let triple f1 f2 f3 ppf (v1, v2, v3) =
  Format.fprintf ppf "(%a,%a,%a)" f1 v1 f2 v2 f3 v3

let fmt = Fmt.Dump.(list (triple string string (list string)))
let print phr = Format.printf "%a" fmt phr

let check phrase =
  let output = snd (Js_top_worker.Impl.mangle_toplevel true phrase []) in
  print_endline "input:";
  Printf.printf "{|%s|}\n" phrase;
  print_endline "output:";
  Printf.printf "{|%s|}\n" output;
  let output_mapped = String.map (fun c -> if c = ' ' then '.' else c) output in
  print_endline "output mapped:";
  Printf.printf "{|%s|}\n" output_mapped

let%expect_test _ =
  check "# foo;; junk\n  bar\n# baz;;\n  moo\n# unterminated;; foo\n";
  [%expect
    {xxx|
    input:
    {|# foo;; junk
      bar
    # baz;;
      moo
    # unterminated;; foo
    |}
    output:
    {|  foo;;

      baz;;

      unterminated;;
    |}
    output mapped:
    {|..foo;;.....
    .....
    ..baz;;
    .....
    ..unterminated;;....
    |}
    |xxx}]

let%expect_test _ =
  check "# 1+2;;\n- 3 : int\n  \n";
  [%expect
    {xxx|
    input:
    {|# 1+2;;
    - 3 : int

    |}
    output:
    {|  1+2;;


    |}
    output mapped:
    {|..1+2;;
    .........
    ..
    |}
    |xxx}]

let%expect_test _ =
  check "# 1+2;;";
  [%expect
    {xxx|
    input:
    {|# 1+2;;|}
    output:
    {|  1+2;;|}
    output mapped:
    {|..1+2;;|}
    |xxx}]

let%expect_test _ =
  check "# 1+2;;\nx\n";
  [%expect
    {xxx|
    input:
    {|# 1+2;;
    x
    |}
    output:
    {|  1+2;;

    |}
    output mapped:
    {|..1+2;;
    .
    |}
    |xxx}]

let%expect_test _ =
  check "# let ;;\n  foo";
  [%expect
    " \n\
    \ fallback parser\n\
    \ Got phrase\n\
    \ input:\n\
    \ {|# let ;;\n\
    \   foo|}\n\
    \ output:\n\
    \ {|  let ;;\n\
    \      |}\n\
    \ output mapped:\n\
    \ {|..let.;;\n\
    \ .....|}\n\
    \ "]

let%expect_test _ =
  check "# let x=1;;\n  foo\n\n# let y=2;;\n  bar\n\n";
  [%expect
    " \n\
    \ input:\n\
    \ {|# let x=1;;\n\
    \   foo\n\n\
    \ # let y=2;;\n\
    \   bar\n\n\
    \ |}\n\
    \ output:\n\
    \ {|  let x=1;;\n\n\n\
    \   let y=2;;\n\n\n\
    \ |}\n\
    \ output mapped:\n\
    \ {|..let.x=1;;\n\
    \ .....\n\n\
    \ ..let.y=2;;\n\
    \ .....\n\n\
    \ |}\n\
    \ "]