avoid_border_all

v0.4.0 Warning Fix Widget Replacement

Flags usages of Border.all() which should be replaced with Border.fromBorderSide(BorderSide(...)). The Border.all() factory delegates to Border.fromBorderSide() internally, but it cannot be made const because it is a factory constructor.

Why use this rule

Border.all() calls Border.fromBorderSide() under the hood, so using Border.fromBorderSide(BorderSide(...)) directly allows the entire expression to be const. Const objects are canonicalized at compile time, which reduces allocations and improves performance — especially in build methods that run frequently.

See also: Border | Dart lint: prefer_const_constructors

Don’t

// Border.all() cannot be const
final border1 = Border.all();

// Border.all() with arguments
final border2 = Border.all(
  color: const Color(0xFF3355AA),
  width: 2.5,
  style: BorderStyle.solid,
);

Do

// Border.fromBorderSide() supports const
final border1 = const Border.fromBorderSide(BorderSide());

final border2 = const Border.fromBorderSide(
  BorderSide(color: Color(0xFF3355AA), width: 2.5, style: BorderStyle.solid),
);

Configuration

This rule is in the opinionated preset, so it is on with preset: opinionated, or by name:

many_lints.yaml

rules:
  avoid_border_all: true

To turn it off again:

many_lints.yaml

rules:
  avoid_border_all: false

To keep the rule on but skip certain paths, use per-rule exclude.

Related rules

• prefer_const_border_radius — Use BorderRadius.all(Radius.circular()) for const support.
• avoid_expanded_as_spacer — Use Spacer instead of Expanded with an empty child.
• avoid_incorrect_image_opacity — Use Image’s opacity parameter instead of wrapping in Opacity.
• avoid_wrapping_in_padding — Avoid wrapping widgets that support padding in a Padding widget.