[dotnet] Allow setting of PageDimensions and PageMargins in PrintOptions directly

dotnet/src/webdriver/PrintOptions.cs

@@ -101,19 +101,27 @@ public bool ShrinkToFit
         }
 
         /// <summary>
-        /// Gets the dimensions for each page in the printed document.
+        /// Gets or sets the dimensions for each page in the printed document.
         /// </summary>
         public PageSize PageDimensions
         {
             get { return pageSize; }
+            set
+            {
+                pageSize = value ?? throw new ArgumentNullException(nameof(value));
+            }
         }
 
         /// <summary>
-        /// Gets the margins for each page in the doucment.
+        /// Gets or sets the margins for each page in the doucment.
         /// </summary>
         public Margins PageMargins
         {
             get { return margins; }
+            set
+            {
+                margins = value ?? throw new ArgumentNullException(nameof(value));
+            }
         }
 
         /// <summary>

dotnet/test/common/DriverTestFixture.cs

@@ -88,6 +88,8 @@ public abstract class DriverTestFixture
         public string scrollFrameOutOfViewport = EnvironmentManager.Instance.UrlBuilder.WhereIs("scrolling_tests/frame_with_nested_scrolling_frame_out_of_view.html");
         public string scrollFrameInViewport = EnvironmentManager.Instance.UrlBuilder.WhereIs("scrolling_tests/frame_with_nested_scrolling_frame.html");
 
+        public string printPage = EnvironmentManager.Instance.UrlBuilder.WhereIs("printPage.html");
+
         protected IWebDriver driver;
 
         public IWebDriver DriverInstance

dotnet/test/common/PrintTest.cs

@@ -0,0 +1,74 @@
+using NUnit.Framework;
+using System;
+
+namespace OpenQA.Selenium
+{
+    [TestFixture]
+    public class PrintTest : DriverTestFixture
+    {
+        private const string MagicString = "JVBER";
+        private ISupportsPrint printer;
+
+        [SetUp]
+        public void LocalSetUp()
+        {
+            Assert.That(driver, Is.InstanceOf<ISupportsPrint>(), $"Driver does not support {nameof(ISupportsPrint)}.");
+
+            printer = driver as ISupportsPrint;
+
+            driver.Navigate().GoToUrl(this.printPage);
+        }
+
+        [Test]
+        public void CanPrintPage()
+        {
+            var pdf = printer.Print(new PrintOptions());
+
+            Assert.That(pdf.AsBase64EncodedString, Does.Contain(MagicString));
+        }
+
+        [Test]
+        public void CanPrintTwoPages()
+        {
+            var options = new PrintOptions();
+
+            options.AddPageRangeToPrint("1-2");
+
+            var pdf = printer.Print(options);
+
+            Assert.That(pdf.AsBase64EncodedString, Does.Contain(MagicString));
+        }
+
+        [Test]
+        public void CanPrintWithMostParams()
+        {
+            var options = new PrintOptions()
+            {
+                Orientation = PrintOrientation.Landscape,
+                ScaleFactor = 0.5,
+                PageDimensions = new PrintOptions.PageSize { Width = 200, Height = 100 },
+                PageMargins = new PrintOptions.Margins { Top = 1, Bottom = 1, Left = 2, Right = 2 },
+                OutputBackgroundImages = true,
+                ShrinkToFit = false
+            };
+
+            options.AddPageRangeToPrint("1-3");
+
+            var pdf = printer.Print(options);
+
+            Assert.That(pdf.AsBase64EncodedString, Does.Contain(MagicString));
+        }
+
+        [Test]
+        public void PageSizeCannotBeNull()
+        {
+            Assert.That(() => new PrintOptions { PageDimensions = null }, Throws.InstanceOf<ArgumentNullException>());
+        }
+
+        [Test]
+        public void MarginsCannotBeNull()
+        {
+            Assert.That(() => new PrintOptions { PageMargins = null }, Throws.InstanceOf<ArgumentNullException>());
+        }
+    }
+}