#!/usr/bin/env bash
#
# test-targets.sh unit|images|oracle|kernel|lwext4 — print the `cargo test`
# target arguments for one tier of the suite.
#
#   unit    the library, the binaries, and every tests/*.rs that reaches
#           neither a fixture nor the VM: no tool, no kernel, no harness
#   images  the tests that read a fixture but need no VM — everything a
#           host without KVM (GitHub's arm64 runners) can still run
#   oracle  every tests/*.rs that runs an e2fsprogs tool (in the VM)
#   kernel  every tests/*.rs that mounts one of our images with the real
#           kernel (in the VM)
#   lwext4  every tests/*.rs that asks lwext4 — a third implementation,
#           built in the VM by scripts/vm-setup.sh — what it sees
#
# DERIVED FROM THE TESTS THEMSELVES, not from a list someone has to keep:
# a test names a fixture by its test-disks/ path or through
# fs_ext4_test_support::fixture, reaches a tool only through
# `oracle` / `assert_e2fsck_clean`, and the kernel only through
# `guest_kernel_*` — the helpers that fail, never skip, when the VM or
# the tool is missing. tests/test_contract.rs fails if a test reaches
# either any other way, so the classification cannot drift.
#
# THE TIERS ARE DISJOINT, so the tasks together run each file once. A
# file that reaches more than one oracle is placed at the most specific:
# lwext4 first, then the kernel, then the tools. A cross-validation test
# formats its volume with `mke2fs` and its verdict is still lwext4's.
#
# Library tests that need a fixture or the VM live in modules named
# `needs_host`; `unit` excludes them with cargo's name filter, and
# `chore test` runs everything.
set -euo pipefail

REPO="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd -P)"
HOST='test-disks|fixture\(|oracle\(|assert_e2fsck_clean\(|guest_kernel_|lwext4_'
VM='oracle\(|assert_e2fsck_clean\(|guest_kernel_|lwext4_'
TOOL='oracle\(|assert_e2fsck_clean\('
KERNEL='guest_kernel_'
LWEXT4='lwext4_report\(|lwext4_write\(|lwext4_refusal\('

tier="${1:-}"
args=()
for f in "$REPO"/tests/*.rs; do
    name="$(basename "$f" .rs)"
    case "$tier" in
        unit) grep -qE "$HOST" "$f" || args+=(--test "$name") ;;
        images)
            if grep -qE "$HOST" "$f" && ! grep -qE "$VM" "$f"; then
                args+=(--test "$name")
            fi
            ;;
        oracle)
            if grep -qE "$TOOL" "$f" && ! grep -qE "$KERNEL|$LWEXT4" "$f"; then
                args+=(--test "$name")
            fi
            ;;
        kernel)
            if grep -qE "$KERNEL" "$f" && ! grep -qE "$LWEXT4" "$f"; then
                args+=(--test "$name")
            fi
            ;;
        lwext4) grep -qE "$LWEXT4" "$f" && args+=(--test "$name") ;;
        *) echo "usage: test-targets.sh unit|images|oracle|kernel|lwext4" >&2; exit 2 ;;
    esac
done
case "$tier" in
    unit) printf '%s\n' --lib --bins "${args[@]}" -- --skip needs_host:: ;;
    *) printf '%s\n' "${args[@]}" ;;
esac