fix(ocamllsp): use Spawn to launch ppx

Signed-off-by: Rudi Grinberg <[email protected]>

ps-id: 3a6f3b4e-0d69-4730-aaa1-c301cae5e9c3

Author: rgrinberg

ocaml-lsp-server/vendor/merlin/src/kernel/dune

@@ -14,7 +14,7 @@
   -open Merlin_specific
   -open Merlin_extend)
  (libraries merlin_config os_ipc ocaml_parsing ocaml_preprocess ocaml_typing ocaml_utils
-            merlin_extend merlin_specific merlin_utils merlin_dot_protocol))
+            merlin_extend merlin_specific merlin_utils merlin_dot_protocol spawn))
 
 (rule
   (targets standard_library.ml)

ocaml-lsp-server/vendor/merlin/src/ocaml/driver/pparse.ml

@@ -46,7 +46,19 @@ let merlin_system_command =
     windows_merlin_system_command
   else
     fun cmd ~cwd ->
-      Sys.command (Printf.sprintf "cd %s && %s" (Filename.quote cwd) cmd)
+      let prog = "/bin/bash" in
+      let argv = ["sh"; "-c"; cmd] in
+      let stdin = Unix.openfile "/dev/null" [ Unix.O_RDONLY ] 0x777  in
+      let pid = Spawn.spawn ~prog ~argv ~stdin ~stdout:Unix.stderr ~stderr:Unix.stderr () in
+      let (_, status) = Unix.waitpid [] pid in
+      let res =
+        match (status : Unix.process_status) with
+        | WEXITED n -> n
+        | WSIGNALED _ -> -1
+        | WSTOPPED _ -> -1
+      in
+      Unix.close stdin;
+      res
 
 let ppx_commandline cmd fn_in fn_out =
   Printf.sprintf "%s %s %s%s"