ViewLocationExpanderContext should have a flag that indicates if the

lookup is for a full or partial view

Fixes #1212

src/Microsoft.AspNet.Mvc.Razor/DefaultViewLocationCache.cs

@@ -51,8 +51,10 @@ namespace Microsoft.AspNet.Mvc.Razor
             var routeValues = context.ActionContext.RouteData.Values;
             var controller = routeValues.GetValueOrDefault<string>(RazorViewEngine.ControllerKey);
 
-            // format is "{viewName}:{controllerName}:{areaName}:"
+            // format is "{viewName}:{isPartial}:{controllerName}:{areaName}:"
             keyBuilder.Append(context.ViewName)
+                      .Append(CacheKeySeparator)
+                      .Append(context.IsPartial ? 1 : 0)
                       .Append(CacheKeySeparator)
                       .Append(controller);
 

src/Microsoft.AspNet.Mvc.Razor/RazorViewEngine.cs

@@ -104,7 +104,7 @@ namespace Microsoft.AspNet.Mvc.Razor
                 throw new ArgumentException(Resources.ArgumentCannotBeNullOrEmpty, nameof(viewName));
             }
 
-            var pageResult = GetRazorPageResult(context, viewName);
+            var pageResult = GetRazorPageResult(context, viewName, isPartial: false);
             return CreateViewEngineResult(pageResult, _viewFactory, isPartial: false);
         }
 
@@ -117,7 +117,7 @@ namespace Microsoft.AspNet.Mvc.Razor
                 throw new ArgumentException(Resources.ArgumentCannotBeNullOrEmpty, nameof(partialViewName));
             }
 
-            var pageResult = GetRazorPageResult(context, partialViewName);
+            var pageResult = GetRazorPageResult(context, partialViewName, isPartial: true);
             return CreateViewEngineResult(pageResult, _viewFactory, isPartial: true);
         }
 
@@ -130,11 +130,12 @@ namespace Microsoft.AspNet.Mvc.Razor
                 throw new ArgumentException(Resources.ArgumentCannotBeNullOrEmpty, nameof(pageName));
             }
 
-            return GetRazorPageResult(context, pageName);
+            return GetRazorPageResult(context, pageName, isPartial: true);
         }
 
         private RazorPageResult GetRazorPageResult(ActionContext context,
-                                                   string pageName)
+                                                   string pageName,
+                                                   bool isPartial)
         {
             if (IsApplicationRelativePath(pageName))
             {
@@ -154,12 +155,13 @@ namespace Microsoft.AspNet.Mvc.Razor
             }
             else
             {
-                return LocatePageFromViewLocations(context, pageName);
+                return LocatePageFromViewLocations(context, pageName, isPartial);
             }
         }
 
         private RazorPageResult LocatePageFromViewLocations(ActionContext context,
-                                                            string pageName)
+                                                            string pageName,
+                                                            bool isPartial)
         {
             // Initialize the dictionary for the typical case of having controller and action tokens.
             var routeValues = context.RouteData.Values;
@@ -169,7 +171,7 @@ namespace Microsoft.AspNet.Mvc.Razor
             var viewLocations = !string.IsNullOrEmpty(areaName) ? AreaViewLocationFormats :
                                                                   ViewLocationFormats;
 
-            var expanderContext = new ViewLocationExpanderContext(context, pageName);
+            var expanderContext = new ViewLocationExpanderContext(context, pageName, isPartial);
             if (_viewLocationExpanders.Count > 0)
             {
                 expanderContext.Values = new Dictionary<string, string>(StringComparer.Ordinal);

src/Microsoft.AspNet.Mvc.Razor/ViewLocationExpanderContext.cs

@@ -11,22 +11,35 @@ namespace Microsoft.AspNet.Mvc.Razor
     /// </summary>
     public class ViewLocationExpanderContext
     {
+        /// <summary>
+        /// Initializes a new instance of <see cref="ViewLocationExpanderContext"/>.
+        /// </summary>
+        /// <param name="actionContext">The <see cref="Mvc.ActionContext"/> for the current executing action.</param>
+        /// <param name="viewName">The view name.</param>
+        /// <param name="isPartial">Determines if the view being discovered is a partial.</param>
         public ViewLocationExpanderContext([NotNull] ActionContext actionContext,
-                                           [NotNull] string viewName)
+                                           [NotNull] string viewName,
+                                           bool isPartial)
         {
             ActionContext = actionContext;
             ViewName = viewName;
+            IsPartial = isPartial;
         }
 
         /// <summary>
-        /// Gets the <see cref="ActionContext"/> for the current executing action.
+        /// Gets the <see cref="Mvc.ActionContext"/> for the current executing action.
         /// </summary>
-        public ActionContext ActionContext { get; private set; }
+        public ActionContext ActionContext { get; }
 
         /// <summary>
-        /// Gets the view name
+        /// Gets the view name.
         /// </summary>
-        public string ViewName { get; private set; }
+        public string ViewName { get; }
+
+        /// <summary>
+        /// Gets a value that determines if a partial view is being discovered.
+        /// </summary>
+        public bool IsPartial { get; }
 
         /// <summary>
         /// Gets or sets the <see cref="IDictionary{TKey, TValue}"/> that is populated with values as part of

test/Microsoft.AspNet.Mvc.FunctionalTests/ViewEngineTests.cs

@@ -165,6 +165,33 @@ component-content";
             Assert.Equal(expected, body.Trim());
         }
 
+        public static TheoryData ViewLocationExpanders_PassesInIsPartialToViewLocationExpanderContextData
+        {
+            get
+            {
+                return new TheoryData<string, string>
+                {
+                    { "Index", "<expander-view><shared-views>/Shared-Views/ExpanderViews/_ExpanderPartial.cshtml</shared-views></expander-view>" },
+                    { "Partial", "<shared-views>/Shared-Views/ExpanderViews/_ExpanderPartial.cshtml</shared-views>" }
+                };
+            }
+        }
+
+        [Theory]
+        [MemberData(nameof(ViewLocationExpanders_PassesInIsPartialToViewLocationExpanderContextData))]
+        public async Task ViewLocationExpanders_PassesInIsPartialToViewLocationExpanderContext(string action, string expected)
+        {
+            // Arrange
+            var server = TestServer.Create(_provider, _app);
+            var client = server.CreateClient();
+
+            // Act
+            var body = await client.GetStringAsync($"http://localhost/ExpanderViews/{action}");
+
+            // Assert
+            Assert.Equal(expected, body.Trim());
+        }
+
         public static IEnumerable<object[]> RazorViewEngine_RendersPartialViewsData
         {
             get

test/Microsoft.AspNet.Mvc.Razor.Test/DefaultViewLocationCacheTest.cs

@@ -15,10 +15,12 @@ namespace Microsoft.AspNet.Mvc.Razor
         {
             get
             {
-                yield return new[] { new ViewLocationExpanderContext(GetActionContext(), "test") };
+                yield return new[] { new ViewLocationExpanderContext(GetActionContext(), "test", isPartial: false) };
+                yield return new[] { new ViewLocationExpanderContext(GetActionContext(), "test", isPartial: true) };
 
                 var areaActionContext = GetActionContext("controller2", "myarea");
-                yield return new[] { new ViewLocationExpanderContext(areaActionContext, "test2") };
+                yield return new[] { new ViewLocationExpanderContext(areaActionContext, "test2", isPartial: false) };
+                yield return new[] { new ViewLocationExpanderContext(areaActionContext, "test2", isPartial: true) };
 
                 var actionContext = GetActionContext("controller3", "area3");
                 var values = new Dictionary<string, string>(StringComparer.Ordinal)
@@ -26,11 +28,16 @@ namespace Microsoft.AspNet.Mvc.Razor
                     { "culture", "fr" },
                     { "theme", "sleek" }
                 };
-                var expanderContext = new ViewLocationExpanderContext(actionContext, "test3")
+                var expanderContext = new ViewLocationExpanderContext(actionContext, "test3", isPartial: false)
                 {
                     Values = values
                 };
+                yield return new[] { expanderContext };
 
+                expanderContext = new ViewLocationExpanderContext(actionContext, "test3", isPartial: true)
+                {
+                    Values = values
+                };
                 yield return new[] { expanderContext };
             }
         }
@@ -71,15 +78,26 @@ namespace Microsoft.AspNet.Mvc.Razor
             {
                 yield return new object[]
                 {
-                    new ViewLocationExpanderContext(GetActionContext(), "test"),
+                    new ViewLocationExpanderContext(GetActionContext(), "test", isPartial: false),
-                    "test:mycontroller"
+                    "test:0:mycontroller"
+                };
+
+                yield return new object[]
+                {
+                    new ViewLocationExpanderContext(GetActionContext(), "test", isPartial: true),
+                    "test:1:mycontroller"
                 };
 
                 var areaActionContext = GetActionContext("controller2", "myarea");
                 yield return new object[]
                 {
-                    new ViewLocationExpanderContext(areaActionContext, "test2"),
+                    new ViewLocationExpanderContext(areaActionContext, "test2", isPartial: false),
-                    "test2:controller2:myarea"
+                    "test2:0:controller2:myarea"
+                };
+                yield return new object[]
+                {
+                    new ViewLocationExpanderContext(areaActionContext, "test2", isPartial: true),
+                    "test2:1:controller2:myarea"
                 };
 
                 var actionContext = GetActionContext("controller3", "area3");
@@ -88,7 +106,7 @@ namespace Microsoft.AspNet.Mvc.Razor
                     { "culture", "fr" },
                     { "theme", "sleek" }
                 };
-                var expanderContext = new ViewLocationExpanderContext(actionContext, "test3")
+                var expanderContext = new ViewLocationExpanderContext(actionContext, "test3", isPartial: false)
                 {
                     Values = values
                 };
@@ -96,7 +114,17 @@ namespace Microsoft.AspNet.Mvc.Razor
                 yield return new object[]
                 {
                     expanderContext,
-                    "test3:controller3:area3:culture:fr:theme:sleek"
+                    "test3:0:controller3:area3:culture:fr:theme:sleek"
+                };
+
+                expanderContext = new ViewLocationExpanderContext(actionContext, "test3", isPartial: true)
+                {
+                    Values = values
+                };
+                yield return new object[]
+                {
+                    expanderContext,
+                    "test3:1:controller3:area3:culture:fr:theme:sleek"
                 };
             }
         }

test/WebSites/RazorWebSite/Controllers/ExpanderViewsController.cs

@@ -0,0 +1,21 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Mvc;
+
+namespace RazorWebSite.Controllers
+{
+    public class ExpanderViewsController : Controller
+    {
+        // This result discovers the Index.cshtml from /View but the partial is executed from /Shared-Views
+        public ViewResult Index()
+        {
+            return View();
+        }
+
+        public PartialViewResult Partial()
+        {
+            return PartialView("_ExpanderPartial");
+        }
+    }
+}

test/WebSites/RazorWebSite/Services/CustomPartialDirectoryViewLocationExpander.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using Microsoft.AspNet.Mvc.Razor;
+
+namespace RazorWebSite
+{
+    public class CustomPartialDirectoryViewLocationExpander : IViewLocationExpander
+    {
+        public void PopulateValues(ViewLocationExpanderContext context)
+        {
+        }
+
+        public virtual IEnumerable<string> ExpandViewLocations(ViewLocationExpanderContext context,
+                                                               IEnumerable<string> viewLocations)
+        {
+            if (context.IsPartial)
+            {
+                return ExpandViewLocationsCore(viewLocations);
+            }
+
+            return viewLocations;
+        }
+
+        private IEnumerable<string> ExpandViewLocationsCore(IEnumerable<string> viewLocations)
+        {
+            foreach (var location in viewLocations)
+            {
+                yield return "/Shared-Views/{1}/{0}.cshtml";
+                yield return location;
+            }
+        }
+    }
+}

test/WebSites/RazorWebSite/Shared-Views/ExpanderViews/Index.cshtml

@@ -0,0 +1,3 @@
+@{ 
+    throw new Exception("This view should not be executed");
+}

test/WebSites/RazorWebSite/Shared-Views/ExpanderViews/_ExpanderPartial.cshtml

@@ -0,0 +1 @@
+<shared-views>@ViewContext.View.Path</shared-views>

test/WebSites/RazorWebSite/Startup.cs

@@ -27,6 +27,7 @@ namespace RazorWebSite
                     var expander = new LanguageViewLocationExpander(
                             context => context.HttpContext.Request.Query["language-expander-value"]);
                     options.ViewLocationExpanders.Add(expander);
+                    options.ViewLocationExpanders.Add(new CustomPartialDirectoryViewLocationExpander());
                 });
             });
 

test/WebSites/RazorWebSite/Views/ExpanderViews/Index.cshtml

@@ -0,0 +1 @@
+<expander-view>@Html.Partial("_ExpanderPartial")</expander-view>