Suppress validation summary <div> when nothing is generated

- aspnet#2372 - make the `ValidationSummaryTagHelper` behave consistently with `Html.ValidationSummar()`
cjrosa · Sep 27, 2016 · 0a4c06e · 0a4c06e
1 parent 6cdd045
commit 0a4c06e
Show file tree

Hide file tree

Showing 4 changed files with 18 additions and 21 deletions.
diff --git a/src/Microsoft.AspNetCore.Mvc.TagHelpers/ValidationSummaryTagHelper.cs b/src/Microsoft.AspNetCore.Mvc.TagHelpers/ValidationSummaryTagHelper.cs
@@ -104,11 +104,15 @@ public override void Process(TagHelperContext context, TagHelperOutput output)
                 message: null,
                 headerTag: null,
                 htmlAttributes: null);
-            if (tagBuilder != null)
+            if (tagBuilder == null)
             {
-                output.MergeAttributes(tagBuilder);
-                output.PostContent.AppendHtml(tagBuilder.InnerHtml);
+                // The generator determined no element was necessary.
+                output.SuppressOutput();
+                return;
             }
+
+            output.MergeAttributes(tagBuilder);
+            output.PostContent.AppendHtml(tagBuilder.InnerHtml);
         }
     }
 }
diff --git a/...nctionalTests/compiler/resources/HtmlGenerationWebSite.HtmlGeneration_Customer.Index.html b/...nctionalTests/compiler/resources/HtmlGenerationWebSite.HtmlGeneration_Customer.Index.html
@@ -33,7 +33,7 @@
         <div class="order validation-summary-errors" data-valmsg-summary="true"><ul><li>The value &#x27;&#x27; is invalid.</li>
 <li>The Password field is required.</li>
 </ul></div>
-        <div class="order"></div>
+
         <input type="submit"/>
     <input name="__RequestVerificationToken" type="hidden" value="{0}" /></form>
 </body>

diff --git a/...unctionalTests/compiler/resources/HtmlGenerationWebSite.HtmlGeneration_Home.Customer.html b/...unctionalTests/compiler/resources/HtmlGenerationWebSite.HtmlGeneration_Home.Customer.html
@@ -32,7 +32,7 @@
         </div>
         <div class="order validation-summary-valid" data-valmsg-summary="true"><ul><li style="display:none"></li>
 </ul></div>
-        <div class="order"></div>
+
         <input type="submit"/>
     <input name="__RequestVerificationToken" type="hidden" value="{0}" /></form>
 </body>

diff --git a/test/Microsoft.AspNetCore.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs b/test/Microsoft.AspNetCore.Mvc.TagHelpers.Test/ValidationSummaryTagHelperTest.cs
@@ -10,6 +10,7 @@
 using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Mvc.ModelBinding;
 using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.TestCommon;
 using Microsoft.AspNetCore.Mvc.ViewEngines;
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
 using Microsoft.AspNetCore.Razor.TagHelpers;
@@ -96,7 +97,7 @@ public async Task ProcessAsync_GeneratesExpectedOutput_WithNoErrors(ModelStateDi
 
         [Theory]
         [MemberData(nameof(ProcessAsync_GeneratesExpectedOutput_WithNoErrorsData))]
-        public async Task ProcessAsync_DoesNothingIfClientSideValiationDisabled_WithNoErrorsData(
+        public async Task ProcessAsync_SuppressesOutput_IfClientSideValiationDisabled_WithNoErrorsData(
             ModelStateDictionary modelStateDictionary)
         {
             // Arrange
@@ -128,16 +129,12 @@ public async Task ProcessAsync_DoesNothingIfClientSideValiationDisabled_WithNoEr
             await validationSummaryTagHelper.ProcessAsync(context, output);
 
             // Assert
-            Assert.Equal("div", output.TagName);
+            Assert.Null(output.TagName);
             Assert.Empty(output.Attributes);
-            Assert.False(output.IsContentModified);
-            Assert.False(output.PreContent.IsModified);
-            Assert.False(output.PreElement.IsModified);
-            Assert.False(output.PostContent.IsModified);
-            Assert.False(output.PostElement.IsModified);
+            Assert.Empty(HtmlContentUtilities.HtmlContentToString(output));
         }
 
-        public static TheoryData<string, ModelStateDictionary> ProcessAsync_DoesNothingIfModelOnly_WithNoModelErrorData
+        public static TheoryData<string, ModelStateDictionary> ProcessAsync_SuppressesOutput_IfModelOnlyWithNoModelErrorData
         {
             get
             {
@@ -165,8 +162,8 @@ public static TheoryData<string, ModelStateDictionary> ProcessAsync_DoesNothingI
         }
 
         [Theory]
-        [MemberData(nameof(ProcessAsync_DoesNothingIfModelOnly_WithNoModelErrorData))]
-        public async Task ProcessAsync_DoesNothingIfModelOnly_WithNoModelError(
+        [MemberData(nameof(ProcessAsync_SuppressesOutput_IfModelOnlyWithNoModelErrorData))]
+        public async Task ProcessAsync_SuppressesOutput_IfModelOnly_WithNoModelError(
             string prefix,
             ModelStateDictionary modelStateDictionary)
         {
@@ -199,13 +196,9 @@ public async Task ProcessAsync_DoesNothingIfModelOnly_WithNoModelError(
             await validationSummaryTagHelper.ProcessAsync(context, output);
 
             // Assert
-            Assert.Equal("div", output.TagName);
+            Assert.Null(output.TagName);
             Assert.Empty(output.Attributes);
-            Assert.False(output.IsContentModified);
-            Assert.False(output.PreContent.IsModified);
-            Assert.False(output.PreElement.IsModified);
-            Assert.False(output.PostContent.IsModified);
-            Assert.False(output.PostElement.IsModified);
+            Assert.Empty(HtmlContentUtilities.HtmlContentToString(output));
         }
 
         [Theory]