Address PR II comments for <input/> tag helper

- also catch up to match recent changes made in this branch

nit: deliniate attribute names in other resource strings

Author: dougbu

src/Microsoft.AspNet.Mvc.TagHelpers/InputTagHelper.cs

@@ -53,11 +53,13 @@ public class InputTagHelper : TagHelper
                 { "time", "{0:HH:mm:ss.fff}" },
             };
 
+        // Protected to ensure subclasses are correctly activated. Internal for ease of use when testing.
         [Activate]
-        private IHtmlGenerator Generator { get; set; }
+        protected internal IHtmlGenerator Generator { get; set; }
 
+        // Protected to ensure subclasses are correctly activated. Internal for ease of use when testing.
         [Activate]
-        private ViewContext ViewContext { get; set; }
+        protected internal ViewContext ViewContext { get; set; }
 
         /// <summary>
         /// An expression to be evaluated against the current model.
@@ -70,28 +72,34 @@ public class InputTagHelper : TagHelper
         /// attribute to that formatted <see cref="string"/>.
         /// </summary>
         /// <remarks>
-        /// Used only if <see cref="Value "/> is <c>null</c> and <see cref="Process"/> calls
+        /// Used only the calculated "type" attribute is "text" (the most common value) e.g.
+        /// <see cref="InputTypeName"/> is "String". That is, <see cref="Format"/> is used when calling
         /// <see cref="IHtmlGenerator.GenerateTextBox"/>.
         /// </remarks>
         public string Format { get; set; }
 
         /// <summary>
-        /// The type of the &lt;input&gt; element. Passed through to the generated HTML in all cases. Also used to
-        /// determine the <see cref="IHtmlGenerator"/> helper <see cref="Process"/> will call and the default
-        /// <see cref="Format"/> value.
+        /// The type of the &lt;input&gt; element.
         /// </summary>
+        /// <remarks>
+        /// Passed through to the generated HTML in all cases. Also used to determine the <see cref="IHtmlGenerator"/>
+        /// helper to call and the default <see cref="Format"/> value (when calling
+        /// <see cref="IHtmlGenerator.GenerateTextBox"/>).
+        /// </remarks>
         [HtmlAttributeName("type")]
         public string InputTypeName { get; set; }
 
         /// <summary>
-        /// The value of the &lt;input&gt; element. Passed through to the generated HTML in all cases. Also used to
-        /// determine the generated "checked" attribute if <see cref="InputTypeName"/> is "radio".
+        /// The value of the &lt;input&gt; element.
         /// </summary>
-        /// <remarks>Must not be <c>null</c> if <see cref="InputTypeName"/> is "radio".</remarks>
+        /// <remarks>
+        /// Passed through to the generated HTML in all cases. Also used to determine the generated "checked" attribute
+        /// if <see cref="InputTypeName"/> is "radio". Must not be <c>null</c> in that case.
+        /// </remarks>
         public string Value { get; set; }
 
         /// <inheritdoc />
-        /// <remarks>Does nothing unless user binds "for" attribute in Razor source.</remarks>
+        /// <remarks>Does nothing if <see cref="For"/> is <c>null</c></remarks>
         public override void Process(TagHelperContext context, TagHelperOutput output)
         {
             // Pass through attributes that are also well-known HTML attributes. Must be done prior to any copying
@@ -112,6 +120,7 @@ public override void Process(TagHelperContext context, TagHelperOutput output)
                 if (Format != null)
                 {
                     throw new InvalidOperationException(Resources.FormatInputTagHelper_UnableToFormat(
+                        "<input>",
                         nameof(For).ToLowerInvariant(),
                         nameof(Format).ToLowerInvariant()));
                 }
@@ -124,6 +133,8 @@ public override void Process(TagHelperContext context, TagHelperOutput output)
                 if (metadata == null)
                 {
                     throw new InvalidOperationException(Resources.FormatTagHelpers_NoProvidedMetadata(
+                        "<input>",
+                        nameof(For).ToLowerInvariant(),
                         nameof(IModelMetadataProvider),
                         For.Name));
                 }
@@ -143,7 +154,9 @@ public override void Process(TagHelperContext context, TagHelperOutput output)
                 if (!string.IsNullOrEmpty(inputType))
                 {
                     // inputType may be more specific than default the generator chooses below.
-                    if (!output.Attributes.ContainsKey("type"))
+                    // TODO: Use Attributes.ContainsKey once aspnet/Razor#186 is fixed.
+                    if (!output.Attributes.Any(
+                        item => string.Equals("type", item.Key, StringComparison.OrdinalIgnoreCase)))
                     {
                         output.Attributes["type"] = inputType;
                     }
@@ -186,6 +199,8 @@ public override void Process(TagHelperContext context, TagHelperOutput output)
 
                 if (tagBuilder != null)
                 {
+                    // 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.SelfClosing = true;
                     output.Merge(tagBuilder);
                 }
@@ -197,10 +212,11 @@ private void GenerateCheckBox(ModelMetadata metadata, TagHelperOutput output)
             if (typeof(bool) != metadata.RealModelType)
             {
                 throw new InvalidOperationException(Resources.FormatInputTagHelper_InvalidExpressionResult(
-                    metadata.RealModelType.FullName,
+                    "<input>",
                     nameof(For).ToLowerInvariant(),
+                    metadata.RealModelType.FullName,
                     typeof(bool).FullName,
-                    nameof(InputTypeName).ToLowerInvariant(),
+                    "type",
                     "checkbox"));
             }
 
@@ -239,6 +255,7 @@ private TagBuilder GenerateRadio(ModelMetadata metadata)
             if (Value == null)
             {
                 throw new InvalidOperationException(Resources.FormatInputTagHelper_ValueRequired(
+                    "<input>",
                     nameof(Value).ToLowerInvariant(),
                     "type",
                     "radio"));

src/Microsoft.AspNet.Mvc.TagHelpers/Properties/Resources.Designer.cs

@@ -118,27 +118,27 @@
     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
   </resheader>
   <data name="AnchorTagHelper_CannotDetermineHrefRouteActionOrControllerSpecified" xml:space="preserve">
-    <value>Cannot determine an {4} for {0}. An {0} with a specified {1} must not have an {2} or {3} attribute.</value>
+    <value>Cannot determine an '{4}' for {0}. An {0} with a specified '{1}' must not have an '{2}' or '{3}' attribute.</value>
   </data>
   <data name="AnchorTagHelper_CannotOverrideSpecifiedHref" xml:space="preserve">
-    <value>Cannot determine an {8} for {0}. An {0} with a specified {8} must not have attributes starting with {7} or an {1}, {2}, {3}, {4}, {5} or {6} attribute.</value>
+    <value>Cannot determine an '{8}' for {0}. An {0} with a specified '{8}' must not have attributes starting with '{7}' or an '{1}', '{2}', '{3}', '{4}', '{5}', or '{6}' attribute.</value>
   </data>
   <data name="InputTagHelper_InvalidExpressionResult" xml:space="preserve">
-    <value>Unexpected '{1}' result type '{0}'. '{1}' must be of type '{2}' if '{3}' is '{4}'.</value>
+    <value>Unexpected '{1}' expression result type '{2}' for {0}. '{1}' must be of type '{3}' if '{4}' is '{5}'.</value>
   </data>
   <data name="InputTagHelper_UnableToFormat" xml:space="preserve">
-    <value>Unable to format without a '{0}' expression. '{1}' must be null if '{0}' is null.</value>
+    <value>Unable to format without a '{1}' expression for {0}. '{2}' must be null if '{1}' is null.</value>
   </data>
   <data name="InputTagHelper_ValueRequired" xml:space="preserve">
-    <value>'{0}' must not be null if '{1}' is '{2}'.</value>
+    <value>'{1}' must not be null for {0} if '{2}' is '{3}'.</value>
   </data>
   <data name="FormTagHelper_CannotDetermineAction" xml:space="preserve">
-    <value>Cannot determine an {1} for {0}. A {0} with a URL-based {1} must not have attributes starting with {3} or a {2} attribute.</value>
+    <value>Cannot determine an '{1}' for {0}. A {0} with a URL-based '{1}' must not have attributes starting with '{3}' or a '{2}' attribute.</value>
   </data>
   <data name="ValidationSummaryTagHelper_InvalidValidationSummaryValue" xml:space="preserve">
     <value>Cannot parse '{1}' value '{2}' for {0}. Acceptable values are '{3}', '{4}' and '{5}'.</value>
   </data>
   <data name="TagHelpers_NoProvidedMetadata" xml:space="preserve">
-    <value>The {0} was unable to provide metadata for expression '{1}'.</value>
+    <value>The {2} was unable to provide metadata about '{1}' expression value '{3}' for {0}.</value>
   </data>
 </root>

src/Microsoft.AspNet.Mvc.TagHelpers/Resources.resx

@@ -89,7 +89,9 @@ public static void MergeAttributes(this TagHelperOutput tagHelperOutput, TagBuil
         {
             foreach (var attribute in tagBuilder.Attributes)
             {
-                if (!tagHelperOutput.Attributes.ContainsKey(attribute.Key))
+                // TODO: Use Attributes.ContainsKey once aspnet/Razor#186 is fixed.
+                if (!tagHelperOutput.Attributes.Any(
+                    item => string.Equals(attribute.Key, item.Key, StringComparison.OrdinalIgnoreCase)))
                 {
                     tagHelperOutput.Attributes.Add(attribute.Key, attribute.Value);
                 }

src/Microsoft.AspNet.Mvc.TagHelpers/TagHelperOutputExtensions.cs

@@ -176,9 +176,9 @@ public async Task ProcessAsync_ThrowsIfHrefConflictsWithBoundAttributes(string p
                 typeof(AnchorTagHelper).GetProperty(propertyName).SetValue(anchorTagHelper, "Home");
             }
 
-            var expectedErrorMessage = "Cannot determine an href for <a>. An <a> with a specified href must not " +
-                                       "have attributes starting with route- or an action, controller, route, " +
-                                       "protocol, host or fragment attribute.";
+            var expectedErrorMessage = "Cannot determine an 'href' for <a>. An <a> with a specified 'href' must not " +
+                                       "have attributes starting with 'route-' or an 'action', 'controller', " +
+                                       "'route', 'protocol', 'host', or 'fragment' attribute.";
 
             // Act & Assert
             var ex = await Assert.ThrowsAsync<InvalidOperationException>(
@@ -202,8 +202,8 @@ public async Task ProcessAsync_ThrowsIfRouteAndActionOrControllerProvided(string
                 "a",
                 attributes: new Dictionary<string, string>(),
                 content: string.Empty);
-            var expectedErrorMessage = "Cannot determine an href for <a>. An <a> with a " +
-                                       "specified route must not have an action or controller attribute.";
+            var expectedErrorMessage = "Cannot determine an 'href' for <a>. An <a> with a " +
+                                       "specified 'route' must not have an 'action' or 'controller' attribute.";
 
             // Act & Assert
             var ex = await Assert.ThrowsAsync<InvalidOperationException>(