Allow Cultures Within Names For EmbeddedResources

src/Tasks.UnitTests/CreateCSharpManifestResourceName_Tests.cs

@@ -266,6 +266,29 @@ public void RootnamespaceWithCulture()
             Assert.Equal("RootNamespace.SubFolder.MyForm.en-GB", result);
         }
 
+        /// <summary>
+        /// Explicitly retain culture
+        /// </summary>
+        [Fact]
+        public void RootnamespaceWithCulture_RetainCultureInFileName()
+        {
+            string result =
+            CreateCSharpManifestResourceName.CreateManifestNameImpl
+                (
+                    @"Subfolder\File.cs.cshtml",
+                    null,
+                    true,
+                    "RootNamespace",        // Root namespace
+                    null,
+                    null,
+                    null,
+                    null,
+                    true // retain culture in name
+                );
+
+            result.ShouldBe("RootNamespace.Subfolder.File.cs.cshtml");
+        }
+
         /// <summary>
         /// If there is a link file name then it is preferred over the main file name.
         /// </summary>

src/Tasks/AssignCulture.cs

@@ -133,7 +133,10 @@ public override bool Execute()
                     Culture.ItemCultureInfo info = Culture.GetItemCultureInfo
                         (
                             AssignedFiles[i].ItemSpec,
-                            dependentUpon
+                            dependentUpon,
+                            // If 'WithCulture' is explicitly set to false, treat as 'culture-neutral' and keep the original name of the resource.
+                            // https://github.com/dotnet/msbuild/issues/3064
+                            AssignedFiles[i].GetMetadata("WithCulture").Equals("false", StringComparison.OrdinalIgnoreCase)
                         );
 
                     if (!string.IsNullOrEmpty(info.culture))

src/Tasks/CreateCSharpManifestResourceName.cs

@@ -39,9 +39,13 @@ Stream binaryStream
         )
         {
             string culture = null;
+            bool treatAsCultureNeutral = false;
             if (fileName != null && itemSpecToTaskitem.TryGetValue(fileName, out ITaskItem item))
             {
                 culture = item.GetMetadata("Culture");
+                // If 'WithCulture' is explicitly set to false, treat as 'culture-neutral' and keep the original name of the resource.
+                // https://github.com/dotnet/msbuild/issues/3064
+                treatAsCultureNeutral = item.GetMetadata("WithCulture").Equals("false", StringComparison.OrdinalIgnoreCase);
             }
 
             /*
@@ -59,7 +63,8 @@ Stream binaryStream
                 dependentUponFileName,
                 culture,
                 binaryStream,
-                Log
+                Log,
+                treatAsCultureNeutral
             );
         }
 
@@ -78,6 +83,7 @@ Stream binaryStream
         /// <param name="culture">The override culture of this resource, if any</param>
         /// <param name="binaryStream">File contents binary stream, may be null</param>
         /// <param name="log">Task's TaskLoggingHelper, for logging warnings or errors</param>
+        /// <param name="treatAsCultureNeutral">Whether to treat the current file as 'culture-neutral' and retain the culture in the name.</param>
         /// <returns>Returns the manifest name</returns>
         internal static string CreateManifestNameImpl
         (
@@ -88,7 +94,8 @@ internal static string CreateManifestNameImpl
             string dependentUponFileName, // May be null
             string culture, // may be null 
             Stream binaryStream, // File contents binary stream, may be null
-            TaskLoggingHelper log
+            TaskLoggingHelper log,
+            bool treatAsCultureNeutral = false
         )
         {
             // Use the link file name if there is one, otherwise, fall back to file name.
@@ -99,7 +106,7 @@ TaskLoggingHelper log
             }
 
             dependentUponFileName = FileUtilities.FixFilePath(dependentUponFileName);
-            Culture.ItemCultureInfo info = Culture.GetItemCultureInfo(embeddedFileName, dependentUponFileName);
+            Culture.ItemCultureInfo info = Culture.GetItemCultureInfo(embeddedFileName, dependentUponFileName, treatAsCultureNeutral);
 
             // If the item has a culture override, respect that. 
             if (!string.IsNullOrEmpty(culture))

src/Tasks/CreateVisualBasicManifestResourceName.cs

@@ -37,9 +37,13 @@ protected override string CreateManifestName
         )
         {
             string culture = null;
+            bool treatAsCultureNeutral = false;
             if (fileName != null && itemSpecToTaskitem.TryGetValue(fileName, out ITaskItem item))
             {
                 culture = item.GetMetadata("Culture");
+                // If 'WithCulture' is explicitly set to false, treat as 'culture-neutral' and keep the original name of the resource.
+                // https://github.com/dotnet/msbuild/issues/3064
+                treatAsCultureNeutral = item.GetMetadata("WithCulture").Equals("false", StringComparison.OrdinalIgnoreCase);
             }
 
             /*
@@ -57,7 +61,8 @@ protected override string CreateManifestName
                 dependentUponFileName,
                 culture,
                 binaryStream,
-                Log
+                Log,
+                treatAsCultureNeutral
             );
         }
 
@@ -76,6 +81,7 @@ protected override string CreateManifestName
         /// <param name="culture">The override culture of this resource, if any</param>
         /// <param name="binaryStream">File contents binary stream, may be null</param>
         /// <param name="log">Task's TaskLoggingHelper, for logging warnings or errors</param>
+        /// <param name="treatAsCultureNeutral">Whether to treat the current file as 'culture-neutral' and retain the culture in the name.</param>
         /// <returns>Returns the manifest name</returns>
         internal static string CreateManifestNameImpl
         (
@@ -86,7 +92,8 @@ internal static string CreateManifestNameImpl
             string dependentUponFileName, // May be null
             string culture,
             Stream binaryStream, // File contents binary stream, may be null
-            TaskLoggingHelper log
+            TaskLoggingHelper log,
+            bool treatAsCultureNeutral = false
         )
         {
             // Use the link file name if there is one, otherwise, fall back to file name.
@@ -96,7 +103,7 @@ TaskLoggingHelper log
                 embeddedFileName = fileName;
             }
 
-            Culture.ItemCultureInfo info = Culture.GetItemCultureInfo(embeddedFileName, dependentUponFileName);
+            Culture.ItemCultureInfo info = Culture.GetItemCultureInfo(embeddedFileName, dependentUponFileName, treatAsCultureNeutral);
 
             // If the item has a culture override, respect that. 
             if (!string.IsNullOrEmpty(culture))

src/Tasks/Culture.cs

@@ -29,7 +29,8 @@ internal struct ItemCultureInfo
         internal static ItemCultureInfo GetItemCultureInfo
         (
             string name,
-            string dependentUponFilename
+            string dependentUponFilename,
+            bool treatAsCultureNeutral = false
         )
         {
             ItemCultureInfo info;
@@ -38,9 +39,11 @@ string dependentUponFilename
 
             if (String.Equals(Path.GetFileNameWithoutExtension(parentName),
                                    Path.GetFileNameWithoutExtension(name),
-                                   StringComparison.OrdinalIgnoreCase))
+                                   StringComparison.OrdinalIgnoreCase) ||
+                                   treatAsCultureNeutral)
             {
-                // Dependent, but we treat it is as not localized because they have same base filename
+                // Dependent but we treat it is as not localized because they have same base filename
+                // Or we want to treat this as a 'culture-neutral' file and retain the culture in the name. https://github.com/dotnet/msbuild/pull/5824
                 info.cultureNeutralFilename = name;
             }
             else