Migrate Common.GenerateSourceLinkFile to multithreaded task model

src/SourceLink.Common.UnitTests/GenerateSourceLinkFileTests.cs

@@ -239,5 +239,26 @@ public void DoesNotRewriteContentIfFileContentIsSame()
 
             Assert.Equal(beforeWriteTime, afterWriteTime);
         }
+
+        [Fact]
+        public void WriteSourceLinkFileRejectsRelativeOutputFile()
+        {
+            var engine = new MockEngine();
+            var task = new GenerateSourceLinkFile()
+            {
+                BuildEngine = engine,
+                // OutputFile must be fully qualified: file access must not depend on the shared process
+                // current directory under the multithreaded task model, so a relative path is rejected.
+                OutputFile = "sourcelink.json",
+                SourceRoots = new[]
+                {
+                    new MockItem(@"/_/", KVP("SourceLinkUrl", "https://raw.githubusercontent.com/repo/*"), KVP("SourceControl", "git")),
+                },
+            };
+
+            Assert.False(task.Execute());
+            Assert.Null(task.SourceLink);
+            Assert.Contains("ERROR", engine.Log);
+        }
     }
 }

src/SourceLink.Common/GenerateSourceLinkFile.cs

@@ -13,6 +13,7 @@
 
 namespace Microsoft.SourceLink.Common
 {
+    [MSBuildMultiThreadableTask]
     public sealed class GenerateSourceLinkFile : Task
     {
         [Required, NotNull]
@@ -114,6 +115,14 @@ private void WriteSourceLinkFile(string? content)
 
             try
             {
+                // OutputFile is required to be a fully qualified path. It is set by the SourceLink targets from
+                // _SourceLinkFilePath, so file access must not (and does not need to) depend on the shared process
+                // current directory under the multithreaded task model. Reject a path that isn't fully qualified.
+                if (string.IsNullOrEmpty(OutputFile) || !PathUtilities.IsPathFullyQualified(OutputFile))
+                {
+                    throw new ArgumentException($"The path '{OutputFile}' must be fully qualified.", nameof(OutputFile));
+                }
+
                 if (File.Exists(OutputFile))
                 {
                     if (content == null)

src/SourceLink.Common/build/Microsoft.SourceLink.Common.targets

@@ -6,7 +6,12 @@
 
   <Target Name="_SetSourceLinkFilePath">
     <PropertyGroup>
-      <_SourceLinkFilePath>$(IntermediateOutputPath)$(MSBuildProjectName).sourcelink.json</_SourceLinkFilePath>
+      <!--
+        All source link tasks require absolute paths so that file access does not depend on the process
+        current directory (which is not reliable under the multithreaded task model). IntermediateOutputPath
+        is typically relative to the project directory, so make _SourceLinkFilePath absolute here.
+      -->
+      <_SourceLinkFilePath>$([MSBuild]::NormalizePath('$(MSBuildProjectDirectory)', '$(IntermediateOutputPath)', '$(MSBuildProjectName).sourcelink.json'))</_SourceLinkFilePath>
     </PropertyGroup>
   </Target>
 

src/SourceLink.Git.IntegrationTests/AzureDevOpsServerTests.cs

@@ -54,7 +54,7 @@ public void FullValidation_Https()
                     ProjectSourceRoot,
                     $"https://tfs.{TestStrings.DomainName}.local:8080/tfs/DefaultCollection/project/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://tfs.{TestStrings.DomainName}.local:8080/tfs/DefaultCollection/project/_git/{repoName}",
                     $"https://tfs.{TestStrings.DomainName}.local:8080/tfs/DefaultCollection/project/_git/{repoName}",
                 });
@@ -114,7 +114,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://tfs.{TestStrings.DomainName}.local/tfs/DefaultCollection/project/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://tfs.{TestStrings.DomainName}.local/tfs/DefaultCollection/project/_git/{repoName}",
                     $"https://tfs.{TestStrings.DomainName}.local/tfs/DefaultCollection/project/_git/{repoName}",
                 });

src/SourceLink.Git.IntegrationTests/AzureReposTests.cs

@@ -54,7 +54,7 @@ public void FullValidation_Https(string host)
                     ProjectSourceRoot,
                     $"https://test.{host}/test-org/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://test.{host}/test-org/_git/{repoName}",
                     $"https://test.{host}/test-org/_git/{repoName}",
                 });
@@ -113,7 +113,7 @@ public void FullValidation_Ssh(string host)
                     ProjectSourceRoot,
                     $"https://test.{host}/test-org/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://test.{host}/test-org/_git/{repoName}",
                     $"https://test.{host}/test-org/_git/{repoName}",
                 });

src/SourceLink.Git.IntegrationTests/BitbucketGitTests.cs

@@ -50,7 +50,7 @@ public void FullValidation_CloudHttps()
                     ProjectSourceRoot,
                     $"https://api.bitbucket.org/2.0/repositories/test-org/{repoName}/src/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://bitbucket.org/test-org/{repoName}",
                     $"https://bitbucket.org/test-org/{repoName}"
                 });
@@ -111,7 +111,7 @@ public void FullValidation_EnterpriseNewHttps()
                     ProjectSourceRoot,
                     $"https://bitbucket.domain.com/projects/test-org/repos/{repoName}/raw/*?at={commitSha}",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}",
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}"
                 });
@@ -170,7 +170,7 @@ public void FullValidation_EnterpriseNewHttps_UrlWithPersonalToken()
                     ProjectSourceRoot,
                     $"https://bitbucket.domain.com/projects/test-org/repos/{repoName}/raw/*?at={commitSha}",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}.git",
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}.git"
                 });
@@ -229,7 +229,7 @@ public void FullValidation_EnterpriseNewHttpsWithDefaultFlags()
                     NuGetPackageFolders,
                     ProjectSourceRoot,
                     $"https://bitbucket.domain.com/projects/test-org/repos/{repoName}/raw/*?at={commitSha}",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}",
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}"
                 });
@@ -289,7 +289,7 @@ public void FullValidation_EnterpriseOldHttps()
                     ProjectSourceRoot,
                     $"https://bitbucket.domain.com/projects/test-org/repos/{repoName}/browse/*?at={commitSha}&raw",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}",
                     $"https://bitbucket.domain.com/scm/test-org/{repoName}"
                 });
@@ -349,7 +349,7 @@ public void FullValidation_CloudSsh()
                     ProjectSourceRoot,
                     $"https://api.{TestStrings.DomainName}.com/2.0/repositories/test-org/{repoName}/src/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });
@@ -409,7 +409,7 @@ public void FullValidation_EnterpriseOldSsh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/projects/test-org/repos/{repoName}/browse/*?at={commitSha}&raw",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });
@@ -469,7 +469,7 @@ public void FullValidation_EnterpriseNewSsh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/projects/test-org/repos/{repoName}/raw/*?at={commitSha}",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });

src/SourceLink.Git.IntegrationTests/CloudHostedProvidersTests.cs

@@ -301,10 +301,10 @@ public void CustomTranslation()
                     ProjectSourceRoot,
                     $"https://raw.githubusercontent.com/test-org/{repoName}/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://github.com/test-org/{repoName}",
                     $"https://github.com/test-org/{repoName}",
-                    s_relativeSourceLinkJsonPath
+                    SourceLinkFilePath
                 });
 
             AssertEx.AreEqual(
@@ -361,7 +361,7 @@ public void Host_VisualStudio(string host)
                     ProjectSourceRoot,
                     $"https://test.{host}/test-org/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://test.{host}/test-org/_git/{repoName}",
                     $"https://test.{host}/test-org/_git/{repoName}",
                 });
@@ -405,7 +405,7 @@ public void Host_DevAzureCom(string host)
                     ProjectSourceRoot,
                     $"https://{host}/test/test-org/_apis/git/repositories/{repoName}/items?api-version=1.0&versionType=commit&version={commitSha}&path=/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{host}/test/test-org/_git/{repoName}",
                     $"https://{host}/test/test-org/_git/{repoName}",
                 });

src/SourceLink.Git.IntegrationTests/GitHubTests.cs

@@ -68,7 +68,7 @@ public void MutlipleProjects()
                     SourceRoot,
                     $"https://raw.githubusercontent.com/test-org/test-repo2/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"http://github.com/test-org/test-repo2",
                 },
                 // the second project should reuse the repository info cached by the first project:
@@ -216,7 +216,7 @@ public void FullValidation_Https()
                     ProjectSourceRoot,
                     $"https://raw.githubusercontent.com/test-org/{repoName}/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"http://github.com/test-org/{repoName}",
                     $"http://github.com/test-org/{repoName}"
                 });
@@ -274,7 +274,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://raw.githubusercontent.com/test-org/{repoName}/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://github.com/test-org/{repoName}",
                     $"https://github.com/test-org/{repoName}"
                 });

src/SourceLink.Git.IntegrationTests/GitLabTests.cs

@@ -54,7 +54,7 @@ public void FullValidation_Https()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/-/raw/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });
@@ -114,7 +114,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/-/raw/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });

src/SourceLink.Git.IntegrationTests/GitWebTests.cs

@@ -57,7 +57,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/gitweb/?p={repoName};a=blob_plain;hb={commitSha};f=*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"ssh://git@{TestStrings.DomainName}.com/{repoNameFullyEscaped}",
                     $"ssh://git@{TestStrings.DomainName}.com/{repoNameFullyEscaped}"
                 });

src/SourceLink.Git.IntegrationTests/GiteaTests.cs

@@ -54,7 +54,7 @@ public void FullValidation_Https()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/raw/commit/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });
@@ -114,7 +114,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/raw/commit/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });

src/SourceLink.Git.IntegrationTests/GiteeTests.cs

@@ -54,7 +54,7 @@ public void FullValidation_Https()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/raw/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });
@@ -114,7 +114,7 @@ public void FullValidation_Ssh()
                     ProjectSourceRoot,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}/raw/{commitSha}/*",
                     "refs/heads/main",
-                    s_relativeSourceLinkJsonPath,
+                    SourceLinkFilePath,
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}",
                     $"https://{TestStrings.DomainName}.com/test-org/{repoName}"
                 });

src/TestUtilities/DotNetSdk/DotNetSdkTestBase.cs

@@ -75,6 +75,10 @@ private static string GetLocalNuGetConfigContent(string packagesDir) =>
         protected readonly string DotNetPath;
         protected readonly Dictionary<string, string> EnvironmentVariables;
 
+        // Absolute path of the generated source link file. The source link targets pass an absolute OutputFile
+        // to the GenerateSourceLinkFile task, so $(SourceLink) (and the corresponding FileWrites item) is absolute.
+        protected readonly string SourceLinkFilePath;
+
         protected static readonly string s_relativeSourceLinkJsonPath = Path.Combine("obj", "Debug", "netstandard2.0", "test.sourcelink.json");
         protected static readonly string s_relativeOutputFilePath = Path.Combine("obj", "Debug", "netstandard2.0", "test.dll");
         protected static readonly string s_relativePackagePath = Path.Combine("bin", "Debug", "test.1.0.0.nupkg");
@@ -213,6 +217,8 @@ public DotNetSdkTestBase(params string[] packages)
 
             Project = ProjectDir.CreateFile(ProjectFileName).WriteAllText(s_projectSource);
             ProjectDir.CreateFile("TestClass.cs").WriteAllText(s_classSource);
+
+            SourceLinkFilePath = Path.Combine(ProjectDir.Path, s_relativeSourceLinkJsonPath);
         }
 
         public static string EnsureTrailingDirectorySeparator(string path)