fixes #1600 - allow z cartesian traces to have a name hover label

Author: etpinard

src/components/fx/hover.js

@@ -696,7 +696,7 @@ function createHoverText(hoverData, opts) {
         // to get custom 'name' labels pass cleanPoint
         if(d.nameOverride !== undefined) d.name = d.nameOverride;
 
-        if(d.name && d.zLabelVal === undefined) {
+        if(d.name) {
             // strip out our pseudo-html elements from d.name (if it exists at all)
             name = svgTextUtils.plainText(d.name || '');
 

test/jasmine/tests/hover_label_test.js

@@ -444,7 +444,53 @@ describe('hover info', function() {
 
                 done();
             });
+        });
+    });
+
+    describe('\'hover info for x/y/z traces', function() {
+        function _hover(gd, xpx, ypx) {
+            Fx.hover(gd, { xpx: xpx, ypx: ypx }, 'xy');
+            delete gd._lastHoverTime;
+        }
+
+        function _assert(nameLabel, lines) {
+            expect(d3.select('g.axistext').size()).toEqual(0, 'no common label');
+
+            var sel = d3.select('g.hovertext');
+            expect(sel.select('text.name').html()).toEqual(nameLabel, 'name label');
+            sel.select('text.nums').selectAll('tspan').each(function(_, i) {
+                expect(d3.select(this).html()).toEqual(lines[i], 'lines ' + i);
+            });
+        }
 
+        it('should display correct label content', function(done) {
+            var gd = createGraphDiv();
+
+            Plotly.plot(gd, [{
+                type: 'heatmap',
+                y: [0, 1],
+                z: [[1, 2, 3], [2, 2, 1]],
+                name: 'one',
+            }, {
+                type: 'heatmap',
+                y: [2, 3],
+                z: [[1, 2, 3], [2, 2, 1]],
+                name: 'two'
+            }], {
+                width: 500,
+                height: 400,
+                margin: {l: 0, t: 0, r: 0, b: 0}
+            })
+            .then(function() {
+                _hover(gd, 250, 100);
+                _assert('two', ['x: 1', 'y: 3', 'z: 2']);
+            })
+            .then(function() {
+                _hover(gd, 250, 300);
+                _assert('one', ['x: 1', 'y: 1', 'z: 2']);
+            })
+            .catch(fail)
+            .then(done);
         });
     });