TypeScript codegen backend

.gitignore

@@ -44,14 +44,16 @@ _build_playground
 .idea
 .DS_Store
 
-node_modules
+**/node_modules/
+!tests/build_tests/*/node_modules/
 *.dump
 coverage
 
 .ninja_log
 .bsdeps
 .bsbuild
 lib/ocaml
+/lib/
 tests/build_tests/*/lib/
 #ignore temporary directory
 *.goog.js

compiler/bsb/bsb_config_parse.ml

@@ -283,6 +283,14 @@ let interpret_json ~(filename : string) ~(json : Ext_json_types.t)
         | Dependency x -> ({jsx with version = x.jsx.version}, bsc_flags)
         | Toplevel -> (jsx, bsc_flags)
       in
+      let language : Bsb_spec_set.language =
+        match package_kind with
+        | Dependency x -> x.language
+        | Toplevel -> (
+          match map.?(Bsb_build_schemas.language) with
+          | Some (Str {str = "typescript"}) -> Typescript
+          | Some _ | None -> Javascript)
+      in
       {
         gentype_config;
         package_name;
@@ -308,13 +316,15 @@ let interpret_json ~(filename : string) ~(json : Ext_json_types.t)
         js_post_build_cmd = extract_js_post_build map per_proj_dir;
         package_specs =
           (match package_kind with
-          | Toplevel -> Bsb_package_specs.from_map ~cwd:per_proj_dir map
+          | Toplevel ->
+            Bsb_package_specs.from_map ~cwd:per_proj_dir ~language map
           | Dependency x -> x.package_specs);
         file_groups = groups;
         files_to_install = Queue.create ();
         jsx;
         generators = extract_generators map;
         cut_generators;
+        language;
         filename;
       }
     | None -> Bsb_exception.invalid_spec ("no sources specified in " ^ filename)
@@ -323,8 +333,15 @@ let interpret_json ~(filename : string) ~(json : Ext_json_types.t)
 
 let deps_from_bsconfig () =
   let cwd = Bsb_global_paths.cwd in
+  let ( .?() ) = Map_string.find_opt in
   match
     Bsb_config_load.load_json ~per_proj_dir:cwd ~warn_legacy_config:false
   with
-  | _, Obj {map} -> (Bsb_package_specs.from_map ~cwd map, Bsb_jsx.from_map map)
+  | _, Obj {map} ->
+    let language : Bsb_spec_set.language =
+      match map.?(Bsb_build_schemas.language) with
+      | Some (Str {str = "typescript"}) -> Typescript
+      | Some _ | None -> Javascript
+    in
+    (Bsb_package_specs.from_map ~cwd ~language map, Bsb_jsx.from_map map)
   | _, _ -> assert false

compiler/bsb/bsb_config_types.ml

@@ -29,6 +29,7 @@ type dependencies = dependency list
 type gentype_config = bool
 type command = string
 type ppx = {name: string; args: string list}
+type language = Bsb_spec_set.language = Javascript | Typescript
 
 type t = {
   package_name: string;
@@ -56,5 +57,6 @@ type t = {
   cut_generators: bool;
   (* note when used as a dev mode, we will always ignore it *)
   gentype_config: gentype_config;
+  language: language;
   filename: string;
 }

compiler/bsb/bsb_ninja_gen.ml

@@ -153,6 +153,8 @@ let output_ninja_and_namespace_map ~per_proj_dir ~package_kind
        namespace;
        warning;
        gentype_config;
+       language;
+       filename = _;
      } :
       Bsb_config_types.t) : unit =
   let lib_artifacts_dir = Bsb_config.lib_bs in
@@ -197,7 +199,7 @@ let output_ninja_and_namespace_map ~per_proj_dir ~package_kind
       ~dpkg_incls (* dev dependencies *)
       ~lib_incls (* its own libs *)
       ~dev_incls (* its own devs *)
-      generators
+      ~language generators
   in
 
   let oc = open_out_bin (cwd_lib_bs // Literals.build_ninja) in

compiler/bsb/bsb_ninja_rule.ml

@@ -92,7 +92,8 @@ let make_custom_rules ~(gentype_config : Bsb_config_types.gentype_config)
     ~(namespace : string option) ~package_name ~warnings
     ~(ppx_files : Bsb_config_types.ppx list) ~bsc_flags ~(dpkg_incls : string)
     ~(lib_incls : string) ~(dev_incls : string)
-    (custom_rules : command Map_string.t) : builtin =
+    ~(language : Bsb_spec_set.language) (custom_rules : command Map_string.t) :
+    builtin =
   let bs_dep = Ext_filename.maybe_quote Bsb_global_paths.vendor_bsdep in
   let bsc = Ext_filename.maybe_quote Bsb_global_paths.vendor_bsc in
   (* FIXME: We don't need set [-o ${out}] when building ast
@@ -122,6 +123,9 @@ let make_custom_rules ~(gentype_config : Bsb_config_types.gentype_config)
     (match gentype_config with
     | false -> ()
     | true -> Ext_buffer.add_string buf " -bs-gentype");
+    (match language with
+    | Bsb_spec_set.Typescript -> Ext_buffer.add_string buf " -bs-typescript"
+    | Bsb_spec_set.Javascript -> ());
     if read_cmi <> `is_cmi then (
       Ext_buffer.add_string buf " -bs-package-name ";
       Ext_buffer.add_string buf (Ext_filename.maybe_quote package_name);

compiler/bsb/bsb_ninja_rule.mli

@@ -79,5 +79,6 @@ val make_custom_rules :
   dpkg_incls:string ->
   lib_incls:string ->
   dev_incls:string ->
+  language:Bsb_spec_set.language ->
   command Map_string.t ->
   builtin

compiler/bsb/bsb_package_kind.ml

@@ -22,7 +22,11 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)
 
-type dep_payload = {package_specs: Bsb_package_specs.t; jsx: Bsb_jsx.t}
+type dep_payload = {
+  package_specs: Bsb_package_specs.t;
+  jsx: Bsb_jsx.t;
+  language: Bsb_spec_set.language;
+}
 
 type t = Toplevel | Dependency of dep_payload
 (* This package specs comes from the toplevel to

compiler/bsb/bsb_package_specs.ml

@@ -65,9 +65,9 @@ let string_of_format (x : Ext_module_system.t) =
   | Esmodule -> Literals.esmodule
   | Es6_global -> Literals.es6_global
 
-let js_suffix_regexp = Str.regexp "[A-Za-z0-9-_.]*\\.[cm]?js"
+let suffix_regexp = Str.regexp "[A-Za-z0-9-_.]*\\.[cm]?[jt]s"
 
-let validate_js_suffix suffix = Str.string_match js_suffix_regexp suffix 0
+let validate_suffix suffix = Str.string_match suffix_regexp suffix 0
 
 let rec from_array suffix (arr : Ext_json_types.t array) : Spec_set.t =
   let spec = ref Spec_set.empty in
@@ -98,16 +98,15 @@ and from_json_single suffix (x : Ext_json_types.t) : Bsb_spec_set.spec =
       in
       let suffix =
         match map.?(Bsb_build_schemas.suffix) with
-        | Some (Str {str = suffix; _}) when validate_js_suffix suffix -> suffix
+        | Some (Str {str = suffix; _}) when validate_suffix suffix -> suffix
         | Some (Str {str; loc}) ->
           Bsb_exception.errorf ~loc
-            "invalid suffix \"%s\". The suffix and may contain letters, \
-             digits, \"-\", \"_\" and \".\" and must end with .js, .mjs or \
-             .cjs."
+            "invalid suffix \"%s\". The suffix must end with .js, .mjs, .cjs, \
+             .ts, .mts, or .cts."
             str
         | Some _ ->
           Bsb_exception.errorf ~loc:(Ext_json.loc_of x)
-            "expected a string extension like \".js\""
+            "expected a string extension like \".js\" or \".ts\""
         | None -> suffix
       in
       {format = supported_format format loc; in_source; suffix}
@@ -192,20 +191,26 @@ let list_dirs_by (package_specs : t) (f : string -> unit) =
 
 type json_map = Ext_json_types.t Map_string.t
 
-let extract_js_suffix_exn (map : json_map) : string =
+let extract_suffix_exn ~(language : Bsb_spec_set.language) (map : json_map) :
+    string =
+  let default_suffix =
+    match language with
+    | Bsb_spec_set.Javascript -> Literals.suffix_js
+    | Bsb_spec_set.Typescript -> Literals.suffix_ts
+  in
   match map.?(Bsb_build_schemas.suffix) with
-  | None -> Literals.suffix_js
-  | Some (Str {str = suffix; _}) when validate_js_suffix suffix -> suffix
+  | None -> default_suffix
+  | Some (Str {str = suffix; _}) when validate_suffix suffix -> suffix
   | Some (Str {str; _} as config) ->
     Bsb_exception.config_error config
       ("invalid suffix \"" ^ str
-     ^ "\". The suffix and may contain letters, digits, \"-\", \"_\" and \".\" \
-        and must end with .js, .mjs or .cjs.")
+     ^ "\". The suffix must end with .js, .mjs, .cjs, .ts, .mts, or .cts.")
   | Some config ->
-    Bsb_exception.config_error config "expected a string extension like \".js\""
+    Bsb_exception.config_error config
+      "expected a string extension like \".js\" or \".ts\""
 
-let from_map ~(cwd : string) map =
-  let suffix = extract_js_suffix_exn map in
+let from_map ~(cwd : string) ~(language : Bsb_spec_set.language) map =
+  let suffix = extract_suffix_exn ~language map in
   let modules =
     match map.?(Bsb_build_schemas.package_specs) with
     | Some x -> from_json suffix x

compiler/bsb/bsb_package_specs.mli

@@ -24,7 +24,11 @@
 
 type t
 
-val from_map : cwd:string -> Ext_json_types.t Map_string.t -> t
+val from_map :
+  cwd:string ->
+  language:Bsb_spec_set.language ->
+  Ext_json_types.t Map_string.t ->
+  t
 
 val get_list_of_output_js : t -> string -> string list
 

compiler/bsb/bsb_spec_set.ml

@@ -27,6 +27,8 @@
 (* TODO: sync up with {!Js_packages_info.module_system}  *)
 type format = Ext_module_system.t
 
+type language = Javascript | Typescript
+
 type spec = {format: format; in_source: bool; suffix: string}
 
 type t = spec list

compiler/bsb/bsb_spec_set.mli

@@ -23,6 +23,8 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)
 type format = Ext_module_system.t
 
+type language = Javascript | Typescript
+
 type spec = {format: format; in_source: bool; suffix: string}
 
 type t = private spec list

compiler/bsb/bsb_world.ml

@@ -27,15 +27,16 @@ let vendor_ninja = Bsb_global_paths.vendor_ninja
 
 let make_world_deps cwd (config : Bsb_config_types.t option)
     (ninja_args : string array) =
-  let package_specs, jsx =
+  let package_specs, jsx, language =
     match config with
     | None ->
       (* When this running bsb does not read rescript.json,
          we will read such json file to know which [package-specs]
          it wants
       *)
-      Bsb_config_parse.deps_from_bsconfig ()
-    | Some config -> (config.package_specs, config.jsx)
+      let package_specs, jsx = Bsb_config_parse.deps_from_bsconfig () in
+      (package_specs, jsx, Bsb_spec_set.Javascript)
+    | Some config -> (config.package_specs, config.jsx, config.language)
   in
   let args =
     if Ext_array.is_empty ninja_args then [|vendor_ninja|]
@@ -64,7 +65,7 @@ let make_world_deps cwd (config : Bsb_config_types.t option)
            Bsb_build_util.mkp lib_bs_dir;
            let _config : _ option =
              Bsb_ninja_regen.regenerate_ninja
-               ~package_kind:(Dependency {package_specs; jsx})
+               ~package_kind:(Dependency {package_specs; jsx; language})
                ~per_proj_dir:proj_dir ~forced:false ~warn_legacy_config:false
                ~warn_as_error:None
            in

compiler/bsc/rescript_compiler_main.ml

@@ -259,6 +259,12 @@ let command_line_flags : (string * Bsc_args.spec * string) array =
       string_call ignore,
       "*internal* Set jsx mode, this is no longer used and is a no-op." );
     ("-bs-jsx-preserve", set Js_config.jsx_preserve, "*internal* Preserve jsx");
+    ( "-bs-typescript",
+      unit_call (fun _ -> Js_config.ts_output := Js_config.Ts_typescript),
+      "*internal* Generate TypeScript output with type annotations" );
+    ( "-bs-emit-dts",
+      unit_call (fun _ -> Js_config.emit_dts := true),
+      "*internal* Emit .d.ts declaration files alongside JavaScript output" );
     ( "-bs-package-output",
       string_call Js_packages_state.update_npm_package_path,
       "*internal* Set npm-output-path: [opt_module]:path, for example: \

compiler/common/js_config.ml

@@ -72,3 +72,13 @@ let jsx_module_of_string = function
 
 let as_pp = ref false
 let self_stack : string Stack.t = Stack.create ()
+
+(** TypeScript output mode *)
+type ts_output_mode =
+  | Ts_none  (** Plain JavaScript output (default) *)
+  | Ts_typescript  (** Full TypeScript output (.ts) *)
+
+let ts_output = ref Ts_none
+
+(** Whether to emit .d.ts declaration files *)
+let emit_dts = ref false

compiler/common/js_config.mli

@@ -101,3 +101,13 @@ val jsx_module_of_string : string -> jsx_module
 val as_pp : bool ref
 
 val self_stack : string Stack.t
+
+(** TypeScript output mode *)
+type ts_output_mode =
+  | Ts_none  (** Plain JavaScript output (default) *)
+  | Ts_typescript  (** Full TypeScript output (.ts) *)
+
+val ts_output : ts_output_mode ref
+
+val emit_dts : bool ref
+(** Whether to emit .d.ts declaration files *)

compiler/core/j.ml

@@ -138,6 +138,7 @@ and expression_desc =
       return_unit: bool;
       async: bool;
       directive: string option;
+      fn_type: Types.type_expr option;
     }
   | Str of {delim: delim; txt: string}
   (* A string is UTF-8 encoded, and may contain
@@ -293,13 +294,23 @@ and variable_declaration = {
   value: expression option;
   property: property;
   ident_info: ident_info;
+  ident_type: Types.type_expr option;
+      (** Type annotation for TypeScript output *)
 }
 
 (* TODO: For efficency: block should not be a list, it should be able to
    be concatenated in both ways
 *)
 and block = statement list
-and program = {block: block; exports: exports; export_set: Set_ident.t}
+and program = {
+  block: block;
+  exports: exports;
+  export_set: Set_ident.t;
+  type_exports: Ts.type_decl list;
+      (** Exported type declarations for TypeScript output *)
+  value_exports: Ts.value_export list;
+      (** Exported values with types for .d.ts generation *)
+}
 
 and deps_program = {
   program: program;