file_names

Name source files using lowercase_with_underscores.

DO name source files using lowercase_with_underscores.

Some file systems are not case-sensitive, so many projects require filenames to be all lowercase. Using a separating character allows names to still be readable in that form. Using underscores as the separator ensures that the name is still a valid Dart identifier, which may be helpful if the language later supports symbolic imports.

BAD:

• SliderMenu.dart
• filesystem.dart
• file-system.dart

GOOD:

• slider_menu.dart
• file_system.dart

Files without a strict .dart extension are ignored. For example:

OK:

• file-system.g.dart
• SliderMenu.css.dart

The lint library_names can be used to enforce the same kind of naming on the library.

To enable the file_names rule, add file_names under linter > rules in your analysis_options.yaml file:

linter:
  rules:
    - file_names

If you're instead using the YAML map syntax to configure linter rules, add file_names: true under linter > rules:

linter:
  rules:
    file_names: true