Add zoom tests

Author: n-riesco

test/jasmine/tests/zoom_test.js

@@ -0,0 +1,51 @@
+var d3 = require('d3');
+
+var Plotly = require('@lib/index');
+var Lib = require('@src/lib');
+
+var createGraphDiv = require('../assets/create_graph_div');
+var destroyGraphDiv = require('../assets/destroy_graph_div');
+var mouseEvent = require('../assets/mouse_event');
+
+
+describe('zoom box element', function() {
+    var mock = require('@mocks/14.json');
+
+    var gd;
+    beforeEach(function(done) {
+        gd = createGraphDiv();
+
+        var mockCopy = Lib.extendDeep({}, mock);
+        mockCopy.layout.dragmode = 'zoom';
+
+        Plotly.plot(gd, mockCopy.data, mockCopy.layout).then(done);
+    });
+
+    afterEach(destroyGraphDiv);
+
+    it('should be appended to the zoom layer', function() {
+        var x0 = 100;
+        var y0 = 200;
+        var x1 = 150;
+        var y1 = 200;
+
+        mouseEvent('mousemove', x0, y0);
+        expect(d3.selectAll('.zoomlayer > .zoombox').size())
+            .toEqual(0);
+        expect(d3.selectAll('.zoomlayer > .zoombox-corners').size())
+            .toEqual(0);
+
+        mouseEvent('mousedown', x0, y0);
+        mouseEvent('mousemove', x1, y1);
+        expect(d3.selectAll('.zoomlayer > .zoombox').size())
+            .toEqual(1);
+        expect(d3.selectAll('.zoomlayer > .zoombox-corners').size())
+            .toEqual(1);
+
+        mouseEvent('mouseup', x1, y1);
+        expect(d3.selectAll('.zoomlayer > .zoombox').size())
+            .toEqual(0);
+        expect(d3.selectAll('.zoomlayer > .zoombox-corners').size())
+            .toEqual(0);
+    });
+});