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|
module Bytebuffer = Cohttp_lwt.Private.Bytebuffer
let%expect_test "read" =
let line = "foobar\r\n" in
let test buf_size =
let buf = Bytebuffer.create buf_size in
let refill =
let line_pos = ref 0 in
let reads_left = ref 10 in
fun buf ~pos ~len ->
if !reads_left = 0 then raise Exit;
decr reads_left;
let available = String.length line - !line_pos in
if available = 0 then Lwt.return `Eof
else
let read_len = min len available in
BytesLabels.blit_string ~src:line ~src_pos:!line_pos ~dst:buf
~dst_pos:pos ~len:read_len;
line_pos := !line_pos + read_len;
Lwt.return (`Ok read_len)
in
let open Lwt.Syntax in
Lwt_main.run
@@ Lwt.catch
(fun () ->
let+ res = Bytebuffer.read_line buf refill in
match res with
| None -> print_endline "failed to read line"
| Some line -> Printf.printf "read line: %S\n" line)
(function
| Exit -> Lwt.return @@ print_endline "failed to read"
| _ -> assert false)
in
test (String.length line);
[%expect {| read line: "foobar" |}];
test (String.length line - 1);
[%expect {| read line: "foobar" |}]
|
