From 1b28e191140ab85270160401db1333a279cd8db5 Mon Sep 17 00:00:00 2001
From: Doug Bunting <dougbu@microsoft.com>
Date: Mon, 17 Nov 2014 08:50:27 -0800
Subject: [PATCH] MVC tag helpers should not override tag name in Razor source
 - #1523 - remove `TagHelperOutput.Merge()` extension method entirely - test
 tag name preservation with all MVC tag helpers  - `<input/>` tag helper
 generation of a checkbox wasn't previously tested

nits:
- fix argument order in a couple of `Assert.Equal()` calls
- remove use of "original tag name"
---
 .../FormTagHelper.cs                          |  5 ++--
 .../InputTagHelper.cs                         |  3 +-
 .../LabelTagHelper.cs                         |  2 --
 .../SelectTagHelper.cs                        |  3 +-
 .../TagHelperOutputExtensions.cs              | 17 -----------
 .../TextAreaTagHelper.cs                      |  1 -
 .../AnchorTagHelperTest.cs                    |  5 ++--
 .../FormTagHelperTest.cs                      |  5 ++--
 .../InputTagHelperTest.cs                     |  6 ++--
 .../LabelTagHelperTest.cs                     |  6 ++--
 .../OptionTagHelperTest.cs                    |  4 +--
 .../SelectTagHelperTest.cs                    | 24 +++++++--------
 .../TagHelperOutputExtensionsTest.cs          | 29 -------------------
 .../TextAreaTagHelperTest.cs                  |  6 ++--
 .../ValidationMessageTagHelperTest.cs         |  7 +++--
 .../ValidationSummaryTagHelperTest.cs         |  7 +++--
 16 files changed, 43 insertions(+), 87 deletions(-)

diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/FormTagHelper.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/FormTagHelper.cs
index 611b2a42cd..4d569cf620 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/FormTagHelper.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/FormTagHelper.cs
@@ -97,8 +97,9 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
 
                 if (tagBuilder != null)
                 {
-                    // We don't want to do a full merge because we want the TagHelper content to take precedence.
-                    output.Merge(tagBuilder);
+                    output.MergeAttributes(tagBuilder);
+                    output.Content += tagBuilder.InnerHtml;
+                    output.SelfClosing = false;
                 }
             }
 
diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/InputTagHelper.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/InputTagHelper.cs
index 0255cf9d1f..08dd948650 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/InputTagHelper.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/InputTagHelper.cs
@@ -199,8 +199,9 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 {
                     // This TagBuilder contains the one <input/> element of interest. Since this is not the "checkbox"
                     // special-case, output is a self-closing element and can merge the TagBuilder in directly.
+                    output.MergeAttributes(tagBuilder);
+                    output.Content += tagBuilder.InnerHtml;
                     output.SelfClosing = true;
-                    output.Merge(tagBuilder);
                 }
             }
         }
diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/LabelTagHelper.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/LabelTagHelper.cs
index 33cc3f047a..1f78745ff2 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/LabelTagHelper.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/LabelTagHelper.cs
@@ -48,8 +48,6 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                     {
                         output.Content = tagBuilder.InnerHtml;
                     }
-
-                    output.TagName = tagBuilder.TagName;
                 }
             }
         }
diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/SelectTagHelper.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/SelectTagHelper.cs
index d3ecbd7034..e197713458 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/SelectTagHelper.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/SelectTagHelper.cs
@@ -137,8 +137,9 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
 
                 if (tagBuilder != null)
                 {
+                    output.MergeAttributes(tagBuilder);
+                    output.Content += tagBuilder.InnerHtml;
                     output.SelfClosing = false;
-                    output.Merge(tagBuilder);
                 }
 
                 // Whether or not (not being highly unlikely) we generate anything, could update contained <option/>
diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/TagHelperOutputExtensions.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/TagHelperOutputExtensions.cs
index 4c6e2baa85..639680b493 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/TagHelperOutputExtensions.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/TagHelperOutputExtensions.cs
@@ -60,23 +60,6 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             return prefixedAttributes;
         }
 
-        /// <summary>
-        /// Merges the given <paramref name="tagBuilder"/> into the <paramref name="tagHelperOutput"/>.
-        /// </summary>
-        /// <param name="tagHelperOutput">The <see cref="TagHelperOutput"/> this method extends.</param>
-        /// <param name="tagBuilder">The <see cref="TagBuilder"/> to merge.</param>
-        /// <remarks><paramref name="tagHelperOutput"/>'s <see cref="TagHelperOutput.Content"/> has the given
-        /// <paramref name="tagBuilder"/>s <see cref="TagBuilder.InnerHtml"/> appended to it. This is to ensure
-        /// multiple <see cref="ITagHelper"/>s running on the same HTML tag don't overwrite each other; therefore,
-        /// this method may not be appropriate for all <see cref="ITagHelper"/> scenarios.</remarks>
-        public static void Merge(this TagHelperOutput tagHelperOutput, TagBuilder tagBuilder)
-        {
-            tagHelperOutput.TagName = tagBuilder.TagName;
-            tagHelperOutput.Content += tagBuilder.InnerHtml;
-
-            MergeAttributes(tagHelperOutput, tagBuilder);
-        }
-
         /// <summary>
         /// Merges the given <paramref name="tagBuilder"/>'s <see cref="TagBuilder.Attributes"/> into the 
         /// <paramref name="tagHelperOutput"/>.
diff --git a/src/Microsoft.AspNet.Mvc.TagHelpers/TextAreaTagHelper.cs b/src/Microsoft.AspNet.Mvc.TagHelpers/TextAreaTagHelper.cs
index 10d6b05c99..586a9ed3a4 100644
--- a/src/Microsoft.AspNet.Mvc.TagHelpers/TextAreaTagHelper.cs
+++ b/src/Microsoft.AspNet.Mvc.TagHelpers/TextAreaTagHelper.cs
@@ -47,7 +47,6 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
 
                     output.MergeAttributes(tagBuilder);
                     output.SelfClosing = false;
-                    output.TagName = tagBuilder.TagName;
                 }
             }
         }
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/AnchorTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/AnchorTagHelperTest.cs
index 00661226c3..b3050403c6 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/AnchorTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/AnchorTagHelperTest.cs
@@ -18,6 +18,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
         public async Task ProcessAsync_GeneratesExpectedOutput()
         {
             // Arrange
+            var expectedTagName = "not-a";
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var anchorTagHelper = new AnchorTagHelper
             {
@@ -40,7 +41,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                     { "protocol", "http" }
                 });
             var output = new TagHelperOutput(
-                "a",
+                expectedTagName,
                 attributes: new Dictionary<string, string>
                 {
                     { "id", "myanchor" },
@@ -75,7 +76,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             attribute = Assert.Single(output.Attributes, kvp => kvp.Key.Equals("href"));
             Assert.Equal("home/index", attribute.Value);
             Assert.Equal("Something", output.Content);
-            Assert.Equal("a", output.TagName);
+            Assert.Equal(expectedTagName, output.TagName);
         }
 
         [Fact]
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/FormTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/FormTagHelperTest.cs
index dda8c99644..ca5aac1902 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/FormTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/FormTagHelperTest.cs
@@ -21,6 +21,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
         public async Task ProcessAsync_GeneratesExpectedOutput()
         {
             // Arrange
+            var expectedTagName = "not-form";
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var formTagHelper = new FormTagHelper
             {
@@ -40,7 +41,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                     { "anti-forgery", true }
                 });
             var output = new TagHelperOutput(
-                "form",
+                expectedTagName,
                 attributes: new Dictionary<string, string>
                 {
                     { "id", "myform" },
@@ -78,7 +79,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             attribute = Assert.Single(output.Attributes, kvp => kvp.Key.Equals("action"));
             Assert.Equal("home/index", attribute.Value);
             Assert.Equal(expectedContent, output.Content);
-            Assert.Equal("form", output.TagName);
+            Assert.Equal(expectedTagName, output.TagName);
         }
 
         [Theory]
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/InputTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/InputTagHelperTest.cs
index c0366d1299..674ceb6e33 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/InputTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/InputTagHelperTest.cs
@@ -91,7 +91,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "value", expectedValue },
             };
             var expectedContent = "original content";
-            var expectedTagName = "input";
+            var expectedTagName = "not-input";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
 
@@ -104,7 +104,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             {
                 { "class", "form-control" },
             };
-            var output = new TagHelperOutput("original tag name", htmlAttributes, expectedContent)
+            var output = new TagHelperOutput(expectedTagName, htmlAttributes, expectedContent)
             {
                 SelfClosing = false,
             };
@@ -145,7 +145,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "value", "2014-10-15T23:24:19.000-7:00" },
             };
             var expectedContent = "original content";
-            var expectedTagName = "original tag name";
+            var expectedTagName = "input";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var metadata = metadataProvider.GetMetadataForProperty(
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/LabelTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/LabelTagHelperTest.cs
index 4dab736b23..e631a2ad11 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/LabelTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/LabelTagHelperTest.cs
@@ -97,6 +97,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             TagHelperOutputContent tagHelperOutputContent)
         {
             // Arrange
+            var expectedTagName = "not-label";
             var expectedAttributes = new Dictionary<string, string>
             {
                 { "class", "form-control" },
@@ -117,8 +118,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             {
                 { "class", "form-control" },
             };
-            var output = new TagHelperOutput("A random tag name", htmlAttributes, tagHelperOutputContent.OriginalContent);
-            var expectedTagName = "label";
+            var output = new TagHelperOutput(expectedTagName, htmlAttributes, tagHelperOutputContent.OriginalContent);
             var htmlGenerator = new TestableHtmlGenerator(metadataProvider);
             var viewContext = TestableHtmlGenerator.GetViewContext(model, htmlGenerator, metadataProvider);
             tagHelper.ViewContext = viewContext;
@@ -143,7 +143,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "class", "form-control" },
             };
             var expectedContent = "original content";
-            var expectedTagName = "original tag name";
+            var expectedTagName = "label";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var metadata = metadataProvider.GetMetadataForProperty(
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/OptionTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/OptionTagHelperTest.cs
index a4a13790e5..00c31f95b0 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/OptionTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/OptionTagHelperTest.cs
@@ -128,7 +128,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             {
                 { "label", "my-label" },
             };
-            var originalTagName = "not-option";
+            var expectedTagName = "not-option";
 
             var contextAttributes = new Dictionary<string, object>
             {
@@ -137,7 +137,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "value", value },
             };
             var tagHelperContext = new TagHelperContext(contextAttributes);
-            var output = new TagHelperOutput(originalTagName, originalAttributes, originalContent)
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, originalContent)
             {
                 SelfClosing = false,
             };
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/SelectTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/SelectTagHelperTest.cs
index da26800d39..5ca9ad1e68 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/SelectTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/SelectTagHelperTest.cs
@@ -167,7 +167,6 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "class", "form-control" },
             };
             var originalContent = "original content";
-            var originalTagName = "not-select";
 
             var expectedAttributes = new Dictionary<string, string>(originalAttributes)
             {
@@ -176,7 +175,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "valid", "from validation attributes" },
             };
             var expectedContent = originalContent;
-            var expectedTagName = "select";
+            var expectedTagName = "not-select";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
 
@@ -185,7 +184,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var modelExpression = new ModelExpression(nameAndId.Name, metadata);
 
             var tagHelperContext = new TagHelperContext(new Dictionary<string, object>());
-            var output = new TagHelperOutput(originalTagName, originalAttributes, expectedContent)
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, expectedContent)
             {
                 SelfClosing = true,
             };
@@ -238,7 +237,6 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "class", "form-control" },
             };
             var originalContent = "original content";
-            var originalTagName = "not-select";
 
             var expectedAttributes = new Dictionary<string, string>(originalAttributes)
             {
@@ -256,7 +254,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var modelExpression = new ModelExpression(nameAndId.Name, metadata);
 
             var tagHelperContext = new TagHelperContext(new Dictionary<string, object>());
-            var output = new TagHelperOutput(originalTagName, originalAttributes, originalContent)
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, originalContent)
             {
                 SelfClosing = true,
             };
@@ -313,10 +311,10 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var originalAttributes = new Dictionary<string, string>();
             var content = "original content";
             var propertyName = "Property1";
-            var tagName = "not-select";
+            var expectedTagName = "select";
 
             var tagHelperContext = new TagHelperContext(contextAttributes);
-            var output = new TagHelperOutput(tagName, originalAttributes, content);
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, content);
 
             // TODO: In real (model => model) scenario, ModelExpression should have name "" and
             // TemplateInfo.HtmlFieldPrefix should be "Property1" but empty ModelExpression name is not currently
@@ -376,7 +374,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var originalAttributes = new Dictionary<string, string>();
             var content = "original content";
             var propertyName = "Property1";
-            var tagName = "not-select";
+            var tagName = "select";
 
             var tagHelperContext = new TagHelperContext(contextAttributes);
             var output = new TagHelperOutput(tagName, originalAttributes, content);
@@ -440,7 +438,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var expectedAttributes = new Dictionary<string, string>(originalAttributes);
             expectedAttributes[attributeName] = (string)contextAttributes[attributeName];
             var expectedContent = "original content";
-            var expectedTagName = "not-select";
+            var expectedTagName = "select";
 
             var tagHelperContext = new TagHelperContext(contextAttributes);
             var output = new TagHelperOutput(expectedTagName, originalAttributes, expectedContent)
@@ -470,11 +468,11 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var contextAttributes = new Dictionary<string, object>();
             var originalAttributes = new Dictionary<string, string>();
             var content = "original content";
-            var tagName = "not-select";
+            var expectedTagName = "select";
             var expectedMessage = "Cannot determine body for <select>. 'items' must be null if 'for' is null.";
 
             var tagHelperContext = new TagHelperContext(contextAttributes);
-            var output = new TagHelperOutput(tagName, originalAttributes, content);
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, content);
             var tagHelper = new SelectTagHelper
             {
                 Items = Enumerable.Empty<SelectListItem>(),
@@ -500,12 +498,12 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             var contextAttributes = new Dictionary<string, object>();
             var originalAttributes = new Dictionary<string, string>();
             var content = "original content";
-            var tagName = "not-select";
+            var expectedTagName = "select";
             var expectedMessage = "Cannot parse 'multiple' value '" + multiple +
                 "' for <select>. Acceptable values are 'false', 'true' and 'multiple'.";
 
             var tagHelperContext = new TagHelperContext(contextAttributes);
-            var output = new TagHelperOutput(tagName, originalAttributes, content);
+            var output = new TagHelperOutput(expectedTagName, originalAttributes, content);
 
             var metadataProvider = new EmptyModelMetadataProvider();
             string model = null;
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TagHelperOutputExtensionsTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TagHelperOutputExtensionsTest.cs
index 8a394afaa8..09930340b9 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TagHelperOutputExtensionsTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TagHelperOutputExtensionsTest.cs
@@ -275,34 +275,5 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             attribute = Assert.Single(tagHelperOutput.Attributes, kvp => kvp.Key.Equals("for"));
             Assert.Equal(expectedBuilderAttribute.Value, attribute.Value);
         }
-
-        [Fact]
-        public void Merge_CombinesAllTagHelperOutputAndTagBuilderProperties()
-        {
-            // Arrange
-            var tagHelperOutput = new TagHelperOutput(
-                "p",
-                attributes: new Dictionary<string, string>(),
-                content: "Hello from tagHelperOutput");
-            var expectedOutputAttribute = new KeyValuePair<string, string>("class", "btn");
-            tagHelperOutput.Attributes.Add(expectedOutputAttribute);
-
-            var tagBuilder = new TagBuilder("div");
-            var expectedBuilderAttribute = new KeyValuePair<string, string>("for", "hello");
-            tagBuilder.Attributes.Add(expectedBuilderAttribute);
-            tagBuilder.InnerHtml = "Hello from tagBuilder.";
-
-            // Act
-            tagHelperOutput.Merge(tagBuilder);
-
-            // Assert
-            Assert.Equal("div", tagHelperOutput.TagName);
-            Assert.Equal("Hello from tagHelperOutputHello from tagBuilder.", tagHelperOutput.Content);
-            Assert.Equal(tagHelperOutput.Attributes.Count, 2);
-            var attribute = Assert.Single(tagHelperOutput.Attributes, kvp => kvp.Key.Equals("class"));
-            Assert.Equal(expectedOutputAttribute.Value, attribute.Value);
-            attribute = Assert.Single(tagHelperOutput.Attributes, kvp => kvp.Key.Equals("for"));
-            Assert.Equal(expectedBuilderAttribute.Value, attribute.Value);
-        }
     }
 }
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TextAreaTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TextAreaTagHelperTest.cs
index 61a69b0a9b..30bfea039b 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TextAreaTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/TextAreaTagHelperTest.cs
@@ -97,7 +97,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "name", nameAndId.Name },
                 {  "valid", "from validation attributes" },
             };
-            var expectedTagName = "textarea";
+            var expectedTagName = "not-textarea";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
 
@@ -114,7 +114,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             {
                 { "class", "form-control" },
             };
-            var output = new TagHelperOutput("original tag name", htmlAttributes, "original content")
+            var output = new TagHelperOutput(expectedTagName, htmlAttributes, "original content")
             {
                 SelfClosing = true,
             };
@@ -149,7 +149,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                 { "class", "form-control" },
             };
             var expectedContent = "original content";
-            var expectedTagName = "original tag name";
+            var expectedTagName = "textarea";
 
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var metadata = metadataProvider.GetMetadataForProperty(
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationMessageTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationMessageTagHelperTest.cs
index 13ccaa5529..b0290add45 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationMessageTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationMessageTagHelperTest.cs
@@ -20,6 +20,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
         public async Task ProcessAsync_GeneratesExpectedOutput()
         {
             // Arrange
+            var expectedTagName = "not-span";
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var modelExpression = CreateModelExpression("Name");
             var validationMessageTagHelper = new ValidationMessageTagHelper
@@ -34,7 +35,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
                     { "for", modelExpression },
                 });
             var output = new TagHelperOutput(
-                "original tag name",
+                expectedTagName,
                 attributes: new Dictionary<string, string>
                 {
                     { "id", "myvalidationmessage" }
@@ -61,7 +62,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             attribute = Assert.Single(output.Attributes, kvp => kvp.Key.Equals("data-valmsg-replace"));
             Assert.Equal("true", attribute.Value);
             Assert.Equal("Something", output.Content);
-            Assert.Equal("original tag name", output.TagName);
+            Assert.Equal(expectedTagName, output.TagName);
         }
 
         [Fact]
@@ -134,7 +135,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             await validationMessageTagHelper.ProcessAsync(context: null, output: output);
 
             // Assert
-            Assert.Equal(output.TagName, "span");
+            Assert.Equal("span", output.TagName);
             Assert.Equal(2, output.Attributes.Count);
             var attribute = Assert.Single(output.Attributes, kvp => kvp.Key.Equals("data-foo"));
             Assert.Equal("bar", attribute.Value);
diff --git a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs
index 783958a9e6..ef3197d662 100644
--- a/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs
+++ b/test/Microsoft.AspNet.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs
@@ -21,6 +21,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
         public async Task ProcessAsync_GeneratesExpectedOutput()
         {
             // Arrange
+            var expectedTagName = "not-div";
             var metadataProvider = new DataAnnotationsModelMetadataProvider();
             var validationSummaryTagHelper = new ValidationSummaryTagHelper
             {
@@ -29,7 +30,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
 
             var tagHelperContext = new TagHelperContext(new Dictionary<string, object>());
             var output = new TagHelperOutput(
-                "div",
+                expectedTagName,
                 attributes: new Dictionary<string, string>
                 {
                     { "class", "form-control" }
@@ -53,7 +54,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             Assert.Equal("true", attribute.Value);
             Assert.Equal("Custom Content<ul><li style=\"display:none\"></li>" + Environment.NewLine + "</ul>",
                          output.Content);
-            Assert.Equal("div", output.TagName);
+            Assert.Equal(expectedTagName, output.TagName);
         }
 
         [Fact]
@@ -124,7 +125,7 @@ namespace Microsoft.AspNet.Mvc.TagHelpers
             await validationSummaryTagHelper.ProcessAsync(context: null, output: output);
 
             // Assert
-            Assert.Equal(output.TagName, "div");
+            Assert.Equal("div", output.TagName);
             Assert.Equal(3, output.Attributes.Count);
             var attribute = Assert.Single(output.Attributes, kvp => kvp.Key.Equals("data-foo"));
             Assert.Equal("bar", attribute.Value);