Merge pull request #6530 from mikkelbu/gracefully-report-invalid-projects

Gracefully report invalid project when added via sln-add

src/dotnet/CommonLocalizableStrings.cs

@@ -101,6 +101,7 @@ namespace Microsoft.DotNet.Tools
         public const string MoreThanOneProjectInDirectory = "Found more than one project in `{0}`. Please specify which one to use.";
         public const string FoundInvalidProject = "Found a project `{0}` but it is invalid.";
         public const string InvalidProject = "Invalid project `{0}`.";
+        public const string InvalidProjectWithExceptionMessage = "Invalid project `{0}`. {1}";
 
         /// Solution
         public const string CouldNotFindSolutionIn = "Specified solution file {0} does not exist, or there is no solution file in the directory.";

src/dotnet/SlnFileExtensions.cs

@@ -3,6 +3,7 @@
 
 using Microsoft.Build.Construction;
 using Microsoft.Build.Evaluation;
+using Microsoft.Build.Exceptions;
 using Microsoft.Build.Execution;
 using Microsoft.DotNet.Cli.Sln.Internal;
 using Microsoft.DotNet.Cli.Utils;
@@ -36,7 +37,19 @@ namespace Microsoft.DotNet.Tools.Common
             }
             else
             {
-                var projectInstance = new ProjectInstance(fullProjectPath);
+                ProjectInstance projectInstance = null;
+                try
+                {
+                    projectInstance = new ProjectInstance(fullProjectPath);
+                }
+                catch (InvalidProjectFileException e)
+                {
+                    Reporter.Error.WriteLine(string.Format(
+                        CommonLocalizableStrings.InvalidProjectWithExceptionMessage,
+                        fullProjectPath,
+                        e.Message));
+                    return;
+                }
 
                 var slnProject = new SlnProject
                 {

test/dotnet-sln-add.Tests/GivenDotnetSlnAdd.cs

@@ -480,6 +480,35 @@ EndGlobal
             cmd.StdErr.Should().BeEmpty();
         }
 
+        [Theory]
+        [InlineData("TestAppWithSlnAndCsprojFiles")]
+        [InlineData("TestAppWithSlnAndCsprojProjectGuidFiles")]
+        [InlineData("TestAppWithEmptySln")]
+        public void WhenInvalidProjectIsPassedItDoesNotGetAdded(string testAsset)
+        {
+            var projectDirectory = TestAssets
+                .Get(testAsset)
+                .CreateInstance()
+                .WithSourceFiles()
+                .Root
+                .FullName;
+
+            var projectToAdd = "Lib/Library.cs";
+            var projectPath = Path.Combine("Lib", "Library.cs");
+            var slnFile = SlnFile.Read(Path.Combine(projectDirectory, "App.sln"));
+            var expectedNumberOfProjects = slnFile.Projects.Count();
+
+            var cmd = new DotnetCommand()
+                .WithWorkingDirectory(projectDirectory)
+                .ExecuteWithCapturedOutput($"sln App.sln add {projectToAdd}");
+            cmd.Should().Pass();
+            cmd.StdOut.Should().BeEmpty();
+            cmd.StdErr.Should().Match("Invalid project `*`. The project file could not be loaded.*");
+
+            slnFile = SlnFile.Read(Path.Combine(projectDirectory, "App.sln"));
+            slnFile.Projects.Count().Should().Be(expectedNumberOfProjects);
+        }
+
         [Theory]
         [InlineData("TestAppWithSlnAndCsprojFiles")]
         [InlineData("TestAppWithSlnAndCsprojProjectGuidFiles")]