Tweak formatting rules. Fix #211.

lib/src/chunk.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart_style.src.chunk;
 
 import 'debug.dart';
 
 /// Tracks where a selection start or end point may appear in some piece of
 /// text.
@@ skipping 212 matching lines @@
 /// most desirable.
 class Cost {
   /// The smallest cost.
   ///
   /// This isn't zero because we want to ensure all splitting has *some* cost,
   /// otherwise, the formatter won't try to keep things on one line at all.
   /// Almost all splits and spans use this. Greater costs tend to come from a
   /// greater number of nested spans.
   static const normal = 1;
 
-  /// The cost of splitting after a "=" both for assignment and initialization.
+  /// Splitting after a "=" both for assignment and initialization.
   static const assignment = 2;
 
+  /// Splitting before the first argument when it happens to be a function
+  /// expression with a block body.
+  static const firstBlockArgument = 2;
+
+  /// The series of positional arguments.
+  static const positionalArguments = 2;
+
+  /// Splitting inside the brackets of a list with only one element.
+  static const singleElementList = 2;
+
   /// The cost of a single character that goes past the page limit.
   ///
   /// This cost is high to ensure any solution that fits in the page is
   /// preferred over one that does not.
   static const overflowChar = 1000;
 }
 
 /// Controls whether or not one or more soft split [Chunk]s are split.
 ///
 /// When [LineSplitter] tries to split a line to fit within its page width, it
@@ skipping 14 matching lines @@
   final int cost;
 
   /// The other [SplitParam]s that are "implied" by this one.
   ///
   /// Implication means that if the splitter chooses to split this param, it
   /// must also split all of its implied ones (transitively). Implication is
   /// one-way. If A implies B, it's fine to split B without splitting A.
   final implies = <SplitParam>[];
 
   /// Creates a new [SplitParam].
-  SplitParam([this.cost = Cost.normal]);
+  SplitParam([int cost])
+      : cost = cost != null ? cost : Cost.normal;
 
   String toString() => "$id";
 
   int get hashCode => id.hashCode;
 
   bool operator ==(other) => identical(this, other);
 }
 
 /// Delimits a range of chunks that must end up on the same line to avoid an
 /// additional cost.
@@ skipping 71 matching lines @@
   /// Whether this comment starts at column one in the source.
   ///
   /// Comments that start at the start of the line will not be indented in the
   /// output. This way, commented out chunks of code do not get erroneously
   /// re-indented.
   final bool isStartOfLine;
 
   SourceComment(this.text, this.linesBefore,
       {this.isLineComment, this.isStartOfLine});
 }