printf '%s' do for you that echo -n wouldn't? Using printf when you're just passing through a string seems a little odd to me. It should work either way, but printf would be more idiomatic for C where echo is much more common in shell scripts.
• Adding the x constants in the comparison [[ "x${git_root}" != "x./" ]] are not needed. Using the double square brackets deals with the disappearing variables. You would need the extra x for [ comparisons because empty arguments become non-existant arguments which causes an error when you try to compare the non-existant to something.
• I would use -n in the if [[ "$super_root" ]]; then line like so: if [[ -n "$super_root" ]]; then to make clear what you're trying to do there.

• Felixoid: I just found that didn't come back with "thank you". Thank you very much for your help! And the objectives behind the implementations: 1) I feel like echo -n is less portable than printf, that's why I stuck to it; 2) Thank you, I've learned something new; 3) perfectly makes sense too!