fix #3852

Author: bobzhang

jscomp/common/js_config.ml

@@ -109,4 +109,6 @@ let refmt = ref None
 
 let is_reason = ref false
 
-let js_stdout = ref true
+let js_stdout = ref true
+
+let all_module_aliases = ref false

jscomp/common/js_config.mli

@@ -103,4 +103,6 @@ val jsx_version : int ref
 val refmt : string option ref
 val is_reason : bool ref 
 
-val js_stdout : bool ref 
+val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 

jscomp/core/js_implementation.ml

@@ -126,8 +126,34 @@ let get_lambda = fun
               lambda
 #end              -> lambda 
 
+
+let all_module_alias (ast : Parsetree.structure)= 
+  Ext_list.for_all ast (fun {pstr_desc} -> 
+    match pstr_desc with 
+    | Pstr_module {pmb_expr = {pmod_desc = Pmod_ident _ }} 
+      -> true 
+    | Pstr_attribute _ -> true   
+    | Pstr_eval _ 
+    | Pstr_value _ 
+    | Pstr_primitive _ 
+    | Pstr_type _ 
+    | Pstr_typext  _ 
+    | Pstr_exception _ 
+    | Pstr_module _ 
+    | Pstr_recmodule _  
+    | Pstr_modtype _
+    | Pstr_open _
+    | Pstr_class _ 
+    | Pstr_class_type _ 
+    | Pstr_include _
+    | Pstr_extension _ -> false 
+   )
+
 let after_parsing_impl ppf  outputprefix ast =
-  
+  Js_config.all_module_aliases := 
+    !Clflags.assume_no_mli =  Mli_non_exists &&
+    all_module_alias ast 
+    ;
   if !Js_config.binary_ast then
     Binary_ast.write_ast ~sourcefile:!Location.input_name 
       Ml ~output:(outputprefix ^ 

jscomp/core/lam_compile_main.ml

@@ -255,6 +255,8 @@ let compile
   |> _j "shake"
   |> ( fun (program:  J.program) -> 
       let external_module_ids : Lam_module_ident.t list = 
+        if !Js_config.all_module_aliases then []
+        else 
         let x = Lam_compile_env.get_required_modules  
             may_required_modules  
             (Js_fold_basic.calculate_hard_dependencies program.block) in 

jscomp/test/gpr_3852_alias.js

@@ -1,8 +1,7 @@
 'use strict';
 
-var Gpr_3852_effect = require("./gpr_3852_effect.js");
 
 var A = 0;
 
 exports.A = A;
-/* Gpr_3852_effect Not a pure module */
+/* No side effect */

lib/4.02.3/bsdep.ml

@@ -29759,6 +29759,8 @@ val refmt : string option ref
 val is_reason : bool ref 
 
 val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 
 end = struct
 #1 "js_config.ml"
 (* Copyright (C) 2015-2016 Bloomberg Finance L.P.
@@ -29873,6 +29875,8 @@ let refmt = ref None
 let is_reason = ref false
 
 let js_stdout = ref true
+
+let all_module_aliases = ref false
 end
 module Bs_warnings : sig 
 #1 "bs_warnings.mli"

lib/4.02.3/bsppx.ml

@@ -2649,6 +2649,8 @@ val refmt : string option ref
 val is_reason : bool ref 
 
 val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 
 end = struct
 #1 "js_config.ml"
 (* Copyright (C) 2015-2016 Bloomberg Finance L.P.
@@ -2763,6 +2765,8 @@ let refmt = ref None
 let is_reason = ref false
 
 let js_stdout = ref true
+
+let all_module_aliases = ref false
 end
 (** Interface as module  *)
 module Asttypes

lib/4.02.3/unstable/all_ounit_tests.ml

@@ -7411,6 +7411,8 @@ val refmt : string option ref
 val is_reason : bool ref 
 
 val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 
 end = struct
 #1 "js_config.ml"
 (* Copyright (C) 2015-2016 Bloomberg Finance L.P.
@@ -7525,6 +7527,8 @@ let refmt = ref None
 let is_reason = ref false
 
 let js_stdout = ref true
+
+let all_module_aliases = ref false
 end
 module Ml_binary : sig 
 #1 "ml_binary.mli"

lib/4.02.3/unstable/bspack.ml

@@ -8178,6 +8178,8 @@ val refmt : string option ref
 val is_reason : bool ref 
 
 val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 
 end = struct
 #1 "js_config.ml"
 (* Copyright (C) 2015-2016 Bloomberg Finance L.P.
@@ -8292,6 +8294,8 @@ let refmt = ref None
 let is_reason = ref false
 
 let js_stdout = ref true
+
+let all_module_aliases = ref false
 end
 module Ml_binary : sig 
 #1 "ml_binary.mli"

lib/4.02.3/unstable/js_compiler.ml

@@ -11709,6 +11709,8 @@ val refmt : string option ref
 val is_reason : bool ref 
 
 val js_stdout : bool ref 
+
+val all_module_aliases : bool ref 
 end = struct
 #1 "js_config.ml"
 (* Copyright (C) 2015-2016 Bloomberg Finance L.P.
@@ -11823,6 +11825,8 @@ let refmt = ref None
 let is_reason = ref false
 
 let js_stdout = ref true
+
+let all_module_aliases = ref false
 end
 module Bs_warnings : sig 
 #1 "bs_warnings.mli"
@@ -112598,7 +112602,10 @@ let prim = Lam.prim
 type required_modules = Lam_module_ident.Hash_set.t
 
 
-(** drop Lseq (List! ) etc *)
+(** drop Lseq (List! ) etc 
+  see #3852, we drop all these required global modules
+  but added it back based on our own module analysis
+*)
 let rec drop_global_marker (lam : Lam.t) =
   match lam with
   | Lsequence (Lglobal_module id, rest) ->
@@ -116270,20 +116277,19 @@ let compile
   |> Js_shake.shake_program
   |> _j "shake"
   |> ( fun (program:  J.program) -> 
-      let external_module_ids = 
-        Lam_compile_env.get_required_modules  
-          may_required_modules  
-          (Js_fold_basic.calculate_hard_dependencies program.block)
-        |>
-        (fun x ->
-           if !Js_config.sort_imports then
-             Ext_list.sort_via_array x
-               (fun id1 id2 ->
-                  Ext_string.compare (Lam_module_ident.name id1) (Lam_module_ident.name id2)
-               ) 
-           else
-             x
-        )
+      let external_module_ids : Lam_module_ident.t list = 
+        if !Js_config.all_module_aliases then []
+        else 
+        let x = Lam_compile_env.get_required_modules  
+            may_required_modules  
+            (Js_fold_basic.calculate_hard_dependencies program.block) in 
+        if !Js_config.sort_imports then
+          Ext_list.sort_via_array x
+            (fun id1 id2 ->
+               Ext_string.compare (Lam_module_ident.name id1) (Lam_module_ident.name id2)
+            ) 
+        else
+          x
       in
       Warnings.check_fatal ();  
       let effect =