Merge pull request #6525 from dsplaisted/tool-tfm-fallback

Fall back to tools restored for .NET Core 1.x if they haven't been restored for .NET Core 2.0

src/Microsoft.DotNet.Cli.Utils/CommandResolution/ProjectToolsCommandResolver.cs

@@ -134,12 +134,35 @@ namespace Microsoft.DotNet.Cli.Utils
                 ProjectToolsCommandResolverName,
                 string.Join(Environment.NewLine, possiblePackageRoots.Select((p) => $"- {p}"))));
 
-            var toolPackageFramework = project.DotnetCliToolTargetFramework;
+            List<NuGetFramework> toolFrameworksToCheck = new List<NuGetFramework>();
+            toolFrameworksToCheck.Add(project.DotnetCliToolTargetFramework);
 
-            var toolLockFile = GetToolLockFile(
+            //  NuGet restore in Visual Studio may restore for netcoreapp1.0.  So if that happens, fall back to
-                toolLibraryRange,
+            //  looking for a netcoreapp1.0 or netcoreapp1.1 tool restore.
-                toolPackageFramework,
+            if (project.DotnetCliToolTargetFramework.Framework == FrameworkConstants.FrameworkIdentifiers.NetCoreApp &&
-                possiblePackageRoots);
+                project.DotnetCliToolTargetFramework.Version >= new Version(2, 0, 0))
+            {
+                toolFrameworksToCheck.Add(NuGetFramework.Parse("netcoreapp1.1"));
+                toolFrameworksToCheck.Add(NuGetFramework.Parse("netcoreapp1.0"));
+            }
+
+            
+            LockFile toolLockFile = null;
+            NuGetFramework toolTargetFramework = null; ;
+
+            foreach (var toolFramework in toolFrameworksToCheck)
+            {
+                toolLockFile = GetToolLockFile(
+                    toolLibraryRange,
+                    toolFramework,
+                    possiblePackageRoots);
+
+                if (toolLockFile != null)
+                {
+                    toolTargetFramework = toolFramework;
+                    break;
+                }
+            }
 
             if (toolLockFile == null)
             {
@@ -152,7 +175,7 @@ namespace Microsoft.DotNet.Cli.Utils
                 toolLockFile.Path));
 
             var toolLibrary = toolLockFile.Targets
-                .FirstOrDefault(t => toolPackageFramework == t.TargetFramework)
+                .FirstOrDefault(t => toolTargetFramework == t.TargetFramework)
                 ?.Libraries.FirstOrDefault(
                     l => StringComparer.OrdinalIgnoreCase.Equals(l.Name, toolLibraryRange.Name));
             if (toolLibrary == null)
@@ -168,7 +191,7 @@ namespace Microsoft.DotNet.Cli.Utils
 
             var depsFilePath = GetToolDepsFilePath(
                 toolLibraryRange,
-                toolPackageFramework,
+                toolTargetFramework,
                 toolLockFile,
                 depsFileRoot,
                 project.ToolDepsJsonGeneratorProject);

test/dotnet.Tests/PackagedCommandTests.cs

@@ -16,6 +16,7 @@ using Xunit.Abstractions;
 using Microsoft.Build.Construction;
 using System.Linq;
 using Microsoft.Build.Evaluation;
+using System.Xml.Linq;
 
 namespace Microsoft.DotNet.Tests
 {
@@ -161,10 +162,62 @@ namespace Microsoft.DotNet.Tests
                 .Execute(toolPrefersCLIRuntime ? "portable-v1-prefercli" : "portable-v1");
 
             result.Should().Pass()
-                .And.HaveStdOutContaining("I'm running on shared framework version 1.1.1!");    
+                .And.HaveStdOutContaining("I'm running on shared framework version 1.1.1!");
 
         }
 
+        [RequiresSpecificFrameworkFact("netcoreapp1.1")]
+        public void IfAToolHasNotBeenRestoredForNetCoreApp2_0ItFallsBackToNetCoreApp1_x()
+        {
+            string toolName = "dotnet-portable-v1";
+
+            var toolFolder = Path.Combine(new RepoDirectoriesProvider().NugetPackages,
+                                          ".tools",
+                                          toolName);
+
+            //  Other tests may have restored the tool for netcoreapp2.0, so delete its tools folder
+            if (Directory.Exists(toolFolder))
+            {
+                Directory.Delete(toolFolder, true);
+            }
+
+            var testInstance = TestAssets.Get("AppWithToolDependency")
+                .CreateInstance()
+                .WithSourceFiles()
+                .WithNuGetConfig(new RepoDirectoriesProvider().TestPackages);
+
+            testInstance = testInstance.WithProjectChanges(project =>
+            {
+                var ns = project.Root.Name.Namespace;
+
+                //  Remove reference to tool that won't restore on 1.x
+                project.Descendants(ns + "DotNetCliToolReference")
+                    .Where(tr => tr.Attribute("Include").Value == "dotnet-PreferCliRuntime")
+                    .Remove();
+
+                var toolReference = project.Descendants(ns + "DotNetCliToolReference")
+                    .Where(tr => tr.Attribute("Include").Value == "dotnet-portable")
+                    .Single();
+
+                toolReference.Attribute("Include").Value = toolName;
+
+                //  Restore tools for .NET Core 1.1
+                project.Root.Element(ns + "PropertyGroup")
+                    .Add(new XElement(ns + "DotnetCliToolTargetFramework", "netcoreapp1.1"));
+
+            });
+
+            testInstance = testInstance.WithRestoreFiles();
+
+            var result =
+                    new DotnetCommand(DotnetUnderTest.WithBackwardsCompatibleRuntimes)
+                    .WithWorkingDirectory(testInstance.Root)
+                    .Execute("portable-v1");
+
+            result.Should().Pass()
+                .And.HaveStdOutContaining("I'm running on shared framework version 1.1.1!");
+        }
+
         [Fact]
         public void CanInvokeToolWhosePackageNameIsDifferentFromDllName()
         {