dart run prints errors twice

[julemand101]

(Not entirely sure if this is actually an issue in pub or Dart SDK. Please just move the issue if it is posted wrongly) :)

Environment

Tested with the following:

Dart SDK version: 3.6.0-198.0.dev (dev) (Thu Aug 29 13:03:18 2024 -0700) on "windows_x64"
Dart SDK version: 3.5.2 (stable) (Wed Aug 28 10:01:20 2024 +0000) on "windows_x64"

Problem

When making a project containing a syntax error like:

void main() {
  print('')
}

And run it with dart run, we see the error message being printed twice:

$ dart run
Building package executable...
Failed to build advent_of_code_2022:advent_of_code_2022:
bin/advent_of_code_2022.dart:2:11: Error: Expected ';' after this.
  print('')
          ^
Failed to build advent_of_code_2022:advent_of_code_2022:
bin/advent_of_code_2022.dart:2:11: Error: Expected ';' after this.
  print('')
          ^

Expected behavior

Expected the error only be printed once like it is also the case if you run the program with:

$ dart run bin/advent_of_code_2022.dart
bin/advent_of_code_2022.dart:2:11: Error: Expected ';' after this.
  print('')
          ^

And:

$ dart bin/advent_of_code_2022.dart
bin/advent_of_code_2022.dart:2:11: Error: Expected ';' after this.
  print('')
          ^

Bonus observation

It looks like colors of the error message are missing in the output from dart run compared to dart run file.dart and dart file.dart:

Same behavior have also been noticed in both PowerShell and Bash for Windows.

[sigurdm]

I was not able to reproduce this on windows with latest flutter sdk.

PS C:\Users\sigurdm\blah> C:\Users\sigurdm\flutter\bin\flutter.bat --version
[...]
Flutter 3.25.0-1.0.pre.320 • channel master • https://github.com/flutter/flutter.git
Framework • revision d6e2b6aedb (6 hours ago) • 2024-09-10 01:27:20 -0400
Engine • revision 3dc8b71f96
Tools • Dart 3.6.0 (build 3.6.0-232.0.dev) • DevTools 2.39.0

PS C:\Users\sigurdm\blah> C:\Users\sigurdm\flutter\bin\cache\dart-sdk\bin\dart.exe run .\bin\syntax_error.dart
bin/syntax_error.dart:2:22: Error: Expected ';' after this.
  print('hello world')
                     ^
PS C:\Users\sigurdm\blah>

[sigurdm]

Oh - now I managed!

This is dart run :syntax_error not dart run bin/syntax_error.dart.