store and reuse hovermode get result

Author: archmoj

src/plot_api/plot_api.js

@@ -1739,13 +1739,14 @@ function _restyle(gd, aobj, traces) {
         // swap hovermode if set to "compare x/y data"
         if(ai === 'orientationaxes') {
             var hovermode = nestedProperty(gd.layout, 'hovermode');
-            if(hovermode.get() === 'x') {
+            var h = hovermode.get();
+            if(h === 'x') {
                 hovermode.set('y');
-            } else if(hovermode.get() === 'y') {
+            } else if(h === 'y') {
                 hovermode.set('x');
-            } else if(hovermode.get() === 'x unified') {
+            } else if(h === 'x unified') {
                 hovermode.set('y unified');
-            } else if(hovermode.get() === 'y unified') {
+            } else if(h === 'y unified') {
                 hovermode.set('x unified');
             }
         }