add noHover trace module category,

use it to determine if we coerce `hoverinfo` and `hoverlabel`
in Plots.supplyTraceDefaults

Author: etpinard

src/plots/plots.js

@@ -1218,8 +1218,7 @@ plots.supplyTraceDefaults = function(traceIn, traceOut, colorIndex, layout, trac
                         if(subplots[attri]) Lib.pushUnique(subplots[attri], vali);
                         subplotId += vali;
                     }
-                }
-                else {
+                } else {
                     subplotId = Lib.coerce(traceIn, traceOut, subplotAttrs, subplotAttr);
                 }
 
@@ -1230,18 +1229,6 @@ plots.supplyTraceDefaults = function(traceIn, traceOut, colorIndex, layout, trac
         }
     }
 
-    function coerceUnlessPruned(attr, dflt, cb) {
-        if(_module && (attr in _module.attributes) && _module.attributes[attr] === undefined) {
-            // Pruned
-        } else {
-            if(cb && typeof cb === 'function') {
-                cb();
-            } else {
-                coerce(attr, dflt);
-            }
-        }
-    }
-
     if(visible) {
         coerce('customdata');
         coerce('ids');
@@ -1250,33 +1237,33 @@ plots.supplyTraceDefaults = function(traceIn, traceOut, colorIndex, layout, trac
             traceOut._dfltShowLegend = true;
             coerce('showlegend');
             coerce('legendgroup');
-        }
-        else {
+        } else {
             traceOut._dfltShowLegend = false;
         }
 
-        coerceUnlessPruned('hoverlabel', '', function() {
-            Registry.getComponentMethod(
-                'fx',
-                'supplyDefaults'
-            )(traceIn, traceOut, defaultColor, layout);
-        });
-
-        // TODO add per-base-plot-module trace defaults step
-
         if(_module) {
             _module.supplyDefaults(traceIn, traceOut, defaultColor, layout);
-            if(!traceOut.hovertemplate) Lib.coerceHoverinfo(traceIn, traceOut, layout);
         }
 
-        if(!Registry.traceIs(traceOut, 'noOpacity')) coerce('opacity');
+        if(!Registry.traceIs(traceOut, 'noOpacity')) {
+            coerce('opacity');
+        }
 
         if(Registry.traceIs(traceOut, 'notLegendIsolatable')) {
             // This clears out the legendonly state for traces like carpet that
             // cannot be isolated in the legend
             traceOut.visible = !!traceOut.visible;
         }
 
+        if(!Registry.traceIs(traceOut, 'noHover')) {
+            if(!traceOut.hovertemplate) Lib.coerceHoverinfo(traceIn, traceOut, layout);
+
+            // parcats support hover, but not hoverlabel stylings (yet)
+            if(traceOut.type !== 'parcats') {
+                Registry.getComponentMethod('fx', 'supplyDefaults')(traceIn, traceOut, defaultColor, layout);
+            }
+        }
+
         if(_module && _module.selectPoints) {
             coerce('selectedpoints');
         }

src/traces/parcoords/attributes.js

@@ -20,8 +20,6 @@ var templatedArray = require('../../plot_api/plot_template').templatedArray;
 module.exports = {
     domain: domainAttrs({name: 'parcoords', trace: true, editType: 'calc'}),
 
-    hoverlabel: undefined,
-
     labelfont: fontAttrs({
         editType: 'calc',
         description: 'Sets the font for the `dimension` labels.'

src/traces/parcoords/index.js

@@ -23,7 +23,7 @@ Parcoords.colorbar = {
 Parcoords.moduleType = 'trace';
 Parcoords.name = 'parcoords';
 Parcoords.basePlotModule = require('./base_plot');
-Parcoords.categories = ['gl', 'regl', 'noOpacity'];
+Parcoords.categories = ['gl', 'regl', 'noOpacity', 'noHover'];
 Parcoords.meta = {
     description: [
         'Parallel coordinates for multidimensional exploratory data analysis.',