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|
(* This file is part of Lwt, released under the MIT license. See LICENSE.md for
details, or visit https://github.com/ocsigen/lwt/blob/master/LICENSE.md. *)
open Lwt.Syntax
open Test
let l = [1; 2; 3; 4; 5]
let a = Lwt_seq.of_list l
let rec pause n =
if n <= 0 then
Lwt.return_unit
else
let* () = Lwt.pause () in
pause (n - 1)
let pause n = pause (n mod 5)
let b =
Lwt_seq.unfold_lwt
(function
| [] -> let+ () = pause 2 in None
| x::xs -> let+ () = pause (x+2) in Some (x, xs))
l
let suite_base = suite "lwt_seq" [
test "fold_left" begin fun () ->
let n = ref 1 in
Lwt_seq.fold_left (fun acc x ->
let r = x = !n && acc in
incr n; r) true a
end;
test "fold_left_s" begin fun () ->
let n = ref 1 in
Lwt_seq.fold_left_s (fun acc x ->
let r = x = !n && acc in
incr n; Lwt.return r) true a
end;
test "map" begin fun () ->
let v = Lwt_seq.map (fun x -> (x * 2)) a in
let+ l' = Lwt_seq.to_list v in
l' = [2; 4; 6; 8; 10]
end;
test "map_s" begin fun () ->
let v = Lwt_seq.map_s (fun x -> Lwt.return (x * 2)) a in
let+ l' = Lwt_seq.to_list v in
l' = [2; 4; 6; 8; 10]
end;
test "filter" begin fun () ->
let v = Lwt_seq.filter (fun x -> (x mod 2 = 0)) a in
let+ l' = Lwt_seq.to_list v in
l' = [2; 4]
end;
test "filter_s" begin fun () ->
let v = Lwt_seq.filter_s (fun x -> Lwt.return (x mod 2 = 0)) a in
let+ l' = Lwt_seq.to_list v in
l' = [2; 4]
end;
test "iter_n(1)" begin fun () ->
let max_concurrency = 1 in
let running = ref 0 in
let sum = ref 0 in
let f x =
incr running;
assert (!running <= max_concurrency);
let* () = pause x in
sum := !sum + x;
decr running;
Lwt.return_unit
in
let* () = Lwt_seq.iter_n ~max_concurrency f a in
assert (!sum = List.fold_left (+) 0 l);
sum := 0;
let* () = Lwt_seq.iter_n ~max_concurrency f b in
assert (!sum = List.fold_left (+) 0 l);
Lwt.return_true
end;
test "iter_n(2)" begin fun () ->
let max_concurrency = 2 in
let running = ref 0 in
let sum = ref 0 in
let f x =
incr running;
assert (!running <= max_concurrency);
let* () = pause x in
sum := !sum + x;
decr running;
Lwt.return_unit
in
let* () = Lwt_seq.iter_n ~max_concurrency f a in
assert (!sum = List.fold_left (+) 0 l);
sum := 0;
let* () = Lwt_seq.iter_n ~max_concurrency f b in
assert (!sum = List.fold_left (+) 0 l);
Lwt.return_true
end;
test "iter_n(100)" begin fun () ->
let max_concurrency = 100 in
let running = ref 0 in
let sum = ref 0 in
let f x =
incr running;
assert (!running <= max_concurrency);
let* () = pause x in
sum := !sum + x;
decr running;
Lwt.return_unit
in
let* () = Lwt_seq.iter_n ~max_concurrency f a in
assert (!sum = List.fold_left (+) 0 l);
sum := 0;
let* () = Lwt_seq.iter_n ~max_concurrency f b in
assert (!sum = List.fold_left (+) 0 l);
Lwt.return_true
end;
test "filter_map" begin fun () ->
let v = Lwt_seq.filter_map (fun x ->
if x mod 2 = 0 then Some (x * 2) else None) a
in
let+ l' = Lwt_seq.to_list v in
l' = [4; 8]
end;
test "filter_map_s" begin fun () ->
let v = Lwt_seq.filter_map_s (fun x ->
Lwt.return (if x mod 2 = 0 then Some (x * 2) else None)) a
in
let+ l' = Lwt_seq.to_list v in
l' = [4; 8]
end;
test "unfold" begin fun () ->
let range first last =
let step i = if i > last then None else Some (i, succ i) in
Lwt_seq.unfold step first
in
let* a = Lwt_seq.to_list (range 1 3) in
let+ b = Lwt_seq.to_list (range 1 0) in
([1;2;3] = a) &&
([] = b)
end;
test "unfold_lwt" begin fun () ->
let range first last =
let step i =
if i > last then Lwt.return_none else Lwt.return_some (i, succ i)
in
Lwt_seq.unfold_lwt step first
in
let* a = Lwt_seq.to_list (range 1 3) in
let+ b = Lwt_seq.to_list (range 1 0) in
([1;2;3] = a) &&
([] = b)
end;
test "fold-into-exception-from-of-seq" begin fun () ->
let fail = fun () -> failwith "XXX" in
let seq = fun () -> Seq.Cons (1, (fun () -> Seq.Cons (2, fail))) in
let a = Lwt_seq.of_seq seq in
let+ n =
Lwt.catch
(fun () -> Lwt_seq.fold_left (+) 0 a)
(function
| Failure x when x = "XXX" -> Lwt.return (-1)
| exc -> raise exc)
in
n = (-1)
end;
test "fold-into-immediate-exception-from-of-seq" begin fun () ->
let fail = fun () -> failwith "XXX" in
let seq = fail in
let a = Lwt_seq.of_seq seq in
let+ n =
Lwt.catch
(fun () -> Lwt_seq.fold_left (+) 0 a)
(function
| Failure x when x = "XXX" -> Lwt.return (-1)
| exc -> raise exc)
in
n = (-1)
end;
test "fold-into-exception-from-of-seq-lwt" begin fun () ->
let fail = fun () -> failwith "XXX" in
let seq: int Lwt.t Seq.t = fun () ->
Seq.Cons (Lwt.return 1,
fun () ->
Seq.Cons (Lwt.return 2, fail)) in
let a = Lwt_seq.of_seq_lwt seq in
let+ n =
Lwt.catch
(fun () -> Lwt_seq.fold_left (+) 0 a)
(function
| Failure x when x = "XXX" -> Lwt.return (-1)
| exc -> raise exc)
in
n = (-1)
end;
test "fold-into-immediate-exception-from-of-seq-lwt" begin fun () ->
let fail = fun () -> failwith "XXX" in
let seq: int Lwt.t Seq.t = fail in
let a = Lwt_seq.of_seq_lwt seq in
let+ n =
Lwt.catch
(fun () -> Lwt_seq.fold_left (+) 0 a)
(function
| Failure x when x = "XXX" -> Lwt.return (-1)
| exc -> raise exc)
in
n = (-1)
end;
]
let fs = [(+); (-); (fun x _ -> x); min; max]
let ls = [
[];
l;
l@l@l;
List.rev l;
[0;0;0];
[max_int;0;min_int];
[max_int;max_int];
]
let cs = [0;1;max_int;min_int;44;5]
let with_flc test =
Lwt_list.for_all_s
(fun f ->
Lwt_list.for_all_s
(fun l ->
Lwt_list.for_all_s
(fun c -> test f l c)
cs)
ls)
fs
let equals l1 seq2 =
let* l2 = Lwt_seq.to_list seq2 in
Lwt.return (l1 = l2)
let commutes lf sf l =
equals (lf l) (sf (Lwt_seq.of_list l))
let suite_fuzzing = suite "lwt_seq(pseudo-fuzzing)" [
test "map" begin fun () ->
with_flc (fun f l c ->
let lf = List.map (fun x -> f x c) in
let sf = Lwt_seq.map (fun x -> f x c) in
commutes lf sf l
)
end;
test "map_s" begin fun () ->
with_flc (fun f l c ->
let lf = List.map (fun x -> f x c) in
let sf = Lwt_seq.map_s (fun x -> Lwt.return (f x c)) in
commutes lf sf l
)
end;
test "iter" begin fun () ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r] in
let sf s =
let r = ref c in
fun () ->
let* () = Lwt_seq.iter (fun x -> r := f !r x) s in
Lwt.return (Lwt_seq.Cons (!r, Lwt_seq.empty)) in
commutes lf sf l
)
end;
test "iter_s" begin fun () ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r] in
let sf s =
let r = ref c in
fun () ->
let* () = Lwt_seq.iter_s (fun x -> r := f !r x; Lwt.return_unit) s in
Lwt.return (Lwt_seq.Cons (!r, Lwt_seq.empty)) in
commutes lf sf l
)
end;
(* the [f]s commute sufficiently for parallel execution *)
test "iter_p" begin fun () ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r]
in
let sf s =
Lwt_seq.return_lwt @@
let r = ref c in
let+ () = Lwt_seq.iter_p (fun x -> r := f !r x; Lwt.return_unit) s in
!r
in
commutes lf sf l
)
end;
test "iter_p (pause)" begin fun () ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r]
in
let sf s =
Lwt_seq.return_lwt @@
let r = ref c in
let+ () =
Lwt_seq.iter_p
(fun x ->
let* () = pause x in
r := f !r x;
pause x)
s
in
!r
in
commutes lf sf l
)
end;
test "iter_n" begin fun () ->
l |> Lwt_list.for_all_s @@ fun max_concurrency ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r] in
let sf s =
Lwt_seq.return_lwt @@
let r = ref c in
let+ () = Lwt_seq.iter_n ~max_concurrency (fun x -> r := f !r x; Lwt.return_unit) s in
!r
in
commutes lf sf l
)
end;
test "iter_n (pause)" begin fun () ->
l |> Lwt_list.for_all_s @@ fun max_concurrency ->
with_flc (fun f l c ->
let lf l =
let r = ref c in
List.iter (fun x -> r := f !r x) l;
[!r] in
let sf s =
Lwt_seq.return_lwt @@
let r = ref c in
let+ () =
Lwt_seq.iter_n ~max_concurrency
(fun x ->
let* () = pause x in
r := f !r x;
pause x)
s
in
!r
in
commutes lf sf l
)
end;
]
|
