40 columns                              |
>>> discard newlines before library


library a;
<<<
library a;
>>> discard newlines before first import


import 'a.dart';
<<<
import 'a.dart';
>>> discard newlines before first export


export 'a.dart';
<<<
export 'a.dart';
>>> discard newlines before first class


class A {}
<<<
class A {}
>>> discard newlines before first variable


var a = 1;
<<<
var a = 1;
>>> discard newlines before first function


foo() {}
<<<
foo() {}
>>> collapse extra newlines between declarations


class A {}


class B = Base with Mixin;


var c = 1;


d() {}


<<<
class A {}

class B = Base with Mixin;

var c = 1;

d() {}
>>> require at least a single newline between declarations
class A {} class B = Base with Mixin; var c = 1; d() {}
<<<
class A {}
class B = Base with Mixin;
var c = 1;
d() {}
>>> force two newlines between directives and declarations
library a; var b;
<<<
library a;

var b;
>>> dartbug.com/15912
abstract class A = B with C<E>;
<<<
abstract class A = B with C<E>;