Fix js.py readFileSync, add isbrowser variable after init_python, etc

Author: rafi16jan

README.md

@@ -99,26 +99,30 @@ init_python(stack_size)
 NEW!! This function execute js.py to expose JS API to Python, even some helper function and experimental asynchronous queue/stack logic. Example:
 
 ```javascript
-import mp_js from 'micropython';
+mp_js = require('micropython');
 
 (async () => {
   await mp_js;
   await mp_js.init_python(64 * 1024);
   await mp_js.do_str(`
-  
+
   import js
-  
-  #This function executes every line one by one and await promise if it returns a promise
+
+  #This function executes every line but exit the event loop if wait function is called and resumes after it resolve
   exec("""
-  
-  require = JS('require')
-  fetch = require('node-fetch') #Or do JS('window.fetch') on browser
+
+  fetch = False
+  if isbrowser:
+     fetch = JS('fetch')
+  else:
+     require = JS('require')
+     fetch = require('node-fetch')
   response = fetch('https://github.com')
-  response = wait(response) #This is the 'await' equivalent
+  response = wait(response)
   result = response.text()
   result = wait(result)
-  print(result) #Print the resulting HTML
-  
+  print(result)
+
   """)
   `);
 })();

index.js

@@ -18,7 +18,7 @@ global.mpjsPrintStdout = stdout_print;
 const mp = require('./lib/micropython.js');
 if (typeof window === 'undefined' && typeof importScripts === 'undefined') {
   browser = false;
-  pyjs = require('fs').readFileSync('./js.py', {pwd: __dirname});
+  pyjs = require('fs').readFileSync(__dirname + '/js.py').toString();
 }
 else {
   pyjs = require('!raw-loader!./js.py');
@@ -44,6 +44,8 @@ if (browser) {
 
 global.AsyncFunction = (async () => {}).constructor;
 
+let python_browser;
+
 module.exports = (async () => {
   await wait_exist(() => global.mp_js_init);
   const methods = {}
@@ -53,10 +55,10 @@ module.exports = (async () => {
     const codes = code.split('\n');
     let spaces = '';
     for (let line of codes) {
-      if (!line) continue;
+      if (!line || !line.match(/[a-z]/i)) continue;
       let index = 0;
       for (let word of line) {
-        if (index === 0 && word !== ' ') break;
+        if (index === 0 && word.match(/[a-z]/i)) break;
         if (word === ' ') spaces += ' ';
         index += 1;
       }
@@ -72,16 +74,26 @@ module.exports = (async () => {
       }
       if (concurrent) {
         const result = [];
+        let code_cache = [];
         for (var each of new_code) {
           let await_code;
           if (each.indexOf(' = wait(') > -1) {
+            if (code_cache.length > 0) {
+              result.push(await global.mp_js_do_str(code_cache.join('\n'), false));
+              code_cache = [];
+            }
             const [variable, wait] = each.split(' = ')
             const promise = wait.slice(5, -1);
             await_code = variable + ' = ' + promise + '._value';
           }
+          else {
+            code_cache.push(each);
+            continue;
+          }
           result.push(await global.mp_js_do_str(each, false));
           if (await_code) await global.mp_js_do_str(await_code, false);
         }
+        if (code_cache.length > 0) result.push(await global.mp_js_do_str(code_cache.join('\n'), false));
         return result.join('\n');
       }
       code = new_code.join('\n');
@@ -96,6 +108,13 @@ module.exports = (async () => {
   }
   methods.init_python = async (stack) => {
     methods.init(stack);
+    if (!python_browser) {
+      await methods.do_str(`
+        import json
+        isbrowser = json.loads('${browser}')
+      `);
+      python_browser = true;
+    }
     return await methods.do_str(pyjs);
   }
   global.mp_js_do_str = methods.do_str;

js.py

@@ -85,7 +85,7 @@ def __getattr__(self, key):
         name = self._name + '.' + key
         js_exec("""
           let object = {0};
-          if (object.constructor === Promise) {
+          if (object && object.constructor === Promise) {
             await global.mp_js_do_str(`
               import js
               objcache['{0}'] = JSPromise('{0}')
@@ -97,7 +97,7 @@ def __getattr__(self, key):
             if (object && object.constructor === Object) for (let key in Object.keys(object)) {
               if (object.indexOf(key) < 0) throw Error('Not a JSON');
             }
-            else if (object && object.constructor === Function || (object && object.constructor && object.constructor.name === 'AsyncFunction')) {
+            else if (object && (object.constructor === Function || object.constructor === AsyncFunction)) {
               delete global.mpjscache['{0}'];
               return global.mp_js_do_str(`
                 import js
@@ -141,7 +141,7 @@ def function(*args):
           }
           //object = object(...{1});
           global.mpjscache['{0}'] = object;
-          if (object.constructor === Promise) {
+          if (object && object.constructor === Promise) {
             await global.mp_js_do_str(`
               import js
               funcache['{0}'] = JSPromise('{0}')
@@ -154,7 +154,7 @@ def function(*args):
             if (object && object.constructor === Object) for (let key in Object.keys(object)) {
               if (object.indexOf(key) < 0) throw Error('Not a JSON');
             }
-            else if (object.constructor === Function || (object.constructor && object.constructor.name === 'AsyncFunction')) {
+            else if (object && (object.constructor === Function || object.constructor === AsyncFunction)) {
               return global.mp_js_do_str(`
                 import js
                 resolve(funcache, '{0}', JSFunction('{0}'))
@@ -180,7 +180,7 @@ def function(*args):
 def JS(variable):
     js_exec("""
       let object = {0};
-      if (object.constructor === Promise) {
+      if (object && object.constructor === Promise) {
         await global.mp_js_do_str(`
           import js
           objcache['{0}'] = JSPromise('{0}')