Add support for await using by implementing IAsyncDisposable for Page and Browser. Fix #1456 (#1458)

Author: madelson

lib/PuppeteerSharp.Tests/PageTests/CloseTests.cs

@@ -1,4 +1,4 @@
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -24,11 +24,21 @@ await Task.WhenAll(
             Assert.Equal("Target.detachedFromTarget", exception.CloseReason);
         }
 
-        [Fact]
-        public async Task ShouldNotBeVisibleInBrowserPages()
+        [Theory]
+        [InlineData(false)]
+        [InlineData(true)]
+        public async Task ShouldNotBeVisibleInBrowserPages(bool useDisposeAsync)
         {
             Assert.Contains(Page, await Browser.PagesAsync());
-            await Page.CloseAsync();
+            if (useDisposeAsync)
+            {
+                // emulates what would happen in a C#8 await using block
+                await Page.DisposeAsync();
+            }
+            else
+            {
+                await Page.CloseAsync();
+            }
             Assert.DoesNotContain(Page, await Browser.PagesAsync());
         }
 
@@ -103,4 +113,4 @@ public async Task ShouldCloseWhenConnectionBreaksPrematurely()
             await Page.CloseAsync();
         }
     }
-}
+}

lib/PuppeteerSharp.Tests/PuppeteerTests/PuppeteerLaunchTests.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
@@ -184,8 +184,10 @@ public void ShouldReturnTheDefaultChromeArguments()
             }));
         }
 
-        [Fact]
-        public async Task ChromeShouldBeClosed()
+        [Theory]
+        [InlineData(false)]
+        [InlineData(true)]
+        public async Task ChromeShouldBeClosed(bool useDisposeAsync)
         {
             var options = TestConstants.DefaultBrowserOptions();
             var launcher = new Launcher(TestConstants.LoggerFactory);
@@ -196,7 +198,15 @@ public async Task ChromeShouldBeClosed()
                 var response = await page.GoToAsync(TestConstants.EmptyPage);
                 Assert.Equal(HttpStatusCode.OK, response.Status);
 
-                await browser.CloseAsync();
+                if (useDisposeAsync)
+                {
+                    // emulates what would happen in a C#8 await using block
+                    await browser.DisposeAsync();
+                }
+                else
+                {
+                    await browser.CloseAsync();
+                }
 
                 Assert.True(launcher.Process.HasExited);
             }
@@ -366,4 +376,4 @@ public async Task ShouldSupportCustomTransport()
             }
         }
     }
-}
+}

lib/PuppeteerSharp/Browser.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
@@ -35,7 +35,7 @@ namespace PuppeteerSharp
     /// ]]>
     /// </code>
     /// </example>
-    public class Browser : IDisposable
+    public class Browser : IDisposable, IAsyncDisposable
     {
         /// <summary>
         /// Time in milliseconds for chromium process to exit gracefully.
@@ -537,5 +537,16 @@ internal static async Task<Browser> CreateAsync(
         public void Dispose() => _ = CloseAsync();
 
         #endregion
+
+        #region IAsyncDisposable
+
+        /// <summary>
+        /// Closes <see cref="Connection"/> and any Chromium <see cref="Process"/> that was
+        /// created by Puppeteer.
+        /// </summary>
+        /// <returns>ValueTask</returns>
+        public ValueTask DisposeAsync() => new ValueTask(CloseAsync());
+
+        #endregion
     }
 }

lib/PuppeteerSharp/Page.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
@@ -35,7 +35,7 @@ namespace PuppeteerSharp
     /// </code>
     /// </example>
     [DebuggerDisplay("Page {Url}")]
-    public class Page : IDisposable
+    public class Page : IDisposable, IAsyncDisposable
     {
         private readonly TaskQueue _screenshotTaskQueue;
         private readonly EmulationManager _emulationManager;
@@ -2430,5 +2430,17 @@ string SerializeArgument(object arg)
         /// the garbage collector can reclaim the memory that the <see cref="Page"/> was occupying.</remarks>
         public void Dispose() => CloseAsync();
         #endregion
+
+        #region IAsyncDisposable
+        /// <summary>
+        /// Releases all resource used by the <see cref="Page"/> object by calling the <see cref="CloseAsync"/> method.
+        /// </summary>
+        /// <remarks>Call <see cref="DisposeAsync"/> when you are finished using the <see cref="Page"/>. The
+        /// <see cref="DisposeAsync"/> method leaves the <see cref="Page"/> in an unusable state. After
+        /// calling <see cref="DisposeAsync"/>, you must release all references to the <see cref="Page"/> so
+        /// the garbage collector can reclaim the memory that the <see cref="Page"/> was occupying.</remarks>
+        /// <returns>ValueTask</returns>
+        public ValueTask DisposeAsync() => new ValueTask(CloseAsync());
+        #endregion
     }
 }

lib/PuppeteerSharp/PuppeteerSharp.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <PackOnBuild>true</PackOnBuild>
@@ -34,7 +34,8 @@
     <PackageReference Include="Newtonsoft.Json" Version="10.0.3" />
     <PackageReference Include="System.Net.Http" Version="4.3.3" />
     <PackageReference Include="Microsoft.AspNetCore.WebUtilities" Version="2.0.2" />
-    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.1" />
+    <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="1.1.0" />
+    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>