VB-specific DocumentationFile generation.

src/Assets/TestProjects/AppWithLibraryVB/TestApp/Program.vb

@@ -0,0 +1,16 @@
+' Copyright (c) .NET Foundation and contributors. All rights reserved.
+' Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+Imports System
+
+Namespace TestApp
+
+    Module Program
+
+        Sub Main(args As String())
+            Console.WriteLine(TestLibrary.Helper.GetMessage())
+        End Sub
+
+    End Module
+
+End Namespace

src/Assets/TestProjects/AppWithLibraryVB/TestApp/TestApp.vbproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <Version>1.2.3-beta</Version>
+    <Authors>Test Authors</Authors>
+    <Product>Test Product</Product>
+    <AssemblyTitle>Test AssemblyTitle</AssemblyTitle>
+    <Copyright>Copyright (c) Test Authors</Copyright>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp1.1</TargetFramework>
+  </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="../TestLibrary/TestLibrary.vbproj" />
+  </ItemGroup>
+</Project>

src/Assets/TestProjects/AppWithLibraryVB/TestLibrary/Helper.vb

@@ -0,0 +1,18 @@
+' Copyright (c) .NET Foundation and contributors. All rights reserved.
+' Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+Namespace TestLibrary
+
+    Public Class Helper
+
+        Public Shared Function GetMessage() As String
+            Return "This string came from the test library!"
+        End Function
+
+        Public Sub SayHi()
+            Console.WriteLine("Hello there!")
+        End Sub
+
+    End Class
+
+End Namespace

src/Assets/TestProjects/AppWithLibraryVB/TestLibrary/TestLibrary.vbproj

@@ -0,0 +1,7 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <Version>42.43.44.45-alpha</Version>
+    <OutputType>Library</OutputType>
+    <TargetFramework>netstandard1.5</TargetFramework>
+  </PropertyGroup>
+</Project>

src/Tasks/Microsoft.NET.Build.Tasks/build/Microsoft.NET.Sdk.BeforeCommon.targets

@@ -165,7 +165,8 @@ Copyright (c) .NET Foundation. All rights reserved.
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(GenerateDocumentationFile)' == 'true' and '$(DocumentationFile)' == ''">
-    <DocumentationFile>$(IntermediateOutputPath)$(AssemblyName).xml</DocumentationFile>
+    <DocumentationFile Condition="'$(MSBuildProjectExtension)' == '.vbproj'">$(AssemblyName).xml</DocumentationFile>
+    <DocumentationFile Condition="'$(MSBuildProjectExtension)' != '.vbproj'">$(IntermediateOutputPath)$(AssemblyName).xml</DocumentationFile>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(GenerateDocumentationFile)' != 'true'">

src/Tests/Microsoft.NET.Build.Tests/GivenThatWeWantToBuildALibrary.cs

@@ -203,14 +203,20 @@ internal static List<string> GetValuesFromTestLibrary(
             return itemValues;
         }
 
-        private TestAsset CreateDocumentationFileLibraryAsset(bool? generateDocumentationFile, string documentationFile, [CallerMemberName] string callingMethod = "")
+        private TestAsset CreateDocumentationFileLibraryAsset(bool? generateDocumentationFile, string documentationFile, string language, [CallerMemberName] string callingMethod = "")
         {
             string genDocFileIdentifier = generateDocumentationFile == null ? "null" : generateDocumentationFile.Value.ToString();
             string docFileIdentifier = documentationFile == null ? "null" : Path.GetFileName(documentationFile);
             string identifier = $"-genDoc={genDocFileIdentifier}, docFile={Path.GetFileName(docFileIdentifier)}";
 
+            var testAssetName = "AppWithLibrary";
+            if (language != "cs")
+            {
+                testAssetName += language.ToUpperInvariant();
+            }
+
             var testAsset = _testAssetsManager
-                .CopyTestAsset("AppWithLibrary", callingMethod, identifier)
+                .CopyTestAsset(testAssetName, callingMethod, identifier)
                 .WithSource()
                 .WithProjectChanges(project =>
                 {
@@ -232,10 +238,12 @@ private TestAsset CreateDocumentationFileLibraryAsset(bool? generateDocumentatio
             return testAsset;
         }
 
-        [Fact]
-        public void It_creates_a_documentation_file()
+        [Theory]
+        [InlineData("cs")]
+        [InlineData("vb")]
+        public void It_creates_a_documentation_file(string language)
         {
-            var testAsset = CreateDocumentationFileLibraryAsset(true, null);
+            var testAsset = CreateDocumentationFileLibraryAsset(true, null, language);
 
             var libraryProjectDirectory = Path.Combine(testAsset.TestRoot, "TestLibrary");
 
@@ -257,17 +265,19 @@ public void It_creates_a_documentation_file()
 
             new DirectoryInfo(libraryProjectDirectory).Should().OnlyHaveFiles(new[]
             {
-                "Helper.cs",
-                "TestLibrary.csproj"
+                $"Helper.{language}",
+                $"TestLibrary.{language}proj"
             }, SearchOption.TopDirectoryOnly);
         }
 
         [Theory]
-        [InlineData(true)]
-        [InlineData(false)]
-        public void It_allows_us_to_override_the_documentation_file_name(bool setGenerateDocumentationFileProperty)
+        [InlineData("cs", true)]
+        [InlineData("cs", false)]
+        [InlineData("vb", true)]
+        [InlineData("vb", false)]
+        public void It_allows_us_to_override_the_documentation_file_name(string language, bool setGenerateDocumentationFileProperty)
         {
-            var testAsset = CreateDocumentationFileLibraryAsset(setGenerateDocumentationFileProperty ? (bool?)true : null, "TestLibDoc.xml", "OverrideDocFileName");
+            var testAsset = CreateDocumentationFileLibraryAsset(setGenerateDocumentationFileProperty ? (bool?)true : null, "TestLibDoc.xml", language,  "OverrideDocFileName");
 
             var libraryProjectDirectory = Path.Combine(testAsset.TestRoot, "TestLibrary");
 
@@ -289,20 +299,28 @@ public void It_allows_us_to_override_the_documentation_file_name(bool setGenerat
 
             //  Due to the way the DocumentationFile works, if you specify an unrooted filename, then the documentation file will be generated in that
             //  location relative to the project folder, and then copied to the output folder.
-            new DirectoryInfo(libraryProjectDirectory).Should().OnlyHaveFiles(new[]
+            var expectedProjectDirectoryFiles = new List<string>()
             {
-                "Helper.cs",
-                "TestLibrary.csproj",
-                "TestLibDoc.xml"
-            }, SearchOption.TopDirectoryOnly);
+                $"Helper.{language}",
+                $"TestLibrary.{language}proj"
+            };
+
+            // vb uses DocumentationFile relative to the IntermediateOutputPath
+            if (language != "vb") {
+                expectedProjectDirectoryFiles.Add("TestLibDoc.xml");
+            }
+
+            new DirectoryInfo(libraryProjectDirectory).Should().OnlyHaveFiles(expectedProjectDirectoryFiles, SearchOption.TopDirectoryOnly);
         }
 
         [Theory]
-        [InlineData(true)]
-        [InlineData(false)]
-        public void It_does_not_create_a_documentation_file_if_GenerateDocumentationFile_property_is_false(bool setDocumentationFileProperty)
+        [InlineData("cs", true)]
+        [InlineData("cs", false)]
+        [InlineData("vb", true)]
+        [InlineData("vb", false)]
+        public void It_does_not_create_a_documentation_file_if_GenerateDocumentationFile_property_is_false(string language, bool setDocumentationFileProperty)
         {
-            var testAsset = CreateDocumentationFileLibraryAsset(false, setDocumentationFileProperty ? "TestLibDoc.xml" : null, "DoesntCreateDocFile");
+            var testAsset = CreateDocumentationFileLibraryAsset(false, setDocumentationFileProperty ? "TestLibDoc.xml" : null, language, "DoesntCreateDocFile");
 
             var libraryProjectDirectory = Path.Combine(testAsset.TestRoot, "TestLibrary");
 
@@ -324,8 +342,8 @@ public void It_does_not_create_a_documentation_file_if_GenerateDocumentationFile
             //  Make sure documentation file isn't generated in project folder either
             new DirectoryInfo(libraryProjectDirectory).Should().OnlyHaveFiles(new[]
             {
-                "Helper.cs",
-                "TestLibrary.csproj"
+                $"Helper.{language}",
+                $"TestLibrary.{language}proj"
             }, SearchOption.TopDirectoryOnly);
         }
 

src/Tests/Microsoft.NET.TestFramework/Commands/MSBuildCommand.cs

@@ -51,11 +51,11 @@ internal static string FindProjectFile(ref string projectRootPath, string relati
                 }
             }
 
-            var buildProjectFiles = Directory.GetFiles(projectRootPath, "*.csproj");
+            var buildProjectFiles = Directory.GetFiles(projectRootPath, "*.*proj");
 
             if (buildProjectFiles.Length != 1)
             {
-                var errorMsg = $"Found {buildProjectFiles.Length} .csproj files under {projectRootPath} instead of just 1.";
+                var errorMsg = $"Found {buildProjectFiles.Length} project files under {projectRootPath} instead of just 1.";
                 throw new ArgumentException(errorMsg);
             }