Bring back extension methods, fix formatting of xml doc comments (#144)

src/Microsoft.Build.Utilities.ProjectCreation.UnitTests/ExtensibilityTests.cs

@@ -11,7 +11,7 @@ namespace Microsoft.Build.Utilities.ProjectCreation.UnitTests
     public class ExtensibilityTests : MSBuildTestBase
     {
         /// <summary>
-        /// Proves that <see cref="ProjectCreator"/> can be extended by and end user through extension methods.
+        /// Proves that <see cref="ProjectCreator" /> can be extended by and end user through extension methods.
         /// </summary>
         [Fact]
         public void CustomExtensionMethod()

src/Microsoft.Build.Utilities.ProjectCreation/BuildEngine.cs

@@ -9,51 +9,51 @@
 namespace Microsoft.Build.Utilities.ProjectCreation
 {
     /// <summary>
-    /// Represents an implementation of <see cref="IBuildEngine"/> that allows for capturing logged events in tasks.
+    /// Represents an implementation of <see cref="IBuildEngine" /> that allows for capturing logged events in tasks.
     /// </summary>
     public sealed class BuildEngine : BuildEventArgsCollection, IBuildEngine
     {
         private BuildEngine()
         {
         }
 
-        /// <inheritdoc cref="IBuildEngine.ColumnNumberOfTaskNode"/>
+        /// <inheritdoc cref="IBuildEngine.ColumnNumberOfTaskNode" />
         public int ColumnNumberOfTaskNode => 0;
 
-        /// <inheritdoc cref="IBuildEngine.ContinueOnError"/>
+        /// <inheritdoc cref="IBuildEngine.ContinueOnError" />
         public bool ContinueOnError => false;
 
-        /// <inheritdoc cref="IBuildEngine.LineNumberOfTaskNode"/>
+        /// <inheritdoc cref="IBuildEngine.LineNumberOfTaskNode" />
         public int LineNumberOfTaskNode => 0;
 
-        /// <inheritdoc cref="IBuildEngine.ProjectFileOfTaskNode"/>
+        /// <inheritdoc cref="IBuildEngine.ProjectFileOfTaskNode" />
         public string? ProjectFileOfTaskNode => null;
 
         /// <summary>
-        /// Creates an instance of the <see cref="BuildEngine"/> class.
+        /// Creates an instance of the <see cref="BuildEngine" /> class.
         /// </summary>
-        /// <returns>A <see cref="BuildEngine"/> instance.</returns>
+        /// <returns>A <see cref="BuildEngine" /> instance.</returns>
         public static BuildEngine Create()
         {
             return new BuildEngine();
         }
 
-        /// <inheritdoc cref="IBuildEngine.BuildProjectFile"/>
+        /// <inheritdoc cref="IBuildEngine.BuildProjectFile" />
         public bool BuildProjectFile(string projectFileName, string[] targetNames, IDictionary globalProperties, IDictionary targetOutputs)
         {
             throw new NotSupportedException();
         }
 
-        /// <inheritdoc cref="IBuildEngine.LogCustomEvent"/>
+        /// <inheritdoc cref="IBuildEngine.LogCustomEvent" />
         public void LogCustomEvent(CustomBuildEventArgs e) => Add(e);
 
-        /// <inheritdoc cref="IBuildEngine.LogErrorEvent"/>
+        /// <inheritdoc cref="IBuildEngine.LogErrorEvent" />
         public void LogErrorEvent(BuildErrorEventArgs e) => Add(e);
 
-        /// <inheritdoc cref="IBuildEngine.LogMessageEvent"/>
+        /// <inheritdoc cref="IBuildEngine.LogMessageEvent" />
         public void LogMessageEvent(BuildMessageEventArgs e) => Add(e);
 
-        /// <inheritdoc cref="IBuildEngine.LogWarningEvent"/>
+        /// <inheritdoc cref="IBuildEngine.LogWarningEvent" />
         public void LogWarningEvent(BuildWarningEventArgs e) => Add(e);
     }
 }

src/Microsoft.Build.Utilities.ProjectCreation/BuildEventArgsCollection.cs

@@ -13,7 +13,7 @@
 namespace Microsoft.Build.Utilities.ProjectCreation
 {
     /// <summary>
-    /// Represents a collection of <see cref="BuildEventArgs"/> objects.
+    /// Represents a collection of <see cref="BuildEventArgs" /> objects.
     /// </summary>
     public abstract class BuildEventArgsCollection : IDisposable
     {
@@ -38,7 +38,7 @@ public abstract class BuildEventArgsCollection : IDisposable
         private readonly ConcurrentQueue<BuildEventArgs> _allEvents = new ConcurrentQueue<BuildEventArgs>();
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="BuildEventArgsCollection"/> class.
+        /// Initializes a new instance of the <see cref="BuildEventArgsCollection" /> class.
         /// </summary>
         protected BuildEventArgsCollection()
         {
@@ -67,7 +67,7 @@ protected BuildEventArgsCollection()
         public BuildMessageEventArgsCollection MessageEvents { get; }
 
         /// <summary>
-        /// Gets a <see cref="BuildMessageCollection"/> object that gets the messages from the build.
+        /// Gets a <see cref="BuildMessageCollection" /> object that gets the messages from the build.
         /// </summary>
         public BuildMessageCollection Messages { get; }
 
@@ -81,7 +81,7 @@ protected BuildEventArgsCollection()
         /// </summary>
         public IReadOnlyCollection<string> Warnings => _warningEvents.Select(i => i.Message).ToList();
 
-        /// <inheritdoc cref="IDisposable.Dispose"/>
+        /// <inheritdoc cref="IDisposable.Dispose" />
         public virtual void Dispose()
         {
             _errorEvents.Clear();
@@ -160,7 +160,7 @@ public string GetConsoleLog(LoggerVerbosity verbosity = LoggerVerbosity.Normal)
         /// <summary>
         /// Adds a build event.
         /// </summary>
-        /// <param name="buildEventArgs">A <see cref="BuildEventArgs"/> object to add.</param>
+        /// <param name="buildEventArgs">A <see cref="BuildEventArgs" /> object to add.</param>
         protected void Add(BuildEventArgs buildEventArgs)
         {
             _allEvents.Enqueue(buildEventArgs);

src/Microsoft.Build.Utilities.ProjectCreation/BuildMessageCollection.cs

@@ -18,39 +18,39 @@ public sealed class BuildMessageCollection : IReadOnlyCollection<string>
         private readonly BuildEventArgsCollection _buildOutput;
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="BuildMessageCollection"/> class.
+        /// Initializes a new instance of the <see cref="BuildMessageCollection" /> class.
         /// </summary>
-        /// <param name="buildOutput">The <see cref="BuildEventArgsCollection"/> object that has message events.</param>
+        /// <param name="buildOutput">The <see cref="BuildEventArgsCollection" /> object that has message events.</param>
         internal BuildMessageCollection(BuildEventArgsCollection buildOutput)
         {
             _buildOutput = buildOutput ?? throw new ArgumentNullException(nameof(buildOutput));
         }
 
-        /// <inheritdoc cref="IReadOnlyCollection{T}.Count"/>
+        /// <inheritdoc cref="IReadOnlyCollection{T}.Count" />
         public int Count => _buildOutput.MessageEvents.Count;
 
         /// <summary>
-        /// Gets the messages that were logged with <see cref="MessageImportance.High"/>.
+        /// Gets the messages that were logged with <see cref="MessageImportance.High" />.
         /// </summary>
         public IReadOnlyCollection<string> High => _buildOutput.MessageEvents.High.Select(i => i.Message).ToList();
 
         /// <summary>
-        /// Gets the messages that were logged with <see cref="MessageImportance.Low"/>.
+        /// Gets the messages that were logged with <see cref="MessageImportance.Low" />.
         /// </summary>
         public IReadOnlyCollection<string> Low => _buildOutput.MessageEvents.Low.Select(i => i.Message).ToList();
 
         /// <summary>
-        /// Gets the messages that were logged with <see cref="MessageImportance.Normal"/>.
+        /// Gets the messages that were logged with <see cref="MessageImportance.Normal" />.
         /// </summary>
         public IReadOnlyCollection<string> Normal => _buildOutput.MessageEvents.Normal.Select(i => i.Message).ToList();
 
-        /// <inheritdoc cref="IEnumerable{T}.GetEnumerator"/>
+        /// <inheritdoc cref="IEnumerable{T}.GetEnumerator" />
         public IEnumerator<string> GetEnumerator()
         {
             return _buildOutput.MessageEvents.Select(i => i.Message).ToList().GetEnumerator();
         }
 
-        /// <inheritdoc cref="IEnumerable.GetEnumerator"/>
+        /// <inheritdoc cref="IEnumerable.GetEnumerator" />
         IEnumerator IEnumerable.GetEnumerator()
         {
             return GetEnumerator();

src/Microsoft.Build.Utilities.ProjectCreation/BuildMessageEventArgsCollection.cs

@@ -11,46 +11,46 @@
 namespace Microsoft.Build.Utilities.ProjectCreation
 {
     /// <summary>
-    /// Represents the <see cref="BuildMessageEventArgs"/> that were logged.
+    /// Represents the <see cref="BuildMessageEventArgs" /> that were logged.
     /// </summary>
     public sealed class BuildMessageEventArgsCollection : IReadOnlyCollection<BuildMessageEventArgs>
     {
         private readonly IReadOnlyCollection<BuildMessageEventArgs> _messageEvents;
 
         /// <summary>
-        /// Initializes a new instance of the <see cref="BuildMessageEventArgsCollection"/> class.
+        /// Initializes a new instance of the <see cref="BuildMessageEventArgsCollection" /> class.
         /// </summary>
-        /// <param name="messageEvents">A <see cref="IReadOnlyCollection{BuildMessageEventArgs}"/> containing the logged message events.</param>
+        /// <param name="messageEvents">A <see cref="IReadOnlyCollection{BuildMessageEventArgs}" /> containing the logged message events.</param>
         internal BuildMessageEventArgsCollection(IReadOnlyCollection<BuildMessageEventArgs> messageEvents)
         {
             _messageEvents = messageEvents ?? throw new ArgumentNullException(nameof(messageEvents));
         }
 
-        /// <inheritdoc cref="IReadOnlyCollection{T}.Count"/>
+        /// <inheritdoc cref="IReadOnlyCollection{T}.Count" />
         public int Count => _messageEvents.Count;
 
         /// <summary>
-        /// Gets the <see cref="BuildMessageEventArgs"/> that were logged with <see cref="MessageImportance.High"/>.
+        /// Gets the <see cref="BuildMessageEventArgs" /> that were logged with <see cref="MessageImportance.High" />.
         /// </summary>
         public IReadOnlyCollection<BuildMessageEventArgs> High => _messageEvents.Where(i => i.Importance == MessageImportance.High).ToList();
 
         /// <summary>
-        /// Gets the <see cref="BuildMessageEventArgs"/> that were logged with <see cref="MessageImportance.Low"/>.
+        /// Gets the <see cref="BuildMessageEventArgs" /> that were logged with <see cref="MessageImportance.Low" />.
         /// </summary>
         public IReadOnlyCollection<BuildMessageEventArgs> Low => _messageEvents.Where(i => i.Importance == MessageImportance.Low).ToList();
 
         /// <summary>
-        /// Gets the <see cref="BuildMessageEventArgs"/> that were logged with <see cref="MessageImportance.Normal"/>.
+        /// Gets the <see cref="BuildMessageEventArgs" /> that were logged with <see cref="MessageImportance.Normal" />.
         /// </summary>
         public IReadOnlyCollection<BuildMessageEventArgs> Normal => _messageEvents.Where(i => i.Importance == MessageImportance.Normal).ToList();
 
-        /// <inheritdoc cref="IEnumerable{T}.GetEnumerator"/>
+        /// <inheritdoc cref="IEnumerable{T}.GetEnumerator" />
         public IEnumerator<BuildMessageEventArgs> GetEnumerator()
         {
             return _messageEvents.GetEnumerator();
         }
 
-        /// <inheritdoc cref="IEnumerable.GetEnumerator"/>
+        /// <inheritdoc cref="IEnumerable.GetEnumerator" />
         IEnumerator IEnumerable.GetEnumerator()
         {
             return GetEnumerator();

src/Microsoft.Build.Utilities.ProjectCreation/BuildOutput.cs

@@ -20,7 +20,7 @@ public sealed class BuildOutput : BuildEventArgsCollection, ILogger
         private readonly ConcurrentDictionary<string, bool> _resultsByProject = new ConcurrentDictionary<string, bool>(StringComparer.OrdinalIgnoreCase);
 
         /// <summary>
-        /// Stores the <see cref="BuildFinishedEventArgs"/> that were logged when the build finished.
+        /// Stores the <see cref="BuildFinishedEventArgs" /> that were logged when the build finished.
         /// </summary>
         private BuildFinishedEventArgs? _buildFinished;
 
@@ -29,7 +29,7 @@ private BuildOutput()
             Parameters = string.Empty;
         }
 
-        /// <inheritdoc cref="ILogger.Parameters"/>
+        /// <inheritdoc cref="ILogger.Parameters" />
         public string Parameters { get; set; }
 
         /// <summary>
@@ -42,35 +42,35 @@ private BuildOutput()
         /// </summary>
         public bool? Succeeded => _buildFinished?.Succeeded;
 
-        /// <inheritdoc cref="ILogger.Verbosity"/>
+        /// <inheritdoc cref="ILogger.Verbosity" />
         public LoggerVerbosity Verbosity { get; set; }
 
         /// <summary>
-        /// Creates an instance of the <see cref="BuildOutput"/> class.
+        /// Creates an instance of the <see cref="BuildOutput" /> class.
         /// </summary>
-        /// <returns>A <see cref="BuildOutput"/> instance.</returns>
+        /// <returns>A <see cref="BuildOutput" /> instance.</returns>
         public static BuildOutput Create()
         {
             return new BuildOutput();
         }
 
-        /// <inheritdoc cref="IDisposable.Dispose"/>
+        /// <inheritdoc cref="IDisposable.Dispose" />
         public override void Dispose()
         {
             _buildFinished = null;
 
             base.Dispose();
         }
 
-        /// <inheritdoc cref="ILogger.Initialize"/>
+        /// <inheritdoc cref="ILogger.Initialize" />
         public void Initialize(IEventSource eventSource)
         {
             eventSource.BuildFinished += OnBuildFinished;
             eventSource.ProjectFinished += OnProjectFinished;
             eventSource.AnyEventRaised += OnAnyEventRaised;
         }
 
-        /// <inheritdoc cref="ILogger.Shutdown"/>
+        /// <inheritdoc cref="ILogger.Shutdown" />
         public void Shutdown()
         {
         }

src/Microsoft.Build.Utilities.ProjectCreation/ExtensionMethods.cs

@@ -13,14 +13,14 @@ namespace Microsoft.Build.Utilities.ProjectCreation
     /// <summary>
     /// Provides extension methods.
     /// </summary>
-    internal static class ExtensionMethods
+    public static class ExtensionMethods
     {
         /// <summary>
-        /// Gets the current object as an <see cref="IEnumerable{T}"/>.
+        /// Gets the current object as an <see cref="IEnumerable{T}" />.
         /// </summary>
         /// <typeparam name="T">The type of the object.</typeparam>
-        /// <param name="item">The item to make into an <see cref="IEnumerable{T}"/>.</param>
-        /// <returns>The current object as an <see cref="IEnumerable{T}"/>.</returns>
+        /// <param name="item">The item to make into an <see cref="IEnumerable{T}" />.</param>
+        /// <returns>The current object as an <see cref="IEnumerable{T}" />.</returns>
         [DebuggerStepThrough]
         public static IEnumerable<T> AsEnumerable<T>(this T? item)
             where T : class
@@ -42,7 +42,7 @@ public static IEnumerable<T> AsEnumerable<T>(this T? item)
         /// </summary>
         /// <param name="first">The first dictionary and all of its values to start with.</param>
         /// <param name="second">The second dictionary to merge with the first and override its values.</param>
-        /// <returns>A merged <see cref="IDictionary{String,String}"/> with the values of the first dictionary overridden by the second.</returns>
+        /// <returns>A merged <see cref="IDictionary{String,String}" /> with the values of the first dictionary overridden by the second.</returns>
         [DebuggerStepThrough]
         public static IDictionary<string, string?> Merge(this IDictionary<string, string?>? first, IDictionary<string, string?> second)
         {
@@ -54,8 +54,8 @@ public static IEnumerable<T> AsEnumerable<T>(this T? item)
         /// </summary>
         /// <param name="first">The first dictionary and all of its values to start with.</param>
         /// <param name="second">The second dictionary to merge with the first and override its values.</param>
-        /// <param name="comparer">The <see cref="IEqualityComparer{String}"/> implementation to use when comparing keys, or null to use the default <see cref="IEqualityComparer{String}"/> for the type of the key. </param>
-        /// <returns>A merged <see cref="IDictionary{String,String}"/> with the values of the first dictionary overridden by the second.</returns>
+        /// <param name="comparer">The <see cref="IEqualityComparer{String}" /> implementation to use when comparing keys, or null to use the default <see cref="IEqualityComparer{String}" /> for the type of the key. </param>
+        /// <returns>A merged <see cref="IDictionary{String,String}" /> with the values of the first dictionary overridden by the second.</returns>
         [DebuggerStepThrough]
         public static IDictionary<string, string?> Merge(this IDictionary<string, string?>? first, IDictionary<string, string?> second, IEqualityComparer<string> comparer)
         {
@@ -93,7 +93,8 @@ public static T[] ToArrayWithSingleElement<T>(this T item)
         /// <param name="packageTypes">An <see cref="IEnumerable{String}" /> containing package types.</param>
         /// <returns>An <see cref="IEnumerable{PackageType}" /> containing the package types.</returns>
         /// <exception cref="ArgumentOutOfRangeException">Any package types are invalid.</exception>
-        public static IEnumerable<PackageType> ToPackageTypes(this IEnumerable<string>? packageTypes)
+        [DebuggerStepThrough]
+        internal static IEnumerable<PackageType> ToPackageTypes(this IEnumerable<string>? packageTypes)
         {
             if (packageTypes == null)
             {

src/Microsoft.Build.Utilities.ProjectCreation/MSBuildAssemblyResolver.netcoreapp3.1.cs

@@ -14,7 +14,7 @@ namespace Microsoft.Build.Utilities.ProjectCreation
     public static partial class MSBuildAssemblyResolver
     {
         /// <summary>
-        /// A <see cref="ResolveEventHandler"/> for MSBuild related assemblies.
+        /// A <see cref="ResolveEventHandler" /> for MSBuild related assemblies.
         /// </summary>
         /// <param name="sender">The source of the event.</param>
         /// <param name="args">The event data.</param>

src/Microsoft.Build.Utilities.ProjectCreation/MSBuildAssemblyResolver.netframework.cs

@@ -67,7 +67,7 @@ public static partial class MSBuildAssemblyResolver
         private static readonly char[] PathSplitChars = { Path.PathSeparator };
 
         /// <summary>
-        /// A <see cref="ResolveEventHandler"/> for MSBuild related assemblies.
+        /// A <see cref="ResolveEventHandler" /> for MSBuild related assemblies.
         /// </summary>
         /// <param name="sender">The source of the event.</param>
         /// <param name="args">The event data.</param>

src/Microsoft.Build.Utilities.ProjectCreation/PackageFeed.Items.cs

@@ -15,10 +15,10 @@ public partial class ProjectCreator
         /// <param name="includeAssets">An optional value specifying which assets belonging to the package should be consumed.</param>
         /// <param name="excludeAssets">An optional value specifying which assets belonging to the package should be not consumed.</param>
         /// <param name="privateAssets">An optional value specifying which assets belonging to the package should not flow to dependent projects.</param>
-        /// <param name="metadata">An optional <see cref="IDictionary{String,String}"/> containing metadata for the item.</param>
+        /// <param name="metadata">An optional <see cref="IDictionary{String,String}" /> containing metadata for the item.</param>
         /// <param name="condition">An optional condition to add to the item.</param>
         /// <param name="label">An optional label to add to the item.</param>
-        /// <returns>The current <see cref="ProjectCreator"/>.</returns>
+        /// <returns>The current <see cref="ProjectCreator" />.</returns>
         public ProjectCreator ItemPackageReference(Package package, string? includeAssets = null, string? excludeAssets = null, string? privateAssets = null, IDictionary<string, string?>? metadata = null, string? condition = null, string? label = null)
         {
             return ItemPackageReference(package.Id, package.Version, includeAssets, excludeAssets, privateAssets, metadata, condition, label);