[dotnet] Annotate nullability on Actions type (SeleniumHQ#15208)

RenderMichael · sandeepsuryaprasad · commit 72ad85a1c2b6 · 2025-03-23T15:07:34.000+05:30
* [dotnet] Annotate nullability on `Actions` type

* Add `Keys` nullability
diff --git a/dotnet/src/webdriver/Interactions/Actions.cs b/dotnet/src/webdriver/Interactions/Actions.cs
@@ -19,6 +19,9 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+
+#nullable enable
 
 namespace OpenQA.Selenium.Interactions
 {
@@ -29,9 +32,9 @@ public class Actions : IAction
     {
         private readonly TimeSpan duration;
         private ActionBuilder actionBuilder = new ActionBuilder();
-        private PointerInputDevice activePointer;
-        private KeyInputDevice activeKeyboard;
-        private WheelInputDevice activeWheel;
+        private PointerInputDevice? activePointer;
+        private KeyInputDevice? activeKeyboard;
+        private WheelInputDevice? activeWheel;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="Actions"/> class.
@@ -51,14 +54,10 @@ public Actions(IWebDriver driver)
         /// <exception cref="ArgumentException">If <paramref name="driver"/> does not implement <see cref="IActionExecutor"/>.</exception>
         public Actions(IWebDriver driver, TimeSpan duration)
         {
-            IActionExecutor actionExecutor = GetDriverAs<IActionExecutor>(driver);
-            if (actionExecutor == null)
-            {
-                throw new ArgumentException("The IWebDriver object must implement or wrap a driver that implements IActionExecutor.", nameof(driver));
-            }
+            IActionExecutor actionExecutor = GetDriverAs<IActionExecutor>(driver)
+                ?? throw new ArgumentException("The IWebDriver object must implement or wrap a driver that implements IActionExecutor.", nameof(driver));
 
             this.ActionExecutor = actionExecutor;
-
             this.duration = duration;
         }
 
@@ -74,9 +73,10 @@ public Actions(IWebDriver driver, TimeSpan duration)
         /// <param name="name">The name of the pointer device to set as active.</param>
         /// <returns>A self-reference to this Actions class.</returns>
         /// <exception cref="InvalidOperationException">If a device with this name exists but is not a pointer.</exception>
+        [MemberNotNull(nameof(activePointer))]
         public Actions SetActivePointer(PointerKind kind, string name)
         {
-            InputDevice device = FindDeviceById(name);
+            InputDevice? device = FindDeviceById(name);
 
             this.activePointer = device switch
             {
@@ -94,9 +94,10 @@ public Actions SetActivePointer(PointerKind kind, string name)
         /// <param name="name">The name of the keyboard device to set as active.</param>
         /// <returns>A self-reference to this Actions class.</returns>
         /// <exception cref="InvalidOperationException">If a device with this name exists but is not a keyboard.</exception>
+        [MemberNotNull(nameof(activeKeyboard))]
         public Actions SetActiveKeyboard(string name)
         {
-            InputDevice device = FindDeviceById(name);
+            InputDevice? device = FindDeviceById(name);
 
             this.activeKeyboard = device switch
             {
@@ -114,9 +115,10 @@ public Actions SetActiveKeyboard(string name)
         /// <param name="name">The name of the wheel device to set as active.</param>
         /// <returns>A self-reference to this Actions class.</returns>
         /// <exception cref="InvalidOperationException">If a device with this name exists but is not a wheel.</exception>
+        [MemberNotNull(nameof(activeWheel))]
         public Actions SetActiveWheel(string name)
         {
-            InputDevice device = FindDeviceById(name);
+            InputDevice? device = FindDeviceById(name);
 
             this.activeWheel = device switch
             {
@@ -128,7 +130,7 @@ public Actions SetActiveWheel(string name)
             return this;
         }
 
-        private InputDevice FindDeviceById(string name)
+        private InputDevice? FindDeviceById(string? name)
         {
             foreach (var sequence in this.actionBuilder.ToActionSequenceList())
             {
@@ -211,14 +213,14 @@ public Actions KeyDown(string theKey)
         /// of <see cref="Keys.Shift"/>, <see cref="Keys.Control"/>, <see cref="Keys.Alt"/>,
         /// <see cref="Keys.Meta"/>, <see cref="Keys.Command"/>,<see cref="Keys.LeftAlt"/>,
         /// <see cref="Keys.LeftControl"/>,<see cref="Keys.LeftShift"/>.</exception>
-        public Actions KeyDown(IWebElement element, string theKey)
+        public Actions KeyDown(IWebElement? element, string theKey)
         {
             if (string.IsNullOrEmpty(theKey))
             {
                 throw new ArgumentException("The key value must not be null or empty", nameof(theKey));
             }
 
-            ILocatable target = GetLocatableFromElement(element);
+            ILocatable? target = GetLocatableFromElement(element);
             if (element != null)
             {
                 this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));
@@ -255,14 +257,14 @@ public Actions KeyUp(string theKey)
         /// of <see cref="Keys.Shift"/>, <see cref="Keys.Control"/>, <see cref="Keys.Alt"/>,
         /// <see cref="Keys.Meta"/>, <see cref="Keys.Command"/>,<see cref="Keys.LeftAlt"/>,
         /// <see cref="Keys.LeftControl"/>,<see cref="Keys.LeftShift"/>.</exception>
-        public Actions KeyUp(IWebElement element, string theKey)
+        public Actions KeyUp(IWebElement? element, string theKey)
         {
             if (string.IsNullOrEmpty(theKey))
             {
                 throw new ArgumentException("The key value must not be null or empty", nameof(theKey));
             }
 
-            ILocatable target = GetLocatableFromElement(element);
+            ILocatable? target = GetLocatableFromElement(element);
             if (element != null)
             {
                 this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));
@@ -279,6 +281,7 @@ public Actions KeyUp(IWebElement element, string theKey)
         /// </summary>
         /// <param name="keysToSend">The keystrokes to send to the browser.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentException">If <paramref name="keysToSend"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
         public Actions SendKeys(string keysToSend)
         {
             return this.SendKeys(null, keysToSend);
@@ -290,14 +293,15 @@ public Actions SendKeys(string keysToSend)
         /// <param name="element">The element to which to send the keystrokes.</param>
         /// <param name="keysToSend">The keystrokes to send to the browser.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
-        public Actions SendKeys(IWebElement element, string keysToSend)
+        /// <exception cref="ArgumentException">If <paramref name="keysToSend"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>
+        public Actions SendKeys(IWebElement? element, string keysToSend)
         {
             if (string.IsNullOrEmpty(keysToSend))
             {
                 throw new ArgumentException("The key value must not be null or empty", nameof(keysToSend));
             }
 
-            ILocatable target = GetLocatableFromElement(element);
+            ILocatable? target = GetLocatableFromElement(element);
             if (element != null)
             {
                 this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));
@@ -319,6 +323,7 @@ public Actions SendKeys(IWebElement element, string keysToSend)
         /// </summary>
         /// <param name="onElement">The element on which to click and hold.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>
         public Actions ClickAndHold(IWebElement onElement)
         {
             this.MoveToElement(onElement).ClickAndHold();
@@ -340,6 +345,7 @@ public Actions ClickAndHold()
         /// </summary>
         /// <param name="onElement">The element on which to release the button.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>
         public Actions Release(IWebElement onElement)
         {
             this.MoveToElement(onElement).Release();
@@ -361,6 +367,7 @@ public Actions Release()
         /// </summary>
         /// <param name="onElement">The element on which to click.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>
         public Actions Click(IWebElement onElement)
         {
             this.MoveToElement(onElement).Click();
@@ -383,6 +390,7 @@ public Actions Click()
         /// </summary>
         /// <param name="onElement">The element on which to double-click.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>
         public Actions DoubleClick(IWebElement onElement)
         {
             this.MoveToElement(onElement).DoubleClick();
@@ -407,6 +415,7 @@ public Actions DoubleClick()
         /// </summary>
         /// <param name="toElement">The element to which to move the mouse.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="toElement"/> is null.</exception>
         public Actions MoveToElement(IWebElement toElement)
         {
             if (toElement == null)
@@ -460,6 +469,7 @@ public Actions MoveToLocation(int offsetX, int offsetY)
         /// </summary>
         /// <param name="onElement">The element on which to right-click.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>
         public Actions ContextClick(IWebElement onElement)
         {
             this.MoveToElement(onElement).ContextClick();
@@ -483,6 +493,7 @@ public Actions ContextClick()
         /// <param name="source">The element on which the drag operation is started.</param>
         /// <param name="target">The element on which the drop is performed.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="source"/> or <paramref name="target"/> are null.</exception>
         public Actions DragAndDrop(IWebElement source, IWebElement target)
         {
             this.ClickAndHold(source).MoveToElement(target).Release(target);
@@ -496,6 +507,7 @@ public Actions DragAndDrop(IWebElement source, IWebElement target)
         /// <param name="offsetX">The horizontal offset to which to move the mouse.</param>
         /// <param name="offsetY">The vertical offset to which to move the mouse.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="source"/> is null.</exception>
         public Actions DragAndDropToOffset(IWebElement source, int offsetX, int offsetY)
         {
             this.ClickAndHold(source).MoveByOffset(offsetX, offsetY).Release();
@@ -507,6 +519,7 @@ public Actions DragAndDropToOffset(IWebElement source, int offsetX, int offsetY)
         /// </summary>
         /// <param name="element">Which element to scroll into the viewport.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="element"/> is null.</exception>
         public Actions ScrollToElement(IWebElement element)
         {
             this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(element, 0, 0, 0, 0, duration));
@@ -540,8 +553,15 @@ public Actions ScrollByAmount(int deltaX, int deltaY)
         /// <param name="deltaY">Distance along Y axis to scroll using the wheel. A negative value scrolls up.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
         /// <exception cref="MoveTargetOutOfBoundsException">If the origin with offset is outside the viewport.</exception>
+        /// <exception cref="ArgumentNullException">If <paramref name="scrollOrigin"/> is null.</exception>
+        /// <exception cref="ArgumentException">If both or either of Viewport and Element are set.</exception>
         public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int deltaX, int deltaY)
         {
+            if (scrollOrigin is null)
+            {
+                throw new ArgumentNullException(nameof(scrollOrigin));
+            }
+
             if (scrollOrigin.Viewport && scrollOrigin.Element != null)
             {
                 throw new ArgumentException("viewport can not be true if an element is defined.", nameof(scrollOrigin));
@@ -554,7 +574,7 @@ public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int
             }
             else
             {
-                this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(scrollOrigin.Element,
+                this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(scrollOrigin.Element!,
                     scrollOrigin.XOffset, scrollOrigin.YOffset, deltaX, deltaY, duration));
             }
 
@@ -566,6 +586,7 @@ public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int
         /// </summary>
         /// <param name="duration">How long to pause the action chain.</param>
         /// <returns>A self-reference to this <see cref="Actions"/>.</returns>
+        /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>
         public Actions Pause(TimeSpan duration)
         {
             this.actionBuilder.AddAction(new PauseInteraction(this.GetActivePointer(), duration));
@@ -603,15 +624,16 @@ public void Reset()
         /// </summary>
         /// <param name="element">The <see cref="IWebElement"/> to get the location of.</param>
         /// <returns>The <see cref="ILocatable"/> of the <see cref="IWebElement"/>.</returns>
-        protected static ILocatable GetLocatableFromElement(IWebElement element)
+        [return: NotNullIfNotNull(nameof(element))]
+        protected static ILocatable? GetLocatableFromElement(IWebElement? element)
         {
             if (element == null)
             {
                 return null;
             }
 
-            ILocatable target = null;
-            IWrapsElement wrapper = element as IWrapsElement;
+            ILocatable? target = null;
+            IWrapsElement? wrapper = element as IWrapsElement;
             while (wrapper != null)
             {
                 target = wrapper.WrappedElement as ILocatable;
@@ -631,12 +653,12 @@ protected static ILocatable GetLocatableFromElement(IWebElement element)
             return target;
         }
 
-        private T GetDriverAs<T>(IWebDriver driver) where T : class
+        private static T? GetDriverAs<T>(IWebDriver? driver) where T : class
         {
-            T driverAsType = driver as T;
+            T? driverAsType = driver as T;
             if (driverAsType == null)
             {
-                IWrapsDriver wrapper = driver as IWrapsDriver;
+                IWrapsDriver? wrapper = driver as IWrapsDriver;
                 while (wrapper != null)
                 {
                     driverAsType = wrapper.WrappedDriver as T;
diff --git a/dotnet/src/webdriver/Interactions/InputDevice.cs b/dotnet/src/webdriver/Interactions/InputDevice.cs
@@ -77,6 +77,7 @@ public Interaction CreatePause()
         /// of the pause. Note that <see cref="TimeSpan.Zero"/> pauses to synchronize
         /// with other action sequences for other devices.</param>
         /// <returns>The <see cref="Interaction"/> representing the action.</returns>
+        /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>
         public Interaction CreatePause(TimeSpan duration)
         {
             return new PauseInteraction(this, duration);
diff --git a/dotnet/src/webdriver/Interactions/PauseInteraction.cs b/dotnet/src/webdriver/Interactions/PauseInteraction.cs
@@ -46,6 +46,7 @@ public PauseInteraction(InputDevice sourceDevice)
         /// </summary>
         /// <param name="sourceDevice">The input device on which to execute the pause.</param>
         /// <param name="duration">The length of time to pause for.</param>
+        /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>
         public PauseInteraction(InputDevice sourceDevice, TimeSpan duration)
             : base(sourceDevice)
         {
diff --git a/dotnet/src/webdriver/Keys.cs b/dotnet/src/webdriver/Keys.cs
@@ -21,6 +21,8 @@
 using System.Collections.Generic;
 using System.Globalization;
 
+#nullable enable
+
 namespace OpenQA.Selenium
 {
     /// <summary>
@@ -352,13 +354,14 @@ public static class Keys
         /// </summary>
         public static readonly string ZenkakuHankaku = Convert.ToString(Convert.ToChar(0xE040, CultureInfo.InvariantCulture), CultureInfo.InvariantCulture);
 
-        private static Dictionary<string, string> descriptions;
+        private static Dictionary<string, string>? descriptions;
 
         /// <summary>
         /// Gets the description of a specific key.
         /// </summary>
         /// <param name="value">The key value for which to get the description.</param>
         /// <returns>The description of the key.</returns>
+        /// <exception cref="ArgumentNullException">If <paramref name="value"/> is <see langword="null"/>.</exception>
         internal static object GetDescription(string value)
         {
             if (descriptions == null)
@@ -423,9 +426,9 @@ internal static object GetDescription(string value)
                 descriptions.Add(ZenkakuHankaku, "Zenkaku Hankaku");
             }
 
-            if (descriptions.ContainsKey(value))
+            if (descriptions.TryGetValue(value, out string? description))
             {
-                return descriptions[value];
+                return description;
             }
 
             return value;

Original file line number	Diff line number	Diff line change
`@@ -19,6 +19,9 @@`
`19`	`19`
`20`	`20`	`using System;`
`21`	`21`	`using System.Collections.Generic;`
	`22`	`+using System.Diagnostics.CodeAnalysis;`
	`23`	`+`
	`24`	`+#nullable enable`
`22`	`25`
`23`	`26`	`namespace OpenQA.Selenium.Interactions`
`24`	`27`	`{`
`@@ -29,9 +32,9 @@ public class Actions : IAction`
`29`	`32`	`{`
`30`	`33`	`private readonly TimeSpan duration;`
`31`	`34`	`private ActionBuilder actionBuilder = new ActionBuilder();`
`32`		`- private PointerInputDevice activePointer;`
`33`		`- private KeyInputDevice activeKeyboard;`
`34`		`- private WheelInputDevice activeWheel;`
	`35`	`+ private PointerInputDevice? activePointer;`
	`36`	`+ private KeyInputDevice? activeKeyboard;`
	`37`	`+ private WheelInputDevice? activeWheel;`
`35`	`38`
`36`	`39`	`/// <summary>`
`37`	`40`	`/// Initializes a new instance of the <see cref="Actions"/> class.`
`@@ -51,14 +54,10 @@ public Actions(IWebDriver driver)`
`51`	`54`	`/// <exception cref="ArgumentException">If <paramref name="driver"/> does not implement <see cref="IActionExecutor"/>.</exception>`
`52`	`55`	`public Actions(IWebDriver driver, TimeSpan duration)`
`53`	`56`	`{`
`54`		`- IActionExecutor actionExecutor = GetDriverAs<IActionExecutor>(driver);`
`55`		`- if (actionExecutor == null)`
`56`		`- {`
`57`		`- throw new ArgumentException("The IWebDriver object must implement or wrap a driver that implements IActionExecutor.", nameof(driver));`
`58`		`- }`
	`57`	`+ IActionExecutor actionExecutor = GetDriverAs<IActionExecutor>(driver)`
	`58`	`+ ?? throw new ArgumentException("The IWebDriver object must implement or wrap a driver that implements IActionExecutor.", nameof(driver));`
`59`	`59`
`60`	`60`	`this.ActionExecutor = actionExecutor;`
`61`		`-`
`62`	`61`	`this.duration = duration;`
`63`	`62`	`}`
`64`	`63`
`@@ -74,9 +73,10 @@ public Actions(IWebDriver driver, TimeSpan duration)`
`74`	`73`	`/// <param name="name">The name of the pointer device to set as active.</param>`
`75`	`74`	`/// <returns>A self-reference to this Actions class.</returns>`
`76`	`75`	`/// <exception cref="InvalidOperationException">If a device with this name exists but is not a pointer.</exception>`
	`76`	`+ [MemberNotNull(nameof(activePointer))]`
`77`	`77`	`public Actions SetActivePointer(PointerKind kind, string name)`
`78`	`78`	`{`
`79`		`- InputDevice device = FindDeviceById(name);`
	`79`	`+ InputDevice? device = FindDeviceById(name);`
`80`	`80`
`81`	`81`	`this.activePointer = device switch`
`82`	`82`	`{`
`@@ -94,9 +94,10 @@ public Actions SetActivePointer(PointerKind kind, string name)`
`94`	`94`	`/// <param name="name">The name of the keyboard device to set as active.</param>`
`95`	`95`	`/// <returns>A self-reference to this Actions class.</returns>`
`96`	`96`	`/// <exception cref="InvalidOperationException">If a device with this name exists but is not a keyboard.</exception>`
	`97`	`+ [MemberNotNull(nameof(activeKeyboard))]`
`97`	`98`	`public Actions SetActiveKeyboard(string name)`
`98`	`99`	`{`
`99`		`- InputDevice device = FindDeviceById(name);`
	`100`	`+ InputDevice? device = FindDeviceById(name);`
`100`	`101`
`101`	`102`	`this.activeKeyboard = device switch`
`102`	`103`	`{`
`@@ -114,9 +115,10 @@ public Actions SetActiveKeyboard(string name)`
`114`	`115`	`/// <param name="name">The name of the wheel device to set as active.</param>`
`115`	`116`	`/// <returns>A self-reference to this Actions class.</returns>`
`116`	`117`	`/// <exception cref="InvalidOperationException">If a device with this name exists but is not a wheel.</exception>`
	`118`	`+ [MemberNotNull(nameof(activeWheel))]`
`117`	`119`	`public Actions SetActiveWheel(string name)`
`118`	`120`	`{`
`119`		`- InputDevice device = FindDeviceById(name);`
	`121`	`+ InputDevice? device = FindDeviceById(name);`
`120`	`122`
`121`	`123`	`this.activeWheel = device switch`
`122`	`124`	`{`
`@@ -128,7 +130,7 @@ public Actions SetActiveWheel(string name)`
`128`	`130`	`return this;`
`129`	`131`	`}`
`130`	`132`
`131`		`- private InputDevice FindDeviceById(string name)`
	`133`	`+ private InputDevice? FindDeviceById(string? name)`
`132`	`134`	`{`
`133`	`135`	`foreach (var sequence in this.actionBuilder.ToActionSequenceList())`
`134`	`136`	`{`
`@@ -211,14 +213,14 @@ public Actions KeyDown(string theKey)`
`211`	`213`	`/// of <see cref="Keys.Shift"/>, <see cref="Keys.Control"/>, <see cref="Keys.Alt"/>,`
`212`	`214`	`/// <see cref="Keys.Meta"/>, <see cref="Keys.Command"/>,<see cref="Keys.LeftAlt"/>,`
`213`	`215`	`/// <see cref="Keys.LeftControl"/>,<see cref="Keys.LeftShift"/>.</exception>`
`214`		`- public Actions KeyDown(IWebElement element, string theKey)`
	`216`	`+ public Actions KeyDown(IWebElement? element, string theKey)`
`215`	`217`	`{`
`216`	`218`	`if (string.IsNullOrEmpty(theKey))`
`217`	`219`	`{`
`218`	`220`	`throw new ArgumentException("The key value must not be null or empty", nameof(theKey));`
`219`	`221`	`}`
`220`	`222`
`221`		`- ILocatable target = GetLocatableFromElement(element);`
	`223`	`+ ILocatable? target = GetLocatableFromElement(element);`
`222`	`224`	`if (element != null)`
`223`	`225`	`{`
`224`	`226`	`this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));`
`@@ -255,14 +257,14 @@ public Actions KeyUp(string theKey)`
`255`	`257`	`/// of <see cref="Keys.Shift"/>, <see cref="Keys.Control"/>, <see cref="Keys.Alt"/>,`
`256`	`258`	`/// <see cref="Keys.Meta"/>, <see cref="Keys.Command"/>,<see cref="Keys.LeftAlt"/>,`
`257`	`259`	`/// <see cref="Keys.LeftControl"/>,<see cref="Keys.LeftShift"/>.</exception>`
`258`		`- public Actions KeyUp(IWebElement element, string theKey)`
	`260`	`+ public Actions KeyUp(IWebElement? element, string theKey)`
`259`	`261`	`{`
`260`	`262`	`if (string.IsNullOrEmpty(theKey))`
`261`	`263`	`{`
`262`	`264`	`throw new ArgumentException("The key value must not be null or empty", nameof(theKey));`
`263`	`265`	`}`
`264`	`266`
`265`		`- ILocatable target = GetLocatableFromElement(element);`
	`267`	`+ ILocatable? target = GetLocatableFromElement(element);`
`266`	`268`	`if (element != null)`
`267`	`269`	`{`
`268`	`270`	`this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));`
`@@ -279,6 +281,7 @@ public Actions KeyUp(IWebElement element, string theKey)`
`279`	`281`	`/// </summary>`
`280`	`282`	`/// <param name="keysToSend">The keystrokes to send to the browser.</param>`
`281`	`283`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`284`	`+ /// <exception cref="ArgumentException">If <paramref name="keysToSend"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>`
`282`	`285`	`public Actions SendKeys(string keysToSend)`
`283`	`286`	`{`
`284`	`287`	`return this.SendKeys(null, keysToSend);`
`@@ -290,14 +293,15 @@ public Actions SendKeys(string keysToSend)`
`290`	`293`	`/// <param name="element">The element to which to send the keystrokes.</param>`
`291`	`294`	`/// <param name="keysToSend">The keystrokes to send to the browser.</param>`
`292`	`295`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
`293`		`- public Actions SendKeys(IWebElement element, string keysToSend)`
	`296`	`+ /// <exception cref="ArgumentException">If <paramref name="keysToSend"/> is <see langword="null"/> or <see cref="string.Empty"/>.</exception>`
	`297`	`+ public Actions SendKeys(IWebElement? element, string keysToSend)`
`294`	`298`	`{`
`295`	`299`	`if (string.IsNullOrEmpty(keysToSend))`
`296`	`300`	`{`
`297`	`301`	`throw new ArgumentException("The key value must not be null or empty", nameof(keysToSend));`
`298`	`302`	`}`
`299`	`303`
`300`		`- ILocatable target = GetLocatableFromElement(element);`
	`304`	`+ ILocatable? target = GetLocatableFromElement(element);`
`301`	`305`	`if (element != null)`
`302`	`306`	`{`
`303`	`307`	`this.actionBuilder.AddAction(this.GetActivePointer().CreatePointerMove(element, 0, 0, duration));`
`@@ -319,6 +323,7 @@ public Actions SendKeys(IWebElement element, string keysToSend)`
`319`	`323`	`/// </summary>`
`320`	`324`	`/// <param name="onElement">The element on which to click and hold.</param>`
`321`	`325`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`326`	`+ /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>`
`322`	`327`	`public Actions ClickAndHold(IWebElement onElement)`
`323`	`328`	`{`
`324`	`329`	`this.MoveToElement(onElement).ClickAndHold();`
`@@ -340,6 +345,7 @@ public Actions ClickAndHold()`
`340`	`345`	`/// </summary>`
`341`	`346`	`/// <param name="onElement">The element on which to release the button.</param>`
`342`	`347`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`348`	`+ /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>`
`343`	`349`	`public Actions Release(IWebElement onElement)`
`344`	`350`	`{`
`345`	`351`	`this.MoveToElement(onElement).Release();`
`@@ -361,6 +367,7 @@ public Actions Release()`
`361`	`367`	`/// </summary>`
`362`	`368`	`/// <param name="onElement">The element on which to click.</param>`
`363`	`369`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`370`	`+ /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>`
`364`	`371`	`public Actions Click(IWebElement onElement)`
`365`	`372`	`{`
`366`	`373`	`this.MoveToElement(onElement).Click();`
`@@ -383,6 +390,7 @@ public Actions Click()`
`383`	`390`	`/// </summary>`
`384`	`391`	`/// <param name="onElement">The element on which to double-click.</param>`
`385`	`392`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`393`	`+ /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>`
`386`	`394`	`public Actions DoubleClick(IWebElement onElement)`
`387`	`395`	`{`
`388`	`396`	`this.MoveToElement(onElement).DoubleClick();`
`@@ -407,6 +415,7 @@ public Actions DoubleClick()`
`407`	`415`	`/// </summary>`
`408`	`416`	`/// <param name="toElement">The element to which to move the mouse.</param>`
`409`	`417`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`418`	`+ /// <exception cref="ArgumentNullException">If <paramref name="toElement"/> is null.</exception>`
`410`	`419`	`public Actions MoveToElement(IWebElement toElement)`
`411`	`420`	`{`
`412`	`421`	`if (toElement == null)`
`@@ -460,6 +469,7 @@ public Actions MoveToLocation(int offsetX, int offsetY)`
`460`	`469`	`/// </summary>`
`461`	`470`	`/// <param name="onElement">The element on which to right-click.</param>`
`462`	`471`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`472`	`+ /// <exception cref="ArgumentNullException">If <paramref name="onElement"/> is null.</exception>`
`463`	`473`	`public Actions ContextClick(IWebElement onElement)`
`464`	`474`	`{`
`465`	`475`	`this.MoveToElement(onElement).ContextClick();`
`@@ -483,6 +493,7 @@ public Actions ContextClick()`
`483`	`493`	`/// <param name="source">The element on which the drag operation is started.</param>`
`484`	`494`	`/// <param name="target">The element on which the drop is performed.</param>`
`485`	`495`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`496`	`+ /// <exception cref="ArgumentNullException">If <paramref name="source"/> or <paramref name="target"/> are null.</exception>`
`486`	`497`	`public Actions DragAndDrop(IWebElement source, IWebElement target)`
`487`	`498`	`{`
`488`	`499`	`this.ClickAndHold(source).MoveToElement(target).Release(target);`
`@@ -496,6 +507,7 @@ public Actions DragAndDrop(IWebElement source, IWebElement target)`
`496`	`507`	`/// <param name="offsetX">The horizontal offset to which to move the mouse.</param>`
`497`	`508`	`/// <param name="offsetY">The vertical offset to which to move the mouse.</param>`
`498`	`509`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`510`	`+ /// <exception cref="ArgumentNullException">If <paramref name="source"/> is null.</exception>`
`499`	`511`	`public Actions DragAndDropToOffset(IWebElement source, int offsetX, int offsetY)`
`500`	`512`	`{`
`501`	`513`	`this.ClickAndHold(source).MoveByOffset(offsetX, offsetY).Release();`
`@@ -507,6 +519,7 @@ public Actions DragAndDropToOffset(IWebElement source, int offsetX, int offsetY)`
`507`	`519`	`/// </summary>`
`508`	`520`	`/// <param name="element">Which element to scroll into the viewport.</param>`
`509`	`521`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`522`	`+ /// <exception cref="ArgumentNullException">If <paramref name="element"/> is null.</exception>`
`510`	`523`	`public Actions ScrollToElement(IWebElement element)`
`511`	`524`	`{`
`512`	`525`	`this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(element, 0, 0, 0, 0, duration));`
`@@ -540,8 +553,15 @@ public Actions ScrollByAmount(int deltaX, int deltaY)`
`540`	`553`	`/// <param name="deltaY">Distance along Y axis to scroll using the wheel. A negative value scrolls up.</param>`
`541`	`554`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
`542`	`555`	`/// <exception cref="MoveTargetOutOfBoundsException">If the origin with offset is outside the viewport.</exception>`
	`556`	`+ /// <exception cref="ArgumentNullException">If <paramref name="scrollOrigin"/> is null.</exception>`
	`557`	`+ /// <exception cref="ArgumentException">If both or either of Viewport and Element are set.</exception>`
`543`	`558`	`public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int deltaX, int deltaY)`
`544`	`559`	`{`
	`560`	`+ if (scrollOrigin is null)`
	`561`	`+ {`
	`562`	`+ throw new ArgumentNullException(nameof(scrollOrigin));`
	`563`	`+ }`
	`564`	`+`
`545`	`565`	`if (scrollOrigin.Viewport && scrollOrigin.Element != null)`
`546`	`566`	`{`
`547`	`567`	`throw new ArgumentException("viewport can not be true if an element is defined.", nameof(scrollOrigin));`
`@@ -554,7 +574,7 @@ public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int`
`554`	`574`	`}`
`555`	`575`	`else`
`556`	`576`	`{`
`557`		`- this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(scrollOrigin.Element,`
	`577`	`+ this.actionBuilder.AddAction(this.GetActiveWheel().CreateWheelScroll(scrollOrigin.Element!,`
`558`	`578`	`scrollOrigin.XOffset, scrollOrigin.YOffset, deltaX, deltaY, duration));`
`559`	`579`	`}`
`560`	`580`
`@@ -566,6 +586,7 @@ public Actions ScrollFromOrigin(WheelInputDevice.ScrollOrigin scrollOrigin, int`
`566`	`586`	`/// </summary>`
`567`	`587`	`/// <param name="duration">How long to pause the action chain.</param>`
`568`	`588`	`/// <returns>A self-reference to this <see cref="Actions"/>.</returns>`
	`589`	`+ /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>`
`569`	`590`	`public Actions Pause(TimeSpan duration)`
`570`	`591`	`{`
`571`	`592`	`this.actionBuilder.AddAction(new PauseInteraction(this.GetActivePointer(), duration));`
`@@ -603,15 +624,16 @@ public void Reset()`
`603`	`624`	`/// </summary>`
`604`	`625`	`/// <param name="element">The <see cref="IWebElement"/> to get the location of.</param>`
`605`	`626`	`/// <returns>The <see cref="ILocatable"/> of the <see cref="IWebElement"/>.</returns>`
`606`		`- protected static ILocatable GetLocatableFromElement(IWebElement element)`
	`627`	`+ [return: NotNullIfNotNull(nameof(element))]`
	`628`	`+ protected static ILocatable? GetLocatableFromElement(IWebElement? element)`
`607`	`629`	`{`
`608`	`630`	`if (element == null)`
`609`	`631`	`{`
`610`	`632`	`return null;`
`611`	`633`	`}`
`612`	`634`
`613`		`- ILocatable target = null;`
`614`		`- IWrapsElement wrapper = element as IWrapsElement;`
	`635`	`+ ILocatable? target = null;`
	`636`	`+ IWrapsElement? wrapper = element as IWrapsElement;`
`615`	`637`	`while (wrapper != null)`
`616`	`638`	`{`
`617`	`639`	`target = wrapper.WrappedElement as ILocatable;`
`@@ -631,12 +653,12 @@ protected static ILocatable GetLocatableFromElement(IWebElement element)`
`631`	`653`	`return target;`
`632`	`654`	`}`
`633`	`655`
`634`		`- private T GetDriverAs<T>(IWebDriver driver) where T : class`
	`656`	`+ private static T? GetDriverAs<T>(IWebDriver? driver) where T : class`
`635`	`657`	`{`
`636`		`- T driverAsType = driver as T;`
	`658`	`+ T? driverAsType = driver as T;`
`637`	`659`	`if (driverAsType == null)`
`638`	`660`	`{`
`639`		`- IWrapsDriver wrapper = driver as IWrapsDriver;`
	`661`	`+ IWrapsDriver? wrapper = driver as IWrapsDriver;`
`640`	`662`	`while (wrapper != null)`
`641`	`663`	`{`
`642`	`664`	`driverAsType = wrapper.WrappedDriver as T;`
Original file line number	Diff line number	Diff line change
`@@ -77,6 +77,7 @@ public Interaction CreatePause()`
`77`	`77`	`/// of the pause. Note that <see cref="TimeSpan.Zero"/> pauses to synchronize`
`78`	`78`	`/// with other action sequences for other devices.</param>`
`79`	`79`	`/// <returns>The <see cref="Interaction"/> representing the action.</returns>`
	`80`	`+ /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>`
`80`	`81`	`public Interaction CreatePause(TimeSpan duration)`
`81`	`82`	`{`
`82`	`83`	`return new PauseInteraction(this, duration);`
Original file line number	Diff line number	Diff line change
`@@ -46,6 +46,7 @@ public PauseInteraction(InputDevice sourceDevice)`
`46`	`46`	`/// </summary>`
`47`	`47`	`/// <param name="sourceDevice">The input device on which to execute the pause.</param>`
`48`	`48`	`/// <param name="duration">The length of time to pause for.</param>`
	`49`	`+ /// <exception cref="ArgumentException">If <paramref name="duration"/> is negative.</exception>`
`49`	`50`	`public PauseInteraction(InputDevice sourceDevice, TimeSpan duration)`
`50`	`51`	`: base(sourceDevice)`
`51`	`52`	`{`