Compiler: revisit static env handling

CHANGES.md

@@ -17,6 +17,7 @@
 * Compiler: introduce a Targetint module
   that follows the semantic of the backend (js or wasm)
 * Compiler: warn on joo_global_object
+* Compiler: revisit static env handling (#1708)
 * Runtime: change Sys.os_type on windows (Cygwin -> Win32)
 * Runtime: backtraces are really expensive, they need to be be explicitly
   requested at compile time (--enable with-js-error) or at startup (OCAMLRUNPARAM=b=1)

compiler/tests-env/dune

@@ -0,0 +1,27 @@
+(executable
+ (modes js)
+ (js_of_ocaml
+  (flags :standard --setenv JSOO_C=from-jsoo-args))
+ (name test))
+
+(rule
+ (target test.js)
+ (action
+  (with-outputs-to
+   %{target}
+   (cat %{dep:setup.js} %{dep:./test.bc.js}))))
+
+(rule
+ (target test.output)
+ (action
+  (with-outputs-to
+   %{target}
+   (setenv
+    JSOO_B
+    from-env
+    (run node %{dep:./test.js})))))
+
+(rule
+ (alias runtest)
+ (action
+  (diff test.reference test.output)))

compiler/tests-env/setup.js

@@ -0,0 +1,2 @@
+globalThis.jsoo_env = {};
+globalThis.jsoo_env["JSOO_A"] = "from-global-this";

compiler/tests-env/test.ml

@@ -0,0 +1,10 @@
+let test x =
+  match Sys.getenv x with
+  | exception Not_found -> print_endline (x ^ " not found")
+  | v -> print_endline (x ^ " = " ^ v)
+
+let () =
+  test "JSOO_A";
+  test "JSOO_B";
+  test "JSOO_C";
+  test "JSOO_D"

compiler/tests-env/test.reference

@@ -0,0 +1,4 @@
+JSOO_A = from-global-this
+JSOO_B = from-env
+JSOO_C = from-jsoo-args
+JSOO_D not found

runtime/sys.js

@@ -98,21 +98,27 @@ function caml_fatal_uncaught_exception(err) {
   }
 }
 
+//Provides: jsoo_static_env
+var jsoo_static_env = {};
+
 //Provides: caml_set_static_env
+//Requires: jsoo_static_env
 function caml_set_static_env(k, v) {
-  if (!globalThis.jsoo_static_env) globalThis.jsoo_static_env = {};
-  globalThis.jsoo_static_env[k] = v;
+  jsoo_static_env[k] = v;
   return 0;
 }
 
 //Provides: jsoo_sys_getenv (const)
+//Requires: jsoo_static_env
 function jsoo_sys_getenv(n) {
+  if (jsoo_static_env[n]) return jsoo_static_env[n];
   var process = globalThis.process;
   //nodejs env
   if (process && process.env && process.env[n] !== undefined)
     return process.env[n];
-  if (globalThis.jsoo_static_env && globalThis.jsoo_static_env[n])
-    return globalThis.jsoo_static_env[n];
+  if (globalThis.jsoo_env && typeof globalThis.jsoo_env[n] === "string") {
+    return globalThis.jsoo_env[n];
+  }
 }
 
 //Provides: caml_sys_getenv (const)