Handle Unknown Tags

I added code to detect unknown tags and throw an exception. I also
provided a default implementation so tags are in the global scope by
default.

mustache-sharp.test/FormatCompilerTester.cs

@@ -741,10 +741,11 @@ Last";
         }
 
         /// <summary>
-        /// Second else blocks will be interpreted as just another piece of text.
+        /// Second else blocks will result in an exceptions being thrown.
         /// </summary>
         [TestMethod]
-        public void TestCompile_IfElse_TwoElses_IncludesSecondElseInElse()
+        [ExpectedException(typeof(FormatException))]
+        public void TestCompile_IfElse_TwoElses_IncludesSecondElseInElse_Throws()
         {
             FormatCompiler parser = new FormatCompiler();
             const string format = "Before{{#if this}}Yay{{#else}}Nay{{#else}}Bad{{/if}}After";
@@ -910,7 +911,7 @@ Last";
                 return new TagParameter[] { new TagParameter("param") { IsRequired = false, DefaultValue = 123 } };
             }
 
-            public override string Decorate(IFormatProvider provider, Dictionary<string, object> arguments)
+            protected override string GetText(IFormatProvider provider, Dictionary<string, object> arguments)
             {
                 return arguments["param"].ToString();
             }

mustache-sharp.test/Properties/AssemblyInfo.cs

@@ -31,5 +31,5 @@ using System.Runtime.InteropServices;
 //
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
-[assembly: AssemblyVersion("1.0.0.0")]
-[assembly: AssemblyFileVersion("1.0.0.0")]
+[assembly: AssemblyVersion("0.0.1.0")]
+[assembly: AssemblyFileVersion("0.0.1.0")]

mustache-sharp/FormatCompiler.cs

@@ -106,6 +106,7 @@ namespace mustache
                     TagDefinition childDefinition = _tagLookup[childTag];
                     matches.Add(getTagRegex(childDefinition));
                 }
+                matches.Add(getUnknownTagRegex());
                 string match = "{{(" + String.Join("|", matches) + ")}}";
                 regex = new Regex(match, RegexOptions.Compiled);
                 _regexLookup.Add(definition.Name, regex);
@@ -153,6 +154,11 @@ namespace mustache
             return regexBuilder.ToString();
         }
 
+        private string getUnknownTagRegex()
+        {
+            return @"(?<unknown>(#.*?))";
+        }
+
         private int buildCompoundGenerator(
             TagDefinition tagDefinition, 
             CompoundGenerator generator,
@@ -229,6 +235,10 @@ namespace mustache
                     generator.AddStaticGenerators(trimmer.RecordText(leading, true, false));
                     formatIndex = match.Index + match.Length;
                 }
+                else if (match.Groups["unknown"].Success)
+                {
+                    throw new FormatException(Resources.UnknownTag);
+                }
             }
             return formatIndex;
         }

mustache-sharp/InlineTagDefinition.cs

@@ -36,11 +36,24 @@ namespace mustache
             return false;
         }
 
+        /// <summary>
+        /// Generates the text for the tag.
+        /// </summary>
+        /// <param name="provider">The format provider to use.</param>
+        /// <param name="innerText">The text to decorate. This will always be an empty string.</param>
+        /// <param name="arguments">The arguments passed to the tag.</param>
+        /// <returns>The generated text.</returns>
         public sealed override string Decorate(IFormatProvider provider, string innerText, Dictionary<string, object> arguments)
         {
-            return Decorate(provider, arguments);
+            return GetText(provider, arguments);
         }
 
-        public abstract string Decorate(IFormatProvider provider, Dictionary<string, object> arguments);
+        /// <summary>
+        /// Gets the text of the inline tag.
+        /// </summary>
+        /// <param name="provider">The format provider to use.</param>
+        /// <param name="arguments">The arguments passed to the tag.</param>
+        /// <returns>The generated text.</returns>
+        protected abstract string GetText(IFormatProvider provider, Dictionary<string, object> arguments);
     }
 }

mustache-sharp/Properties/AssemblyInfo.cs

@@ -34,6 +34,6 @@ using System.Runtime.CompilerServices;
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.0.0.0")]
-[assembly: AssemblyFileVersion("0.0.0.0")]
+[assembly: AssemblyVersion("0.0.1.0")]
+[assembly: AssemblyFileVersion("0.0.1.0")]
 [assembly: InternalsVisibleTo("mustache-sharp.test")]

mustache-sharp/Properties/Resources.Designer.cs

@@ -115,7 +115,7 @@ namespace mustache.Properties {
         }
         
         /// <summary>
-        ///   Looks up a localized string similar to Encountered an unknown tag {0}..
+        ///   Looks up a localized string similar to Encountered an unknown tag. It was either not registered or exists in a different context..
         /// </summary>
         internal static string UnknownTag {
             get {

mustache-sharp/Properties/Resources.resx

@@ -136,7 +136,7 @@
     <value>Expected a matching {0} tag but none was found.</value>
   </data>
   <data name="UnknownTag" xml:space="preserve">
-    <value>Encountered an unknown tag {0}.</value>
+    <value>Encountered an unknown tag. It was either not registered or exists in a different context.</value>
   </data>
   <data name="WrongNumberOfArguments" xml:space="preserve">
     <value>The wrong number of arguments were passed to an {0} tag.</value>

mustache-sharp/TagDefinition.cs

@@ -55,7 +55,10 @@ namespace mustache
         /// <summary>
         /// Gets whether a tag is limited to the parent tag's context.
         /// </summary>
-        protected abstract bool GetIsContextSensitive();
+        protected virtual bool GetIsContextSensitive()
+        {
+            return false;
+        }
 
         /// <summary>
         /// Gets the parameters that are defined for the tag.