Simplify code to un-shadow the stdlib Unix module

Summary:
Per feedback from Pradeep, the previous code to save the stdlib Unix module to a
temporary name, then restore the shadowed-by-Core module after was confusing.

This diff takes a different approach, which saves the original module to
CamlUnix, but does not then restore the "original" Unix module and just leaves
Core's override.

Reviewed By: connernilsen

Differential Revision: D50150099

fbshipit-source-id: 1af14175138658c2ef0841087758d606c3832950

source/hack_parallel/hack_parallel/utils/hh_logger.ml

@@ -8,12 +8,12 @@
 (* TODO(T132410158) Add a module-level doc comment. *)
 
 
-module Caml_unix = Unix
+(* Core shadows/deprecates the stdlib Unix module. *)
+module CamlUnix = Unix
 open Core
-module Unix = Caml_unix
 
 let timestamp_string () =
-  let open Unix in
+  let open CamlUnix in
   let tm = localtime (time ()) in
   let year = tm.tm_year + 1900 in
   Printf.sprintf "[%d-%02d-%02d %02d:%02d:%02d]"
@@ -39,7 +39,7 @@ let print fmt = Printf.ksprintf print_raw (fmt^^"\n")
 
 let print_duration name t =
   print_raw (name ^ ": ");
-  let t2 = Unix.gettimeofday() in
+  let t2 = CamlUnix.gettimeofday() in
   Printf.eprintf "%f\n%!" (t2 -. t);
   t2
 

source/log.ml

@@ -9,9 +9,8 @@
    prefixing log output with an appropriate section name *)
 
 (* Core shadows/deprecates the stdlib Unix module. *)
-module Caml_unix = Unix
+module CamlUnix = Unix
 open Core
-module Unix = Caml_unix
 
 type section =
   [ `Check
@@ -96,7 +95,7 @@ end
 let is_enabled section = Hash_set.mem GlobalState.enabled (section_to_string section)
 
 let format_tm fmt tm =
-  let open Unix in
+  let open CamlUnix in
   let year = tm.tm_year + 1900 in
   let month = tm.tm_mon + 1 in
   Format.fprintf
@@ -113,7 +112,7 @@ let format_tm fmt tm =
 let log ~section format =
   let section = section_to_string section in
   if Hash_set.mem GlobalState.enabled section then
-    let localtime = Unix.localtime (Unix.time ()) in
+    let localtime = CamlUnix.localtime (CamlUnix.time ()) in
     Format.fprintf
       Format.err_formatter
       ("%a %s " ^^ format ^^ "\n%!")
@@ -140,7 +139,7 @@ let log_unix_error ?(section = `Error) (error_kind, name, parameters) =
   log
     ~section
     "Unix error %s: %s(%s)"
-    (Unix.error_message error_kind [@alert "-deprecated"])
+    (CamlUnix.error_message error_kind [@alert "-deprecated"])
     name
     parameters
 

source/pyrePath.ml

@@ -8,9 +8,8 @@
 (* TODO(T132410158) Add a module-level doc comment. *)
 
 (* Core shadows/deprecates the stdlib Unix module. *)
-module Caml_unix = Unix
+module CamlUnix = Unix
 open Core
-module Unix = Caml_unix
 
 type path = string [@@deriving compare, show, sexp, hash]
 
@@ -29,7 +28,7 @@ let absolute = function
 
 let create_absolute ?(follow_symbolic_links = false) path =
   if follow_symbolic_links then
-    Absolute (Unix.realpath path)
+    Absolute (CamlUnix.realpath path)
   else
     Absolute path
 
@@ -59,7 +58,7 @@ let create_directory_recursively ?(permission = 0o777) path =
         match do_create (Filename.dirname path) with
         | Result.Error _ as error -> error
         | Result.Ok () ->
-            Unix.mkdir path permission;
+            CamlUnix.mkdir path permission;
             Result.Ok ())
     | path when Caml.Sys.is_directory path -> Result.Ok ()
     | path ->
@@ -107,9 +106,9 @@ let is_path_python_init path =
 
 
 let rec stat_no_eintr_raw path =
-  try Some (Unix.stat path) with
-  | Unix.Unix_error (Unix.EINTR, _, _) -> stat_no_eintr_raw path
-  | Unix.Unix_error ((Unix.ENOENT | Unix.ENOTDIR), _, _) -> None
+  try Some (CamlUnix.stat path) with
+  | CamlUnix.Unix_error (CamlUnix.EINTR, _, _) -> stat_no_eintr_raw path
+  | CamlUnix.Unix_error ((CamlUnix.ENOENT | CamlUnix.ENOTDIR), _, _) -> None
 
 
 let stat_no_eintr path = stat_no_eintr_raw (absolute path)
@@ -118,7 +117,7 @@ let file_exists path = Option.is_some (stat_no_eintr path)
 
 let directory_exists path =
   match stat_no_eintr path with
-  | Some { Unix.st_kind = Unix.S_DIR; _ } -> true
+  | Some { CamlUnix.st_kind = CamlUnix.S_DIR; _ } -> true
   | _ -> false
 
 
@@ -129,7 +128,7 @@ let last path =
 
 let follow_symbolic_link path =
   try absolute path |> create_absolute ~follow_symbolic_links:true |> Option.some with
-  | Unix.Unix_error _ -> None
+  | CamlUnix.Unix_error _ -> None
 
 
 (* Variant of Sys.readdir where names are sorted in alphabetical order *)
@@ -142,7 +141,7 @@ let read_directory_ordered_raw path =
 let list ?(file_filter = fun _ -> true) ?(directory_filter = fun _ -> true) ~root () =
   let rec list sofar path =
     match stat_no_eintr_raw path with
-    | Some { Unix.st_kind = Unix.S_DIR; _ } ->
+    | Some { CamlUnix.st_kind = CamlUnix.S_DIR; _ } ->
         if directory_filter path then (
           match read_directory_ordered_raw path with
           | entries ->
@@ -182,8 +181,8 @@ end
 let search_upwards ~target ~target_type ~root =
   let rec directory_has_target directory =
     match target_type, stat_no_eintr_raw (directory ^/ target) with
-    | FileType.Directory, Some { Unix.st_kind = Unix.S_DIR; _ }
-    | FileType.File, Some { Unix.st_kind = Unix.S_REG; _ } ->
+    | FileType.Directory, Some { CamlUnix.st_kind = CamlUnix.S_DIR; _ }
+    | FileType.File, Some { CamlUnix.st_kind = CamlUnix.S_REG; _ } ->
         Some (create_absolute directory)
     | _ ->
         let parent_directory = Filename.dirname directory in
@@ -196,34 +195,34 @@ let search_upwards ~target ~target_type ~root =
 
 
 let unlink_if_exists path =
-  try Unix.unlink (absolute path) with
-  | Unix.Unix_error ((Unix.ENOENT | Unix.ENOTDIR), _, _) -> ()
+  try CamlUnix.unlink (absolute path) with
+  | CamlUnix.Unix_error ((CamlUnix.ENOENT | CamlUnix.ENOTDIR), _, _) -> ()
 
 
 let remove_recursively path =
   let rec do_remove path =
     try
-      let stats = Unix.lstat path in
-      match stats.Unix.st_kind with
-      | Unix.S_DIR ->
+      let stats = CamlUnix.lstat path in
+      match stats.CamlUnix.st_kind with
+      | CamlUnix.S_DIR ->
           let contents = Caml.Sys.readdir path in
           List.iter (Array.to_list contents) ~f:(fun name ->
               let name = Filename.concat path name in
               do_remove name);
-          Unix.rmdir path
-      | Unix.S_LNK
-      | Unix.S_REG
-      | Unix.S_CHR
-      | Unix.S_BLK
-      | Unix.S_FIFO
-      | Unix.S_SOCK ->
-          Unix.unlink path
+          CamlUnix.rmdir path
+      | CamlUnix.S_LNK
+      | CamlUnix.S_REG
+      | CamlUnix.S_CHR
+      | CamlUnix.S_BLK
+      | CamlUnix.S_FIFO
+      | CamlUnix.S_SOCK ->
+          CamlUnix.unlink path
     with
     (* Path has been deleted out from under us - can ignore it. *)
     | Sys_error message ->
         Log.warning "Error occurred when removing %s recursively: %s" path message;
         ()
-    | Unix.Unix_error (Unix.ENOENT, _, _) -> ()
+    | CamlUnix.Unix_error (CamlUnix.ENOENT, _, _) -> ()
   in
   do_remove (absolute path)
 

source/pyreProfiling.ml

@@ -7,9 +7,9 @@
 
 (* Profiling logic for internal Pyre behaviour. *)
 
-module Caml_unix = Unix
+(* Core shadows/deprecates the stdlib Unix module. *)
+module CamlUnix = Unix
 open Core
-module Unix = Caml_unix
 module Worker = Hack_parallel.Std.Worker
 module SharedMemory = Hack_parallel.Std.SharedMemory
 
@@ -61,7 +61,7 @@ module Event = struct
 
   let create ?(timestamp = now_in_microseconds ()) ?(tags = []) ~event_type name =
     let name = String.filter ~f:Char.is_print name in
-    let pid = Unix.getpid () in
+    let pid = CamlUnix.getpid () in
     let worker_id = Worker.current_worker_id () in
     { name; worker_id; pid; event_type; timestamp; tags }
 end

source/service/memory.ml

@@ -7,9 +7,9 @@
 
 (* TODO(T132410158) Add a module-level doc comment. *)
 
-module Caml_unix = Unix
+(* Core shadows/deprecates the stdlib Unix module. *)
+module CamlUnix = Unix
 open Core
-module Unix = Caml_unix
 module Gc = Caml.Gc
 module Set = Caml.Set
 module SharedMemory = Hack_parallel.Std.SharedMemory
@@ -140,9 +140,9 @@ let prepare_saved_state_directory { Configuration.Analysis.log_directory; _ } =
   let table_path = PyrePath.create_relative ~root ~relative:"table" in
   let dependencies_path = PyrePath.create_relative ~root ~relative:"deps" in
   let () =
-    try Unix.mkdir (PyrePath.absolute root) 0o777 with
+    try CamlUnix.mkdir (PyrePath.absolute root) 0o777 with
     (* [mkdir] on MacOSX returns [EISDIR] instead of [EEXIST] if the directory already exists. *)
-    | Unix.Unix_error ((EEXIST | EISDIR), _, _) ->
+    | CamlUnix.Unix_error ((EEXIST | EISDIR), _, _) ->
         PyrePath.unlink_if_exists table_path;
         PyrePath.unlink_if_exists dependencies_path
     | e -> raise e
@@ -151,23 +151,21 @@ let prepare_saved_state_directory { Configuration.Analysis.log_directory; _ } =
 
 
 let rec waitpid_no_eintr flags pid =
-  try Unix.waitpid flags pid with
-  | Unix.Unix_error (Unix.EINTR, _, _) -> waitpid_no_eintr flags pid
+  try CamlUnix.waitpid flags pid with
+  | CamlUnix.Unix_error (EINTR, _, _) -> waitpid_no_eintr flags pid
 
 
 let run_tar arguments =
-  let open Unix in
-  let in_read, in_write = Unix.pipe ~cloexec:true () in
-  let out_read, out_write = Unix.pipe ~cloexec:true () in
-  let err_read, err_write = Unix.pipe ~cloexec:true () in
-  let pid =
-    Unix.create_process "tar" (Array.of_list ("tar" :: arguments)) in_read out_write err_write
-  in
+  let open CamlUnix in
+  let in_read, in_write = pipe ~cloexec:true () in
+  let out_read, out_write = pipe ~cloexec:true () in
+  let err_read, err_write = pipe ~cloexec:true () in
+  let pid = create_process "tar" (Array.of_list ("tar" :: arguments)) in_read out_write err_write in
   List.iter ~f:close [in_read; out_write; err_write];
   let _, process_status = waitpid_no_eintr [] pid in
   List.iter ~f:close [in_write; out_read; err_read];
   match process_status with
-  | Unix.WEXITED 0 -> ()
+  | WEXITED 0 -> ()
   | _ ->
       raise
         (TarError