Treat matching kernel headers as a base system guarantee

test/shell.d/kernel-headers-migration-test.sh

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+set -euo pipefail
+source "$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)/base-test.sh"
+
+tmp_dir=$(mktemp -d)
+trap 'rm -rf "$tmp_dir"' EXIT
+mkdir -p "$tmp_dir/bin"
+export INSTALLED_PACKAGES="$tmp_dir/installed" CALL_LOG="$tmp_dir/calls"
+export PATH="$tmp_dir/bin:$ROOT/bin:$PATH"
+
+# Keep the real package helpers, but contain every pacman transaction here.
+cat > "$tmp_dir/bin/pacman" <<'SH'
+#!/bin/bash
+case "$1" in
+  -Q) grep -Fxq -- "$2" "$INSTALLED_PACKAGES" ;;
+  -S)
+    [[ ${FAIL_INSTALL:-0} == 0 ]] || exit 1
+    shift 3 # -S --noconfirm --needed
+    printf '%s\n' "$@" >> "$INSTALLED_PACKAGES"
+    printf '%s\n' "$@" >> "$CALL_LOG"
+    ;;
+  *) exit 1 ;;
+esac
+SH
+cat > "$tmp_dir/bin/sudo" <<'SH'
+#!/bin/bash
+[[ $1 == "pacman" ]] || exit 1
+"$@"
+SH
+chmod +x "$tmp_dir/bin/"*
+
+migration="$ROOT/migrations/1789444024.sh"
+for kernels in linux-omarchy linux-t2 'linux-omarchy linux-t2'; do
+  read -ra installed <<< "$kernels"
+  printf '%s\n' linux linux-headers "${installed[@]}" > "$INSTALLED_PACKAGES"
+  : > "$CALL_LOG"
+  bash -euo pipefail "$migration" >/dev/null
+  for kernel in "${installed[@]}"; do
+    grep -Fxq "$kernel-headers" "$INSTALLED_PACKAGES" || fail "$kernel gets its headers"
+  done
+  : > "$CALL_LOG"
+  bash -euo pipefail "$migration" >/dev/null
+  [[ ! -s $CALL_LOG ]] || fail "header repair is idempotent"
+  pass "missing headers are repaired once for $kernels"
+done
+
+printf '%s\n' linux linux-aarch64 > "$INSTALLED_PACKAGES"
+: > "$CALL_LOG"
+bash -euo pipefail "$migration" >/dev/null
+[[ ! -s $CALL_LOG ]] || fail "header repair skips unrelated kernels"
+pass "header repair skips unrelated kernels"
+
+echo linux-omarchy > "$INSTALLED_PACKAGES"
+if FAIL_INSTALL=1 bash -euo pipefail "$migration" >/dev/null; then
+  fail "a failed header installation must leave the migration pending"
+fi
+pass "header installation failure is propagated"