bundler shim for helping with upgrade of very old Ruby code into modern RubyGems / Bundler environment

bundle

#!/usr/bin/env bash
# Safe shim for Bundler that delegates to the system-installed `bundle`.
# This avoids relying on a project binstub and prevents recursion if bin/ is ahead of the real Bundler in PATH.
#
# Rationale:
# - Historically, some setups added ./bin to PATH (see .envrc). When a binstub existed, `bundle` could resolve here.
# - Modern Bundler does not require a binstub for itself. If this file is invoked, we forward to the real Bundler.
# - We temporarily remove this script's directory from PATH to avoid calling ourselves again.

set -euo pipefail

# Compute this script's directory
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# Build a PATH without SCRIPT_DIR to avoid recursion
PRUNED_PATH=""
OLD_IFS="$IFS"
IFS=":"
for dir in $PATH; do
  if [[ "$dir" != "$SCRIPT_DIR" && -n "$dir" ]]; then
    if [[ -z "$PRUNED_PATH" ]]; then
      PRUNED_PATH="$dir"
    else
      PRUNED_PATH="$PRUNED_PATH:$dir"
    fi
  fi
done
IFS="$OLD_IFS"
export PATH="$PRUNED_PATH"

# Exec the real Bundler from the pruned PATH
if command -v bundle >/dev/null 2>&1; then
  exec bundle "$@"
else
  echo "Error: Could not find Bundler ('bundle') in PATH after removing $SCRIPT_DIR." >&2
  echo "Please ensure Bundler is installed (e.g.,: gem install bundler) and available on your PATH." >&2
  exit 127
fi