don't coerce slider currentvalue attrs when !visible

Author: rreusser

src/components/sliders/defaults.js

@@ -65,11 +65,18 @@ function sliderDefaults(sliderIn, sliderOut, layoutOut) {
     coerce('pad.b');
     coerce('pad.l');
 
-    coerce('currentvalue.visible');
-    coerce('currentvalue.xanchor');
-    coerce('currentvalue.prefix');
-    coerce('currentvalue.suffix');
-    coerce('currentvalue.offset');
+    Lib.coerceFont(coerce, 'font', layoutOut.font);
+
+    var currentValueIsVisible = coerce('currentvalue.visible');
+
+    if(currentValueIsVisible) {
+        coerce('currentvalue.xanchor');
+        coerce('currentvalue.prefix');
+        coerce('currentvalue.suffix');
+        coerce('currentvalue.offset');
+
+        Lib.coerceFont(coerce, 'currentvalue.font', sliderOut.font);
+    }
 
     coerce('transition.duration');
     coerce('transition.easing');
@@ -82,9 +89,6 @@ function sliderDefaults(sliderIn, sliderOut, layoutOut) {
     coerce('tickwidth');
     coerce('tickcolor');
     coerce('minorticklen');
-
-    Lib.coerceFont(coerce, 'font', layoutOut.font);
-    Lib.coerceFont(coerce, 'currentvalue.font', sliderOut.font);
 }
 
 function stepsDefaults(sliderIn, sliderOut) {

test/jasmine/tests/sliders_test.js

@@ -57,6 +57,23 @@ describe('sliders defaults', function() {
         expect(layoutOut.sliders[2].active).toBeUndefined();
     });
 
+    it('should not coerce currentvalue defaults unless currentvalue is visible', function() {
+        layoutIn.sliders = [{
+            currentvalue: {
+                visible: false,
+                xanchor: 'left'
+            },
+            steps: [
+                {method: 'restyle', args: [], label: 'step0'},
+                {method: 'restyle', args: [], label: 'step1'}
+            ]
+        }];
+
+        supply(layoutIn, layoutOut);
+
+        expect(layoutOut.sliders[0].currentvalue.xanchor).toBeUndefined();
+    });
+
     it('should set the default values equal to the labels', function() {
         layoutIn.sliders = [{
             steps: [{