dart2js thinks two numbers with the same value are not equal

[sethladd]

Here is the sample code:

import('dart:html');

// compile me to JavaScript with dart2js
void main() {
  getCurrentPlatform() {
    int n=9007199254740992;
    int newInt = n + 1;
    if (newInt == n) {
      print('when compiled to JavaScript, I should return js');
      return 'js';
    } else {
      print('however, when compiled with dart2js, I return here');
      return 'vm';
    }
  }
  
  getCurrentPlatform();
}

Dart2js thinks newInt != n when compiling this to JavaScript. Which is odd because if you print out newInt and n, both numbers have the same value.

I have attached the resulting compiled output.

---

Attachment:
detectweborvm.dart.js (89.67 KB)

[sethladd]

Changed the title to: "dart2js thinks two numbers with the same value are not equal".

[rakudrama]

Set owner to @floitschG.
Added Duplicate label.
Marked as being merged into #2887.