falcon

Rules / Style / avoid-single-cascade-in-expression-statements

avoid-single-cascade-in-expression-statements

lint/style/avoid-single-cascade-in-expression-statements
recommended
Same as avoid_single_cascade_in_expression_statements · Dart lints

Flags an expression statement that is a cascade with a single section.

A cascade (..) exists to chain several operations on one receiver; with a single section it buys nothing over an ordinary member access and only obscures intent. Rewrite foo..bar() as foo.bar(). Cascades with two or more sections are the idiomatic form and are not flagged.

Invalid

example.dartdart
void f1(StringBuffer a) {
  a..write('x');
}

void f2(List<int> list) {
  list..add(1);
}

void f3(Foo b) {
  b..field = 1;
}

void f4(List<int> c) {
  c..[0] = 2;
}

void f5(Foo d) {
  d..method();
}

void f6(StringBuffer e) {
  e..clear();
}
Single cascade in an expression statement — use `.` instead of `..`
1void f1(StringBuffer a) {
2 a..write('x');
Single cascade in an expression statement — use `.` instead of `..`
5void f2(List<int> list) {
6 list..add(1);
Single cascade in an expression statement — use `.` instead of `..`
9void f3(Foo b) {
10 b..field = 1;
Single cascade in an expression statement — use `.` instead of `..`
13void f4(List<int> c) {
14 c..[0] = 2;
Single cascade in an expression statement — use `.` instead of `..`
17void f5(Foo d) {
18 d..method();
Single cascade in an expression statement — use `.` instead of `..`
21void f6(StringBuffer e) {
22 e..clear();

Valid

example.dartdart
void g1(StringBuffer a) {
  a
    ..write('x')
    ..write('y');
}

void g2(List<int> list) {
  list.add(1);
}

void g3(Foo b) {
  final x = b..field = 1;
  print(x);
}

Foo g4(Foo d) {
  return d..method();
}

void g5(StringBuffer e) {
  e
    ..clear()
    ..write('z');
}

void g6(Foo f) {
  f.method();
}

How to configure

Set the severity of avoid-single-cascade-in-expression-statements in your falcon.json:

falcon.jsonjson
{
  "linter": {
    "rules": {
      "style": {
        "avoid-single-cascade-in-expression-statements": "error"
      }
    }
  }
}

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