Enforce dart_style's non-whitespace style fixes, i.e., dart format . --fix

[bradyt]

I have my *.g.dart files committed in git, and I have dart format . --fix running in CI. I would like it if the code generated by built_value followed the advice found in dart format's --fix rules.

> dart help format
...
    --fix                      Apply all style fixes.

• https://github.com/dart-lang/dart_style#style-fixes
• https://github.com/dart-lang/dart_style/blob/2.0.3/lib/src/style_fix.dart

To see what this looks like, try a fresh clone of built_value and try dart format . --fix there.

For example,

modified   example/lib/values.g.dart
@@ -6,16 +6,16 @@ part of values;
 // BuiltValueGenerator
 // **************************************************************************
 
-Serializer<SimpleValue> _$simpleValueSerializer = new _$SimpleValueSerializer();
+Serializer<SimpleValue> _$simpleValueSerializer = _$SimpleValueSerializer();

I didn't attempt to dig deep into the issue, I don't know if a related issue can be filed with source_gen, for example.

I'll try the following as a quick fix:

dart format $(find . \( -name '*.dart' ! -name '*.g.dart' \)) --fix

[davidmorgan]

I think this would be for source_gen to implement; the formatting isn't handled in built_value.

[bradyt]

Not suggesting any urgency here, just summarizing the relevant and recent decision at source_gen.

I still don't even know if this could be addressed at built_value.dart.

Are you opposed to doing even just the cascade fix? All the others are things that builder authors really could fix on their own I think.

dart-lang/source_gen#552 (comment)

So I think source_gen is only applying single-cascade-statements. For example, they are not applying optional-new.

Summary of options:

Fwiw this is the list of fixes:

  static const docComments = StyleFix._(
      'doc-comments', 'Use triple slash for documentation comments.');

  static const functionTypedefs = StyleFix._(
      'function-typedefs', 'Use new syntax for function type typedefs.');

  static const namedDefaultSeparator = StyleFix._('named-default-separator',
      'Use "=" as the separator before named parameter default values.');

  static const optionalConst = StyleFix._(
      'optional-const', 'Remove "const" keyword inside constant context.');

  static const optionalNew =
      StyleFix._('optional-new', 'Remove "new" keyword.');

  static const singleCascadeStatements = StyleFix._('single-cascade-statements',
      'Remove unnecessary single cascades from expression statements.');

-- dart-lang/source_gen#552 (comment).

[bradyt]

I've experimented with removing "new" from parts of the source code, and realized perhaps a better description of the issue is required. Rather than point at the entire project as being effected by dart format . --fix, I guess I should point at something dependent on the project, emphasizing the generating output, using example projects embedded here. For example:

> cd example
> dart format . --fix
> # note the diff representing the "fixed" output
> dart run build_runner build
> # note the "fixed" diff is removed