fix #4251 - add delay before transitionTraces()

... to remove "jump" caused by transitionTraces()

Author: etpinard

src/plots/plots.js

@@ -2611,14 +2611,14 @@ plots.transitionFromReact = function(gd, restyleFlags, relayoutFlags, oldFullLay
                 axisTransitionOpts = Lib.extendFlat({}, transitionOpts, {duration: 0});
                 transitionedTraces = allTraceIndices;
                 traceTransitionOpts = transitionOpts;
-                transitionTraces();
                 setTimeout(transitionAxes, transitionOpts.duration);
+                transitionTraces();
             } else {
                 axisTransitionOpts = transitionOpts;
                 transitionedTraces = null;
                 traceTransitionOpts = Lib.extendFlat({}, transitionOpts, {duration: 0});
+                setTimeout(transitionTraces, axisTransitionOpts.duration);
                 transitionAxes();
-                transitionTraces();
             }
         } else if(axEdits.length) {
             axisTransitionOpts = transitionOpts;

test/jasmine/tests/transition_test.js

@@ -694,10 +694,10 @@ describe('Plotly.react transitions:', function() {
             assertSpies('both trace and layout transitions', [
                 [Plots, 'transitionFromReact', 1],
                 [gd._fullLayout._basePlotModules[0], 'transitionAxes', 1],
-                // one instantaneous transition options to halt other trace transitions (if any)
-                [gd._fullLayout._basePlotModules[0], 'plot', [gd, null, {duration: 0, easing: 'cubic-in-out', ordering: 'layout first'}, 'function']],
                 [Axes, 'drawOne', 1],
                 [Axes, 'drawOne', 1],
+                // one instantaneous transition options to halt other trace transitions (if any)
+                [gd._fullLayout._basePlotModules[0], 'plot', [gd, null, {duration: 0, easing: 'cubic-in-out', ordering: 'layout first'}, 'function']],
                 [Axes, 'drawOne', 1],
                 [Axes, 'drawOne', 1],
                 // one _module.plot call from the relayout at end of axis transition