Fix react category order of matching axes

src/lib/relink_private.js

@@ -24,9 +24,9 @@ module.exports = function relinkPrivateKeys(toContainer, fromContainer) {
         var fromVal = fromContainer[k];
         var toVal = toContainer[k];
 
-        if(toVal === fromVal) {
-            continue;
-        }
+        if(toVal === fromVal) continue;
+        if(k !== '_categories' && toContainer.matches) continue;
+
         if(k.charAt(0) === '_' || typeof fromVal === 'function') {
             // if it already exists at this point, it's something
             // that we recreate each time around, so ignore it

test/jasmine/tests/axes_test.js

@@ -5431,3 +5431,77 @@ describe('Test template:', function() {
         .then(done);
     });
 });
+
+describe('more react tests', function() {
+    var gd;
+
+    beforeEach(function() {
+        gd = createGraphDiv();
+    });
+
+    afterEach(destroyGraphDiv);
+
+    it('should sort catgories on matching axes using react', function(done) {
+        var fig = {
+            data: [{
+                yaxis: 'y',
+                xaxis: 'x',
+                y: [0, 0],
+                x: ['A', 'Z']
+            }, {
+                yaxis: 'y2',
+                xaxis: 'x2',
+                y: [0, 0],
+                x: ['A', 'Z']
+            }],
+            layout: {
+                width: 400,
+                height: 300,
+                showlegend: false,
+                xaxis: {
+                    matches: 'x2',
+                    domain: [ 0, 1]
+                },
+                yaxis: {
+                    domain: [0.6, 1],
+                    anchor: 'x'
+                },
+                xaxis2: {
+                    domain: [0, 1],
+                    anchor: 'y2'
+                },
+                yaxis2: {
+                    domain: [0, 0.4],
+                    anchor: 'x2'
+                }
+            }
+        };
+
+        Plotly.newPlot(gd, fig)
+        .then(function() {
+            expect(gd._fullLayout.xaxis._categories).toEqual(['A', 'Z']);
+            expect(gd._fullLayout.xaxis2._categories).toEqual(['A', 'Z']);
+            expect(gd._fullLayout.xaxis._categoriesMap).toEqual({A: 0, Z: 1});
+            expect(gd._fullLayout.xaxis2._categoriesMap).toEqual({A: 0, Z: 1});
+        })
+        .then(function() {
+            var newFig = JSON.parse(JSON.stringify(fig));
+
+            // flip order
+            newFig.data[0].x.reverse();
+            newFig.data[0].y.reverse();
+            newFig.data[1].x.reverse();
+            newFig.data[1].y.reverse();
+
+            return Plotly.react(gd, newFig);
+        })
+        .then(function() {
+            expect(gd._fullLayout.xaxis._categories).toEqual(['Z', 'A']);
+            expect(gd._fullLayout.xaxis2._categories).toEqual(['Z', 'A']);
+            expect(gd._fullLayout.xaxis._categoriesMap).toEqual({Z: 0, A: 1});
+            expect(gd._fullLayout.xaxis2._categoriesMap).toEqual({Z: 0, A: 1});
+        })
+        .catch(failTest)
+        .then(done);
+    });
+});