Vendor Flow parser 0.267.0 (#8587)

* Vendor Flow parser 0.267.0

Signed-off-by: Christoph Knittel <ck@cca.io>

* Add Flow parser vendoring changelog entry

Signed-off-by: Christoph Knittel <ck@cca.io>

---------

Signed-off-by: Christoph Knittel <ck@cca.io>

Author: cknitt

.ocamlformat-ignore

@@ -0,0 +1 @@
+compiler/flow_parser/**

CHANGELOG.md

@@ -57,6 +57,7 @@
 
 #### :house: Internal
 
+- Vendor the Flow parser 0.267.0 sources used by the compiler, removing the external `flow_parser` dependency and establishing a maintained baseline for future OCaml upgrades. https://github.com/rescript-lang/rescript/pull/8587
 - Store processed external declarations as structured data instead of serialized values in `pval_prim`, and lower external calls during Lambda translation. This removes `Pccall`, `external_spec`, and the unsupported `%absfloat` primitive. The AST, CMI, and CMT magic numbers are bumped (`ResImpl01301`/`ResIntf01301`, `Caml1999I025`, `Caml1999T026`). https://github.com/rescript-lang/rescript/pull/8581
 - Resolve dynamic-import targets during Lambda translation and store the module and export path directly in `Pimport`. This removes the `dynamic_import` flags from `Pjs_call` and `Lglobal_module`, along with backend expression-shape detection. https://github.com/rescript-lang/rescript/pull/8582
 - Give nominal variants one canonical runtime layout: compute their JavaScript representation once after typing each declaration, replace positional constructor tags with semantic runtime descriptors, and make construction, matching, coercion, printing, diagnostics, and GenType consume the stored representation instead of reinterpreting annotations. Pattern matching keeps occurrence-specific plans local without adding another Lambda or Lam expression form. https://github.com/rescript-lang/rescript/pull/8579

compiler/flow_parser/LICENSE

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+MIT License
+
+Copyright (c) Meta Platforms, Inc. and affiliates.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

compiler/flow_parser/README.md

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+# Vendored Flow parser
+
+This directory contains the OCaml Flow parser used by the ReScript compiler.
+
+- Upstream fork: https://github.com/rescript-lang/flow
+- Flow parser version: `0.267.0`
+- Source commit: `9ea4062c0b7e037415c4413a7634c459ebd5c31b`
+- Original source directories: `src/parser`, `src/third-party/sedlex`,
+  `src/third-party/sedlex-ppx`, and `src/hack_forked/utils/collections`
+
+The Dune files were adapted to build these sources as private libraries inside
+the ReScript repository. Sources used only by the upstream JavaScript and C API
+targets are not included. One ambiguous Sedlex documentation comment was
+converted to a regular comment so the vendored sources build with ReScript's
+warning settings.
+
+Vendored sources are excluded from the repository-wide OCamlformat check so
+that they remain comparable with their upstream versions.
+
+The Flow sources are licensed under the MIT licence in `LICENSE`. Vendored
+Sedlex and collections sources retain their own licence files.

compiler/flow_parser/collections/dune

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+(include_subdirs unqualified)
+
+(library
+ (name collections)
+ (wrapped false)
+ (libraries base))

compiler/flow_parser/collections/iMap.ml

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+(*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+include WrappedMap.Make (IntKey)
+
+let pp : (Format.formatter -> 'a -> unit) -> Format.formatter -> 'a t -> unit =
+ (fun pp_data -> make_pp IntKey.pp pp_data)
+
+let show pp_data x = Format.asprintf "%a" (pp pp_data) x

compiler/flow_parser/collections/iSet.ml

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+(*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+include Flow_set.Make (IntKey)
+
+let pp = make_pp IntKey.pp
+
+let show iset = Format.asprintf "%a" pp iset
+
+let to_string = show

compiler/flow_parser/collections/immQueue.ml

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+(*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+type 'a t = {
+  incoming: 'a list;
+  outgoing: 'a list;
+  length: int;
+}
+
+let empty = { incoming = []; outgoing = []; length = 0 }
+
+let length t = t.length
+
+let is_empty t = length t = 0
+
+let push t x = { t with incoming = x :: t.incoming; length = t.length + 1 }
+
+let prepare_for_read t =
+  match t.outgoing with
+  | [] -> { t with incoming = []; outgoing = List.rev t.incoming }
+  | _ -> t
+
+let pop t =
+  let t = prepare_for_read t in
+  match t.outgoing with
+  | [] -> (None, t)
+  | hd :: tl -> (Some hd, { t with outgoing = tl; length = t.length - 1 })
+
+let peek t =
+  let t = prepare_for_read t in
+  match t.outgoing with
+  | [] -> (None, t)
+  | hd :: _ -> (Some hd, t)
+
+let exists t ~f = List.exists f t.outgoing || List.exists f t.incoming
+
+let iter t ~f =
+  List.iter f t.outgoing;
+  List.iter f (List.rev t.incoming)
+
+let from_list x = { incoming = []; outgoing = x; length = List.length x }
+
+let to_list x = x.outgoing @ List.rev x.incoming
+
+let concat t =
+  {
+    incoming = [];
+    outgoing = Base.List.concat_map ~f:to_list t;
+    length = List.map (fun u -> u.length) t |> List.fold_left ( + ) 0;
+  }

compiler/flow_parser/collections/immQueue.mli

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+(*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+(*
+ * Immutable queue implementation. Modeled loosely after the mutable stdlib
+ * Queue. push, pop, etc. are amortized O(1).
+ *)
+
+type 'a t
+
+val empty : 'a t
+
+val push : 'a t -> 'a -> 'a t
+
+val pop : 'a t -> 'a option * 'a t
+
+val peek : 'a t -> 'a option * 'a t
+
+val is_empty : 'a t -> bool
+
+val length : 'a t -> int
+
+val exists : 'a t -> f:('a -> bool) -> bool
+
+val iter : 'a t -> f:('a -> unit) -> unit
+
+(* from_list: the head of the list is the first one to be popped *)
+val from_list : 'a list -> 'a t
+
+(* to_list: the head of the list is the first one to be popped *)
+val to_list : 'a t -> 'a list
+
+val concat : 'a t list -> 'a t

compiler/flow_parser/collections/intKey.ml

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+(*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+type t = int
+
+let compare = ( - )
+
+let pp = Format.pp_print_int