feat: add dollar-self action reference syntax (#4457)

images/Dockerfile

@@ -5,7 +5,7 @@ ARG TARGETOS
 ARG TARGETARCH
 ARG RUNNER_VERSION
 ARG RUNNER_CONTAINER_HOOKS_VERSION=0.7.0
-ARG DOCKER_VERSION=29.6.0
+ARG DOCKER_VERSION=29.6.1
 ARG BUILDX_VERSION=0.35.0
 
 RUN apt update -y && apt install curl unzip -y

src/Runner.Common/Constants.cs

@@ -180,6 +180,7 @@ namespace GitHub.Runner.Common
                 public static readonly string BatchActionResolution = "actions_batch_action_resolution";
                 public static readonly string UseBearerTokenForCodeload = "actions_use_bearer_token_for_codeload";
                 public static readonly string OverrideDebuggerWelcomeMessage = "actions_runner_override_debugger_welcome_message";
+                public static readonly string SelfRepository = "actions_self_repository";
             }
 
             // Node version migration related constants

src/Runner.Worker/ActionManager.cs

@@ -178,7 +178,7 @@ namespace GitHub.Runner.Worker
             return new PrepareResult(containerSetupSteps, result.PreStepTracker);
         }
 
-        private async Task<PrepareActionsState> PrepareActionsRecursiveAsync(IExecutionContext executionContext, PrepareActionsState state, IEnumerable<Pipelines.ActionStep> actions, Dictionary<string, WebApi.ActionDownloadInfo> resolvedDownloadInfos, Int32 depth = 0, Guid parentStepId = default(Guid))
+        private async Task<PrepareActionsState> PrepareActionsRecursiveAsync(IExecutionContext executionContext, PrepareActionsState state, IEnumerable<Pipelines.ActionStep> actions, Dictionary<string, WebApi.ActionDownloadInfo> resolvedDownloadInfos, Int32 depth = 0, Guid parentStepId = default(Guid), string selfRepoName = null, string selfRepoRef = null)
         {
             ArgUtil.NotNull(executionContext, nameof(executionContext));
             if (depth > Constants.CompositeActionsMaxDepth)
@@ -186,6 +186,21 @@ namespace GitHub.Runner.Worker
                 throw new Exception($"Composite action depth exceeded max depth {Constants.CompositeActionsMaxDepth}");
             }
 
+            // Resolve self-repository ($/) references before processing
+            if (executionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SelfRepository) == true)
+            {
+                if (string.IsNullOrEmpty(selfRepoName))
+                {
+                    // job.workflow_repository/workflow_sha point to the repo
+                    // containing the workflow file — correct for both regular
+                    // and reusable workflows. Always present when the server
+                    // supports $/. See: https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/accessing-contextual-information-about-workflow-runs#github-context
+                    selfRepoName = executionContext.JobContext?.WorkflowRepository;
+                    selfRepoRef = executionContext.JobContext?.WorkflowSha;
+                }
+                ResolveSelfRepositoryReferences(executionContext, actions, selfRepoName, selfRepoRef);
+            }
+
             var repositoryActions = new List<Pipelines.ActionStep>();
 
             foreach (var action in actions)
@@ -301,16 +316,53 @@ namespace GitHub.Runner.Worker
                 // then recurse per parent (which hits the cache, not the API).
                 if (nextLevel.Count > 0)
                 {
-                    var nextLevelRepoActions = nextLevel
-                        .Where(x => x.action.Reference.Type == Pipelines.ActionSourceType.Repository)
-                        .Select(x => x.action)
-                        .ToList();
-                    await ResolveNewActionsAsync(executionContext, nextLevelRepoActions, resolvedDownloadInfos);
-
-                    foreach (var group in nextLevel.GroupBy(x => x.parentId))
+                    if (executionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SelfRepository) == true)
                     {
-                        var groupActions = group.Select(x => x.action).ToList();
-                        state = await PrepareActionsRecursiveAsync(executionContext, state, groupActions, resolvedDownloadInfos, depth + 1, group.Key);
+                        // Self-repository path: group by parent so each group's
+                        // $/ refs resolve against the correct parent repo context.
+                        var groups = nextLevel.GroupBy(x => x.parentId).Select(group =>
+                        {
+                            string childRepoName = selfRepoName;
+                            string childRepoRef = selfRepoRef;
+                            var parentAction = repositoryActions.FirstOrDefault(a => a.Id == group.Key);
+                            if (parentAction?.Reference is Pipelines.RepositoryPathReference parentRef &&
+                                string.Equals(parentRef.RepositoryType, Pipelines.RepositoryTypes.GitHub, StringComparison.OrdinalIgnoreCase))
+                            {
+                                childRepoName = parentRef.Name;
+                                childRepoRef = parentRef.Ref;
+                            }
+                            return new { ParentId = group.Key, Actions = group.Select(x => x.action).ToList(), RepoName = childRepoName, RepoRef = childRepoRef };
+                        }).ToList();
+
+                        foreach (var group in groups)
+                        {
+                            ResolveSelfRepositoryReferences(executionContext, group.Actions, group.RepoName, group.RepoRef);
+                        }
+
+                        var nextLevelRepoActions = nextLevel
+                            .Where(x => x.action.Reference.Type == Pipelines.ActionSourceType.Repository)
+                            .Select(x => x.action)
+                            .ToList();
+                        await ResolveNewActionsAsync(executionContext, nextLevelRepoActions, resolvedDownloadInfos);
+
+                        foreach (var group in groups)
+                        {
+                            state = await PrepareActionsRecursiveAsync(executionContext, state, group.Actions, resolvedDownloadInfos, depth + 1, group.ParentId, group.RepoName, group.RepoRef);
+                        }
+                    }
+                    else
+                    {
+                        // Original path: no self-repository resolution needed.
+                        var nextLevelActions = nextLevel.Select(x => x.action).ToList();
+                        var nextLevelRepoActions = nextLevelActions
+                            .Where(x => x.Reference.Type == Pipelines.ActionSourceType.Repository)
+                            .ToList();
+                        await ResolveNewActionsAsync(executionContext, nextLevelRepoActions, resolvedDownloadInfos);
+
+                        foreach (var grp in nextLevel.GroupBy(x => x.parentId))
+                        {
+                            state = await PrepareActionsRecursiveAsync(executionContext, state, grp.Select(x => x.action).ToList(), resolvedDownloadInfos, depth + 1, grp.Key);
+                        }
                     }
                 }
 
@@ -386,13 +438,25 @@ namespace GitHub.Runner.Worker
         /// sub-actions individually, with no cross-depth deduplication.
         /// Used when the BatchActionResolution feature flag is disabled.
         /// </summary>
-        private async Task<PrepareActionsState> PrepareActionsRecursiveLegacyAsync(IExecutionContext executionContext, PrepareActionsState state, IEnumerable<Pipelines.ActionStep> actions, Int32 depth = 0, Guid parentStepId = default(Guid))
+        private async Task<PrepareActionsState> PrepareActionsRecursiveLegacyAsync(IExecutionContext executionContext, PrepareActionsState state, IEnumerable<Pipelines.ActionStep> actions, Int32 depth = 0, Guid parentStepId = default(Guid), string selfRepoName = null, string selfRepoRef = null)
         {
             ArgUtil.NotNull(executionContext, nameof(executionContext));
             if (depth > Constants.CompositeActionsMaxDepth)
             {
                 throw new Exception($"Composite action depth exceeded max depth {Constants.CompositeActionsMaxDepth}");
             }
+
+            // Resolve self-repository ($/) references before processing
+            if (executionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SelfRepository) == true)
+            {
+                if (string.IsNullOrEmpty(selfRepoName))
+                {
+                    selfRepoName = executionContext.JobContext?.WorkflowRepository;
+                    selfRepoRef = executionContext.JobContext?.WorkflowSha;
+                }
+                ResolveSelfRepositoryReferences(executionContext, actions, selfRepoName, selfRepoRef);
+            }
+
             var repositoryActions = new List<Pipelines.ActionStep>();
 
             foreach (var action in actions)
@@ -517,7 +581,17 @@ namespace GitHub.Runner.Worker
                     }
                     else if (setupInfo != null && setupInfo.Steps != null && setupInfo.Steps.Count > 0)
                     {
-                        state = await PrepareActionsRecursiveLegacyAsync(executionContext, state, setupInfo.Steps, depth + 1, action.Id);
+                        // Propagate parent's repo context for nested self-repository resolution
+                        var parentRef = action.Reference as Pipelines.RepositoryPathReference;
+                        var childRepoName = selfRepoName;
+                        var childRepoRef = selfRepoRef;
+                        if (parentRef != null &&
+                            string.Equals(parentRef.RepositoryType, Pipelines.RepositoryTypes.GitHub, StringComparison.OrdinalIgnoreCase))
+                        {
+                            childRepoName = parentRef.Name;
+                            childRepoRef = parentRef.Ref;
+                        }
+                        state = await PrepareActionsRecursiveLegacyAsync(executionContext, state, setupInfo.Steps, depth + 1, action.Id, childRepoName, childRepoRef);
                     }
                     var repoAction = action.Reference as Pipelines.RepositoryPathReference;
                     if (repoAction.RepositoryType != Pipelines.PipelineConstants.SelfAlias)
@@ -630,6 +704,12 @@ namespace GitHub.Runner.Worker
                         actionDirectory = Path.Combine(actionDirectory, repoAction.Path);
                     }
                 }
+                else if (string.Equals(repoAction.RepositoryType, Pipelines.PipelineConstants.SelfRepositoryAlias, StringComparison.OrdinalIgnoreCase))
+                {
+                    // Unresolved self-repository reference at load time — this
+                    // shouldn't happen but guard against NRE if it does.
+                    throw new InvalidOperationException($"Self-repository reference '$/{repoAction.Path}' was not resolved before LoadAction. Ensure the '{Constants.Runner.Features.SelfRepository}' feature flag is enabled.");
+                }
                 else
                 {
                     actionDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Actions), repoAction.Name.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), repoAction.Ref);
@@ -765,6 +845,27 @@ namespace GitHub.Runner.Worker
                                 _cachedEmbeddedStepIds[action.Id].Add(guid);
                             }
                         }
+
+                        // Resolve self-repository refs in composite steps at load time.
+                        // During setup, resolution happens on a separate copy of these
+                        // step objects. At runtime, action.yml is re-parsed, producing
+                        // fresh self-repository refs that need resolution here.
+                        // When the parent is a dot-slash (self local-workspace) action,
+                        // repoAction.Name/Ref are null — fall back to workflow context.
+                        if (executionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SelfRepository) == true)
+                        {
+                            var parentName = repoAction.Name ?? executionContext.JobContext?.WorkflowRepository;
+                            var parentRef = repoAction.Ref ?? executionContext.JobContext?.WorkflowSha;
+                            ResolveSelfRepositoryReferences(executionContext, compositeAction.Steps, parentName, parentRef);
+                            if (compositeAction.PreSteps != null)
+                            {
+                                ResolveSelfRepositoryReferences(executionContext, compositeAction.PreSteps, parentName, parentRef);
+                            }
+                            if (compositeAction.PostSteps != null)
+                            {
+                                ResolveSelfRepositoryReferences(executionContext, compositeAction.PostSteps, parentName, parentRef);
+                            }
+                        }
                     }
                     else
                     {
@@ -1444,6 +1545,47 @@ namespace GitHub.Runner.Worker
             }
         }
 
+        /// <summary>
+        /// Resolves self-reference ($/) references by mutating them in-place
+        /// to standard GitHub repository references with the containing repo's
+        /// name and ref.
+        /// </summary>
+        private void ResolveSelfRepositoryReferences(IExecutionContext executionContext, IEnumerable<Pipelines.ActionStep> actions, string repoName, string repoRef)
+        {
+            if (string.IsNullOrEmpty(repoName) || string.IsNullOrEmpty(repoRef))
+            {
+                return;
+            }
+
+            foreach (var action in actions)
+            {
+                if (action.Reference.Type != Pipelines.ActionSourceType.Repository)
+                {
+                    continue;
+                }
+
+                var repoAction = action.Reference as Pipelines.RepositoryPathReference;
+                if (!string.Equals(repoAction.RepositoryType, Pipelines.PipelineConstants.SelfRepositoryAlias, StringComparison.OrdinalIgnoreCase))
+                {
+                    continue;
+                }
+
+                Trace.Info($"Resolving self-repository reference reference '$/{repoAction.Path}' to '{repoName}/{repoAction.Path}@{repoRef}'");
+                executionContext.Debug($"Resolving $/{repoAction.Path} → {repoName}/{repoAction.Path}@{repoRef}");
+
+                repoAction.RepositoryType = Pipelines.RepositoryTypes.GitHub;
+                repoAction.Name = repoName;
+                repoAction.Ref = repoRef;
+            }
+        }
+
+        /// <summary>
+        /// If this is a reusable workflow job, ensure the workflow repo tarball
+        /// is downloaded so self.workspace resolves to a real path on disk.
+        /// Always downloads for reusable workflows when the feature flag is on,
+        /// since step expressions are already expanded by the server and can't
+        /// be scanned for self.* usage.
+        /// </summary>
         private static string GetDownloadInfoLookupKey(Pipelines.ActionStep action)
         {
             if (action.Reference.Type != Pipelines.ActionSourceType.Repository)
@@ -1459,6 +1601,11 @@ namespace GitHub.Runner.Worker
                 return null;
             }
 
+            if (string.Equals(repositoryReference.RepositoryType, Pipelines.PipelineConstants.SelfRepositoryAlias, StringComparison.OrdinalIgnoreCase))
+            {
+                throw new InvalidOperationException($"Unable to resolve self-reference '$/'. This can occur when the server does not support this syntax, the feature flag is disabled, or the workflow context (repository/SHA) is unavailable.");
+            }
+
             if (!string.Equals(repositoryReference.RepositoryType, Pipelines.RepositoryTypes.GitHub, StringComparison.OrdinalIgnoreCase))
             {
                 throw new NotSupportedException(repositoryReference.RepositoryType);

src/Runner.Worker/Handlers/ContainerActionHandler.cs

@@ -239,11 +239,6 @@ namespace GitHub.Runner.Worker.Handlers
                 Environment["ACTIONS_RESULTS_URL"] = resultsUrl;
             }
 
-            if (ExecutionContext.Global.Variables.TryGetValue("actions_cache_mode", out var cacheMode) && !string.IsNullOrEmpty(cacheMode))
-            {
-                Environment["ACTIONS_CACHE_MODE"] = cacheMode;
-            }
-
             if (ExecutionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SetOrchestrationIdEnvForActions) ?? false)
             {
                 if (ExecutionContext.Global.Variables.TryGetValue(Constants.Variables.System.OrchestrationId, out var orchestrationId) && !string.IsNullOrEmpty(orchestrationId))

src/Runner.Worker/Handlers/NodeScriptActionHandler.cs

@@ -78,11 +78,6 @@ namespace GitHub.Runner.Worker.Handlers
                 Environment["ACTIONS_CACHE_SERVICE_V2"] = bool.TrueString;
             }
 
-            if (ExecutionContext.Global.Variables.TryGetValue("actions_cache_mode", out var cacheMode) && !string.IsNullOrEmpty(cacheMode))
-            {
-                Environment["ACTIONS_CACHE_MODE"] = cacheMode;
-            }
-
             if (ExecutionContext.Global.Variables.GetBoolean(Constants.Runner.Features.SetOrchestrationIdEnvForActions) ?? false)
             {
                 if (ExecutionContext.Global.Variables.TryGetValue(Constants.Variables.System.OrchestrationId, out var orchestrationId) && !string.IsNullOrEmpty(orchestrationId))

src/Runner.Worker/JobExtension.cs

@@ -171,12 +171,6 @@ namespace GitHub.Runner.Worker
                         context.Output($"Secret source: {secretSource}");
                     }
 
-                    var cacheMode = jobContext.Global.Variables.Get("actions_cache_mode");
-                    if (!string.IsNullOrEmpty(cacheMode))
-                    {
-                        context.Output($"Actions cache-mode: {cacheMode}");
-                    }
-
                     var repoFullName = context.GetGitHubContext("repository");
                     ArgUtil.NotNull(repoFullName, nameof(repoFullName));
                     context.Debug($"Primary repository: {repoFullName}");

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateConverter.cs

@@ -55,7 +55,18 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                         break;
                     case ActionSourceType.Repository:
                         var repositoryReference = step.Reference as RepositoryPathReference;
-                        name = !String.IsNullOrEmpty(repositoryReference.Name) ? repositoryReference.Name : PipelineConstants.SelfAlias;
+                        if (!String.IsNullOrEmpty(repositoryReference.Name))
+                        {
+                            name = repositoryReference.Name;
+                        }
+                        else if (String.Equals(repositoryReference.RepositoryType, PipelineConstants.SelfRepositoryAlias, StringComparison.OrdinalIgnoreCase))
+                        {
+                            name = PipelineConstants.SelfRepositoryAlias;
+                        }
+                        else
+                        {
+                            name = PipelineConstants.SelfAlias;
+                        }
                         break;
                 }
 
@@ -600,6 +611,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                         Path = uses.Value
                     };
                 }
+                else if (PipelineConstants.TryParseSelfRepository(uses.Value, out var selfPath))
+                {
+                    result.Reference = new RepositoryPathReference
+                    {
+                        RepositoryType = PipelineConstants.SelfRepositoryAlias,
+                        Path = selfPath
+                    };
+                }
                 else
                 {
                     var usesSegments = uses.Value.Split('@');

src/Sdk/DTPipelines/Pipelines/PipelineConstants.cs

@@ -38,10 +38,43 @@ namespace GitHub.DistributedTask.Pipelines
         public static readonly Int32 MaxNodeNameLength = 100;
 
         /// <summary>
-        /// Alias for the self repository.
+        /// Alias for the self local-workspace repository type (./ syntax).
+        /// Resolves to the local checkout on the runner.
         /// </summary>
         public static readonly String SelfAlias = "self";
 
+        /// <summary>
+        /// RepositoryType for self-repository references ($/ syntax).
+        /// Resolves to "this repo, at this SHA" based on the containing YAML file.
+        /// </summary>
+        public static readonly String SelfRepositoryAlias = "selfRepository";
+
+        /// <summary>
+        /// The prefix for self-repository references in uses: values.
+        /// </summary>
+        public const String SelfRepositoryPrefix = "$/";
+
+        /// <summary>
+        /// Returns true if the uses value is a self-repository reference (starts with $/),
+        /// and outputs the subpath after the prefix.
+        /// </summary>
+        public static bool TryParseSelfRepository(string usesValue, out string path)
+        {
+            if (usesValue != null && usesValue.StartsWith(SelfRepositoryPrefix, StringComparison.Ordinal))
+            {
+                path = usesValue.Substring(SelfRepositoryPrefix.Length).TrimStart('/');
+                if (string.IsNullOrEmpty(path))
+                {
+                    path = null;
+                    return false;
+                }
+                return true;
+            }
+
+            path = null;
+            return false;
+        }
+
         /// <summary>
         /// Error code during graph validation.
         /// </summary>

src/Sdk/WorkflowParser/Conversion/WorkflowTemplateConverter.cs

@@ -1605,6 +1605,10 @@ namespace GitHub.Actions.WorkflowParser.Conversion
                     {
                         id = WorkflowConstants.SelfAlias;
                     }
+                    else if (GitHub.DistributedTask.Pipelines.PipelineConstants.TryParseSelfRepository(action.Uses!.Value, out _))
+                    {
+                        id = WorkflowConstants.SelfRepositoryAlias;
+                    }
                     else
                     {
                         var usesSegments = action.Uses!.Value.Split('@');

src/Sdk/WorkflowParser/WorkflowConstants.cs

@@ -26,10 +26,15 @@ namespace GitHub.Actions.WorkflowParser
         internal const Int32 MaxNodeNameLength = 100;
 
         /// <summary>
-        /// Alias for the self repository.
+        /// Alias for the self local-workspace repository type (./ syntax).
         /// </summary>
         internal const String SelfAlias = "self";
 
+        /// <summary>
+        /// RepositoryType for self-repository references ($/ syntax).
+        /// </summary>
+        internal const String SelfRepositoryAlias = "selfRepository";
+
         public static class PermissionsPolicy
         {
             public const string LimitedRead = "LimitedRead";

src/Test/L0/Worker/ActionManagerL0.cs

@@ -585,9 +585,9 @@ runs:
 
                 //Assert
                 string destDirectory = Path.Combine(_hc.GetDirectory(WellKnownDirectory.Actions), "actions", "checkout", "master");
-                Assert.True(Directory.Exists(destDirectory), "Destination directory does not exist");  
-                var di = new DirectoryInfo(destDirectory);   
-                Assert.NotNull(di.LinkTarget); 
+                Assert.True(Directory.Exists(destDirectory), "Destination directory does not exist");
+                var di = new DirectoryInfo(destDirectory);
+                Assert.NotNull(di.LinkTarget);
             }
             finally
             {
@@ -2441,7 +2441,7 @@ runs:
             }
         }
 
-         [Fact]
+        [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
         public void LoadsNode24ActionDefinition()
@@ -2509,7 +2509,7 @@ runs:
                 Teardown();
             }
         }
-        
+
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
@@ -3533,5 +3533,604 @@ runs:
                 Teardown();
             }
         }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_ResolvesAtDepthZero()
+        {
+            // Self-references are only supported via run service (batch resolution path)
+            Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", "true");
+            try
+            {
+                // Arrange
+                Setup();
+                const string RepoName = "my-org/my-repo";
+                const string RepoSha = "abc123def456";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RepoSha);
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RepoName;
+                jobContext.WorkflowSha = RepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                var actionId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = actionId,
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "actions/my-action"
+                        }
+                    }
+                };
+
+                string archiveFile = await CreateRepoArchive();
+                using var stream = File.OpenRead(archiveFile);
+                string archiveLink = GetLinkToActionArchive("https://api.github.com", RepoName, RepoSha);
+                var mockClientHandler = new Mock<HttpClientHandler>();
+                mockClientHandler.Protected().Setup<Task<HttpResponseMessage>>("SendAsync", ItExpr.Is<HttpRequestMessage>(m => m.RequestUri == new Uri(archiveLink)), ItExpr.IsAny<CancellationToken>())
+                    .ReturnsAsync(new HttpResponseMessage(HttpStatusCode.OK) { Content = new StreamContent(stream) });
+                var mockHandlerFactory = new Mock<IHttpClientHandlerFactory>();
+                mockHandlerFactory.Setup(p => p.CreateClientHandler(It.IsAny<RunnerWebProxy>())).Returns(mockClientHandler.Object);
+                _hc.SetSingleton(mockHandlerFactory.Object);
+
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+
+                // Act — resolution mutates the reference in-place before download/prepare.
+                // The archive doesn't contain the subpath, so prepare will fail, but the
+                // reference is already resolved by that point.
+                try
+                {
+                    await _actionManager.PrepareActionsAsync(_ec.Object, actions);
+                }
+                catch (InvalidOperationException ex) when (ex.Message.Contains("Can't find"))
+                {
+                    // Expected: test archive lacks the action.yml at the resolved subpath
+                }
+
+                // Assert — the reference should be resolved to a GitHub repo reference
+                var repoRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, repoRef.RepositoryType);
+                Assert.Equal(RepoName, repoRef.Name);
+                Assert.Equal(RepoSha, repoRef.Ref);
+                Assert.Equal("actions/my-action", repoRef.Path);
+            }
+            finally
+            {
+                Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", null);
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_NotResolvedWhenFeatureFlagDisabled()
+        {
+            try
+            {
+                // Arrange
+                Setup();
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns("my-org/my-repo");
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns("abc123");
+                // Feature flag NOT set
+
+                var actionId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = actionId,
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "actions/my-action"
+                        }
+                    }
+                };
+
+                // Act & Assert — should throw because unresolved self-reference hits GetDownloadInfoLookupKey
+                await Assert.ThrowsAsync<InvalidOperationException>(async () =>
+                    await _actionManager.PrepareActionsAsync(_ec.Object, actions));
+            }
+            finally
+            {
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_ResolvesNestedInComposite()
+        {
+            // Composite action at $/actions/parent uses $/actions/child (same repo).
+            // This tests the batch path fix: $/ refs in nextLevel must be resolved
+            // BEFORE ResolveNewActionsAsync, otherwise GetDownloadInfoLookupKey throws.
+            // We pre-stage only the parent action.yml on disk so the composite steps
+            // are discovered, but we DON'T stage the child — a download failure for
+            // the child is fine; the important thing is that $/ was resolved
+            // (no InvalidOperationException from GetDownloadInfoLookupKey).
+            Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", "true");
+            try
+            {
+                // Arrange
+                Setup();
+                const string RepoName = "my-org/my-repo";
+                const string RepoSha = "abc123def456";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RepoSha);
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RepoName;
+                jobContext.WorkflowSha = RepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                // Stage parent action on disk as a composite that uses $/actions/child.
+                // We use rootStepId != default to avoid directory deletion,
+                // and create the watermark + action.yml in the expected location.
+                string actionsDir = Path.Combine(_workFolder, Constants.Path.ActionsDirectory);
+                string destDir = Path.Combine(actionsDir, RepoName.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), RepoSha);
+                Directory.CreateDirectory(Path.Combine(destDir, "actions", "parent"));
+                File.WriteAllText(Path.Combine(destDir, "actions", "parent", Constants.Path.ActionManifestYmlFile), @"
+name: 'Parent'
+description: 'Composite parent'
+runs:
+  using: 'composite'
+  steps:
+    - uses: $/actions/child
+");
+                // Stage child action too (as a leaf node action)
+                Directory.CreateDirectory(Path.Combine(destDir, "actions", "child"));
+                File.WriteAllText(Path.Combine(destDir, "actions", "child", Constants.Path.ActionManifestYmlFile), @"
+name: 'Child'
+description: 'Node child'
+runs:
+  using: 'node20'
+  main: 'index.js'
+");
+                // Write watermark
+                File.WriteAllText($"{destDir}.completed", string.Empty);
+
+                var rootStepId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = Guid.NewGuid(),
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "actions/parent"
+                        }
+                    }
+                };
+
+                // Act — should resolve $/ and not throw InvalidOperationException
+                await _actionManager.PrepareActionsAsync(_ec.Object, actions, rootStepId);
+
+                // Assert — top-level $/ resolved
+                var topRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, topRef.RepositoryType);
+                Assert.Equal(RepoName, topRef.Name);
+                Assert.Equal(RepoSha, topRef.Ref);
+                Assert.Equal("actions/parent", topRef.Path);
+            }
+            finally
+            {
+                Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", null);
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_CrossRepoCompositeResolvesToParentRepo()
+        {
+            // External composite (external/foo@v1) uses $/lib/bar.
+            // $/lib/bar should resolve to external/foo@v1 (the parent's repo),
+            // NOT to the workflow's root repo.
+            Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", "true");
+            try
+            {
+                // Arrange
+                Setup();
+                const string RootRepoName = "my-org/my-repo";
+                const string RootRepoSha = "root-sha-111";
+                const string ExtRepoName = "external/foo";
+                const string ExtRepoRef = "v1";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RootRepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RootRepoSha);
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RootRepoName;
+                jobContext.WorkflowSha = RootRepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                string actionsDir = Path.Combine(_workFolder, Constants.Path.ActionsDirectory);
+                string destDir = Path.Combine(actionsDir, ExtRepoName.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), ExtRepoRef);
+                Directory.CreateDirectory(destDir);
+                File.WriteAllText(Path.Combine(destDir, Constants.Path.ActionManifestYmlFile), @"
+name: 'External Foo'
+description: 'External composite'
+runs:
+  using: 'composite'
+  steps:
+    - uses: $/lib/bar
+");
+                Directory.CreateDirectory(Path.Combine(destDir, "lib", "bar"));
+                File.WriteAllText(Path.Combine(destDir, "lib", "bar", Constants.Path.ActionManifestYmlFile), @"
+name: 'Bar'
+description: 'Node action in external repo'
+runs:
+  using: 'node20'
+  main: 'index.js'
+");
+                File.WriteAllText($"{destDir}.completed", string.Empty);
+
+                var rootStepId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = Guid.NewGuid(),
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            Name = ExtRepoName,
+                            Ref = ExtRepoRef,
+                            RepositoryType = Pipelines.RepositoryTypes.GitHub
+                        }
+                    }
+                };
+
+                // Act — should resolve $/lib/bar to external/foo@v1/lib/bar
+                await _actionManager.PrepareActionsAsync(_ec.Object, actions, rootStepId);
+
+                // Assert — the top-level ref is unchanged (it was already concrete)
+                var topRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(ExtRepoName, topRef.Name);
+                Assert.Equal(ExtRepoRef, topRef.Ref);
+            }
+            finally
+            {
+                Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", null);
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_MultiLevelChain()
+        {
+            // $/a → composite → $/b → composite → $/c (three levels, same repo)
+            Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", "true");
+            try
+            {
+                // Arrange
+                Setup();
+                const string RepoName = "my-org/my-repo";
+                const string RepoSha = "chain-sha-222";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RepoSha);
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RepoName;
+                jobContext.WorkflowSha = RepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                string actionsDir = Path.Combine(_workFolder, Constants.Path.ActionsDirectory);
+                string destDir = Path.Combine(actionsDir, RepoName.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), RepoSha);
+                Directory.CreateDirectory(Path.Combine(destDir, "a"));
+                File.WriteAllText(Path.Combine(destDir, "a", Constants.Path.ActionManifestYmlFile), @"
+name: 'A'
+description: 'Level 0 composite'
+runs:
+  using: 'composite'
+  steps:
+    - uses: $/b
+");
+                Directory.CreateDirectory(Path.Combine(destDir, "b"));
+                File.WriteAllText(Path.Combine(destDir, "b", Constants.Path.ActionManifestYmlFile), @"
+name: 'B'
+description: 'Level 1 composite'
+runs:
+  using: 'composite'
+  steps:
+    - uses: $/c
+");
+                Directory.CreateDirectory(Path.Combine(destDir, "c"));
+                File.WriteAllText(Path.Combine(destDir, "c", Constants.Path.ActionManifestYmlFile), @"
+name: 'C'
+description: 'Level 2 node leaf'
+runs:
+  using: 'node20'
+  main: 'index.js'
+");
+                File.WriteAllText($"{destDir}.completed", string.Empty);
+
+                var rootStepId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = Guid.NewGuid(),
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "a"
+                        }
+                    }
+                };
+
+                // Act — three-level $/ chain should resolve without error
+                await _actionManager.PrepareActionsAsync(_ec.Object, actions, rootStepId);
+
+                // Assert — top-level ref resolved
+                var topRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, topRef.RepositoryType);
+                Assert.Equal(RepoName, topRef.Name);
+                Assert.Equal(RepoSha, topRef.Ref);
+                Assert.Equal("a", topRef.Path);
+            }
+            finally
+            {
+                Environment.SetEnvironmentVariable("ACTIONS_BATCH_ACTION_RESOLUTION", null);
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_ResolvesAtDepthZero_LegacyPath()
+        {
+            // Same as ResolvesAtDepthZero but on the legacy (non-batch) path
+            try
+            {
+                // Arrange
+                Setup();
+                const string RepoName = "my-org/my-repo";
+                const string RepoSha = "abc123def456";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RepoSha);
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RepoName;
+                jobContext.WorkflowSha = RepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                var actionId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = actionId,
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "actions/my-action"
+                        }
+                    }
+                };
+
+                string archiveFile = await CreateRepoArchive();
+                using var stream = File.OpenRead(archiveFile);
+                string archiveLink = GetLinkToActionArchive("https://api.github.com", RepoName, RepoSha);
+                var mockClientHandler = new Mock<HttpClientHandler>();
+                mockClientHandler.Protected().Setup<Task<HttpResponseMessage>>("SendAsync", ItExpr.Is<HttpRequestMessage>(m => m.RequestUri == new Uri(archiveLink)), ItExpr.IsAny<CancellationToken>())
+                    .ReturnsAsync(new HttpResponseMessage(HttpStatusCode.OK) { Content = new StreamContent(stream) });
+                var mockHandlerFactory = new Mock<IHttpClientHandlerFactory>();
+                mockHandlerFactory.Setup(p => p.CreateClientHandler(It.IsAny<RunnerWebProxy>())).Returns(mockClientHandler.Object);
+                _hc.SetSingleton(mockHandlerFactory.Object);
+
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+
+                // Act
+                try
+                {
+                    await _actionManager.PrepareActionsAsync(_ec.Object, actions);
+                }
+                catch (InvalidOperationException ex) when (ex.Message.Contains("Can't find"))
+                {
+                    // Expected: test archive lacks the action.yml at the resolved subpath
+                }
+
+                // Assert — the reference should be resolved to a GitHub repo reference
+                var repoRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, repoRef.RepositoryType);
+                Assert.Equal(RepoName, repoRef.Name);
+                Assert.Equal(RepoSha, repoRef.Ref);
+                Assert.Equal("actions/my-action", repoRef.Path);
+            }
+            finally
+            {
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SelfRepository_ResolvesNestedInComposite_LegacyPath()
+        {
+            // Same as ResolvesNestedInComposite but on the legacy (non-batch) path.
+            // Verifies that $/ resolution works when batch action resolution is disabled.
+            try
+            {
+                // Arrange
+                Setup();
+                const string RepoName = "my-org/my-repo";
+                const string RepoSha = "abc123def456";
+                _ec.Setup(x => x.GetGitHubContext("repository")).Returns(RepoName);
+                _ec.Setup(x => x.GetGitHubContext("sha")).Returns(RepoSha);
+                _ec.Setup(x => x.GetGitHubContext("api_url")).Returns("https://api.github.com");
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = RepoName;
+                jobContext.WorkflowSha = RepoSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                // Stage parent action on disk as a composite that uses $/actions/child.
+                string actionsDir = Path.Combine(_workFolder, Constants.Path.ActionsDirectory);
+                string destDir = Path.Combine(actionsDir, RepoName.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), RepoSha);
+                Directory.CreateDirectory(Path.Combine(destDir, "actions", "parent"));
+                File.WriteAllText(Path.Combine(destDir, "actions", "parent", Constants.Path.ActionManifestYmlFile), @"
+name: 'Parent'
+description: 'Composite parent'
+runs:
+  using: 'composite'
+  steps:
+    - uses: $/actions/child
+");
+                // Stage child action too (as a leaf node action)
+                Directory.CreateDirectory(Path.Combine(destDir, "actions", "child"));
+                File.WriteAllText(Path.Combine(destDir, "actions", "child", Constants.Path.ActionManifestYmlFile), @"
+name: 'Child'
+description: 'Node child'
+runs:
+  using: 'node20'
+  main: 'index.js'
+");
+                // Write watermark
+                File.WriteAllText($"{destDir}.completed", string.Empty);
+
+                var rootStepId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = Guid.NewGuid(),
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            RepositoryType = Pipelines.PipelineConstants.SelfRepositoryAlias,
+                            Path = "actions/parent"
+                        }
+                    }
+                };
+
+                // Act — should resolve $/ and not throw InvalidOperationException
+                await _actionManager.PrepareActionsAsync(_ec.Object, actions, rootStepId);
+
+                // Assert — top-level $/ resolved
+                var topRef = actions[0].Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, topRef.RepositoryType);
+                Assert.Equal(RepoName, topRef.Name);
+                Assert.Equal(RepoSha, topRef.Ref);
+                Assert.Equal("actions/parent", topRef.Path);
+            }
+            finally
+            {
+                Teardown();
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public void LoadAction_DotSlashCompositeWithNestedSelfRepository_ResolvesViaWorkflowContext()
+        {
+            // Regression test: when a dot-slash (./) composite action contains a
+            // nested $/actions/child step, LoadAction re-parses the action.yml at
+            // runtime and must resolve the $/ ref. The parent is repositoryType "self"
+            // so its Name and Ref are null — resolution must fall back to
+            // WorkflowRepository/WorkflowSha from the job context. Before the fix,
+            // this path hit a NullReferenceException at repoAction.Name.Replace().
+            try
+            {
+                // Arrange
+                Setup();
+                const string WorkflowRepo = "my-org/my-repo";
+                const string WorkflowSha = "abc123def456";
+                _ec.Object.Global.Variables.Set(Constants.Runner.Features.SelfRepository, "true");
+                var jobContext = new JobContext();
+                jobContext.WorkflowRepository = WorkflowRepo;
+                jobContext.WorkflowSha = WorkflowSha;
+                _ec.Setup(x => x.JobContext).Returns(jobContext);
+
+                // Stage the dot-slash composite in the workspace directory.
+                // It contains a nested $/actions/child step.
+                string workspaceDir = Path.Combine(_workFolder, "actions", "actions");
+                string compositeDir = Path.Combine(workspaceDir, "my-composite");
+                Directory.CreateDirectory(compositeDir);
+                File.WriteAllText(Path.Combine(compositeDir, Constants.Path.ActionManifestYmlFile), @"
+name: 'DotSlash Parent'
+description: 'Composite loaded via ./ that nests a $/ ref'
+runs:
+  using: 'composite'
+  steps:
+    - run: echo 'hello'
+      shell: bash
+    - uses: $/actions/child
+");
+
+                // Stage the child action in the actions cache under the workflow repo.
+                string actionsDir = Path.Combine(_workFolder, Constants.Path.ActionsDirectory);
+                string childDir = Path.Combine(actionsDir, WorkflowRepo.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), WorkflowSha, "actions", "child");
+                Directory.CreateDirectory(childDir);
+                File.WriteAllText(Path.Combine(childDir, Constants.Path.ActionManifestYmlFile), @"
+name: 'Child'
+description: 'Leaf action'
+runs:
+  using: 'node20'
+  main: 'index.js'
+");
+
+                // Create dot-slash step with Name = null (the real scenario).
+                var instance = new Pipelines.ActionStep()
+                {
+                    Id = Guid.NewGuid(),
+                    Reference = new Pipelines.RepositoryPathReference()
+                    {
+                        Name = null,
+                        Ref = null,
+                        RepositoryType = Pipelines.PipelineConstants.SelfAlias,
+                        Path = "my-composite"
+                    }
+                };
+
+                // Act — should NOT throw NullReferenceException
+                Definition definition = _actionManager.LoadAction(_ec.Object, instance);
+
+                // Assert — loaded the composite successfully
+                Assert.NotNull(definition);
+                Assert.NotNull(definition.Data);
+                Assert.Equal(ActionExecutionType.Composite, definition.Data.Execution.ExecutionType);
+
+                // Assert — the nested $/ step was resolved to the workflow repo
+                var compositeData = definition.Data.Execution as CompositeActionExecutionData;
+                Assert.NotNull(compositeData);
+                var childStep = compositeData.Steps
+                    .OfType<Pipelines.ActionStep>()
+                    .FirstOrDefault(s => s.Reference is Pipelines.RepositoryPathReference r
+                        && r.Path == "actions/child");
+                Assert.NotNull(childStep);
+                var childRef = childStep.Reference as Pipelines.RepositoryPathReference;
+                Assert.Equal(Pipelines.RepositoryTypes.GitHub, childRef.RepositoryType);
+                Assert.Equal(WorkflowRepo, childRef.Name);
+                Assert.Equal(WorkflowSha, childRef.Ref);
+            }
+            finally
+            {
+                Teardown();
+            }
+        }
+
     }
 }

src/Test/L0/Worker/HandlerL0.cs

@@ -1,19 +1,10 @@
 using System;
-using System.Collections.Generic;
-using System.IO;
 using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
-using System.Threading;
-using System.Threading.Tasks;
 using GitHub.Actions.RunService.WebApi;
 using GitHub.DistributedTask.Pipelines;
-using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
 using GitHub.Runner.Worker;
-using GitHub.Runner.Worker.Container;
-using GitHub.Runner.Worker.Container.ContainerHooks;
 using GitHub.Runner.Worker.Handlers;
 using Moq;
 using Xunit;
@@ -94,260 +85,5 @@ namespace GitHub.Runner.Common.Tests.Worker
                 Assert.Equal("ubuntu:20.04", _stepTelemetry.Action);
             }
         }
-
-        [Theory]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        [InlineData("read")]
-        [InlineData("none")]
-        [InlineData("write")]
-        [InlineData("write-only")]
-        public async Task RunAsync_ExportsCacheModeEnv_WhenVariableSet(string mode)
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var environment = await RunNodeScriptActionHandlerAsync(hc, new Dictionary<string, VariableValue>
-                {
-                    { "actions_cache_mode", mode }
-                });
-
-                Assert.True(environment.TryGetValue("ACTIONS_CACHE_MODE", out var value));
-                Assert.Equal(mode, value);
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task RunAsync_DoesNotExportCacheModeEnv_WhenVariableAbsent()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var environment = await RunNodeScriptActionHandlerAsync(hc, new Dictionary<string, VariableValue>());
-
-                Assert.False(environment.ContainsKey("ACTIONS_CACHE_MODE"));
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task RunAsync_DoesNotExportCacheModeEnv_WhenVariableEmpty()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var environment = await RunNodeScriptActionHandlerAsync(hc, new Dictionary<string, VariableValue>
-                {
-                    { "actions_cache_mode", "" }
-                });
-
-                Assert.False(environment.ContainsKey("ACTIONS_CACHE_MODE"));
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task RunAsync_CacheModeCoexistsWithCacheServiceV2()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var environment = await RunNodeScriptActionHandlerAsync(hc, new Dictionary<string, VariableValue>
-                {
-                    { "actions_uses_cache_service_v2", "true" },
-                    { "actions_cache_mode", "read" }
-                });
-
-                Assert.Equal(bool.TrueString, environment["ACTIONS_CACHE_SERVICE_V2"]);
-                Assert.Equal("read", environment["ACTIONS_CACHE_MODE"]);
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task RunAsync_DoesNotAffectRuntimeEnv_WhenCacheModeAbsent()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var environment = await RunNodeScriptActionHandlerAsync(hc, new Dictionary<string, VariableValue>());
-
-                // Baseline runtime env is still exported and cache-mode adds nothing.
-                Assert.Equal("https://pipelines.actions.githubusercontent.com/", environment["ACTIONS_RUNTIME_URL"]);
-                Assert.Equal("token", environment["ACTIONS_RUNTIME_TOKEN"]);
-                Assert.False(environment.ContainsKey("ACTIONS_CACHE_MODE"));
-                Assert.False(environment.ContainsKey("ACTIONS_CACHE_SERVICE_V2"));
-            }
-        }
-
-        [Theory]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        [InlineData("read")]
-        [InlineData("none")]
-        public async Task ContainerRunAsync_ExportsCacheModeEnv_WhenVariableSet(string mode)
-        {
-            // Container actions only run on Linux; RunAsync throws on other platforms.
-            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
-            {
-                return;
-            }
-
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var container = await RunContainerActionHandlerAsync(hc, new Dictionary<string, VariableValue>
-                {
-                    { "actions_cache_mode", mode }
-                });
-
-                Assert.True(container.ContainerEnvironmentVariables.TryGetValue("ACTIONS_CACHE_MODE", out var value));
-                Assert.Equal(mode, value);
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task ContainerRunAsync_DoesNotExportCacheModeEnv_WhenVariableAbsent()
-        {
-            // Container actions only run on Linux; RunAsync throws on other platforms.
-            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
-            {
-                return;
-            }
-
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var container = await RunContainerActionHandlerAsync(hc, new Dictionary<string, VariableValue>());
-
-                Assert.False(container.ContainerEnvironmentVariables.ContainsKey("ACTIONS_CACHE_MODE"));
-            }
-        }
-
-        private async Task<ContainerInfo> RunContainerActionHandlerAsync(TestHostContext hc, IDictionary<string, VariableValue> variables)
-        {
-            // Route through the container-hooks path so the handler skips docker build/run.
-            variables[Constants.Runner.Features.AllowRunnerContainerHooks] = "true";
-            Environment.SetEnvironmentVariable(Constants.Hooks.ContainerHooksPath, Path.Combine(hc.GetDirectory(WellKnownDirectory.Root), "hooks.js"));
-
-            var tempDirectory = hc.GetDirectory(WellKnownDirectory.Temp);
-            Directory.CreateDirectory(Path.Combine(tempDirectory, "_runner_file_commands"));
-            Directory.CreateDirectory(Path.Combine(tempDirectory, "_github_workflow"));
-            var workspace = Path.Combine(hc.GetDirectory(WellKnownDirectory.Work), "workspace");
-            Directory.CreateDirectory(workspace);
-
-            var serverVariables = new Variables(hc, variables);
-            var endpoints = new List<ServiceEndpoint>
-            {
-                new ServiceEndpoint()
-                {
-                    Name = WellKnownServiceEndpointNames.SystemVssConnection,
-                    Url = new Uri("https://pipelines.actions.githubusercontent.com"),
-                    Authorization = new EndpointAuthorization()
-                    {
-                        Scheme = "Test",
-                        Parameters = { { "AccessToken", "token" } }
-                    }
-                }
-            };
-
-            _ec.Setup(x => x.Global).Returns(new GlobalContext()
-            {
-                Variables = serverVariables,
-                Endpoints = endpoints,
-                PrependPath = new List<string>(),
-                EnvironmentVariables = new Dictionary<string, string>()
-            });
-            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
-            _ec.Setup(x => x.JobContext).Returns(new JobContext());
-            _ec.Setup(x => x.GetGitHubContext("workspace")).Returns(workspace);
-
-            ContainerInfo captured = null;
-            var hookManager = new Mock<IContainerHookManager>();
-            hookManager.Setup(x => x.RunContainerStepAsync(It.IsAny<IExecutionContext>(), It.IsAny<ContainerInfo>(), It.IsAny<string>()))
-                       .Callback((IExecutionContext ec, ContainerInfo container, string dockerFile) => { captured = container; })
-                       .Returns(Task.CompletedTask);
-            hc.SetSingleton(hookManager.Object);
-            hc.SetSingleton(new Mock<IActionManifestManagerWrapper>().Object);
-
-            var handler = new ContainerActionHandler();
-            handler.Initialize(hc);
-            handler.ExecutionContext = _ec.Object;
-            handler.Environment = new Dictionary<string, string>();
-            handler.Inputs = new Dictionary<string, string>();
-            handler.Action = new ContainerRegistryReference() { Image = "alpine:latest" };
-            handler.Data = new ContainerActionExecutionData() { Image = "docker://alpine:latest" };
-
-            await handler.RunAsync(ActionRunStage.Main);
-
-            return captured;
-        }
-
-        private async Task<Dictionary<string, string>> RunNodeScriptActionHandlerAsync(TestHostContext hc, IDictionary<string, VariableValue> variables)
-        {
-            var actionDirectory = Path.Combine(hc.GetDirectory(WellKnownDirectory.Work), Guid.NewGuid().ToString());
-            Directory.CreateDirectory(actionDirectory);
-            var scriptFile = "main.js";
-            File.WriteAllText(Path.Combine(actionDirectory, scriptFile), "// noop");
-
-            var serverVariables = new Variables(hc, variables);
-            var endpoints = new List<ServiceEndpoint>
-            {
-                new ServiceEndpoint()
-                {
-                    Name = WellKnownServiceEndpointNames.SystemVssConnection,
-                    Url = new Uri("https://pipelines.actions.githubusercontent.com"),
-                    Authorization = new EndpointAuthorization()
-                    {
-                        Scheme = "Test",
-                        Parameters = { { "AccessToken", "token" } }
-                    }
-                }
-            };
-
-            _ec.Setup(x => x.Global).Returns(new GlobalContext()
-            {
-                Variables = serverVariables,
-                Endpoints = endpoints,
-                PrependPath = new List<string>(),
-                EnvironmentVariables = new Dictionary<string, string>()
-            });
-            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
-            _ec.Setup(x => x.GetGitHubContext("workspace")).Returns(actionDirectory);
-            _ec.Setup(x => x.GetMatchers()).Returns(new List<IssueMatcherConfig>());
-            _ec.Setup(x => x.ForceCompleted).Returns(new TaskCompletionSource<int>().Task);
-            _ec.Setup(x => x.CancellationToken).Returns(CancellationToken.None);
-
-            var stepHost = new Mock<IStepHost>();
-            stepHost.Setup(x => x.DetermineNodeRuntimeVersion(It.IsAny<IExecutionContext>(), It.IsAny<string>())).ReturnsAsync("node20");
-            stepHost.Setup(x => x.ResolvePathForStepHost(It.IsAny<IExecutionContext>(), It.IsAny<string>())).Returns((IExecutionContext ec, string path) => path);
-            stepHost.Setup(x => x.ExecuteAsync(
-                It.IsAny<IExecutionContext>(),
-                It.IsAny<string>(),
-                It.IsAny<string>(),
-                It.IsAny<string>(),
-                It.IsAny<IDictionary<string, string>>(),
-                It.IsAny<bool>(),
-                It.IsAny<System.Text.Encoding>(),
-                It.IsAny<bool>(),
-                It.IsAny<bool>(),
-                It.IsAny<string>(),
-                It.IsAny<CancellationToken>())).ReturnsAsync(0);
-
-            var handler = new NodeScriptActionHandler();
-            handler.Initialize(hc);
-            handler.ExecutionContext = _ec.Object;
-            handler.StepHost = stepHost.Object;
-            handler.Environment = new Dictionary<string, string>();
-            handler.Inputs = new Dictionary<string, string>();
-            handler.RuntimeVariables = serverVariables;
-            handler.ActionDirectory = actionDirectory;
-            handler.Action = new RepositoryPathReference() { Name = "actions/checkout", Ref = "v2" };
-            handler.Data = new NodeJSActionExecutionData() { Script = scriptFile, NodeVersion = "node20" };
-
-            await handler.RunAsync(ActionRunStage.Main);
-
-            return handler.Environment;
-        }
     }
 }

src/Test/L0/Worker/JobExtensionL0.cs

@@ -238,54 +238,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             }
         }
 
-        [Theory]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        [InlineData("read")]
-        [InlineData("none")]
-        [InlineData("write")]
-        [InlineData("write-only")]
-        public async Task InitializeJob_LogsCacheMode_WhenVariableSet(string mode)
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                _jobEc.Global.Variables.Set("actions_cache_mode", mode);
-
-                var jobExtension = new JobExtension();
-                jobExtension.Initialize(hc);
-
-                _actionManager.Setup(x => x.PrepareActionsAsync(It.IsAny<IExecutionContext>(), It.IsAny<IEnumerable<Pipelines.JobStep>>(), It.IsAny<Guid>()))
-                              .Returns(Task.FromResult(new PrepareResult(new List<JobExtensionRunner>(), new Dictionary<Guid, IActionRunner>())));
-
-                await jobExtension.InitializeJob(_jobEc, _message);
-
-                _jobServerQueue.Verify(
-                    x => x.QueueWebConsoleLine(It.IsAny<Guid>(), It.Is<string>(m => m.Contains($"Actions cache-mode: {mode}")), It.IsAny<long?>()),
-                    Times.Once);
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public async Task InitializeJob_DoesNotLogCacheMode_WhenVariableAbsent()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                var jobExtension = new JobExtension();
-                jobExtension.Initialize(hc);
-
-                _actionManager.Setup(x => x.PrepareActionsAsync(It.IsAny<IExecutionContext>(), It.IsAny<IEnumerable<Pipelines.JobStep>>(), It.IsAny<Guid>()))
-                              .Returns(Task.FromResult(new PrepareResult(new List<JobExtensionRunner>(), new Dictionary<Guid, IActionRunner>())));
-
-                await jobExtension.InitializeJob(_jobEc, _message);
-
-                _jobServerQueue.Verify(
-                    x => x.QueueWebConsoleLine(It.IsAny<Guid>(), It.Is<string>(m => m.Contains("Actions cache-mode:")), It.IsAny<long?>()),
-                    Times.Never);
-            }
-        }
-
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]