Add XML Doc snippet support

eng/SnippetGenerator/CSharpProcessor.cs

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using System.Linq;
+using System.Text.RegularExpressions;
+
+namespace SnippetGenerator
+{
+    public class CSharpProcessor
+    {
+        private static readonly string _snippetFormat = "{3}<code snippet=\"{0}\">{1}{2}</code>";
+        private static readonly Regex _snippetRegex = new Regex("^(?<ident>\\s*)\\/{3}\\s*<code snippet=\\\"(?<name>[\\w:]+)\\\">.*?\\/{3}\\s*<\\/code>",
+            RegexOptions.Compiled | RegexOptions.Multiline | RegexOptions.Singleline | RegexOptions.IgnoreCase);
+
+        public static string Process(string markdown, Func<string, string> snippetProvider)
+        {
+            return _snippetRegex.Replace(markdown, match =>
+            {
+                var name = match.Groups["name"].Value;
+                var prefix = match.Groups["ident"].Value + "/// ";
+
+                var snippetText = snippetProvider(name);
+                var text =
+                    string.Join(Environment.NewLine,
+                        snippetText.Split(Environment.NewLine).Select(l=>prefix + l));
+
+                return string.Format(_snippetFormat, name, Environment.NewLine, text, prefix);
+            });
+        }
+
+    }
+}

eng/SnippetGenerator/DirectoryProcessor.cs

@@ -37,35 +37,50 @@ public DirectoryProcessor(string directory)
 
         public void Process()
         {
-            foreach (var mdFile in Directory.EnumerateFiles(_directory, "*.md", SearchOption.AllDirectories))
-            {
-                Console.WriteLine($"Processing {mdFile}");
 
-                var text = File.ReadAllText(mdFile);
-                bool changed = false;
+            List<string> files = new List<string>();
+            files.AddRange(Directory.EnumerateFiles(_directory, "*.md", SearchOption.AllDirectories));
+            files.AddRange(Directory.EnumerateFiles(_directory, "*.cs", SearchOption.AllDirectories));
 
-                text = MarkdownProcessor.Process(text, s =>
+            foreach (var file in files)
+            {
+                string SnippetProvider(string s)
                 {
                     var selectedSnippets = _snippets.Value.Where(snip => snip.Name == s).ToArray();
                     if (selectedSnippets.Length > 1)
                     {
                         throw new InvalidOperationException($"Multiple snippets with the name '{s}' defined '{_directory}'");
                     }
+
                     if (selectedSnippets.Length == 0)
                     {
                         throw new InvalidOperationException($"Snippet '{s}' not found in directory '{_directory}'");
                     }
 
                     var selectedSnippet = selectedSnippets.Single();
-                    Console.WriteLine($"Replaced {selectedSnippet.Name}");
-                    changed = true;
+                    Console.WriteLine($"Replaced {selectedSnippet.Name} in {file}");
                     return FormatSnippet(selectedSnippet.Text);
-                });
+                }
+
+                var originalText = File.ReadAllText(file);
+
+                string text;
+                switch (Path.GetExtension(file))
+                {
+                    case ".md":
+                        text = MarkdownProcessor.Process(originalText, SnippetProvider);
+                        break;
+                    case ".cs":
+                        text = CSharpProcessor.Process(originalText, SnippetProvider);
+                        break;
+                    default:
+                        throw new NotSupportedException(file);
+                }
 
-                if (changed)
+                if (text != originalText)
                 {
                     _utf8EncodingWithoutBOM = new UTF8Encoding(false);
-                    File.WriteAllText(mdFile, text, _utf8EncodingWithoutBOM);
+                    File.WriteAllText(file, text, _utf8EncodingWithoutBOM);
                 }
             }
         }

sdk/core/Azure.Core/src/AsyncPageable.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
+// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
 using System.Collections.Generic;
@@ -13,6 +13,37 @@ namespace Azure
     /// iterate over.
     /// </summary>
     /// <typeparam name="T">The type of the values.</typeparam>
+    /// <example>
+    /// Example of enumerating an AsyncPageable using the <c> async foreach </c> loop:
+    /// <code snippet="Snippet:AsyncPageable">
+    /// // call a service method, which returns AsyncPageable<T>
+    /// AsyncPageable<SecretProperties> allSecretProperties = client.GetPropertiesOfSecretsAsync();
+    /// 
+    /// await foreach (SecretProperties secretProperties in allSecretProperties)
+    /// {
+    ///     Console.WriteLine(secretProperties.Name);
+    /// }
+    /// </code>
+    /// or using a while loop:
+    /// <code snippet="Snippet:AsyncPageableLoop">
+    /// // call a service method, which returns AsyncPageable<T>
+    /// AsyncPageable<SecretProperties> allSecretProperties = client.GetPropertiesOfSecretsAsync();
+    /// 
+    /// IAsyncEnumerator<SecretProperties> enumerator = allSecretProperties.GetAsyncEnumerator();
+    /// try
+    /// {
+    ///     while (await enumerator.MoveNextAsync())
+    ///     {
+    ///         SecretProperties secretProperties = enumerator.Current;
+    ///         Console.WriteLine(secretProperties.Name);
+    ///     }
+    /// }
+    /// finally
+    /// {
+    ///     await enumerator.DisposeAsync();
+    /// }
+    /// </code>
+    /// </example>
     public abstract class AsyncPageable<T> : IAsyncEnumerable<T> where T : notnull
     {
         /// <summary>