Added seeNumberOfTabs method (#77)

Author: DavertMik

src/Codeception/Module/WebDriver.php

@@ -3430,6 +3430,20 @@ public function openNewTab()
         $this->switchToNextTab();
     }
 
+    /**
+     * Checks current number of opened tabs
+     *
+     * ```php
+     * <?php
+     * $I->seeNumberOfTabs(2);
+     * ```
+     * @param $number number of tabs
+     */
+    public function seeNumberOfTabs($number)
+    {
+        $this->assertEquals(count($this->webDriver->getWindowHandles()), $number);
+    }    
+
     /**
      * Closes current browser tab and switches to previous active tab.
      *

tests/web/WebDriverTest.php

@@ -393,12 +393,14 @@ public function testAppendFieldText()
 
     public function testTypeOnTextField()
     {
+
         $this->module->amOnPage('/form/field');
         $this->module->fillField('form #name', '');
         $this->module->type('Hello world');
         $this->module->click('Submit');
         $form = data::get('form');
         $this->assertEquals('Hello world', $form['name']);
+
     }
 
     public function testAppendFieldTextFails()
@@ -1033,6 +1035,7 @@ public function testBrowserTabs()
         $this->module->seeInCurrentUrl('example2');
         $this->module->switchToNextTab(2);
         $this->module->seeInCurrentUrl('example1');
+        $this->module->seeNumberOfTabs(3);
     }
 
     public function testPerformOnWithArray()