From 93f5f802165c3b8ab01a0393409cbd1c352596c8 Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Sun, 28 Apr 2019 22:16:27 +1000
Subject: [PATCH] javascript: Pass (error) exit value out from script to
 process caller.

---
 ports/javascript/main.c     | 19 +++++++++++++++----
 ports/javascript/wrapper.js |  6 +++---
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/ports/javascript/main.c b/ports/javascript/main.c
index 65bae98b44..f8ef0e7c55 100644
--- a/ports/javascript/main.c
+++ b/ports/javascript/main.c
@@ -39,7 +39,8 @@
 #include "library.h"
 
 #if MICROPY_ENABLE_COMPILER
-void do_str(const char *src, mp_parse_input_kind_t input_kind) {
+int do_str(const char *src, mp_parse_input_kind_t input_kind) {
+    int ret = 0;
     nlr_buf_t nlr;
     if (nlr_push(&nlr) == 0) {
         mp_lexer_t *lex = mp_lexer_new_from_str_len(MP_QSTR__lt_stdin_gt_, src, strlen(src), 0);
@@ -51,18 +52,28 @@ void do_str(const char *src, mp_parse_input_kind_t input_kind) {
     } else {
         // uncaught exception
         if (mp_obj_is_subclass_fast(mp_obj_get_type((mp_obj_t)nlr.ret_val), &mp_type_SystemExit)) {
-            // at the moment, the value of SystemExit is unused
+            mp_obj_t exit_val = mp_obj_exception_get_value(MP_OBJ_FROM_PTR(nlr.ret_val));
+            if (exit_val != mp_const_none) {
+                mp_int_t int_val;
+                if (mp_obj_get_int_maybe(exit_val, &int_val)) {
+                    ret = int_val & 255;
+                } else {
+                    ret = 1;
+                }
+            }
         } else {
             mp_obj_print_exception(&mp_plat_print, (mp_obj_t)nlr.ret_val);
+            ret = 1;
         }
     }
+    return ret;
 }
 #endif
 
 static char *stack_top;
 
-void mp_js_do_str(const char *code) {
-    do_str(code, MP_PARSE_FILE_INPUT);
+int mp_js_do_str(const char *code) {
+    return do_str(code, MP_PARSE_FILE_INPUT);
 }
 
 int mp_js_process_char(int c) {
diff --git a/ports/javascript/wrapper.js b/ports/javascript/wrapper.js
index 84ad2ae3a7..ae0f24e7e4 100644
--- a/ports/javascript/wrapper.js
+++ b/ports/javascript/wrapper.js
@@ -29,7 +29,7 @@ var Module = {};
 var mainProgram = function()
 {
   mp_js_init = Module.cwrap('mp_js_init', 'null', ['number']);
-  mp_js_do_str = Module.cwrap('mp_js_do_str', 'null', ['string']);
+  mp_js_do_str = Module.cwrap('mp_js_do_str', 'number', ['string']);
   mp_js_init_repl = Module.cwrap('mp_js_init_repl', 'null', ['null']);
   mp_js_process_char = Module.cwrap('mp_js_process_char', 'number', ['number']);
 
@@ -69,9 +69,9 @@ var mainProgram = function()
               }
           });
       } else {
-          mp_js_do_str(contents);
+          process.exitCode = mp_js_do_str(contents);
       }
   }
 }
 
-Module["onRuntimeInitialized"] = mainProgram;
\ No newline at end of file
+Module["onRuntimeInitialized"] = mainProgram;