From 2c4c35e126d9287053cdaa772a5f9ca307650f7c Mon Sep 17 00:00:00 2001
From: "N. Taylor Mullen" <nimullen@microsoft.com>
Date: Mon, 13 Apr 2015 14:52:06 -0700
Subject: [PATCH] Add rendering logic for PreElement and PostElement on
 TagHelperOutput.

- Added unit tests to validate that the properties were rendered correctly.
- Modified functional tests to utilize PreElement and PostElement.

aspnet/Razor#341
---
 src/Microsoft.AspNet.Mvc.Razor/RazorPage.cs   |   4 +
 .../TagHelpersWebSite.Home.Index.html         |   4 +-
 .../RazorPageTest.cs                          | 362 ++++++++++++++++--
 .../TagHelpers/SurroundTagHelper.cs           |  30 ++
 .../TagHelpersWebSite/Views/Home/Index.cshtml |   6 +-
 5 files changed, 362 insertions(+), 44 deletions(-)
 create mode 100644 test/WebSites/TagHelpersWebSite/TagHelpers/SurroundTagHelper.cs

diff --git a/src/Microsoft.AspNet.Mvc.Razor/RazorPage.cs b/src/Microsoft.AspNet.Mvc.Razor/RazorPage.cs
index 5e33869980..6fbb8185fd 100644
--- a/src/Microsoft.AspNet.Mvc.Razor/RazorPage.cs
+++ b/src/Microsoft.AspNet.Mvc.Razor/RazorPage.cs
@@ -278,6 +278,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             var tagHelperOutput = tagHelperExecutionContext.Output;
             var isTagNameNullOrWhitespace = string.IsNullOrWhiteSpace(tagHelperOutput.TagName);
 
+            WriteTagHelperContentTo(writer, tagHelperOutput.PreElement);
+
             if (!isTagNameNullOrWhitespace)
             {
                 writer.Write('<');
@@ -324,6 +326,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             {
                 writer.Write(string.Format(CultureInfo.InvariantCulture, "</{0}>", tagHelperOutput.TagName));
             }
+
+            WriteTagHelperContentTo(writer, tagHelperOutput.PostElement);
         }
 
         private void WriteTagHelperContentTo(TextWriter writer, TagHelperContent content)
diff --git a/test/Microsoft.AspNet.Mvc.FunctionalTests/compiler/resources/TagHelpersWebSite.Home.Index.html b/test/Microsoft.AspNet.Mvc.FunctionalTests/compiler/resources/TagHelpersWebSite.Home.Index.html
index 7e3acce114..bf3bb5485f 100644
--- a/test/Microsoft.AspNet.Mvc.FunctionalTests/compiler/resources/TagHelpersWebSite.Home.Index.html
+++ b/test/Microsoft.AspNet.Mvc.FunctionalTests/compiler/resources/TagHelpersWebSite.Home.Index.html
@@ -28,12 +28,12 @@
 
 
 <div>
-    <p>This website has <strong style="font-size: 1.25em;text-decoration: underline;">not</strong> been approved yet. Visit <strong><a target="_blank" href="http://www.contoso.com">www.contoso.com</a></strong> for <strong>more</strong> information.</p>
+    <p>This website has <em><strong style="font-size: 1.25em;text-decoration: underline;">not</strong></em> been approved yet. Visit <strong><a target="_blank" href="http://www.contoso.com">www.contoso.com</a></strong> for <strong>more</strong> information.</p>
 </div>
 
 <div>
     <h3 style="font-family: cursive;">Current Tag Cloud from Tag Helper</h3>
-    <section>["Lorem","ipsum","dolor","sit","amet","consectetur","adipisicing","elit","sed","do","eiusmod","tempor","incididunt","ut","labore","et","dolore","magna","aliquaUt","enim"]</section>
+    <div>["Lorem","ipsum","dolor","sit","amet","consectetur","adipisicing","elit","sed","do","eiusmod","tempor","incididunt","ut","labore","et","dolore","magna","aliquaUt","enim"]</div>
     <h3 style="font-family: cursive;">Current Tag Cloud from ViewComponentHelper:</h3>
     <section>["Lorem","ipsum","dolor","sit","amet","consectetur","adipisicing","elit","sed","do","eiusmod","tempor","incididunt","ut","labore"]</section>
 </div>
diff --git a/test/Microsoft.AspNet.Mvc.Razor.Test/RazorPageTest.cs b/test/Microsoft.AspNet.Mvc.Razor.Test/RazorPageTest.cs
index c9fef69fe2..25c2000076 100644
--- a/test/Microsoft.AspNet.Mvc.Razor.Test/RazorPageTest.cs
+++ b/test/Microsoft.AspNet.Mvc.Razor.Test/RazorPageTest.cs
@@ -722,85 +722,365 @@ namespace Microsoft.AspNet.Mvc.Razor
                 {
                     {
                         // parameters: TagName, Attributes, SelfClosing, PreContent, Content, PostContent
-                        GetTagHelperOutput("div", new Dictionary<string, object>(), false, null, "Hello World!", null),
+                        GetTagHelperOutput(
+                            tagName:     "div",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<div>Hello World!</div>"
                     },
                     {
-                        GetTagHelperOutput(null, new Dictionary<string, object>(), false, null, "Hello World!", null),
-                        "Hello World!"
-                    },
-                    {
-                        GetTagHelperOutput("  ", new Dictionary<string, object>(), false, null, "Hello World!", null),
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "Hello World!"
                     },
                     {
                         GetTagHelperOutput(
-                            "p",
-                            new Dictionary<string, object>() { { "test", "testVal" } },
-                            false,
-                            null,
-                            "Hello World!",
-                            null),
+                            tagName:     "  ",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
+                        "Hello World!"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>() { { "test", "testVal" } },
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<p test=\"testVal\">Hello World!</p>"
                     },
                     {
                         GetTagHelperOutput(
-                            "p",
-                            new Dictionary<string, object>() { { "test", "testVal" }, { "something", "  spaced  " } },
-                            false,
-                            null,
-                            "Hello World!",
-                            null),
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>() { { "test", "testVal" }, { "something", "  spaced  " } },
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<p test=\"testVal\" something=\"  spaced  \">Hello World!</p>"
                     },
                     {
                         GetTagHelperOutput(
-                            "p",
-                            new Dictionary<string, object>() { { "test", "testVal" } },
-                            true,
-                            null,
-                            "Hello World!",
-                            null),
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>() { { "test", "testVal" } },
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<p test=\"testVal\" />"
                     },
                     {
                         GetTagHelperOutput(
-                            "p",
-                            new Dictionary<string, object>() { { "test", "testVal" }, { "something", "  spaced  " } },
-                            true,
-                            null,
-                            "Hello World!",
-                            null),
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>() { { "test", "testVal" }, { "something", "  spaced  " } },
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<p test=\"testVal\" something=\"  spaced  \" />"
                     },
                     {
-                        GetTagHelperOutput("p", new Dictionary<string, object>(), false, "Hello World!", null, null),
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  "Hello World!",
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
                         "<p>Hello World!</p>"
                     },
                     {
-                        GetTagHelperOutput("p", new Dictionary<string, object>(), false, null, "Hello World!", null),
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     "Hello World!",
+                            postContent: null,
+                            postElement: null),
                         "<p>Hello World!</p>"
                     },
                     {
-                        GetTagHelperOutput("p", new Dictionary<string, object>(), false, null, null, "Hello World!"),
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: "Hello World!",
+                            postElement: null),
                         "<p>Hello World!</p>"
                     },
                     {
-                        GetTagHelperOutput("p", new Dictionary<string, object>(), false, "Hello", "Test", "World!"),
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: null),
                         "<p>HelloTestWorld!</p>"
                     },
                     {
-                        GetTagHelperOutput("p", new Dictionary<string, object>(), true, "Hello", "Test", "World!"),
+                        GetTagHelperOutput(
+                            tagName:     "p",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: null),
                         "<p />"
                     },
                     {
-                        GetTagHelperOutput("custom", new Dictionary<string, object>(), false, "Hello", "Test", "World!"),
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: null),
                         "<custom>HelloTestWorld!</custom>"
                     },
                     {
-                        GetTagHelperOutput("random", new Dictionary<string, object>(), true, "Hello", "Test", "World!"),
+                        GetTagHelperOutput(
+                            tagName:     "random",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: null),
                         "<random />"
-                    }
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
+                        "Before<custom></custom>"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
+                        "Before"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: true,
+                            preElement:  "Before",
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
+                        "Before"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: true,
+                            preElement:  "Before",
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
+                        "Before<custom test=\"testVal\" />"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  "Before",
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: null),
+                        "Before<custom />"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: "After"),
+                        "<custom></custom>After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: "After"),
+                        "After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: "After"),
+                        "After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: "After"),
+                        "<custom test=\"testVal\" />After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  null,
+                            preContent:  null,
+                            content:     null,
+                            postContent: null,
+                            postElement: "After"),
+                        "<custom />After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "Before<custom>HelloTestWorld!</custom>After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "Before<custom test=\"testVal\">HelloTestWorld!</custom>After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     "custom",
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "Before<custom />After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: true,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "BeforeHelloTestWorld!After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object>(),
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "BeforeHelloTestWorld!After"
+                    },
+                    {
+                        GetTagHelperOutput(
+                            tagName:     null,
+                            attributes:  new Dictionary<string, object> { { "test", "testVal" } },
+                            selfClosing: false,
+                            preElement:  "Before",
+                            preContent:  "Hello",
+                            content:     "Test",
+                            postContent: "World!",
+                            postElement: "After"),
+                        "BeforeHelloTestWorld!After"
+                    },
                 };
             }
         }
@@ -937,18 +1217,22 @@ namespace Microsoft.AspNet.Mvc.Razor
             string tagName,
             IDictionary<string, object> attributes,
             bool selfClosing,
+            string preElement,
             string preContent,
             string content,
-            string postContent)
+            string postContent,
+            string postElement)
         {
             var output = new TagHelperOutput(tagName, attributes)
             {
                 SelfClosing = selfClosing
             };
 
+            output.PreElement.SetContent(preElement);
             output.PreContent.SetContent(preContent);
             output.Content.SetContent(content);
             output.PostContent.SetContent(postContent);
+            output.PostElement.SetContent(postElement);
 
             return output;
         }
diff --git a/test/WebSites/TagHelpersWebSite/TagHelpers/SurroundTagHelper.cs b/test/WebSites/TagHelpersWebSite/TagHelpers/SurroundTagHelper.cs
new file mode 100644
index 0000000000..e8e3f26e0d
--- /dev/null
+++ b/test/WebSites/TagHelpersWebSite/TagHelpers/SurroundTagHelper.cs
@@ -0,0 +1,30 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Razor.Runtime.TagHelpers;
+
+namespace TagHelpersWebSite.TagHelpers
+{
+    [TargetElement(Attributes = nameof(Surround))]
+    public class SurroundTagHelper : TagHelper
+    {
+        public override int Order
+        {
+            get
+            {
+                // Run first
+                return int.MinValue;
+            }
+        }
+
+        public string Surround { get; set; }
+
+        public override void Process(TagHelperContext context, TagHelperOutput output)
+        {
+            var surroundingTagName = Surround.ToLowerInvariant();
+
+            output.PreElement.SetContent($"<{surroundingTagName}>");
+            output.PostElement.SetContent($"</{surroundingTagName}>");
+        }
+    }
+}
\ No newline at end of file
diff --git a/test/WebSites/TagHelpersWebSite/Views/Home/Index.cshtml b/test/WebSites/TagHelpersWebSite/Views/Home/Index.cshtml
index 2be5cdc0e0..79fec8959f 100644
--- a/test/WebSites/TagHelpersWebSite/Views/Home/Index.cshtml
+++ b/test/WebSites/TagHelpersWebSite/Views/Home/Index.cshtml
@@ -17,16 +17,16 @@
 }
 
 <div condition="!Model.Approved">
-    <p>This website has <strong>not</strong> been approved yet. Visit www.contoso.com for <strong make-pretty="false">more</strong> information.</p>
+    <p>This website has <strong surround="em">not</strong> been approved yet. Visit www.contoso.com for <strong make-pretty="false">more</strong> information.</p>
 </div>
 
 <div>
     <h3>Current Tag Cloud from Tag Helper</h3>
-    <section><tag-cloud count="Model.TagsToShow" /></section>
+    <tag-cloud count="Model.TagsToShow" surround="div" />
     <h3>Current Tag Cloud from ViewComponentHelper:</h3>
     <section>@await Component.InvokeAsync("Tags", 15)</section>
 </div>
 
 @section footerContent {
-    <p condition="Model.Approved">&copy; @Model.CopyrightYear - My ASP.NET Application</p>
+    <p condition="Model.Approved" surround="section">&copy; @Model.CopyrightYear - My ASP.NET Application</p>
 }
\ No newline at end of file