Added support for path expansion

SuperSimpleViewEngine.Tests/FakeViewEngineHost.cs

@@ -5,6 +5,7 @@ namespace SuperSimpleViewEngine.Tests
     public class FakeViewEngineHost : IViewEngineHost
     {
         public Func<string, object, string> GetTemplateCallback { get; set; }
+        public Func<string, string> ExpandPathCallBack { get; set; }
 
         /// <summary>
         /// Html "safe" encode a string
@@ -40,5 +41,15 @@ public string GetUriString(string name, params string[] parameters)
         {
             throw new NotImplementedException();
         }
+
+        /// <summary>
+        /// Expands a path to include any base paths
+        /// </summary>
+        /// <param name="path">Path to expand</param>
+        /// <returns>Expanded path</returns>
+        public string ExpandPath(string path)
+        {
+            return this.ExpandPathCallBack != null ? this.ExpandPathCallBack.Invoke(path) : path;
+        }
     }
 }

SuperSimpleViewEngine.Tests/SuperSimpleViewEngineTests.cs

@@ -653,13 +653,25 @@ public void Should_handle_master_page_hierarchies()
 
             var fakeViewEngineHost = new FakeViewEngineHost();
             fakeViewEngineHost.GetTemplateCallback = (s, m) => s == "middle" ? middle : top;
-
             var viewEngine = new SuperSimpleViewEngine(fakeViewEngineHost);
 
             var result = viewEngine.Render(input, null);
 
             Assert.Equal("Top! Top\r\nMiddle", result);
         }
+
+        [Fact]
+        public void Should_call_to_expand_paths()
+        {
+            const string input = @"<script src='@Path['~/scripts/test.js']'></script>";
+            var fakeViewEngineHost = new FakeViewEngineHost();
+            fakeViewEngineHost.ExpandPathCallBack = s => s.Replace("~/", "/BasePath/");
+            var viewEngine = new SuperSimpleViewEngine(fakeViewEngineHost);
+
+            var result = viewEngine.Render(input, null);
+
+            Assert.Equal("<script src='/BasePath/scripts/test.js'></script>", result);
+        }
     }
 
     public class User

SuperSimpleViewEngine/IViewEngineHost.cs

@@ -28,5 +28,12 @@ public interface IViewEngineHost
         /// <param name="parameters">Parameters to use to expand the uri string</param>
         /// <returns>Expanded uri string, or null if not found</returns>
         string GetUriString(string name, params string[] parameters);
+
+        /// <summary>
+        /// Expands a path to include any base paths
+        /// </summary>
+        /// <param name="path">Path to expand</param>
+        /// <returns>Expanded path</returns>
+        string ExpandPath(string path);
     }
 }

SuperSimpleViewEngine/SuperSimpleViewEngine.cs

@@ -54,6 +54,11 @@ public class SuperSimpleViewEngine
         /// </summary>
         private readonly Regex masterPageHeaderRegEx = new Regex(@"^(?:@Master\[\'(?<MasterPage>.+?)\'\]);?", RegexOptions.Compiled);
 
+        /// <summary>
+        /// Compiled RegEx for path expansion
+        /// </summary>
+        private readonly Regex pathExpansionRegEx = new Regex(@"(?:@Path\[\'(?<Path>.+?)\'\]);?", RegexOptions.Compiled);
+
         /// <summary>
         /// View engine transform processors
         /// </summary>
@@ -76,6 +81,7 @@ public SuperSimpleViewEngine(IViewEngineHost viewEngineHost)
                     this.PerformSingleSubstitutions,
                     this.PerformEachSubstitutions,
                     this.PerformConditionalSubstitutions,
+                    this.PerformPathSubstitutions,
                     this.PerformPartialSubstitutions,
                     this.PerformMasterPageSubstitutions,
                 };
@@ -402,6 +408,28 @@ private string PerformConditionalSubstitutions(string template, object model)
             return result;
         }
 
+        /// <summary>
+        /// Perform path expansion substitutions
+        /// </summary>
+        /// <param name="template">The template.</param>
+        /// <param name="model">The model.</param>
+        /// <returns>Template with paths expanded</returns>
+        private string PerformPathSubstitutions(string template, object model)
+        {
+            var result = template;
+
+            result = this.pathExpansionRegEx.Replace(
+                result,
+                m =>
+                {
+                    var path = m.Groups["Path"].Value;
+
+                    return this.viewEngineHost.ExpandPath(path);
+                });
+
+            return result;
+        }
+
         /// <summary>
         /// Perform @Partial partial view expansion
         /// </summary>