#!/usr/bin/env sh
# Fetch the build.zig.zon dependency tree with backoff. zig gives up on the
# first failed download, and the tangled.org archive endpoint rate-limits, so a
# cold cache could fail a pipeline before any check ran.
set -eu
zig="${ZIG:-.ci-cache/zig/zig}"
attempt=1
delay=5
while ! "$zig" build --fetch; do
  if [ "$attempt" -ge 6 ]; then
    echo "dependency fetch failed after $attempt attempts" >&2
    exit 1
  fi
  echo "dependency fetch failed (attempt $attempt); retrying in ${delay}s" >&2
  sleep "$delay"
  attempt=$((attempt + 1))
  delay=$((delay * 2))
done