40 columns                              |
>>> Single cascade on same line.
"foo"..toString();
<<<
"foo"..toString();
>>> Split multiple cascades even if they fit.
foo..fooBar()..toString();
<<<
foo
  ..fooBar()
  ..toString();
>>> Split long single cascade but not after target.
"foo"..toString(argument, argument, argument);
<<<
"foo"..toString(
  argument,
  argument,
  argument,
);
>>> Split at target if single cascade doesn't fit.
"some much longer string"..someLongMethod(argument, argument);
<<<
"some much longer string"
  ..someLongMethod(argument, argument);
>>> Split at target if single cascade doesn't fit.
"some much longer string"..someLongMethod(argument, argument, argument);
<<<
"some much longer string"
  ..someLongMethod(
    argument,
    argument,
    argument,
  );
>>> Split multiple cascades even if the same name.
list
  ..add("baz")
  ..add("bar");
<<<
list
  ..add("baz")
  ..add("bar");
>>> Setters.
foo..baz = 3..baz=5;
<<<
foo
  ..baz = 3
  ..baz = 5;
>>> Don't indent contained block arguments if cascade doesn't split.
"foo"..toString(() {body;});
<<<
"foo"..toString(() {
  body;
});
>>> Indent contained block arguments if cascade splits.
"foo"..another()..toString(() {body;});
<<<
"foo"
  ..another()
  ..toString(() {
    body;
  });
>>> Split if receiver precedence isn't obvious.
main() async {
  // These are OK.
  a = b..c();
  a += b..c();
  a.b..c();

  // These are unclear.
  a ? b : c..d();
  a ?? b..c();
  a && b..c();
  a || b..c();
  a == b..c();
  a <= b..c();
  a + b..c();
  a / b..c();
  a ^ b..c();
  a << b..c();
  -a..b();
  !a..b();
  --a..b();
  await a..b();
}
<<<
main() async {
  // These are OK.
  a = b..c();
  a += b..c();
  a.b..c();

  // These are unclear.
  a ? b : c
    ..d();
  a ?? b
    ..c();
  a && b
    ..c();
  a || b
    ..c();
  a == b
    ..c();
  a <= b
    ..c();
  a + b
    ..c();
  a / b
    ..c();
  a ^ b
    ..c();
  a << b
    ..c();
  -a
    ..b();
  !a
    ..b();
  --a
    ..b();
  await a
    ..b();
}
>>> Omit split if single section on list literal.
[veryLongElement,veryLongElement,veryLongElement,]..addAll(more);
<<<
[
  veryLongElement,
  veryLongElement,
  veryLongElement,
]..addAll(more);
>>> Omit split if single section on map literal.
var map = {1: veryLongElement,2: veryLongElement,3: veryLongElement,}..addAll(more);
<<<
var map = {
  1: veryLongElement,
  2: veryLongElement,
  3: veryLongElement,
}..addAll(more);
>>> Omit split if single section on record literal.
(veryLongElement,veryLongElement,veryLongElement,)..addAll(more);
<<<
(
  veryLongElement,
  veryLongElement,
  veryLongElement,
)..addAll(more);
>>> Omit split if single section on function call.
foo(veryLongElement,veryLongElement,veryLongElement)..addAll(more);
<<<
foo(
  veryLongElement,
  veryLongElement,
  veryLongElement,
)..addAll(more);
>>> Omit split if single section on instance creation.
new Foo(veryLongElement,veryLongElement,veryLongElement,)..addAll(more);
<<<
new Foo(
  veryLongElement,
  veryLongElement,
  veryLongElement,
)..addAll(more);
>>> Omit split if single section on expression call.
(foo)(veryLongElement,veryLongElement,veryLongElement,)..addAll(more);
<<<
(foo)(
  veryLongElement,
  veryLongElement,
  veryLongElement,
)..addAll(more);
>>> Prefer splitting inside collection instead of at cascade.
[element1, element2, element3]
  ..cascade();
<<<
[
  element1,
  element2,
  element3,
]..cascade();
>>> Don't force cascade to split on collection target if arg splits.
[1, 2, 3, 4]..cascade(() {;});
<<<
[1, 2, 3, 4]..cascade(() {
  ;
});
>>> Don't force cascade to split on collection target if target and arg split.
[veryLongElement,veryLongElement,veryLongElement,]..cascade(() {;});
<<<
[
  veryLongElement,
  veryLongElement,
  veryLongElement,
]..cascade(() {
  ;
});
>>> Null-aware getter.
foo?..baz..baz;
<<<
foo
  ?..baz
  ..baz;
>>> Null-aware setter.
foo?..baz = 3..baz=5;
<<<
foo
  ?..baz = 3
  ..baz = 5;
>>> Mixed null aware and regular cascades.
foo?..a()..b()..c();
<<<
foo
  ?..a()
  ..b()
  ..c();
>>> Cascade index.
object..[index]..method()..[index]=value;
<<<
object
  ..[index]
  ..method()
  ..[index] = value;
>>> Null-aware cascade index.
object?..[index]..method()..[index]=value;
<<<
object
  ?..[index]
  ..method()
  ..[index] = value;
>>> Property chain in cascade.
object..first.second.third
    ..fourth.fifth.sixth;
<<<
object
  ..first.second.third
  ..fourth.fifth.sixth;
>>> Split property chain in cascade.
object..firstProperty.secondProperty.thirdProperty
    ..fourthProperty.fifthProperty.sixthProperty;
<<<
object
  ..firstProperty
    .secondProperty
    .thirdProperty
  ..fourthProperty
    .fifthProperty
    .sixthProperty;
>>> Cascade chained property access setter.
object..a.b = value;
<<<
object..a.b = value;