(** Tests for precommit. *)

let contains s sub =
  let len = String.length sub in
  let rec check i =
    if i + len > String.length s then false
    else if String.sub s i len = sub then true
    else check (i + 1)
  in
  check 0

let test_pre_commit_hook_valid () =
  let hook = Precommit.pre_commit_hook in
  Alcotest.(check bool) "is shell script" true (String.sub hook 0 2 = "#!");
  Alcotest.(check bool) "runs dune fmt" true (contains hook "dune fmt");
  Alcotest.(check bool)
    "checks staged files" true
    (contains hook "git diff --cached")

let test_commit_msg_hook_valid () =
  let hook = Precommit.commit_msg_hook in
  Alcotest.(check bool) "is shell script" true (String.sub hook 0 2 = "#!");
  Alcotest.(check bool) "filters AI lines" true (contains hook "Co-Authored-By");
  Alcotest.(check bool) "checks emojis" true (contains hook "emoji")

let suite =
  ( "precommit",
    [
      Alcotest.test_case "pre_commit_hook valid" `Quick
        test_pre_commit_hook_valid;
      Alcotest.test_case "commit_msg_hook valid" `Quick
        test_commit_msg_hook_valid;
    ] )