Implement Tour.hide

Closes [#249](#249).

src/js/step.js

@@ -292,10 +292,10 @@ export class Step extends Evented {
 
   /**
    * Check if the step is open and visible
-   * @return {*|boolean} True if the step is open and visible
+   * @return {boolean} True if the step is open and visible
    */
   isOpen() {
-    return this.el && !this.el.hidden;
+    return Boolean(this.el && !this.el.hidden);
   }
 
   /**

src/js/tour.js

@@ -148,6 +148,17 @@ export class Tour extends Evented {
     return this.currentStep;
   }
 
+  /**
+   * Hide the current step
+   */
+  hide() {
+    const currentStep = this.getCurrentStep();
+
+    if (currentStep && typeof currentStep.hide === 'function') {
+      return currentStep.hide();
+    }
+  }
+
   /**
    * Go to the next step in the tour
    * If we are at the end, call `complete`

test/unit/test.tour.js

@@ -147,6 +147,24 @@ describe('Tour', function() {
       });
     });
 
+    describe('.hide()', function() {
+      it('hides the current step', () => {
+        const firstStep = instance.steps[0];
+        const hideStepSpy = spy(firstStep, 'hide');
+
+        assert.equal(firstStep.isOpen(), false);
+
+        instance.start();
+
+        assert.equal(firstStep.isOpen(), true);
+
+        instance.hide();
+
+        assert.equal(firstStep.isOpen(), false);
+        assert.equal(hideStepSpy.callCount, 1);
+      });
+    });
+
     describe('.next()/.back()', function() {
       it('goes to the next/previous steps', function() {
         instance.start();