fix: else branch missing for when cd is aliased e.g. oh-my-bash

[allen-munsch]

hello

i've experienced an issue with gvm for a couple years now, and i was never really sure what was the cause

i tried to outline as best i could the issue, it only ever reared its head when i had both oh-my-bash and gvm installed at the same time

i think it has to do with the lack of an alias branch check

  $ bash test-cd-fix.sh /path/to/gvm                                                                                                                                                         
                                                                                                                                                                                             
  === BROKEN (original) ===                                                                                                                                                                  
  cd before gvm: cd is aliased to `_omb_plugin_nvm_cd'                                                                                                                                       
  cd after gvm:  cd is aliased to `_omb_plugin_nvm_cd'                                                                                                                                       
  PWD before: /some/dir                                                                                                                                                                      
  PWD after:  /some/dir  (EXPECTED /tmp/gvm-cd-test-XXXXX)                                                                                                                                   
  FAIL                                                                                                                                                                                       
                                                                                                                                                                                             
  === FIXED ===                                                                                                                                                                              
  cd before gvm: cd is aliased to `_omb_plugin_nvm_cd'                                                                                                                                       
  cd after gvm:  cd is aliased to `_omb_plugin_nvm_cd'                                                                                                                                       
  PWD before: /some/dir                                                                                                                                                                      
  PWD after:  /tmp/gvm-cd-test-XXXXX                                                                                                                                                         
  PASS                                                                                                                                                                                       

test-cd-fix.sh :

#!/usr/bin/env bash
# ------------------------------------------------------------------
# Reproduce: when another shell framework (e.g. oh-my-bash) aliases
# cd, gvm's cd() wrapper silently drops the directory change because
# its save-logic only handles cd-as-function and cd-as-builtin, but
# not cd-as-alias.  __gvm_oldcd is never created, so the `cd` in the
# wrapper is a no-op.
#
# Fixed by adding an `else` branch that falls back to builtin cd.
#
# Usage:
#   git -C /path/to/gvm checkout -- scripts/env/cd   # apply the fix
#   bash test-cd-fix.sh /path/to/gvm
# ------------------------------------------------------------------
set -uo pipefail  # no -e: gvm's cd() may return non-zero if no Go installed

GVM_REPO="${1:?Usage: $0 /path/to/gvm/repo}"

export GVM_ROOT="$GVM_REPO"
export GVM_DEBUG=0

# Minimal gvm bootstrap (env/cd depends on these helpers)
set +u  # gvm internals reference ZSH_VERSION bare
# shellcheck source=/dev/null
. "$GVM_ROOT/scripts/functions"
. "$GVM_ROOT/scripts/function/_bash_pseudo_hash" 2>/dev/null || true
. "$GVM_ROOT/scripts/function/_shell_compat"     2>/dev/null || true

# Shims: we don't have a Go installation, but cd() will try to resolve
# .go-version / .go-pkgset.  Make those paths quiet.
display_error()                { :; }
__gvm_munge_path()             { echo "$PATH"; }
__gvm_read_environment_file()  { return 1; }
__gvmp_find_closest_dot_go_version() { return 1; }
__gvmp_find_closest_dot_go_pkgset()  { return 1; }
__gvmp_read_dot_go_version()   { return 1; }
__gvmp_read_dot_go_pkgset()    { return 1; }

# ------------------------------------------------------------------
# Step 1: alias cd like oh-my-bash's nvm plugin does
# ------------------------------------------------------------------
shopt -s expand_aliases
_omb_plugin_nvm_cd() { command cd "$@" || return "$?"; }
alias cd='_omb_plugin_nvm_cd'

echo "cd before gvm: $(type cd)"

# ------------------------------------------------------------------
# Step 2: source gvm's env/cd (discard noise from go-version scan)
# ------------------------------------------------------------------
. "$GVM_ROOT/scripts/env/cd" 2>/dev/null
echo "cd after gvm:  $(type cd | head -1)"

# ------------------------------------------------------------------
# Step 3: does cd actually change directory?
# ------------------------------------------------------------------
START_DIR="$PWD"
TMPDIR="/tmp/gvm-cd-test-$$"
mkdir -p "$TMPDIR"
trap 'cd / 2>/dev/null; rm -rf "$TMPDIR"' EXIT

echo ""
echo "PWD before: $START_DIR"
cd "$TMPDIR" 2>/dev/null

if [[ "$PWD" == "$TMPDIR" ]]; then
    echo "PWD after:  $PWD"
    echo ""
    echo "PASS"
    exit 0
else
    echo "PWD after:  $PWD  (EXPECTED $TMPDIR)"
    echo ""
    echo "FAIL"
    exit 1
fi