flan/test/test_acceptance.ml
Joseph Ferano 18db822095 error, which is the signal a handler has to answer
spec-conditions.md §2. The same lookup as signal, and the difference is
entirely what happens when the walk ends: signal returns Unit and the
signalling function carries on, error has type Never and the program stops.
Only a transfer gets past it, so emit puts a guard after the call and then
unreachable - and flan_error cannot be marked noreturn for the same reason, it
does return, on exactly one path.

Being Never is what lets it stand where a value was expected, which is the
fall-through shape §1's load-texture example needs and the reason it is worth
having before the break loop rather than after. An unhandled one names the
condition on stderr and dies the way every other trap does; flan_error is where
the dev-build break loop will go.

The two spellings share one AST and IR node with a kind beside them, the same
shape Ast.unwrap already uses for some and try, because they differ in one
decision and nothing else. test/programs/error.flan is the unhandled case,
asserted on the exit code and the reason rather than through the outputs table,
which only has room for a program that exits 0.
2026-09-11 09:10:59 +07:00

250 lines
11 KiB
OCaml

(* The milestone-2 acceptance test: a table of expression/result pairs run
through a compiled calc-me (plan.org, Build sequence).
It is a table rather than a golden file because milestone 3 runs the *same*
table on wasm32 — headless is what makes one test cover both targets. *)
open Flan
let failures = ref 0
let scratch = Filename.get_temp_dir_name ()
let run exe arg =
let out = Filename.concat scratch "flan-acceptance.out" in
let cmd =
Printf.sprintf "%s %s > %s 2>&1"
(Filename.quote exe)
(match arg with None -> "" | Some a -> Filename.quote a)
(Filename.quote out)
in
let code = Sys.command cmd in
let text = In_channel.with_open_bin out In_channel.input_all in
Sys.remove out;
(code, text)
let compile ?(opt = "-O2") ?(checks = true) ?(dev = false) path =
let exe =
Filename.concat scratch
("flan-t-" ^ Filename.remove_extension (Filename.basename path))
in
(* Through [Load], so a program with an (import ...) is buildable here: it
brings back the package's C shim and linker arguments as well. *)
let l = Load.program ~file:path (Parse.program (Reader.read_file path)) in
let p = Check.program l.Load.decls in
ignore (Build.executable ~opts:{ Build.default with opt; checks; dev }
~csrcs:l.Load.csrcs ~lflags:l.Load.lflags p ~out:exe);
exe
(* No Str, and the reader is hand-written for the same reason. *)
let contains hay needle =
let n = String.length needle and h = String.length hay in
let rec go i = i + n <= h && (String.sub hay i n = needle || go (i + 1)) in
go 0
let () =
match Sys.command "command -v clang > /dev/null 2>&1" with
| 0 ->
let exe = compile "../calc-me.flan" in
let case name arg expected_out expected_code =
let code, text = run exe arg in
if text <> expected_out || code <> expected_code then begin
incr failures;
Printf.printf
"FAIL %s\n got: %S (exit %d)\n wanted: %S (exit %d)\n"
name text code expected_out expected_code
end
in
let evaluates src expected = case src (Some src) (expected ^ "\n") 0 in
let rejects src = case src (Some src) "calc-me: cannot parse\n" 1 in
(* Arithmetic and precedence *)
evaluates "1 + 2 * (3 - 0.5) / 2" "3.5";
evaluates "1+2*3" "7";
evaluates "2*3+4" "10";
evaluates "(1+2)*3" "9";
evaluates "10/4" "2.5";
evaluates "7" "7";
evaluates " 7 " "7";
evaluates "1.5+2.25" "3.75";
(* Left-associative: 1-2-3 is (1-2)-3, not 1-(2-3) *)
evaluates "1-2-3" "-4";
evaluates "8/4/2" "1";
(* Unary minus, including nested *)
evaluates "-5" "-5";
evaluates "-(1+2)" "-3";
evaluates "3 * -2" "-6";
(* Whole input or nothing: trailing junk is an error, not ignored *)
rejects "1 +";
rejects "(1+2";
rejects "1 2";
rejects "";
rejects "+";
rejects "1+2)";
case "no argument" None "usage: calc-me \"1 + 2 * 3\"\n" 1;
(try Sys.remove exe with Sys_error _ -> ());
(* Programs whose whole output is fixed. These cover the milestone-2
surface calc-me does not reach — globals, 2-D arrays, places through a
pointer, casts, match with either arm taken, and the value semantics of
spec-memory.md. *)
let outputs ?opt ?dev name path expected =
let exe = compile ?opt ?dev path in
let code, text = run exe None in
if text <> expected || code <> 0 then begin
incr failures;
Printf.printf
"FAIL %s\n got: %S (exit %d)\n wanted: %S (exit 0)\n"
name text code expected
end;
(try Sys.remove exe with Sys_error _ -> ())
in
let values_out = "1\n5\nel\n" in
let machine_out = "12\n30\n2\n2\n3\n3.5\n42\n99\n12\n123\n" in
outputs "value semantics" "programs/values.flan" values_out;
outputs "machine surface" "programs/machine.flan" machine_out;
outputs "unit main exits 0" "programs/unit-main.flan" "ok\n";
(* handler-bind and signal, spec-conditions.md §1 and §2: signal returns
Unit and carries on, an unhandled one is a no-op, a nested frame does
not displace the one outside it, and the stack is restored after. *)
let conditions_out = "0\n3\n23\n3\n1103\n1103\n" in
outputs "conditions" "programs/conditions.flan" conditions_out;
outputs ~opt:"-O0" "conditions, -O0" "programs/conditions.flan" conditions_out;
outputs ~dev:true "conditions, dev" "programs/conditions.flan" conditions_out;
(* restart-case and invoke-restart, §3 to §6: the transfer itself. A
fall-through with nothing handling it, a clause reached from two frames
down, the defer in between running on the way out, an inner frame
shadowing an outer one of the same name, and a handler that returns
normally still transferring nothing. At -O0 as well, because the guard
after every call is control flow the optimiser would otherwise launder;
and as a dev build, where every one of those calls goes through a cell. *)
let restarts_out = "101\n1\n-1\n2\n7\n1010\n101\n105\n-2\n" in
outputs "restarts" "programs/restarts.flan" restarts_out;
outputs ~opt:"-O0" "restarts, -O0" "programs/restarts.flan" restarts_out;
outputs ~dev:true "restarts, dev" "programs/restarts.flan" restarts_out;
(* §2's other half, which cannot be an [outputs] case because it does not
exit 0: a handler runs, returns normally, and has still not answered the
error, so the program stops and names the condition. *)
let exe = compile "programs/error.flan" in
let code, text = run exe None in
if code <> 134 || not (contains text "handler ran")
|| not (contains text "unhandled AssetMissing")
then begin
incr failures;
Printf.printf
"FAIL an unhandled error stops the program\n\
\ got: %S (exit %d)\n wanted: exit 134, naming the condition\n"
text code
end;
(* The raylib FFI, headless. GetColor and the enums need no window, so the
whole boundary is exercised without a display: a struct returned through
an out-pointer, a keyword resolved against an enum, and a Flan string
crossing as ptr+len. 0x11223344 comes back as four separate bytes, which
is the check that matters — a Color is not the little-endian reading of
the packed integer, so an identity would pass a weaker test. *)
if Sys.command "ldconfig -p 2>/dev/null | grep -q libraylib" = 0 then
outputs "raylib ffi, headless" "programs/raylib-ffi.flan" "17\n34\n51\n68\n"
else
print_endline "acceptance: skipping the raylib FFI case (no libraylib)";
(* Again at -O0. Everything above runs through mem2reg, which launders a
sloppy alloca; -O0 tests the IR actually emitted, so a disagreement
between the two points at undefined behaviour rather than a typo. *)
(* sand.flan's simulation, headless. This is the milestone-4 acceptance
case: N frames from a seeded PRNG, one hash. It imports the sim package
and not raylib, deliberately — a program that imports raylib links
libraylib on every target, and this one is the version meant to run on
wasm32 too. The hash is reproducible only because rand-f32 is ours. *)
let sand_out = "2256461126764447066\n" in
outputs "sand, headless" "programs/sand-headless.flan" sand_out;
outputs ~opt:"-O0" "sand, headless, -O0" "programs/sand-headless.flan" sand_out;
outputs ~opt:"-O0" "value semantics, -O0" "programs/values.flan" values_out;
outputs ~opt:"-O0" "machine surface, -O0" "programs/machine.flan" machine_out;
(* And once more as a dev build. Every call in one goes through a cell, so
this is the same table asserting the indirection changes nothing before
anything has been redefined — the sand hash especially, since it is the
one result that would notice a call reaching the wrong function. *)
outputs ~dev:true "sand, headless, dev" "programs/sand-headless.flan" sand_out;
outputs ~dev:true "value semantics, dev" "programs/values.flan" values_out;
outputs ~dev:true "machine surface, dev" "programs/machine.flan" machine_out;
(* Bounds checks, NEXT.md item 2. A trap has no result — it has a nonzero
exit and a message on stderr — so it needs a case shape the table above
does not have. What is asserted is the *reason*: the location, and which
index against which length. The line and column are not pinned, because
editing the program should not break the test that reads it. *)
let bounds ?opt () =
let exe = compile ?opt "programs/bounds.flan" in
let traps name arg reason =
let code, text = run exe (Some arg) in
if code <> 134
|| not (contains text "programs/bounds.flan:")
|| not (contains text reason)
then begin
incr failures;
Printf.printf
"FAIL %s\n got: %S (exit %d)\n wanted: %S (exit 134)\n"
name text code reason
end
in
(* Both edges are in bounds and must not trap: the last index of a fixed
array, a slice ending exactly at len, and an empty slice at len. *)
let code, text = run exe (Some "0") in
if text <> "0ello\n" || code <> 0 then begin
incr failures;
Printf.printf "FAIL in-bounds edges\n got: %S (exit %d)\n" text code
end;
traps "at past a fixed array" "3"
"index 3 is out of bounds for length 3";
(* Negative indices sext to a huge unsigned, so the one unsigned
comparison catches them; the message still reports the signed value. *)
traps "at with a negative index" "-1"
"index -1 is out of bounds for length 3";
traps "at past a slice" "9"
"index 9 is out of bounds for length 5";
(* A different lowering — place/Pindex, not At — so it is its own case. *)
traps "set past a fixed array" "7"
"index 7 is out of bounds for length 3";
traps "slice with hi past len" "4"
"slice [4 9) is out of bounds for length 5";
(* Without the lo <= hi test this one would not trap: it would build a
slice of length hi - lo as a huge unsigned, which is worse. *)
traps "slice with a reversed range" "2"
"slice [2 1) is out of bounds for length 5";
(try Sys.remove exe with Sys_error _ -> ())
in
bounds ();
bounds ~opt:"-O0" ();
(* The release build drops them — the calls, that is; the two declarations
stay in the header and LLVM discards the unused ones. Asserted on the IR
rather than by running an unchecked out-of-bounds program, which has no
defined behaviour to assert on. *)
let p =
Reader.read_file "programs/bounds.flan" |> Parse.program |> Check.program
in
if not (contains (Emit.program p) "call void @flan_bounds_fail(") then begin
incr failures;
print_endline "FAIL checks on: no bounds call emitted"
end;
let off = Emit.program ~checks:false p in
if contains off "call void @flan_bounds_fail(" || contains off "call void @flan_slice_fail(" then begin
incr failures;
print_endline "FAIL --no-bounds-checks: a check survived"
end;
if !failures = 0 then print_endline "acceptance: all tests passed"
else begin
Printf.printf "\n%d failure(s)\n" !failures;
exit 1
end
| _ -> print_endline "acceptance: skipped (no clang on PATH)"