Roll Observatory deps (charted -> ^0.3.0)

packages/charted/lib/svg/shapes/line.dart

 //
 // Copyright 2014 Google Inc. All rights reserved.
 //
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file or at
 // https://developers.google.com/open-source/licenses/bsd
 //
 
 part of charted.svg.shapes;
 
 /// Function to convert a list of points to path.
 typedef String LineInterpolator(Iterable<math.Point> points, int tension);
 
 ///
 /// [SvgLine] provides a data-driven way to create path descriptions
 /// that can be used to draw lines.
 ///
 class SvgLine implements SvgShape {
   static const LINE_INTERPOLATOR_LINEAR = 'linear';
 
-  static final LINE_INTERPOLATORS = {
-    LINE_INTERPOLATOR_LINEAR: _linear
-  };
+  static final LINE_INTERPOLATORS = {LINE_INTERPOLATOR_LINEAR: _linear};
 
   /// Callback to access/convert datum to x coordinate value.
   final SelectionValueAccessor<num> xValueAccessor;
 
   /// Callback to access/convert datum to y coordinate value.
   final SelectionValueAccessor<num> yValueAccessor;
 
   /// Callback that is used to determine if a value is considered valid.
   /// If [isDefined] returns false at any time, the value isn't part
   /// of the line - the line would be split.
   final SelectionCallback<bool> isDefined;
 
   /// Interpolator that is used for creating the path.
   final LineInterpolator interpolator;
 
   /// Tension of the line, as used by a few interpolators.
   final int tension;
 
-  SvgLine({
-      this.xValueAccessor: defaultDataToX,
+  SvgLine(
+      {this.xValueAccessor: defaultDataToX,
       this.yValueAccessor: defaultDataToY,
       this.isDefined: defaultIsDefined,
       this.tension: 0,
-      String interpolate: LINE_INTERPOLATOR_LINEAR })
+      String interpolate: LINE_INTERPOLATOR_LINEAR})
       : interpolator = LINE_INTERPOLATORS[interpolate] {
     assert(interpolator != null);
   }
 
   /// Generates path for drawing a line based in the selected [interpolator]
   @override
   String path(data, int index, Element e) {
     assert(data is Iterable);
-    var segments = new StringBuffer(),
-        points = [];
+    var segments = new StringBuffer(), points = [];
     for (int i = 0, len = data.length; i < len; ++i) {
       final d = data.elementAt(i);
       if (isDefined(d, i, e)) {
         points.add(new math.Point(xValueAccessor(d, i), yValueAccessor(d, i)));
-      } else if (points.isNotEmpty){
+      } else if (points.isNotEmpty) {
         segments.write('M${interpolator(points, tension)}');
         points.clear();
       }
     }
     if (points.isNotEmpty) {
       segments.write('M${interpolator(points, tension)}');
     }
     return segments.toString();
   }
 
   /// Default implementation of [xValueAccessor].
   /// Returns the first element if [d] is an iterable, otherwise returns [d].
   static num defaultDataToX(d, i) => d is Iterable ? d.first : d;
 
   /// Default implementation of [yValueAccessor].
   /// Returns the second element if [d] is an iterable, otherwise returns [d].
   static num defaultDataToY(d, i) => d is Iterable ? d.elementAt(1) : d;
 
   /// Default implementation of [isDefined].
   /// Returns true for all non-null values of [d].
   static bool defaultIsDefined(d, i, e) => d != null;
 
   /// Linear interpolator.
   static String _linear(Iterable points, _) =>
       points.map((pt) => '${pt.x},${pt.y}').join('L');
 }