Start building up the spec coverage. Fix hover label bug (yay, specs!)

lib/morris.line.coffee

@@ -192,7 +192,7 @@ class Morris.Line extends Morris.Grid
     @hoverSet.push(@hover)
     @hoverSet.push(@xLabel)
     @yLabels = []
-    for i in [0...@data.length]
+    for i in [0...@options.ykeys.length]
       yLabel = @r.text(0, @options.hoverFontSize * 1.5 * (i + 1.5) - @hoverHeight / 2, '')
         .attr('fill', @colorForSeries(i))
         .attr('font-size', @options.hoverFontSize)

morris.js

@@ -812,7 +812,7 @@
       this.hoverSet.push(this.xLabel);
       this.yLabels = [];
       _results = [];
-      for (i = _i = 0, _ref = this.data.length; 0 <= _ref ? _i < _ref : _i > _ref; i = 0 <= _ref ? ++_i : --_i) {
+      for (i = _i = 0, _ref = this.options.ykeys.length; 0 <= _ref ? _i < _ref : _i > _ref; i = 0 <= _ref ? ++_i : --_i) {
         yLabel = this.r.text(0, this.options.hoverFontSize * 1.5 * (i + 1.5) - this.hoverHeight / 2, '').attr('fill', this.colorForSeries(i)).attr('font-size', this.options.hoverFontSize);
         this.yLabels.push(yLabel);
         _results.push(this.hoverSet.push(yLabel));

spec/lib/line/set_data_spec.coffee

@@ -0,0 +1,67 @@
+describe 'Morris.Line data', ->
+
+  it 'should not alter user-supplied data', ->
+    my_data = [{x: 1, y: 1}, {x: 2, y: 2}]
+    expected_data = [{x: 1, y: 1}, {x: 2, y: 2}]
+    Morris.Line
+      element: 'graph'
+      data: my_data
+      xkey: 'x'
+      ykeys: ['y']
+      labels: ['dontcare']
+    my_data.should.deep.equal expected_data
+
+  describe 'ymin/ymax', ->
+
+    it 'should use a user-specified minimum and maximum value', ->
+      line = Morris.Line
+        element: 'graph'
+        data: [{x: 1, y: 1}]
+        xkey: 'x'
+        ykeys: ['y', 'z']
+        labels: ['y', 'z']
+        ymin: 10
+        ymax: 20
+      line.ymin.should.equal 10
+      line.ymax.should.equal 20
+
+    describe 'auto', ->
+
+      it 'should automatically calculate the minimum and maximum value', ->
+        line = Morris.Line
+          element: 'graph'
+          data: [{x: 1, y: 10}, {x: 2, y: 15}, {x: 3, y: null}, {x: 4}]
+          xkey: 'x'
+          ykeys: ['y', 'z']
+          labels: ['y', 'z']
+          ymin: 'auto'
+          ymax: 'auto'
+        line.ymin.should.equal 10
+        line.ymax.should.equal 15
+
+    describe 'auto [n]', ->
+
+      it 'should automatically calculate the minimum and maximum value', ->
+        line = Morris.Line
+          element: 'graph'
+          data: [{x: 1, y: 10}, {x: 2, y: 15}, {x: 3, y: null}, {x: 4}]
+          xkey: 'x'
+          ykeys: ['y', 'z']
+          labels: ['y', 'z']
+          ymin: 'auto 12'
+          ymax: 'auto 12'
+        line.ymin.should.equal 10
+        line.ymax.should.equal 15
+
+      it 'should use a user-specified minimum and maximum value', ->
+        line = Morris.Line
+          element: 'graph'
+          data: [{x: 1, y: 10}, {x: 2, y: 15}, {x: 3, y: null}, {x: 4}]
+          xkey: 'x'
+          ykeys: ['y', 'z']
+          labels: ['y', 'z']
+          ymin: 'auto 5'
+          ymax: 'auto 20'
+        line.ymin.should.equal 5
+        line.ymax.should.equal 20
+

spec/lib/line_spec.coffee

@@ -1,16 +1,5 @@
 describe 'Morris.Line', ->
 
-  it 'should not alter user-supplied data', ->
-    my_data = [{x: 1, y: 1}, {x: 2, y: 2}]
-    expected_data = [{x: 1, y: 1}, {x: 2, y: 2}]
-    Morris.Line
-      element: 'graph'
-      data: my_data
-      xkey: 'x'
-      ykeys: ['y']
-      labels: ['dontcare']
-    my_data.should.deep.equal expected_data
-
   it 'should raise an error when the placeholder element is not found', ->
     my_data = [{x: 1, y: 1}, {x: 2, y: 2}]
     fn = ->