Support Finding of Multiple elements from ShadowRoot (#236)

* Support Finding of Multiple elements from ShadowRoot
- add JavaScript to generate CSS selector from element
- try to generate CSS selector if XPath generation fails - necessary for ShadowRoot elements since

* Replace GetElementCssSelector for old browsers compatibility (like InternetExplorer)

* refactor JavaScript function to generate CSS selector from element

* Refactoring, Introduce IShadowRootExpander interface to reduce duplication

* move common code to IShadowRootExpander extensions to reduce duplications

* Fix locator generation in case when generated XPath was invalid (e.g. when use FindElements with By.Id  or By.ClassName locator)

* Update ElementFactory to use Generate CSS locator logic in GenerateLocator method instead of GenerateXPathLocator

Aquality.Selenium/src/Aquality.Selenium/Aquality.Selenium.csproj

@@ -25,6 +25,7 @@
 
   <ItemGroup>
     <None Remove="Resources\JavaScripts\ExpandShadowRoot.js" />
+    <None Remove="Resources\JavaScripts\GetElementCssSelector.js" />
     <None Remove="Resources\JavaScripts\SetAttribute.js" />
     <None Remove="Resources\Localization\be.json" />
     <None Remove="Resources\Localization\en.json" />
@@ -49,6 +50,7 @@
     <EmbeddedResource Include="Resources\JavaScripts\GetElementByXPath.js" />
     <EmbeddedResource Include="Resources\JavaScripts\ExpandShadowRoot.js" />
     <EmbeddedResource Include="Resources\JavaScripts\GetElementText.js" />
+    <EmbeddedResource Include="Resources\JavaScripts\GetElementCssSelector.js" />
     <EmbeddedResource Include="Resources\JavaScripts\GetElementXPath.js" />
     <EmbeddedResource Include="Resources\JavaScripts\GetTextFirstChild.js" />
     <EmbeddedResource Include="Resources\JavaScripts\GetViewPortCoordinates.js" />

Aquality.Selenium/src/Aquality.Selenium/Browsers/JavaScript.cs

@@ -18,6 +18,7 @@ public enum JavaScript
         GetElementByXPath,
         GetElementText,
         GetElementXPath,
+        GetElementCssSelector,
         GetTextFirstChild,
         IsPageLoaded,
         MouseHover,

Aquality.Selenium/src/Aquality.Selenium/Elements/Actions/JsActions.cs

@@ -5,7 +5,6 @@
 using System.Linq;
 using Aquality.Selenium.Browsers;
 using Aquality.Selenium.Configurations;
-using Aquality.Selenium.Core.Elements;
 using Aquality.Selenium.Core.Localization;
 using Aquality.Selenium.Core.Utilities;
 using Aquality.Selenium.Elements.Interfaces;
@@ -16,7 +15,7 @@ namespace Aquality.Selenium.Elements.Actions
     /// <summary>
     /// Allows to perform actions on elements via JavaScript.
     /// </summary>
-    public class JsActions
+    public class JsActions : IShadowRootExpander
     {
         private readonly IElement element;
         private readonly string elementType;
@@ -47,25 +46,7 @@ public ShadowRoot ExpandShadowRoot()
         }
 
         /// <summary>
-        /// Finds element in the shadow root of the current element.
-        /// </summary>
-        /// <typeparam name="T">Type of the target element that has to implement <see cref="IElement"/>.</typeparam>
-        /// <param name="locator">Locator of the target element. 
-        /// Note that some browsers don't support XPath locator for shadow elements (e.g. Chrome).</param>
-        /// <param name="name">Name of the target element.</param>
-        /// <param name="supplier">Delegate that defines constructor of element.</param>
-        /// <param name="state">State of the target element.</param>
-        /// <returns>Instance of element.</returns>
-        public T FindElementInShadowRoot<T>(By locator, string name, ElementSupplier<T> supplier = null, ElementState state = ElementState.Displayed)
-            where T : IElement
-        {
-            var shadowRootRelativeFinder = new RelativeElementFinder(Logger, AqualityServices.ConditionalWait, ExpandShadowRoot);
-            var shadowRootFactory = new ElementFactory(AqualityServices.ConditionalWait, shadowRootRelativeFinder, AqualityServices.Get<ILocalizationManager>());
-            return shadowRootFactory.Get(locator, name, supplier, state);
-        }
-
-        /// <summary>
-        /// Perfroms click on element and waits for page is loaded.
+        /// Performs click on element and waits for page is loaded.
         /// </summary>
         public void ClickAndWait()
         {

Aquality.Selenium/src/Aquality.Selenium/Elements/Element.cs

@@ -16,6 +16,7 @@
 using ICoreElementFactory = Aquality.Selenium.Core.Elements.Interfaces.IElementFactory;
 using ICoreElementFinder = Aquality.Selenium.Core.Elements.Interfaces.IElementFinder;
 using ICoreElementStateProvider = Aquality.Selenium.Core.Elements.Interfaces.IElementStateProvider;
+using System.Collections.Generic;
 
 namespace Aquality.Selenium.Elements
 {
@@ -134,13 +135,5 @@ public ShadowRoot ExpandShadowRoot()
             var shadowRoot = (ShadowRoot)GetElement().GetShadowRoot();
             return shadowRoot;
         }
-
-        public T FindElementInShadowRoot<T>(By locator, string name, ElementSupplier<T> supplier = null, ElementState state = ElementState.Displayed) 
-            where T : IElement
-        {
-            var shadowRootRelativeFinder = new RelativeElementFinder(LocalizedLogger, ConditionalWait, ExpandShadowRoot);
-            var shadowRootFactory = new ElementFactory(ConditionalWait, shadowRootRelativeFinder, LocalizationManager);
-            return shadowRootFactory.Get(locator, name, supplier, state);
-        }
     }
 }

Aquality.Selenium/src/Aquality.Selenium/Elements/ElementFactory.cs

@@ -113,6 +113,26 @@ protected override IDictionary<Type, Type> ElementTypesMap
             }
         }
 
+        /// <summary>
+        /// Generates locator for target element
+        /// </summary>
+        /// <param name="baseLocator">locator of parent element</param>
+        /// <param name="webElement">target element</param>
+        /// <param name="elementIndex">index of target element</param>
+        /// <returns>target element's locator</returns>
+        protected override By GenerateLocator(By baseLocator, IWebElement webElement, int elementIndex)
+        {
+            try
+            {
+                return GenerateXpathLocator(baseLocator, webElement, elementIndex);
+            }
+            catch (WebDriverException ex)
+            {
+                return By.CssSelector(ConditionalWait.WaitFor(driver => driver.ExecuteJavaScript<string>(
+                    JavaScript.GetElementCssSelector.GetScript(), webElement), message: $"{ex.Message}. CSS selector generation failed too."));
+            }
+        }
+
         /// <summary>
         /// Generates xpath locator for target element
         /// </summary>
@@ -122,10 +142,16 @@ protected override IDictionary<Type, Type> ElementTypesMap
         /// <returns>target element's locator</returns>
         protected override By GenerateXpathLocator(By baseLocator, IWebElement webElement, int elementIndex)
         {
-            return IsLocatorSupportedForXPathExtraction(baseLocator)
-                ? base.GenerateXpathLocator(baseLocator, webElement, elementIndex)
-                : By.XPath(ConditionalWait.WaitFor(driver => driver.ExecuteJavaScript<string>(
-                    JavaScript.GetElementXPath.GetScript(), webElement), message: "XPath generation failed"));
+            if (IsLocatorSupportedForXPathExtraction(baseLocator))
+            {
+                var locator = base.GenerateXpathLocator(baseLocator, webElement, elementIndex);
+                if (ElementFinder.FindElements(locator).Count == 1)
+                {
+                    return locator;
+                }
+            }
+            return By.XPath(ConditionalWait.WaitFor(driver => driver.ExecuteJavaScript<string>(
+                JavaScript.GetElementXPath.GetScript(), webElement), message: "XPath generation failed"));
         }
 
         /// <summary>

Aquality.Selenium/src/Aquality.Selenium/Elements/Interfaces/IElement.cs

@@ -1,14 +1,12 @@
-using Aquality.Selenium.Core.Elements;
-using Aquality.Selenium.Elements.Actions;
-using OpenQA.Selenium;
+using Aquality.Selenium.Elements.Actions;
 using ICoreElement = Aquality.Selenium.Core.Elements.Interfaces.IElement;
 
 namespace Aquality.Selenium.Elements.Interfaces
 {
     /// <summary>
     /// Describes behavior of any UI element.
     /// </summary>
-    public interface IElement : ICoreElement
+    public interface IElement : ICoreElement, IShadowRootExpander
     {
         /// <summary>
         /// Gets JavaScript actions that can be performed with an element.
@@ -74,24 +72,5 @@ public interface IElement : ICoreElement
         /// </summary>
         /// <param name="key"> Key for sending.</param>
         void SendKey(Key key);
-
-        /// <summary>
-        /// Expands shadow root.
-        /// </summary>
-        /// <returns><see cref="ShadowRoot"/> search context.</returns>
-        ShadowRoot ExpandShadowRoot();
-
-        /// <summary>
-        /// Finds element in the shadow root of the current element.
-        /// </summary>
-        /// <typeparam name="T">Type of the target element that has to implement <see cref="IElement"/>.</typeparam>
-        /// <param name="locator">Locator of the target element. 
-        /// Note that some browsers don't support XPath locator for shadow elements.</param>
-        /// <param name="name">Name of the target element.</param>
-        /// <param name="supplier">Delegate that defines constructor of element.</param>
-        /// <param name="state">State of the target element.</param>
-        /// <returns>Instance of element.</returns>
-        T FindElementInShadowRoot<T>(By locator, string name, ElementSupplier<T> supplier = null, ElementState state = ElementState.Displayed) 
-            where T : IElement;
     }
 }

Aquality.Selenium/src/Aquality.Selenium/Elements/Interfaces/IShadowRootExpander.cs

@@ -0,0 +1,71 @@
+using Aquality.Selenium.Browsers;
+using Aquality.Selenium.Core.Elements;
+using Aquality.Selenium.Core.Localization;
+using OpenQA.Selenium;
+using System.Collections.Generic;
+
+namespace Aquality.Selenium.Elements.Interfaces
+{
+    /// <summary>
+    /// Shadow Root expander.
+    /// </summary>
+    public interface IShadowRootExpander
+    {
+        /// <summary>
+        /// Expands shadow root.
+        /// </summary>
+        /// <returns>ShadowRoot search context.</returns>
+        ShadowRoot ExpandShadowRoot();
+    }
+
+    /// <summary>
+    /// Extensions for Shadow Root expander (like element or JS Actions).
+    /// </summary>
+    public static class ShadowRootExpanderExtensions
+    {
+        /// <summary>
+        /// Provides <see cref="IElementFactory"/> to find elements in the shadow root of the current element.
+        /// </summary>
+        public static IElementFactory GetShadowRootElementFactory(this IShadowRootExpander shadowRootExpander)
+        {
+            var shadowRootRelativeFinder = new RelativeElementFinder(AqualityServices.LocalizedLogger, AqualityServices.ConditionalWait, shadowRootExpander.ExpandShadowRoot);
+            return new ElementFactory(AqualityServices.ConditionalWait, shadowRootRelativeFinder, AqualityServices.Get<ILocalizationManager>());
+        }
+
+        /// <summary>
+        /// Finds element in the shadow root of the current element.
+        /// </summary>
+        /// <typeparam name="T">Type of the target element that has to implement <see cref="IElement"/>.</typeparam>
+        /// <param name="shadowRootExpander">Current instance of the Shadow root expander.</param>
+        /// <param name="locator">Locator of the target element. 
+        /// Note that some browsers don't support XPath locator for shadow elements (e.g. Chrome).</param>
+        /// <param name="name">Name of the target element.</param>
+        /// <param name="supplier">Delegate that defines constructor of element.</param>
+        /// <param name="state">State of the target element.</param>
+        /// <returns>Instance of element.</returns>
+        public static T FindElementInShadowRoot<T>(this IShadowRootExpander shadowRootExpander, By locator, string name, ElementSupplier<T> supplier = null, ElementState state = ElementState.Displayed)
+            where T : IElement
+        {
+            return shadowRootExpander.GetShadowRootElementFactory().Get(locator, name, supplier, state);
+        }
+
+        /// <summary>
+        /// Finds elements in the shadow root of the current element.
+        /// </summary>
+        /// <typeparam name="T">Type of the target elements that has to implement <see cref="IElement"/>.</typeparam>
+        /// <param name="shadowRootExpander">Current instance of the Shadow root expander.</param>
+        /// <param name="locator">Locator of target elements. 
+        /// Note that some browsers don't support XPath locator for shadow elements.
+        /// Therefore, we suggest to use CSS selectors</param>
+        /// <param name="name">Name of target elements.</param>
+        /// <param name="supplier">Delegate that defines constructor of element.</param>
+        /// <param name="expectedCount">Expected number of elements that have to be found (zero, more then zero, any).</param>
+        /// <param name="state">State of target elements.</param>
+        /// <returns>List of found elements.</returns>
+        public static IList<T> FindElementsInShadowRoot<T>(this IShadowRootExpander shadowRootExpander, By locator, string name = null, ElementSupplier<T> supplier = null, ElementsCount expectedCount = ElementsCount.Any, ElementState state = ElementState.Displayed)
+            where T : IElement
+        {
+            return shadowRootExpander.GetShadowRootElementFactory().FindElements(locator, name, supplier, expectedCount, state);
+        }
+    }
+}