ocaml-containers/tests/core/t_byte_buffer.ml
Simon Cruanes 10865eaced reformat
2022-07-04 13:36:06 -04:00

154 lines
3.5 KiB
OCaml

module T = (val Containers_testlib.make ~__FILE__ ())
include T
open CCByte_buffer;;
t @@ fun () ->
let b = create () in
is_empty b
;;
t @@ fun () ->
let b = create ~cap:32 () in
is_empty b
;;
t @@ fun () ->
let b = create () in
length b = 0
;;
t @@ fun () ->
let b = create ~cap:32 () in
length b = 0
let test_count = 2_500
open QCheck
type op =
| Add_char of char
| Add_string of string
| Get_contents
| Get of int
| Clear
| Shrink_to of int
| Set of int * char
let spf = Printf.sprintf
let str_op = function
| Add_char c -> spf "add_char %C" c
| Add_string s -> spf "add_string %S" s
| Get_contents -> "contents"
| Get i -> spf "get %d" i
| Clear -> "clear"
| Shrink_to n -> spf "shrink %d" n
| Set (i, c) -> spf "set %d %C" i c
let gen_op size : (_ * _) Gen.t =
let open Gen in
let base =
if size > 0 then
[
(1, 0 -- size >|= fun x -> Get x, size);
( 1,
0 -- size >>= fun x ->
printable >|= fun c -> Set (x, c), size );
(1, 0 -- size >|= fun x -> Shrink_to x, x);
]
else
[]
in
frequency
(base
@ [
1, return (Get_contents, size);
1, return (Clear, 0);
(3, printable >|= fun c -> Add_char c, size + 1);
( 1,
string_size (0 -- 100) ~gen:printable >|= fun s ->
Add_string s, size + String.length s );
])
let rec gen_l acc sz n =
let open Gen in
if n = 0 then
return (List.rev acc)
else
gen_op sz >>= fun (op, sz) -> gen_l (op :: acc) sz (n - 1)
let gen : op list Gen.t = Gen.sized (gen_l [] 0)
let is_valid ops =
let rec loop sz = function
| [] -> true
| Add_char _ :: tl -> loop (sz + 1) tl
| Clear :: tl -> loop 0 tl
| Add_string s :: tl -> loop (sz + String.length s) tl
| (Get n | Set (n, _)) :: tl -> n < sz && loop sz tl
| Get_contents :: tl -> loop sz tl
| Shrink_to x :: tl -> x <= sz && loop x tl
in
loop 0 ops
let shrink_op =
Iter.(
function
| Get_contents | Clear -> empty
| Get n -> Shrink.int n >|= fun n -> Get n
| Add_char c -> Shrink.char c >|= fun c -> Add_char c
| Add_string s -> Shrink.string s >|= fun s -> Add_string s
| Shrink_to n -> Shrink.int n >|= fun n -> Shrink_to n
| Set (n, c) ->
Shrink.int n
>|= (fun n -> Set (n, c))
<+> (Shrink.char c >|= fun c -> Set (n, c)))
let arb =
make gen ~print:(Print.list str_op)
~shrink:Shrink.(filter is_valid @@ list ~shrink:shrink_op)
exception Nope of string
let prop_consistent ops =
let buf = ref "" in
let b = create ~cap:32 () in
let run_op op =
match op with
| Get i ->
assert (String.length !buf = length b);
let c1 = !buf.[i] in
let c2 = get b i in
if c1 <> c2 then raise (Nope (spf "c1=%C, c2=%C" c1 c2))
| Get_contents ->
let s1 = !buf in
let s2 = contents b in
if s1 <> s2 then raise (Nope (spf "s1=%S, s2=%S" s1 s2))
| Add_char c ->
buf := !buf ^ String.make 1 c;
add_char b c
| Add_string s ->
buf := !buf ^ s;
append_string b s
| Clear ->
buf := "";
clear b
| Shrink_to n ->
buf := String.sub !buf 0 n;
shrink_to b n
| Set (n, c) ->
(let b' = Bytes.of_string !buf in
Bytes.set b' n c;
buf := Bytes.unsafe_to_string b');
set b n c
in
assume (is_valid ops);
try
List.iter run_op ops;
true
with Nope str -> Test.fail_reportf "consistent ops failed:\n%s" str
;;
q arb (fun ops -> prop_consistent ops)