prepare_gated

#!/usr/bin/env bash
#
# Clone or fetch bare repos for all gated repositories.
# Extends ./prepare by cloning bare repos for all gated extensions and skins.
# Assumes ./prepare has been run first (needs ref/integration/config.git).
# PARALLEL=N clones/fetches N repos at a time (default: sequential).
#
# Usage: ./prepare_gated
#        PARALLEL=1 ./prepare_gated
#
set -euo pipefail # exit on error, undefined vars, or pipe failures
. "$(dirname "$0")"/lib/setup # source shared setup (docker checks, shared vars, output capture, trace into the log)
. "$(dirname "$0")"/lib/clone_or_fetch # provides clone_or_fetch function

parallel="${PARALLEL:-0}" # PARALLEL=N clones N repos at a time; unset/0 = sequential (default)

# Build the list of Gerrit repos for all gated components.
# lib/build_component_list captures ./list_gated's output and checks its exit code —
# reading it via process substitution would swallow a non-zero exit, leaving repos[]
# empty and turning a broken config into a silent no-op run.
. "$(dirname "$0")"/lib/build_component_list # sets components[] from $1 or ./list_gated
# Convert each component path (e.g. "extensions/Echo") to its Gerrit repo ("mediawiki/extensions/Echo").
repos=() # array of Gerrit repo paths to clone or fetch
# ${components[@]+"${components[@]}"} is the bash 3.2-safe expansion under set -u (empty array -> no iterations).
for component in ${components[@]+"${components[@]}"}; do
  repos+=("mediawiki/${component}") # += appends to a bash array
done

if [ "$parallel" -lt 1 ]; then
  # --- Sequential mode (default) ---
  # ${repos[@]+"${repos[@]}"} is the bash 3.2-safe expansion under set -u (empty array -> no iterations).
  for repo in ${repos[@]+"${repos[@]}"}; do
    clone_or_fetch "$repo"
  done
else
  # --- Parallel mode: clone/fetch $parallel repos at a time (lib/run_waves) ---
  items=(${repos[@]+"${repos[@]}"})         # lib/run_waves processes this ambient items[] array
  _run_waves_job() { clone_or_fetch "$1"; } # worker: clone or fetch one repo ($1 = Gerrit repo path)
  . "$(dirname "$0")"/lib/run_waves         # launch the jobs, throttled to $parallel at a time
fi