prepare 2.168.0 runner release.

releaseNote.md

@@ -1,27 +1,24 @@
 ## Features
-  - Expose whether debug is on/off via RUNNER_DEBUG. (#253)
-  - Upload log on runner when worker get killed due to cancellation timeout. (#255)
-  - Update config.sh/cmd --help documentation (#282) 
-  - Set http_proxy and related env vars for job/service containers (#304)
-  - Set both http_proxy and HTTP_PROXY env for runner/worker processes. (#298)
+  - Update Runner Register GitHub API URL to Support Org-level Runner (#339 #345 #352) 
+  - Preserve workflow file/line/column for better error messages (#356)
+  - Switch to use token service instead of SPS for exchanging oauth token. (#325)
+  - Load and print machine setup info from .setup_info (#364)
+  - Expose job name as $GITHUB_JOB (#366)
+  - Add support for job outputs. (#365) 
+  - Set CI=true when launch process in actions runner. (#374)
+  - Set steps.<id>.outcome and steps.<id>.conclusion. (#372)
+  - Add support for workflow/job defaults. (#369)
+  - Expose GITHUB_REPOSITORY_OWNER and ${{github.repository_owner}}. (#378)
 
 ## Bugs
-  - Verify runner Windows service hash started successfully after configuration (#236)
-  - Detect source file path in L0 without using env. (#257)
-  - Handle escaped '%' in commands data section (#200)
-  - Allow container to be null/empty during matrix expansion (#266)
-  - Translate problem matcher file to host path (#272)
-  - Change hashFiles() expression function to use @actions/glob. (#268)
-  - Default post-job action's condition to always(). (#293)
-  - Support action.yaml file as action's entry file (#288) 
-  - Trace javascript action exit code to debug instead of user logs (#290)
-  - Change prompt message when removing a runner to lines up with GitHub.com UI (#303) 
-  - Include step.env as part of env context. (#300)
-  - Update Base64 Encoders to deal with suffixes (#284)
+  - Use authenticate endpoint for testing runner connection. (#311) 
+  - Commands translate file path from container action (#331)
+  - Change problem matchers output to debug (#363)
+  - Switch hashFiles to extension function (#362)
+  - Add expanded volumes strings to container mounts (#384)
 
 ## Misc
-  - Move .sln file under ./src (#238)
-  - Treat warnings as errors during compile (#249) 
+  - Add runner auth documentation (#357) 
 
 ## Windows x64
 We recommend configuring the runner in a root folder of the Windows drive (e.g. "C:\actions-runner"). This will help avoid issues related to service identity folder permissions and long file path restrictions on Windows

src/Runner.Worker/ActionManifestManager.cs

@@ -22,11 +22,11 @@ namespace GitHub.Runner.Worker
     {
         ActionDefinitionData Load(IExecutionContext executionContext, string manifestFile);
 
-        List<string> EvaluateContainerArguments(IExecutionContext executionContext, SequenceToken token, IDictionary<string, PipelineContextData> contextData);
+        List<string> EvaluateContainerArguments(IExecutionContext executionContext, SequenceToken token, IDictionary<string, PipelineContextData> extraExpressionValues);
 
-        Dictionary<string, string> EvaluateContainerEnvironment(IExecutionContext executionContext, MappingToken token, IDictionary<string, PipelineContextData> contextData);
+        Dictionary<string, string> EvaluateContainerEnvironment(IExecutionContext executionContext, MappingToken token, IDictionary<string, PipelineContextData> extraExpressionValues);
 
-        string EvaluateDefaultInput(IExecutionContext executionContext, string inputName, TemplateToken token, IDictionary<string, PipelineContextData> contextData);
+        string EvaluateDefaultInput(IExecutionContext executionContext, string inputName, TemplateToken token);
     }
 
     public sealed class ActionManifestManager : RunnerService, IActionManifestManager
@@ -54,7 +54,7 @@ namespace GitHub.Runner.Worker
 
         public ActionDefinitionData Load(IExecutionContext executionContext, string manifestFile)
         {
-            var context = CreateContext(executionContext, null);
+            var context = CreateContext(executionContext);
             ActionDefinitionData actionDefinition = new ActionDefinitionData();
             try
             {
@@ -133,13 +133,13 @@ namespace GitHub.Runner.Worker
         public List<string> EvaluateContainerArguments(
             IExecutionContext executionContext,
             SequenceToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues)
         {
             var result = new List<string>();
 
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext, extraExpressionValues);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "container-runs-args", token, 0, null, omitHeader: true);
@@ -172,13 +172,13 @@ namespace GitHub.Runner.Worker
         public Dictionary<string, string> EvaluateContainerEnvironment(
             IExecutionContext executionContext,
             MappingToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues)
         {
             var result = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
 
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext, extraExpressionValues);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "container-runs-env", token, 0, null, omitHeader: true);
@@ -216,13 +216,12 @@ namespace GitHub.Runner.Worker
         public string EvaluateDefaultInput(
             IExecutionContext executionContext,
             string inputName,
-            TemplateToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            TemplateToken token)
         {
             string result = "";
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "input-default-context", token, 0, null, omitHeader: true);
@@ -247,7 +246,7 @@ namespace GitHub.Runner.Worker
 
         private TemplateContext CreateContext(
             IExecutionContext executionContext,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues = null)
         {
             var result = new TemplateContext
             {
@@ -261,12 +260,25 @@ namespace GitHub.Runner.Worker
                 TraceWriter = executionContext.ToTemplateTraceWriter(),
             };
 
-            if (contextData?.Count > 0)
-            {
-                foreach (var pair in contextData)
+            // Expression values from execution context
+            foreach (var pair in executionContext.ExpressionValues)
             {
                 result.ExpressionValues[pair.Key] = pair.Value;
             }
+
+            // Extra expression values
+            if (extraExpressionValues?.Count > 0)
+            {
+                foreach (var pair in extraExpressionValues)
+                {
+                    result.ExpressionValues[pair.Key] = pair.Value;
+                }
+            }
+
+            // Expression functions from execution context
+            foreach (var item in executionContext.ExpressionFunctions)
+            {
+                result.ExpressionFunctions.Add(item);
             }
 
             // Add the file table

src/Runner.Worker/ActionRunner.cs

@@ -26,7 +26,7 @@ namespace GitHub.Runner.Worker
     public interface IActionRunner : IStep, IRunnerService
     {
         ActionRunStage Stage { get; set; }
-        Boolean TryEvaluateDisplayName(DictionaryContextData contextData, IExecutionContext context);
+        bool TryEvaluateDisplayName(DictionaryContextData contextData, IExecutionContext context);
         Pipelines.ActionStep Action { get; set; }
     }
 
@@ -142,7 +142,7 @@ namespace GitHub.Runner.Worker
             // Load the inputs.
             ExecutionContext.Debug("Loading inputs");
             var templateEvaluator = ExecutionContext.ToPipelineTemplateEvaluator();
-            var inputs = templateEvaluator.EvaluateStepInputs(Action.Inputs, ExecutionContext.ExpressionValues);
+            var inputs = templateEvaluator.EvaluateStepInputs(Action.Inputs, ExecutionContext.ExpressionValues, ExecutionContext.ExpressionFunctions);
 
             foreach (KeyValuePair<string, string> input in inputs)
             {
@@ -162,13 +162,7 @@ namespace GitHub.Runner.Worker
                     string key = input.Key.AssertString("action input name").Value;
                     if (!inputs.ContainsKey(key))
                     {
-                        var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-                        foreach (var data in ExecutionContext.ExpressionValues)
-                        {
-                            evaluateContext[data.Key] = data.Value;
-                        }
-
-                        inputs[key] = manifestManager.EvaluateDefaultInput(ExecutionContext, key, input.Value, evaluateContext);
+                        inputs[key] = manifestManager.EvaluateDefaultInput(ExecutionContext, key, input.Value);
                     }
                 }
             }
@@ -293,10 +287,14 @@ namespace GitHub.Runner.Worker
                 return displayName;
             }
             // Try evaluating fully
-            var templateEvaluator = context.ToPipelineTemplateEvaluator();
             try
             {
-                didFullyEvaluate = templateEvaluator.TryEvaluateStepDisplayName(tokenToParse, contextData, out displayName);
+                if (tokenToParse.CheckHasRequiredContext(contextData, context.ExpressionFunctions))
+                {
+                    var templateEvaluator = context.ToPipelineTemplateEvaluator();
+                    displayName = templateEvaluator.EvaluateStepDisplayName(tokenToParse, contextData, context.ExpressionFunctions);
+                    didFullyEvaluate = true;
+                }
             }
             catch (TemplateValidationException e)
             {

src/Runner.Worker/Container/ContainerInfo.cs

@@ -61,6 +61,7 @@ namespace GitHub.Runner.Worker.Container
                 foreach (var volume in container.Volumes)
                 {
                     UserMountVolumes[volume] = volume;
+                    MountVolumes.Add(new MountVolume(volume));
                 }
             }
 

src/Runner.Worker/Container/DockerCommandManager.cs

@@ -130,6 +130,13 @@ namespace GitHub.Runner.Worker.Container
             // Watermark for GitHub Action environment
             dockerOptions.Add("-e GITHUB_ACTIONS=true");
 
+            // Set CI=true when no one else already set it.
+            // CI=true is common set in most CI provider in GitHub
+            if (!container.ContainerEnvironmentVariables.ContainsKey("CI"))
+            {
+                dockerOptions.Add("-e CI=true");
+            }
+
             foreach (var volume in container.MountVolumes)
             {
                 // replace `"` with `\"` and add `"{0}"` to all path.
@@ -189,6 +196,13 @@ namespace GitHub.Runner.Worker.Container
             // Watermark for GitHub Action environment
             dockerOptions.Add("-e GITHUB_ACTIONS=true");
 
+            // Set CI=true when no one else already set it.
+            // CI=true is common set in most CI provider in GitHub
+            if (!container.ContainerEnvironmentVariables.ContainsKey("CI"))
+            {
+                dockerOptions.Add("-e CI=true");
+            }
+
             if (!string.IsNullOrEmpty(container.ContainerEntryPoint))
             {
                 dockerOptions.Add($"--entrypoint \"{container.ContainerEntryPoint}\"");

src/Runner.Worker/ExecutionContext.cs

@@ -1,14 +1,15 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
-using GitHub.Runner.Worker.Container;
-using GitHub.Services.WebApi;
+using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
@@ -16,12 +17,11 @@ using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Container;
+using GitHub.Services.WebApi;
 using Newtonsoft.Json;
-using System.Text;
-using System.Collections;
 using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
 using Pipelines = GitHub.DistributedTask.Pipelines;
-using GitHub.DistributedTask.Expressions2;
 
 namespace GitHub.Runner.Worker
 {
@@ -48,12 +48,14 @@ namespace GitHub.Runner.Worker
         PlanFeatures Features { get; }
         Variables Variables { get; }
         Dictionary<string, string> IntraActionState { get; }
+        IDictionary<String, IDictionary<String, String>> JobDefaults { get; }
         Dictionary<string, VariableValue> JobOutputs { get; }
         IDictionary<String, String> EnvironmentVariables { get; }
         IDictionary<String, ContextScope> Scopes { get; }
         IList<String> FileTable { get; }
         StepsContext StepsContext { get; }
         DictionaryContextData ExpressionValues { get; }
+        IList<IFunctionInfo> ExpressionFunctions { get; }
         List<string> PrependPath { get; }
         ContainerInfo Container { get; set; }
         List<ContainerInfo> ServiceContainers { get; }
@@ -140,12 +142,14 @@ namespace GitHub.Runner.Worker
         public List<ServiceEndpoint> Endpoints { get; private set; }
         public Variables Variables { get; private set; }
         public Dictionary<string, string> IntraActionState { get; private set; }
+        public IDictionary<String, IDictionary<String, String>> JobDefaults { get; private set; }
         public Dictionary<string, VariableValue> JobOutputs { get; private set; }
         public IDictionary<String, String> EnvironmentVariables { get; private set; }
         public IDictionary<String, ContextScope> Scopes { get; private set; }
         public IList<String> FileTable { get; private set; }
         public StepsContext StepsContext { get; private set; }
         public DictionaryContextData ExpressionValues { get; } = new DictionaryContextData();
+        public IList<IFunctionInfo> ExpressionFunctions { get; } = new List<IFunctionInfo>();
         public bool WriteDebug { get; private set; }
         public List<string> PrependPath { get; private set; }
         public ContainerInfo Container { get; set; }
@@ -270,6 +274,7 @@ namespace GitHub.Runner.Worker
                 child.IntraActionState = intraActionState;
             }
             child.EnvironmentVariables = EnvironmentVariables;
+            child.JobDefaults = JobDefaults;
             child.Scopes = Scopes;
             child.FileTable = FileTable;
             child.StepsContext = StepsContext;
@@ -277,6 +282,10 @@ namespace GitHub.Runner.Worker
             {
                 child.ExpressionValues[pair.Key] = pair.Value;
             }
+            foreach (var item in ExpressionFunctions)
+            {
+                child.ExpressionFunctions.Add(item);
+            }
             child._cancellationTokenSource = new CancellationTokenSource();
             child.WriteDebug = WriteDebug;
             child._parentExecutionContext = this;
@@ -565,6 +574,9 @@ namespace GitHub.Runner.Worker
             // Environment variables shared across all actions
             EnvironmentVariables = new Dictionary<string, string>(VarUtil.EnvironmentVariableKeyComparer);
 
+            // Job defaults shared across all actions
+            JobDefaults = new Dictionary<string, IDictionary<string, string>>(StringComparer.OrdinalIgnoreCase);
+
             // Job Outputs
             JobOutputs = new Dictionary<string, VariableValue>(StringComparer.OrdinalIgnoreCase);
 
@@ -587,12 +599,6 @@ namespace GitHub.Runner.Worker
             // File table
             FileTable = new List<String>(message.FileTable ?? new string[0]);
 
-            // Expression functions
-            if (Variables.GetBoolean("System.HashFilesV2") == true)
-            {
-                ExpressionConstants.UpdateFunction<Handlers.HashFiles>("hashFiles", 1, byte.MaxValue);
-            }
-
             // Expression values
             if (message.ContextData?.Count > 0)
             {
@@ -909,11 +915,19 @@ namespace GitHub.Runner.Worker
             }
         }
 
-        public static PipelineTemplateEvaluator ToPipelineTemplateEvaluator(this IExecutionContext context)
+        public static IEnumerable<KeyValuePair<string, object>> ToExpressionState(this IExecutionContext context)
         {
-            var templateTrace = context.ToTemplateTraceWriter();
-            var schema = new PipelineTemplateSchemaFactory().CreateSchema();
-            return new PipelineTemplateEvaluator(templateTrace, schema, context.FileTable);
+            return new[] { new KeyValuePair<string, object>(nameof(IExecutionContext), context) };
+        }
+
+        public static PipelineTemplateEvaluator ToPipelineTemplateEvaluator(this IExecutionContext context, ObjectTemplating.ITraceWriter traceWriter = null)
+        {
+            if (traceWriter == null)
+            {
+                traceWriter = context.ToTemplateTraceWriter();
+            }
+            var schema = PipelineTemplateSchemaFactory.GetSchema();
+            return new PipelineTemplateEvaluator(traceWriter, schema, context.FileTable);
         }
 
         public static ObjectTemplating.ITraceWriter ToTemplateTraceWriter(this IExecutionContext context)
@@ -928,6 +942,7 @@ namespace GitHub.Runner.Worker
 
         internal TemplateTraceWriter(IExecutionContext executionContext)
         {
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
             _executionContext = executionContext;
         }
 

src/Runner.Worker/ExpressionManager.cs

@@ -1,162 +0,0 @@
-using System;
-using System.Collections;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Expressions2.Sdk;
-using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Common;
-using GitHub.Runner.Common.Util;
-using GitHub.Runner.Sdk;
-using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
-using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
-
-namespace GitHub.Runner.Worker
-{
-    [ServiceLocator(Default = typeof(ExpressionManager))]
-    public interface IExpressionManager : IRunnerService
-    {
-        ConditionResult Evaluate(IExecutionContext context, string condition, bool hostTracingOnly = false);
-    }
-
-    public sealed class ExpressionManager : RunnerService, IExpressionManager
-    {
-        public ConditionResult Evaluate(IExecutionContext executionContext, string condition, bool hostTracingOnly = false)
-        {
-            ArgUtil.NotNull(executionContext, nameof(executionContext));
-
-            ConditionResult result = new ConditionResult();
-            var expressionTrace = new TraceWriter(Trace, hostTracingOnly ? null : executionContext);
-            var tree = Parse(executionContext, expressionTrace, condition);
-            var expressionResult = tree.Evaluate(expressionTrace, HostContext.SecretMasker, state: executionContext, options: null);
-            result.Value = expressionResult.IsTruthy;
-            result.Trace = expressionTrace.Trace;
-
-            return result;
-        }
-
-        private static IExpressionNode Parse(IExecutionContext executionContext, TraceWriter expressionTrace, string condition)
-        {
-            ArgUtil.NotNull(executionContext, nameof(executionContext));
-
-            if (string.IsNullOrWhiteSpace(condition))
-            {
-                condition = $"{PipelineTemplateConstants.Success}()";
-            }
-
-            var parser = new ExpressionParser();
-            var namedValues = executionContext.ExpressionValues.Keys.Select(x => new NamedValueInfo<ContextValueNode>(x)).ToArray();
-            var functions = new IFunctionInfo[]
-            {
-                new FunctionInfo<AlwaysNode>(name: Constants.Expressions.Always, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<CancelledNode>(name: Constants.Expressions.Cancelled, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<FailureNode>(name: Constants.Expressions.Failure, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<SuccessNode>(name: Constants.Expressions.Success, minParameters: 0, maxParameters: 0),
-            };
-            return parser.CreateTree(condition, expressionTrace, namedValues, functions) ?? new SuccessNode();
-        }
-
-        private sealed class TraceWriter : DistributedTask.Expressions2.ITraceWriter
-        {
-            private readonly IExecutionContext _executionContext;
-            private readonly Tracing _trace;
-            private readonly StringBuilder _traceBuilder = new StringBuilder();
-
-            public string Trace => _traceBuilder.ToString();
-
-            public TraceWriter(Tracing trace, IExecutionContext executionContext)
-            {
-                ArgUtil.NotNull(trace, nameof(trace));
-                _trace = trace;
-                _executionContext = executionContext;
-            }
-
-            public void Info(string message)
-            {
-                _trace.Info(message);
-                _executionContext?.Debug(message);
-                _traceBuilder.AppendLine(message);
-            }
-
-            public void Verbose(string message)
-            {
-                _trace.Verbose(message);
-                _executionContext?.Debug(message);
-            }
-        }
-
-        private sealed class AlwaysNode : Function
-        {
-            protected override Object EvaluateCore(EvaluationContext context, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                return true;
-            }
-        }
-
-        private sealed class CancelledNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Cancelled;
-            }
-        }
-
-        private sealed class FailureNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Failure;
-            }
-        }
-
-        private sealed class SuccessNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Success;
-            }
-        }
-
-        private sealed class ContextValueNode : NamedValue
-        {
-            protected override Object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var jobContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(jobContext, nameof(jobContext));
-                return jobContext.ExpressionValues[Name];
-            }
-        }
-    }
-
-    public class ConditionResult
-    {
-        public ConditionResult(bool value = false, string trace = null)
-        {
-            this.Value = value;
-            this.Trace = trace;
-        }
-
-        public bool Value { get; set; }
-        public string Trace { get; set; }
-
-        public static implicit operator ConditionResult(bool value)
-        {
-            return new ConditionResult(value);
-        }
-    }
-}

src/Runner.Worker/Expressions/AlwaysFunction.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class AlwaysFunction : Function
+    {
+        protected override Object EvaluateCore(EvaluationContext context, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            return true;
+        }
+    }
+}

src/Runner.Worker/Expressions/CancelledFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class CancelledFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Cancelled;
+        }
+    }
+}

src/Runner.Worker/Expressions/FailureFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class FailureFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Failure;
+        }
+    }
+}

src/Runner.Worker/Expressions/HashFilesFunction.cs

@@ -8,28 +8,9 @@ using System.Reflection;
 using System.Threading;
 using System.Collections.Generic;
 
-namespace GitHub.Runner.Worker.Handlers
+namespace GitHub.Runner.Worker.Expressions
 {
-    public class FunctionTrace : ITraceWriter
-    {
-        private GitHub.DistributedTask.Expressions2.ITraceWriter _trace;
-
-        public FunctionTrace(GitHub.DistributedTask.Expressions2.ITraceWriter trace)
-        {
-            _trace = trace;
-        }
-        public void Info(string message)
-        {
-            _trace.Info(message);
-        }
-
-        public void Verbose(string message)
-        {
-            _trace.Info(message);
-        }
-    }
-
-    public sealed class HashFiles : Function
+    public sealed class HashFilesFunction : Function
     {
         protected sealed override Object EvaluateCore(
             EvaluationContext context,
@@ -82,7 +63,7 @@ namespace GitHub.Runner.Worker.Handlers
             string node = Path.Combine(runnerRoot, "externals", "node12", "bin", $"node{IOUtil.ExeExtension}");
             string hashFilesScript = Path.Combine(binDir, "hashFiles");
             var hashResult = string.Empty;
-            var p = new ProcessInvoker(new FunctionTrace(context.Trace));
+            var p = new ProcessInvoker(new HashFilesTrace(context.Trace));
             p.ErrorDataReceived += ((_, data) =>
             {
                 if (!string.IsNullOrEmpty(data.Data) && data.Data.StartsWith("__OUTPUT__") && data.Data.EndsWith("__OUTPUT__"))
@@ -122,5 +103,24 @@ namespace GitHub.Runner.Worker.Handlers
 
             return hashResult;
         }
+
+        private sealed class HashFilesTrace : ITraceWriter
+        {
+            private GitHub.DistributedTask.Expressions2.ITraceWriter _trace;
+
+            public HashFilesTrace(GitHub.DistributedTask.Expressions2.ITraceWriter trace)
+            {
+                _trace = trace;
+            }
+            public void Info(string message)
+            {
+                _trace.Info(message);
+            }
+
+            public void Verbose(string message)
+            {
+                _trace.Info(message);
+            }
+        }
     }
 }

src/Runner.Worker/Expressions/SuccessFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class SuccessFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Success;
+        }
+    }
+}

src/Runner.Worker/GitHubContext.cs

@@ -17,6 +17,7 @@ namespace GitHub.Runner.Worker
             "job",
             "ref",
             "repository",
+            "repository_owner",
             "run_id",
             "run_number",
             "sha",

src/Runner.Worker/Handlers/ContainerActionHandler.cs

@@ -97,14 +97,14 @@ namespace GitHub.Runner.Worker.Handlers
                 }
             }
 
-            var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-            evaluateContext["inputs"] = inputsContext;
+            var extraExpressionValues = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
+            extraExpressionValues["inputs"] = inputsContext;
 
             var manifestManager = HostContext.GetService<IActionManifestManager>();
             if (Data.Arguments != null)
             {
                 container.ContainerEntryPointArgs = "";
-                var evaluatedArgs = manifestManager.EvaluateContainerArguments(ExecutionContext, Data.Arguments, evaluateContext);
+                var evaluatedArgs = manifestManager.EvaluateContainerArguments(ExecutionContext, Data.Arguments, extraExpressionValues);
                 foreach (var arg in evaluatedArgs)
                 {
                     if (!string.IsNullOrEmpty(arg))
@@ -124,7 +124,7 @@ namespace GitHub.Runner.Worker.Handlers
 
             if (Data.Environment != null)
             {
-                var evaluatedEnv = manifestManager.EvaluateContainerEnvironment(ExecutionContext, Data.Environment, evaluateContext);
+                var evaluatedEnv = manifestManager.EvaluateContainerEnvironment(ExecutionContext, Data.Environment, extraExpressionValues);
                 foreach (var env in evaluatedEnv)
                 {
                     if (!this.Environment.ContainsKey(env.Key))

src/Runner.Worker/Handlers/ScriptHandler.cs

@@ -58,7 +58,16 @@ namespace GitHub.Runner.Worker.Handlers
             string shellCommandPath = null;
             bool validateShellOnHost = !(StepHost is ContainerStepHost);
             string prependPath = string.Join(Path.PathSeparator.ToString(), ExecutionContext.PrependPath.Reverse<string>());
-            Inputs.TryGetValue("shell", out var shell);
+            string shell = null;
+            if (!Inputs.TryGetValue("shell", out shell) || string.IsNullOrEmpty(shell))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    runDefaults.TryGetValue("shell", out shell);
+                }
+            }
             if (string.IsNullOrEmpty(shell))
             {
 #if OS_WINDOWS
@@ -139,11 +148,36 @@ namespace GitHub.Runner.Worker.Handlers
             Inputs.TryGetValue("script", out var contents);
             contents = contents ?? string.Empty;
 
-            Inputs.TryGetValue("workingDirectory", out var workingDirectory);
+            string workingDirectory = null;
+            if (!Inputs.TryGetValue("workingDirectory", out workingDirectory))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    if (runDefaults.TryGetValue("working-directory", out workingDirectory))
+                    {
+                        ExecutionContext.Debug("Overwrite 'working-directory' base on job defaults.");
+                    }
+                }
+            }
             var workspaceDir = githubContext["workspace"] as StringContextData;
             workingDirectory = Path.Combine(workspaceDir, workingDirectory ?? string.Empty);
 
-            Inputs.TryGetValue("shell", out var shell);
+            string shell = null;
+            if (!Inputs.TryGetValue("shell", out shell) || string.IsNullOrEmpty(shell))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    if (runDefaults.TryGetValue("shell", out shell))
+                    {
+                        ExecutionContext.Debug("Overwrite 'shell' base on job defaults.");
+                    }
+                }
+            }
+
             var isContainerStepHost = StepHost is ContainerStepHost;
 
             string prependPath = string.Join(Path.PathSeparator.ToString(), ExecutionContext.PrependPath.Reverse<string>());

src/Runner.Worker/JobExtension.cs

@@ -132,7 +132,7 @@ namespace GitHub.Runner.Worker
                     var templateEvaluator = context.ToPipelineTemplateEvaluator();
                     foreach (var token in message.EnvironmentVariables)
                     {
-                        var environmentVariables = templateEvaluator.EvaluateStepEnvironment(token, jobContext.ExpressionValues, VarUtil.EnvironmentVariableKeyComparer);
+                        var environmentVariables = templateEvaluator.EvaluateStepEnvironment(token, jobContext.ExpressionValues, jobContext.ExpressionFunctions, VarUtil.EnvironmentVariableKeyComparer);
                         foreach (var pair in environmentVariables)
                         {
                             context.EnvironmentVariables[pair.Key] = pair.Value ?? string.Empty;
@@ -142,7 +142,7 @@ namespace GitHub.Runner.Worker
 
                     // Evaluate the job container
                     context.Debug("Evaluating job container");
-                    var container = templateEvaluator.EvaluateJobContainer(message.JobContainer, jobContext.ExpressionValues);
+                    var container = templateEvaluator.EvaluateJobContainer(message.JobContainer, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
                     if (container != null)
                     {
                         jobContext.Container = new Container.ContainerInfo(HostContext, container);
@@ -150,7 +150,7 @@ namespace GitHub.Runner.Worker
 
                     // Evaluate the job service containers
                     context.Debug("Evaluating job service containers");
-                    var serviceContainers = templateEvaluator.EvaluateJobServiceContainers(message.JobServiceContainers, jobContext.ExpressionValues);
+                    var serviceContainers = templateEvaluator.EvaluateJobServiceContainers(message.JobServiceContainers, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
                     if (serviceContainers?.Count > 0)
                     {
                         foreach (var pair in serviceContainers)
@@ -161,6 +161,26 @@ namespace GitHub.Runner.Worker
                         }
                     }
 
+                    // Evaluate the job defaults
+                    context.Debug("Evaluating job defaults");
+                    foreach (var token in message.Defaults)
+                    {
+                        var defaults = token.AssertMapping("defaults");
+                        if (defaults.Any(x => string.Equals(x.Key.AssertString("defaults key").Value, "run", StringComparison.OrdinalIgnoreCase)))
+                        {
+                            context.JobDefaults["run"] = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+                            var defaultsRun = defaults.First(x => string.Equals(x.Key.AssertString("defaults key").Value, "run", StringComparison.OrdinalIgnoreCase));
+                            var jobDefaults = templateEvaluator.EvaluateJobDefaultsRun(defaultsRun.Value, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
+                            foreach (var pair in jobDefaults)
+                            {
+                                if (!string.IsNullOrEmpty(pair.Value))
+                                {
+                                    context.JobDefaults["run"][pair.Key] = pair.Value;
+                                }
+                            }
+                        }
+                    }
+
                     // Build up 2 lists of steps, pre-job, job
                     // Download actions not already in the cache
                     Trace.Info("Downloading actions");
@@ -317,7 +337,7 @@ namespace GitHub.Runner.Worker
                             context.ExpressionValues["steps"] = context.StepsContext.GetScope(context.ScopeName);
 
                             var templateEvaluator = context.ToPipelineTemplateEvaluator();
-                            var outputs = templateEvaluator.EvaluateJobOutput(message.JobOutputs, context.ExpressionValues);
+                            var outputs = templateEvaluator.EvaluateJobOutput(message.JobOutputs, context.ExpressionValues, context.ExpressionFunctions);
                             foreach (var output in outputs)
                             {
                                 if (string.IsNullOrEmpty(output.Value))

src/Runner.Worker/StepsRunner.cs

@@ -1,8 +1,6 @@
-using GitHub.DistributedTask.WebApi;
-using Pipelines = GitHub.DistributedTask.Pipelines;
-using GitHub.Runner.Common.Util;
 using System;
 using System.Collections.Generic;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using GitHub.DistributedTask.Expressions2;
@@ -10,8 +8,13 @@ using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Expressions;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using Pipelines = GitHub.DistributedTask.Pipelines;
 
 namespace GitHub.Runner.Worker
 {
@@ -63,11 +66,7 @@ namespace GitHub.Runner.Worker
                 }
 
                 var step = jobContext.JobSteps.Dequeue();
-                IStep nextStep = null;
-                if (jobContext.JobSteps.Count > 0)
-                {
-                    nextStep = jobContext.JobSteps.Peek();
-                }
+                var nextStep = jobContext.JobSteps.Count > 0 ? jobContext.JobSteps.Peek() : null;
 
                 Trace.Info($"Processing step: DisplayName='{step.DisplayName}'");
                 ArgUtil.NotNull(step.ExecutionContext, nameof(step.ExecutionContext));
@@ -76,6 +75,13 @@ namespace GitHub.Runner.Worker
                 // Start
                 step.ExecutionContext.Start();
 
+                // Expression functions
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<AlwaysFunction>(PipelineTemplateConstants.Always, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<CancelledFunction>(PipelineTemplateConstants.Cancelled, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<FailureFunction>(PipelineTemplateConstants.Failure, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<SuccessFunction>(PipelineTemplateConstants.Success, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<HashFilesFunction>(PipelineTemplateConstants.HashFiles, 1, byte.MaxValue));
+
                 // Initialize scope
                 if (InitializeScope(step, scopeInputs))
                 {
@@ -99,14 +105,13 @@ namespace GitHub.Runner.Worker
 
                         // Evaluate and merge action's env block to env context
                         var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator();
-                        var actionEnvironment = templateEvaluator.EvaluateStepEnvironment(actionStep.Action.Environment, step.ExecutionContext.ExpressionValues, VarUtil.EnvironmentVariableKeyComparer);
+                        var actionEnvironment = templateEvaluator.EvaluateStepEnvironment(actionStep.Action.Environment, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, VarUtil.EnvironmentVariableKeyComparer);
                         foreach (var env in actionEnvironment)
                         {
                             envContext[env.Key] = new StringContextData(env.Value ?? string.Empty);
                         }
                     }
 
-                    var expressionManager = HostContext.GetService<IExpressionManager>();
                     try
                     {
                         // Register job cancellation call back only if job cancellation token not been fire before each step run
@@ -120,28 +125,29 @@ namespace GitHub.Runner.Worker
                                 jobContext.JobContext.Status = jobContext.Result?.ToActionResult();
 
                                 step.ExecutionContext.Debug($"Re-evaluate condition on job cancellation for step: '{step.DisplayName}'.");
-                                ConditionResult conditionReTestResult;
+                                var conditionReTestTraceWriter = new ConditionTraceWriter(Trace, null); // host tracing only
+                                var conditionReTestResult = false;
                                 if (HostContext.RunnerShutdownToken.IsCancellationRequested)
                                 {
                                     step.ExecutionContext.Debug($"Skip Re-evaluate condition on runner shutdown.");
-                                    conditionReTestResult = false;
                                 }
                                 else
                                 {
                                     try
                                     {
-                                        conditionReTestResult = expressionManager.Evaluate(step.ExecutionContext, step.Condition, hostTracingOnly: true);
+                                        var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator(conditionReTestTraceWriter);
+                                        var condition = new BasicExpressionToken(null, null, null, step.Condition);
+                                        conditionReTestResult = templateEvaluator.EvaluateStepIf(condition, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, step.ExecutionContext.ToExpressionState());
                                     }
                                     catch (Exception ex)
                                     {
                                         // Cancel the step since we get exception while re-evaluate step condition.
                                         Trace.Info("Caught exception from expression when re-test condition on job cancellation.");
                                         step.ExecutionContext.Error(ex);
-                                        conditionReTestResult = false;
                                     }
                                 }
 
-                                if (!conditionReTestResult.Value)
+                                if (!conditionReTestResult)
                                 {
                                     // Cancel the step.
                                     Trace.Info("Cancel current running step.");
@@ -161,34 +167,35 @@ namespace GitHub.Runner.Worker
 
                         // Evaluate condition.
                         step.ExecutionContext.Debug($"Evaluating condition for step: '{step.DisplayName}'");
-                        Exception conditionEvaluateError = null;
-                        ConditionResult conditionResult;
+                        var conditionTraceWriter = new ConditionTraceWriter(Trace, step.ExecutionContext);
+                        var conditionResult = false;
+                        var conditionEvaluateError = default(Exception);
                         if (HostContext.RunnerShutdownToken.IsCancellationRequested)
                         {
                             step.ExecutionContext.Debug($"Skip evaluate condition on runner shutdown.");
-                            conditionResult = false;
                         }
                         else
                         {
                             try
                             {
-                                conditionResult = expressionManager.Evaluate(step.ExecutionContext, step.Condition);
+                                var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator(conditionTraceWriter);
+                                var condition = new BasicExpressionToken(null, null, null, step.Condition);
+                                conditionResult = templateEvaluator.EvaluateStepIf(condition, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, step.ExecutionContext.ToExpressionState());
                             }
                             catch (Exception ex)
                             {
                                 Trace.Info("Caught exception from expression.");
                                 Trace.Error(ex);
-                                conditionResult = false;
                                 conditionEvaluateError = ex;
                             }
                         }
 
                         // no evaluate error but condition is false
-                        if (!conditionResult.Value && conditionEvaluateError == null)
+                        if (!conditionResult && conditionEvaluateError == null)
                         {
                             // Condition == false
                             Trace.Info("Skipping step due to condition evaluation.");
-                            CompleteStep(step, nextStep, TaskResult.Skipped, resultCode: conditionResult.Trace);
+                            CompleteStep(step, nextStep, TaskResult.Skipped, resultCode: conditionTraceWriter.Trace);
                         }
                         else if (conditionEvaluateError != null)
                         {
@@ -248,7 +255,7 @@ namespace GitHub.Runner.Worker
             var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator();
             try
             {
-                timeoutMinutes = templateEvaluator.EvaluateStepTimeout(step.Timeout, step.ExecutionContext.ExpressionValues);
+                timeoutMinutes = templateEvaluator.EvaluateStepTimeout(step.Timeout, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions);
             }
             catch (Exception ex)
             {
@@ -339,7 +346,7 @@ namespace GitHub.Runner.Worker
                 var continueOnError = false;
                 try
                 {
-                    continueOnError = templateEvaluator.EvaluateStepContinueOnError(step.ContinueOnError, step.ExecutionContext.ExpressionValues);
+                    continueOnError = templateEvaluator.EvaluateStepContinueOnError(step.ContinueOnError, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions);
                 }
                 catch (Exception ex)
                 {
@@ -392,7 +399,7 @@ namespace GitHub.Runner.Worker
                     var inputs = default(DictionaryContextData);
                     try
                     {
-                        inputs = templateEvaluator.EvaluateStepScopeInputs(scope.Inputs, executionContext.ExpressionValues);
+                        inputs = templateEvaluator.EvaluateStepScopeInputs(scope.Inputs, executionContext.ExpressionValues, executionContext.ExpressionFunctions);
                     }
                     catch (Exception ex)
                     {
@@ -448,7 +455,7 @@ namespace GitHub.Runner.Worker
                     var outputs = default(DictionaryContextData);
                     try
                     {
-                        outputs = templateEvaluator.EvaluateStepScopeOutputs(scope.Outputs, executionContext.ExpressionValues);
+                        outputs = templateEvaluator.EvaluateStepScopeOutputs(scope.Outputs, executionContext.ExpressionValues, executionContext.ExpressionFunctions);
                     }
                     catch (Exception ex)
                     {
@@ -476,5 +483,43 @@ namespace GitHub.Runner.Worker
 
             executionContext.Complete(result, resultCode: resultCode);
         }
+
+        private sealed class ConditionTraceWriter : ObjectTemplating::ITraceWriter
+        {
+            private readonly IExecutionContext _executionContext;
+            private readonly Tracing _trace;
+            private readonly StringBuilder _traceBuilder = new StringBuilder();
+
+            public string Trace => _traceBuilder.ToString();
+
+            public ConditionTraceWriter(Tracing trace, IExecutionContext executionContext)
+            {
+                ArgUtil.NotNull(trace, nameof(trace));
+                _trace = trace;
+                _executionContext = executionContext;
+            }
+
+            public void Error(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Error(message);
+                _executionContext?.Debug(message);
+            }
+
+            public void Info(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Info(message);
+                _executionContext?.Debug(message);
+                _traceBuilder.AppendLine(message);
+            }
+
+            public void Verbose(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Verbose(message);
+                _executionContext?.Debug(message);
+            }
+        }
     }
 }

src/Runner.Worker/action_yaml.json

@@ -91,7 +91,8 @@
                 "strategy",
                 "matrix",
                 "job",
-                "runner"
+                "runner",
+                "hashFiles(1,255)"
             ],
             "string": {}
         },

src/Sdk/DTExpressions2/Expressions2/ExpressionConstants.cs

@@ -5,7 +5,7 @@ using GitHub.DistributedTask.Expressions2.Sdk.Functions;
 
 namespace GitHub.DistributedTask.Expressions2
 {
-    public static class ExpressionConstants
+    internal static class ExpressionConstants
     {
         static ExpressionConstants()
         {
@@ -16,7 +16,6 @@ namespace GitHub.DistributedTask.Expressions2
             AddFunction<StartsWith>("startsWith", 2, 2);
             AddFunction<ToJson>("toJson", 1, 1);
             AddFunction<FromJson>("fromJson", 1, 1);
-            AddFunction<HashFiles>("hashFiles", 1, 1);
         }
 
         private static void AddFunction<T>(String name, Int32 minParameters, Int32 maxParameters)
@@ -25,12 +24,6 @@ namespace GitHub.DistributedTask.Expressions2
             WellKnownFunctions.Add(name, new FunctionInfo<T>(name, minParameters, maxParameters));
         }
 
-        public static void UpdateFunction<T>(String name, Int32 minParameters, Int32 maxParameters)
-                    where T : Function, new()
-        {
-            WellKnownFunctions[name] = new FunctionInfo<T>(name, minParameters, maxParameters);
-        }
-
         internal static readonly String False = "false";
         internal static readonly String Infinity = "Infinity";
         internal static readonly Int32 MaxDepth = 50;

src/Sdk/DTExpressions2/Expressions2/Sdk/Functions/HashFiles.cs

@@ -1,122 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using Minimatch;
-using System.IO;
-using System.Security.Cryptography;
-using GitHub.DistributedTask.Expressions2.Sdk;
-using GitHub.DistributedTask.Pipelines.ContextData;
-using GitHub.DistributedTask.Pipelines.ObjectTemplating;
-namespace GitHub.DistributedTask.Expressions2.Sdk.Functions
-{
-    internal sealed class HashFiles : Function
-    {
-        protected sealed override Object EvaluateCore(
-            EvaluationContext context,
-            out ResultMemory resultMemory)
-        {
-            resultMemory = null;
-
-            // hashFiles() only works on the runner and only works with files under GITHUB_WORKSPACE
-            // Since GITHUB_WORKSPACE is set by runner, I am using that as the fact of this code runs on server or runner.
-            if (context.State is ObjectTemplating.TemplateContext templateContext &&
-                templateContext.ExpressionValues.TryGetValue(PipelineTemplateConstants.GitHub, out var githubContextData) &&
-                githubContextData is DictionaryContextData githubContext &&
-                githubContext.TryGetValue(PipelineTemplateConstants.Workspace, out var workspace) == true &&
-                workspace is StringContextData workspaceData)
-            {
-                string searchRoot = workspaceData.Value;
-                string pattern = Parameters[0].Evaluate(context).ConvertToString();
-
-                // Convert slashes on Windows
-                if (s_isWindows)
-                {
-                    pattern = pattern.Replace('\\', '/');
-                }
-
-                // Root the pattern
-                if (!Path.IsPathRooted(pattern))
-                {
-                    var patternRoot = s_isWindows ? searchRoot.Replace('\\', '/').TrimEnd('/') : searchRoot.TrimEnd('/');
-                    pattern = string.Concat(patternRoot, "/", pattern);
-                }
-
-                // Get all files
-                context.Trace.Info($"Search root directory: '{searchRoot}'");
-                context.Trace.Info($"Search pattern: '{pattern}'");
-                var files = Directory.GetFiles(searchRoot, "*", SearchOption.AllDirectories)
-                    .Select(x => s_isWindows ? x.Replace('\\', '/') : x)
-                    .OrderBy(x => x, StringComparer.Ordinal)
-                    .ToList();
-                if (files.Count == 0)
-                {
-                    throw new ArgumentException($"hashFiles('{ExpressionUtility.StringEscape(pattern)}') failed. Directory '{searchRoot}' is empty");
-                }
-                else
-                {
-                    context.Trace.Info($"Found {files.Count} files");
-                }
-
-                // Match
-                var matcher = new Minimatcher(pattern, s_minimatchOptions);
-                files = matcher.Filter(files)
-                    .Select(x => s_isWindows ? x.Replace('/', '\\') : x)
-                    .ToList();
-                if (files.Count == 0)
-                {
-                    throw new ArgumentException($"hashFiles('{ExpressionUtility.StringEscape(pattern)}') failed. Search pattern '{pattern}' doesn't match any file under '{searchRoot}'");
-                }
-                else
-                {
-                    context.Trace.Info($"{files.Count} matches to hash");
-                }
-
-                // Hash each file
-                List<byte> filesSha256 = new List<byte>();
-                foreach (var file in files)
-                {
-                    context.Trace.Info($"Hash {file}");
-                    using (SHA256 sha256hash = SHA256.Create())
-                    {
-                        using (var fileStream = File.OpenRead(file))
-                        {
-                            filesSha256.AddRange(sha256hash.ComputeHash(fileStream));
-                        }
-                    }
-                }
-
-                // Hash the hashes
-                using (SHA256 sha256hash = SHA256.Create())
-                {
-                    var hashBytes = sha256hash.ComputeHash(filesSha256.ToArray());
-                    StringBuilder hashString = new StringBuilder();
-                    for (int i = 0; i < hashBytes.Length; i++)
-                    {
-                        hashString.Append(hashBytes[i].ToString("x2"));
-                    }
-                    var result = hashString.ToString();
-                    context.Trace.Info($"Final hash result: '{result}'");
-                    return result;
-                }
-            }
-            else
-            {
-                throw new InvalidOperationException("'hashfiles' expression function is only supported under runner context.");
-            }
-        }
-
-        private static readonly bool s_isWindows = Environment.OSVersion.Platform != PlatformID.Unix && Environment.OSVersion.Platform != PlatformID.MacOSX;
-
-        // Only support basic globbing (* ? and []) and globstar (**)
-        private static readonly Options s_minimatchOptions = new Options
-        {
-            Dot = true,
-            NoBrace = true,
-            NoCase = s_isWindows,
-            NoComment = true,
-            NoExt = true,
-            NoNegate = true,
-        };
-    }
-}

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/Definition.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
 
@@ -22,10 +23,27 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
                 {
                     var context = definition[i].Value.AssertSequence($"{TemplateConstants.Context}");
                     definition.RemoveAt(i);
-                    Context = context
-                        .Select(x => x.AssertString($"{TemplateConstants.Context} item").Value)
-                        .Distinct()
-                        .ToArray();
+                    var readerContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                    var evaluatorContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                    foreach (TemplateToken item in context)
+                    {
+                        var itemStr = item.AssertString($"{TemplateConstants.Context} item").Value;
+                        readerContext.Add(itemStr);
+
+                        // Remove min/max parameter info
+                        var paramIndex = itemStr.IndexOf('(');
+                        if (paramIndex > 0)
+                        {
+                            evaluatorContext.Add(String.Concat(itemStr.Substring(0, paramIndex + 1), ")"));
+                        }
+                        else
+                        {
+                            evaluatorContext.Add(itemStr);
+                        }
+                    }
+
+                    ReaderContext = readerContext.ToArray();
+                    EvaluatorContext = evaluatorContext.ToArray();
                 }
                 else if (String.Equals(definitionKey.Value, TemplateConstants.Description, StringComparison.Ordinal))
                 {
@@ -40,7 +58,17 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
 
         internal abstract DefinitionType DefinitionType { get; }
 
-        internal String[] Context { get; private set; } = new String[0];
+        /// <summary>
+        /// Used by the template reader to determine allowed expression values and functions.
+        /// Also used by the template reader to validate function min/max parameters.
+        /// </summary>
+        internal String[] ReaderContext { get; private set; } = new String[0];
+
+        /// <summary>
+        /// Used by the template evaluator to determine allowed expression values and functions.
+        /// The min/max parameter info is omitted.
+        /// </summary>
+        internal String[] EvaluatorContext { get; private set; } = new String[0];
 
         internal abstract void Validate(
             TemplateSchema schema,

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/MappingDefinition.cs

@@ -108,7 +108,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
             {
                 var inherited = schema.GetDefinition(Inherits);
 
-                if (inherited.Context.Length > 0)
+                if (inherited.ReaderContext.Length > 0)
                 {
                     throw new NotSupportedException($"Property '{TemplateConstants.Context}' is not supported on inhertied definitions");
                 }

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/OneOfDefinition.cs

@@ -62,7 +62,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
             {
                 var nestedDefinition = schema.GetDefinition(nestedType);
 
-                if (nestedDefinition.Context.Length > 0)
+                if (nestedDefinition.ReaderContext.Length > 0)
                 {
                     throw new ArgumentException($"'{name}' is a one-of definition and references another definition that defines context. This is currently not supported.");
                 }

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateEvaluator.cs

@@ -47,7 +47,16 @@ namespace GitHub.DistributedTask.ObjectTemplating
             var evaluator = new TemplateEvaluator(context, template, removeBytes);
             try
             {
-                var availableContext = new HashSet<String>(context.ExpressionValues.Keys.Concat(context.ExpressionFunctions.Select(x => $"{x.Name}({x.MinParameters},{x.MaxParameters})")));
+                var availableContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                foreach (var key in context.ExpressionValues.Keys)
+                {
+                    availableContext.Add(key);
+                }
+                foreach (var function in context.ExpressionFunctions)
+                {
+                    availableContext.Add($"{function.Name}()");
+                }
+
                 var definitionInfo = new DefinitionInfo(context.Schema, type, availableContext);
                 result = evaluator.Evaluate(definitionInfo);
 
@@ -393,14 +402,13 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 Definition = m_schema.GetDefinition(name);
 
                 // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                m_allowedContext = Definition.EvaluatorContext;
+                if (Definition.EvaluatorContext.Length > 0)
                 {
-                    m_allowedContext = Definition.Context;
                     Expand = m_availableContext.IsSupersetOf(m_allowedContext);
                 }
                 else
                 {
-                    m_allowedContext = new String[0];
                     Expand = false;
                 }
             }
@@ -416,9 +424,9 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 Definition = m_schema.GetDefinition(name);
 
                 // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                if (Definition.EvaluatorContext.Length > 0)
                 {
-                    m_allowedContext = new HashSet<String>(parent.m_allowedContext.Concat(Definition.Context)).ToArray();
+                    m_allowedContext = new HashSet<String>(parent.m_allowedContext.Concat(Definition.EvaluatorContext), StringComparer.OrdinalIgnoreCase).ToArray();
                     Expand = m_availableContext.IsSupersetOf(m_allowedContext);
                 }
                 else

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateException.cs

@@ -49,6 +49,14 @@ namespace GitHub.DistributedTask.ObjectTemplating
             m_errors = new List<TemplateValidationError>(errors ?? Enumerable.Empty<TemplateValidationError>());
         }
 
+        public TemplateValidationException(
+            String message,
+            IEnumerable<TemplateValidationError> errors)
+            : this(message)
+        {
+            m_errors = new List<TemplateValidationError>(errors ?? Enumerable.Empty<TemplateValidationError>());
+        }
+
         public TemplateValidationException(String message)
             : base(message)
         {

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateReader.cs

@@ -780,15 +780,8 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 // Lookup the definition
                 Definition = m_schema.GetDefinition(name);
 
-                // Determine whether to expand
-                if (Definition.Context.Length > 0)
-                {
-                    AllowedContext = Definition.Context;
-                }
-                else
-                {
-                    AllowedContext = new String[0];
-                }
+                // Record allowed context
+                AllowedContext = Definition.ReaderContext;
             }
 
             public DefinitionInfo(
@@ -800,10 +793,10 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 // Lookup the definition
                 Definition = m_schema.GetDefinition(name);
 
-                // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                // Record allowed context
+                if (Definition.ReaderContext.Length > 0)
                 {
-                    AllowedContext = new HashSet<String>(parent.AllowedContext.Concat(Definition.Context)).ToArray();
+                    AllowedContext = new HashSet<String>(parent.AllowedContext.Concat(Definition.ReaderContext), StringComparer.OrdinalIgnoreCase).ToArray();
                 }
                 else
                 {

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateValidationErrors.cs

@@ -2,6 +2,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Linq;
 using System.Runtime.Serialization;
 
 namespace GitHub.DistributedTask.ObjectTemplating
@@ -41,7 +42,7 @@ namespace GitHub.DistributedTask.ObjectTemplating
         {
             for (int i = 0; i < 50; i++)
             {
-                String message = !String.IsNullOrEmpty(messagePrefix) ? $"{messagePrefix} {ex.Message}" : ex.Message;
+                String message = !String.IsNullOrEmpty(messagePrefix) ? $"{messagePrefix} {ex.Message}" : ex.ToString();
                 Add(new TemplateValidationError(message));
                 if (ex.InnerException == null)
                 {
@@ -88,6 +89,23 @@ namespace GitHub.DistributedTask.ObjectTemplating
             }
         }
 
+        /// <summary>
+        /// Throws <c ref="TemplateValidationException" /> if any errors.
+        /// <param name="prefix">The error message prefix</param>
+        /// </summary>
+        public void Check(String prefix)
+        {
+            if (String.IsNullOrEmpty(prefix))
+            {
+                this.Check();
+            }
+            else if (m_errors.Count > 0)
+            {
+                var message = $"{prefix.Trim()} {String.Join(",", m_errors.Select(e => e.Message))}";
+                throw new TemplateValidationException(message, m_errors);
+            }
+        }
+
         public void Clear()
         {
             m_errors.Clear();

src/Sdk/DTObjectTemplating/ObjectTemplating/Tokens/ExpressionToken.cs

@@ -1,7 +1,9 @@
 using System;
+using System.Collections.Generic;
 using System.ComponentModel;
-using System.Linq;
+using System.Globalization;
 using System.Runtime.Serialization;
+using System.Text.RegularExpressions;
 using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Expressions2.Sdk;
 using GitHub.Services.WebApi.Internal;
@@ -35,11 +37,29 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             String[] allowedContext,
             out Exception ex)
         {
-            // Create dummy allowed contexts
-            INamedValueInfo[] namedValues = null;
+            // Create dummy named values and functions
+            var namedValues = new List<INamedValueInfo>();
+            var functions = new List<IFunctionInfo>();
             if (allowedContext?.Length > 0)
             {
-                namedValues = allowedContext.Select(x => new NamedValueInfo<ContextValueNode>(x)).ToArray();
+                foreach (var contextItem in allowedContext)
+                {
+                    var match = s_function.Match(contextItem);
+                    if (match.Success)
+                    {
+                        var functionName = match.Groups[1].Value;
+                        var minParameters = Int32.Parse(match.Groups[2].Value, NumberStyles.None, CultureInfo.InvariantCulture);
+                        var maxParametersRaw = match.Groups[3].Value;
+                        var maxParameters = String.Equals(maxParametersRaw, TemplateConstants.MaxConstant, StringComparison.Ordinal)
+                            ? Int32.MaxValue
+                            : Int32.Parse(maxParametersRaw, NumberStyles.None, CultureInfo.InvariantCulture);
+                        functions.Add(new FunctionInfo<DummyFunction>(functionName, minParameters, maxParameters));
+                    }
+                    else
+                    {
+                        namedValues.Add(new NamedValueInfo<ContextValueNode>(contextItem));
+                    }
+                }
             }
 
             // Parse
@@ -47,7 +67,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             ExpressionNode root = null;
             try
             {
-                root = new ExpressionParser().CreateTree(expression, null, namedValues, null) as ExpressionNode;
+                root = new ExpressionParser().CreateTree(expression, null, namedValues, functions) as ExpressionNode;
 
                 result = true;
                 ex = null;
@@ -60,5 +80,18 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
 
             return result;
         }
+
+        private sealed class DummyFunction : Function
+        {
+            protected override Object EvaluateCore(
+                EvaluationContext context,
+                out ResultMemory resultMemory)
+            {
+                resultMemory = null;
+                return null;
+            }
+        }
+
+        private static readonly Regex s_function = new Regex(@"^([a-zA-Z0-9_]+)\(([0-9]+),([0-9]+|MAX)\)$", RegexOptions.Compiled);
     }
 }

src/Sdk/DTObjectTemplating/ObjectTemplating/Tokens/TemplateTokenExtensions.cs

@@ -1,5 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
 
 namespace GitHub.DistributedTask.ObjectTemplating.Tokens
 {
@@ -106,6 +109,43 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             throw new ArgumentException($"Error while reading '{objectDescription}'. Unexpected value '{literal.ToString()}'");
         }
 
+        /// <summary>
+        /// Traverses the token and checks whether all required expression values
+        /// and functions are provided.
+        /// </summary>
+        public static bool CheckHasRequiredContext(
+            this TemplateToken token,
+            IReadOnlyObject expressionValues,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var expressionTokens = token.Traverse()
+                .OfType<BasicExpressionToken>()
+                .ToArray();
+            var parser = new ExpressionParser();
+            foreach (var expressionToken in expressionTokens)
+            {
+                var tree = parser.ValidateSyntax(expressionToken.Expression, null);
+                foreach (var node in tree.Traverse())
+                {
+                    if (node is NamedValue namedValue)
+                    {
+                        if (expressionValues?.Keys.Any(x => string.Equals(x, namedValue.Name, StringComparison.OrdinalIgnoreCase)) != true)
+                        {
+                            return false;
+                        }
+                    }
+                    else if (node is Function function &&
+                        !ExpressionConstants.WellKnownFunctions.ContainsKey(function.Name) &&
+                        expressionFunctions?.Any(x => string.Equals(x.Name, function.Name, StringComparison.OrdinalIgnoreCase)) != true)
+                    {
+                        return false;
+                    }
+                }
+            }
+
+            return true;
+        }
+
         /// <summary>
         /// Returns all tokens (depth first)
         /// </summary>

src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs

@@ -41,7 +41,8 @@ namespace GitHub.DistributedTask.Pipelines
             IEnumerable<JobStep> steps,
             IEnumerable<ContextScope> scopes,
             IList<String> fileTable,
-            TemplateToken jobOutputs)
+            TemplateToken jobOutputs,
+            IList<TemplateToken> defaults)
         {
             this.MessageType = JobRequestMessageTypes.PipelineAgentJobRequest;
             this.Plan = plan;
@@ -69,6 +70,11 @@ namespace GitHub.DistributedTask.Pipelines
                 m_environmentVariables = new List<TemplateToken>(environmentVariables);
             }
 
+            if (defaults?.Count > 0)
+            {
+                m_defaults = new List<TemplateToken>(defaults);
+            }
+
             this.ContextData = new Dictionary<String, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
             if (contextData?.Count > 0)
             {
@@ -213,6 +219,21 @@ namespace GitHub.DistributedTask.Pipelines
             }
         }
 
+        /// <summary>
+        /// Gets the hierarchy of defaults to overlay, last wins.
+        /// </summary>
+        public IList<TemplateToken> Defaults
+        {
+            get
+            {
+                if (m_defaults == null)
+                {
+                    m_defaults = new List<TemplateToken>();
+                }
+                return m_defaults;
+            }
+        }
+
         /// <summary>
         /// Gets the collection of variables associated with the current context.
         /// </summary>
@@ -252,6 +273,9 @@ namespace GitHub.DistributedTask.Pipelines
             }
         }
 
+        /// <summary>
+        /// Gets the table of files used when parsing the pipeline (e.g. yaml files)
+        /// </summary>
         public IList<String> FileTable
         {
             get
@@ -372,6 +396,11 @@ namespace GitHub.DistributedTask.Pipelines
                 m_environmentVariables = null;
             }
 
+            if (m_defaults?.Count == 0)
+            {
+                m_defaults = null;
+            }
+
             if (m_fileTable?.Count == 0)
             {
                 m_fileTable = null;
@@ -406,6 +435,9 @@ namespace GitHub.DistributedTask.Pipelines
         [DataMember(Name = "EnvironmentVariables", EmitDefaultValue = false)]
         private List<TemplateToken> m_environmentVariables;
 
+        [DataMember(Name = "Defaults", EmitDefaultValue = false)]
+        private List<TemplateToken> m_defaults;
+
         [DataMember(Name = "FileTable", EmitDefaultValue = false)]
         private List<String> m_fileTable;
 

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

@@ -14,6 +14,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         public const String Clean = "clean";
         public const String Container = "container";
         public const String ContinueOnError = "continue-on-error";
+        public const String Defaults = "defaults";
         public const String Env = "env";
         public const String Event = "event";
         public const String EventPattern = "github.event";
@@ -23,12 +24,15 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         public const String FetchDepth = "fetch-depth";
         public const String GeneratedId = "generated-id";
         public const String GitHub = "github";
+        public const String HashFiles = "hashFiles";
         public const String Id = "id";
         public const String If = "if";
         public const String Image = "image";
         public const String Include = "include";
         public const String Inputs = "inputs";
         public const String Job = "job";
+        public const String JobDefaultsRun = "job-defaults-run";
+        public const String JobIfResult = "job-if-result";
         public const String JobOutputs = "job-outputs";
         public const String Jobs = "jobs";
         public const String Labels = "labels";
@@ -58,6 +62,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         public const String Shell = "shell";
         public const String Skipped = "skipped";
         public const String StepEnv = "step-env";
+        public const String StepIfResult = "step-if-result";
         public const String Steps = "steps";
         public const String StepsScopeInputs = "steps-scope-inputs";
         public const String StepsScopeOutputs = "steps-scope-outputs";

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

@@ -16,6 +16,20 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
     internal static class PipelineTemplateConverter
     {
+        internal static Boolean ConvertToIfResult(
+            TemplateContext context,
+            TemplateToken ifResult)
+        {
+            var expression = ifResult.Traverse().FirstOrDefault(x => x is ExpressionToken);
+            if (expression != null)
+            {
+                throw new ArgumentException($"Unexpected type '{expression.GetType().Name}' encountered while reading 'if'.");
+            }
+
+            var evaluationResult = EvaluationResult.CreateIntermediateResult(null, ifResult);
+            return evaluationResult.IsTruthy;
+        }
+
         internal static Boolean? ConvertToStepContinueOnError(
             TemplateContext context,
             TemplateToken token,

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

@@ -4,7 +4,7 @@ using System.ComponentModel;
 using System.Linq;
 using System.Threading;
 using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.Expressions2.Sdk.Functions;
 using GitHub.DistributedTask.ObjectTemplating;
 using GitHub.DistributedTask.ObjectTemplating.Schema;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
@@ -14,6 +14,9 @@ using ITraceWriter = GitHub.DistributedTask.ObjectTemplating.ITraceWriter;
 
 namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
+    /// <summary>
+    /// Evaluates parts of the workflow DOM. For example, a job strategy or step inputs.
+    /// </summary>
     [EditorBrowsable(EditorBrowsableState.Never)]
     public class PipelineTemplateEvaluator
     {
@@ -50,13 +53,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public DictionaryContextData EvaluateStepScopeInputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(DictionaryContextData);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepsScopeInputs, token, 0, null, omitHeader: true);
@@ -76,13 +80,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public DictionaryContextData EvaluateStepScopeOutputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(DictionaryContextData);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepsScopeOutputs, token, 0, null, omitHeader: true);
@@ -102,13 +107,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Boolean EvaluateStepContinueOnError(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Boolean?);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.BooleanStepsContext, token, 0, null, omitHeader: true);
@@ -126,16 +132,44 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result ?? false;
         }
 
+        public String EvaluateStepDisplayName(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var result = default(String);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StringStepsContext, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = PipelineTemplateConverter.ConvertToStepDisplayName(context, token);
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result;
+        }
+
         public Dictionary<String, String> EvaluateStepEnvironment(
             TemplateToken token,
             DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions,
             StringComparer keyComparer)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepEnv, token, 0, null, omitHeader: true);
@@ -153,15 +187,44 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result ?? new Dictionary<String, String>(keyComparer);
         }
 
+        public Boolean EvaluateStepIf(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions,
+            IEnumerable<KeyValuePair<String, Object>> expressionState)
+        {
+            var result = default(Boolean?);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions, expressionState);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepIfResult, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = PipelineTemplateConverter.ConvertToIfResult(context, token);
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result ?? throw new InvalidOperationException("Step if cannot be null");
+        }
+
         public Dictionary<String, String> EvaluateStepInputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepWith, token, 0, null, omitHeader: true);
@@ -181,13 +244,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Int32 EvaluateStepTimeout(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Int32?);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.NumberStepsContext, token, 0, null, omitHeader: true);
@@ -207,13 +271,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public JobContainer EvaluateJobContainer(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(JobContainer);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.Container, token, 0, null, omitHeader: true);
@@ -233,13 +298,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Dictionary<String, String> EvaluateJobOutput(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.JobOutputs, token, 0, null, omitHeader: true);
@@ -267,15 +333,53 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result;
         }
 
+        public Dictionary<String, String> EvaluateJobDefaultsRun(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var result = default(Dictionary<String, String>);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.JobDefaultsRun, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = new Dictionary<String, String>(StringComparer.OrdinalIgnoreCase);
+                    var mapping = token.AssertMapping("defaults run");
+                    foreach (var pair in mapping)
+                    {
+                        // Literal key
+                        var key = pair.Key.AssertString("defaults run key");
+
+                        // Literal value
+                        var value = pair.Value.AssertString("defaults run value");
+                        result[key.Value] = value.Value;
+                    }
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result;
+        }
+
         public IList<KeyValuePair<String, JobContainer>> EvaluateJobServiceContainers(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(List<KeyValuePair<String, JobContainer>>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.Services, token, 0, null, omitHeader: true);
@@ -293,62 +397,10 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result;
         }
 
-        public Boolean TryEvaluateStepDisplayName(
-            TemplateToken token,
+        private TemplateContext CreateContext(
             DictionaryContextData contextData,
-            out String stepName)
-        {
-            stepName = default(String);
-            var context = CreateContext(contextData);
-
-            if (token != null && token.Type != TokenType.Null)
-            {
-                // We should only evaluate basic expressions if we are sure we have context on all the Named Values and functions
-                // Otherwise return and use a default name
-                if (token is BasicExpressionToken expressionToken)
-                {
-                    ExpressionNode root = null;
-                    try
-                    {
-                        root = new ExpressionParser().ValidateSyntax(expressionToken.Expression, null) as ExpressionNode;
-                    }
-                    catch (Exception exception)
-                    {
-                        context.Errors.Add(exception);
-                        context.Errors.Check();
-                    }
-                    foreach (var node in root.Traverse())
-                    {
-                        if (node is NamedValue namedValue && !contextData.ContainsKey(namedValue.Name))
-                        {
-                            return false;
-                        }
-                        else if (node is Function function &&
-                            !context.ExpressionFunctions.Any(item => String.Equals(item.Name, function.Name)) &&
-                            !ExpressionConstants.WellKnownFunctions.ContainsKey(function.Name))
-                        {
-                            return false;
-                        }
-                    }
-                }
-
-                try
-                {
-                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StringStepsContext, token, 0, null, omitHeader: true);
-                    context.Errors.Check();
-                    stepName = PipelineTemplateConverter.ConvertToStepDisplayName(context, token);
-                }
-                catch (Exception ex) when (!(ex is TemplateValidationException))
-                {
-                    context.Errors.Add(ex);
-                }
-
-                context.Errors.Check();
-            }
-            return true;
-        }
-
-        private TemplateContext CreateContext(DictionaryContextData contextData)
+            IList<IFunctionInfo> expressionFunctions,
+            IEnumerable<KeyValuePair<String, Object>> expressionState = null)
         {
             var result = new TemplateContext
             {
@@ -371,7 +423,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                 }
             }
 
-            // Add named context
+            // Add named values
             if (contextData != null)
             {
                 foreach (var pair in contextData)
@@ -380,14 +432,46 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                 }
             }
 
-            // Compat for new agent against old server
-            foreach (var name in s_contextNames)
+            // Add functions
+            var functionNames = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+            if (expressionFunctions?.Count > 0)
+            {
+                foreach (var function in expressionFunctions)
+                {
+                    result.ExpressionFunctions.Add(function);
+                    functionNames.Add(function.Name);
+                }
+            }
+
+            // Add missing expression values and expression functions.
+            // This solves the following problems:
+            //   - Compat for new agent against old server (new contexts not sent down in job message)
+            //   - Evaluating early when all referenced contexts are available, even though all allowed
+            //     contexts may not yet be available. For example, evaluating step display name can often
+            //     be performed early.
+            foreach (var name in s_expressionValueNames)
             {
                 if (!result.ExpressionValues.ContainsKey(name))
                 {
                     result.ExpressionValues[name] = null;
                 }
             }
+            foreach (var name in s_expressionFunctionNames)
+            {
+                if (!functionNames.Contains(name))
+                {
+                    result.ExpressionFunctions.Add(new FunctionInfo<NoOperation>(name, 0, Int32.MaxValue));
+                }
+            }
+
+            // Add state
+            if (expressionState != null)
+            {
+                foreach (var pair in expressionState)
+                {
+                    result.State[pair.Key] = pair.Value;
+                }
+            }
 
             return result;
         }
@@ -395,9 +479,10 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         private readonly ITraceWriter m_trace;
         private readonly TemplateSchema m_schema;
         private readonly IList<String> m_fileTable;
-        private readonly String[] s_contextNames = new[]
+        private readonly String[] s_expressionValueNames = new[]
         {
             PipelineTemplateConstants.GitHub,
+            PipelineTemplateConstants.Needs,
             PipelineTemplateConstants.Strategy,
             PipelineTemplateConstants.Matrix,
             PipelineTemplateConstants.Needs,
@@ -408,5 +493,13 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             PipelineTemplateConstants.Runner,
             PipelineTemplateConstants.Env,
         };
+        private readonly String[] s_expressionFunctionNames = new[]
+        {
+            PipelineTemplateConstants.Always,
+            PipelineTemplateConstants.Cancelled,
+            PipelineTemplateConstants.Failure,
+            PipelineTemplateConstants.HashFiles,
+            PipelineTemplateConstants.Success,
+        };
     }
 }

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

@@ -2,14 +2,18 @@
 using System.ComponentModel;
 using System.IO;
 using System.Reflection;
+using System.Threading;
+using System.Threading.Tasks;
 using GitHub.DistributedTask.ObjectTemplating.Schema;
 
 namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
     [EditorBrowsable(EditorBrowsableState.Never)]
-    public sealed class PipelineTemplateSchemaFactory
+    public static class PipelineTemplateSchemaFactory
     {
-        public TemplateSchema CreateSchema()
+        public static TemplateSchema GetSchema()
+        {
+            if (s_schema == null)
             {
                 var assembly = Assembly.GetExecutingAssembly();
                 var json = default(String);
@@ -20,7 +24,13 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                 }
 
                 var objectReader = new JsonObjectReader(null, json);
-            return TemplateSchema.Load(objectReader);
-        }
+                var schema = TemplateSchema.Load(objectReader);
+                Interlocked.CompareExchange(ref s_schema, schema, null);
+            }
+
+            return s_schema;
+        }
+
+        private static TemplateSchema s_schema;
     }
 }

src/Sdk/DTPipelines/workflow-v1.0.json

@@ -9,6 +9,7 @@
         "properties": {
           "on": "any",
           "name": "string",
+          "defaults": "workflow-defaults",
           "env": "workflow-env",
           "jobs": "jobs"
         }
@@ -37,8 +38,8 @@
     "steps-scope-input-value": {
       "context": [
         "github",
-        "strategy",
         "needs",
+        "strategy",
         "matrix",
         "secrets",
         "steps",
@@ -65,9 +66,9 @@
     "steps-scope-output-value": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
@@ -90,9 +91,9 @@
       "description": "Default input values for a steps template",
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "string",
@@ -113,9 +114,9 @@
       "description": "Output values for a steps template",
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -125,6 +126,23 @@
       "string": {}
     },
 
+    "workflow-defaults": {
+      "mapping": {
+        "properties": {
+          "run": "workflow-defaults-run"
+        }
+      }
+    },
+
+    "workflow-defaults-run": {
+      "mapping": {
+        "properties": {
+          "shell": "non-empty-string",
+          "working-directory": "non-empty-string"
+        }
+      }
+    },
+
     "workflow-env": {
       "context": [
         "github",
@@ -161,6 +179,7 @@
           "services": "services",
           "env": "job-env",
           "outputs": "job-outputs",
+          "defaults": "job-defaults",
           "steps": "steps"
         }
       }
@@ -185,6 +204,25 @@
       "string": {}
     },
 
+    "job-if-result": {
+      "context": [
+        "github",
+        "needs",
+        "always(0,0)",
+        "failure(0,MAX)",
+        "cancelled(0,0)",
+        "success(0,MAX)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
     "strategy": {
       "context": [
         "github",
@@ -253,9 +291,9 @@
     "runs-on": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "non-empty-string",
@@ -278,10 +316,10 @@
     "job-env": {
       "context": [
         "github",
-        "secrets",
+        "needs",
         "strategy",
         "matrix",
-        "needs"
+        "secrets"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -289,6 +327,30 @@
       }
     },
 
+    "job-defaults": {
+      "mapping": {
+        "properties": {
+          "run": "job-defaults-run"
+        }
+      }
+    },
+
+    "job-defaults-run": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "needs",
+        "env"
+      ],
+      "mapping": {
+        "properties": {
+          "shell": "non-empty-string",
+          "working-directory": "non-empty-string"
+        }
+      }
+    },
+
     "job-outputs": {
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -401,9 +463,9 @@
     "step-if": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "steps",
         "job",
         "runner",
@@ -411,7 +473,8 @@
         "always(0,0)",
         "failure(0,0)",
         "cancelled(0,0)",
-        "success(0,0)"
+        "success(0,0)",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
@@ -419,9 +482,9 @@
     "step-if-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "steps",
         "inputs",
         "job",
@@ -430,11 +493,63 @@
         "always(0,0)",
         "failure(0,0)",
         "cancelled(0,0)",
-        "success(0,0)"
+        "success(0,0)",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
 
+    "step-if-result": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "steps",
+        "job",
+        "runner",
+        "env",
+        "always(0,0)",
+        "failure(0,0)",
+        "cancelled(0,0)",
+        "success(0,0)",
+        "hashFiles(1,255)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
+    "step-if-result-in-template": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "steps",
+        "inputs",
+        "job",
+        "runner",
+        "env",
+        "always(0,0)",
+        "failure(0,0)",
+        "cancelled(0,0)",
+        "success(0,0)",
+        "hashFiles(1,255)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
     "steps-template-reference": {
       "mapping": {
         "properties": {
@@ -458,9 +573,9 @@
     "steps-template-reference-inputs": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -476,9 +591,9 @@
     "steps-template-reference-inputs-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
@@ -495,14 +610,15 @@
     "step-env": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -513,15 +629,16 @@
     "step-env-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -532,14 +649,35 @@
     "step-with": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
+      ],
+      "mapping": {
+        "loose-key-type": "non-empty-string",
+        "loose-value-type": "string"
+      }
+    },
+
+    "step-with-in-template": {
+      "context": [
+        "github",
+        "needs",
+        "strategy",
+        "matrix",
+        "secrets",
+        "steps",
+        "inputs",
+        "job",
+        "runner",
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -550,9 +688,9 @@
     "container": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "string",
@@ -575,9 +713,9 @@
     "services": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -588,9 +726,9 @@
     "services-container": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "non-empty-string",
@@ -605,25 +743,6 @@
       }
     },
 
-    "step-with-in-template": {
-        "context": [
-          "github",
-          "strategy",
-          "matrix",
-          "needs",
-          "secrets",
-          "steps",
-          "inputs",
-          "job",
-          "runner",
-          "env"
-        ],
-        "mapping": {
-          "loose-key-type": "non-empty-string",
-          "loose-value-type": "string"
-        }
-      },
-  
     "non-empty-string": {
       "string": {
         "require-non-empty": true
@@ -639,9 +758,9 @@
     "boolean-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "boolean": {}
     },
@@ -649,9 +768,9 @@
     "number-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "number": {}
     },
@@ -659,9 +778,9 @@
     "string-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "string": {}
     },
@@ -669,14 +788,15 @@
     "boolean-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "boolean": {}
     },
@@ -684,15 +804,16 @@
     "boolean-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "boolean": {}
     },
@@ -700,14 +821,15 @@
     "number-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "number": {}
     },
@@ -715,15 +837,16 @@
     "number-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "number": {}
     },
@@ -731,9 +854,9 @@
     "string-runner-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -746,14 +869,15 @@
     "string-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
@@ -761,15 +885,16 @@
     "string-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "string": {}
     }

src/Test/L0/Listener/JobDispatcherL0.cs

@@ -33,7 +33,7 @@ namespace GitHub.Runner.Common.Tests.Listener
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = null;
             Guid jobId = Guid.NewGuid();
-            var result = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "someJob", "someJob", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            var result = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "someJob", "someJob", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
             result.ContextData["github"] = new Pipelines.ContextData.DictionaryContextData();
             return result;
         }

src/Test/L0/Listener/RunnerL0.cs

@@ -43,7 +43,7 @@ namespace GitHub.Runner.Common.Tests.Listener
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = null;
             Guid jobId = Guid.NewGuid();
-            return new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            return new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
         }
 
         private JobCancelMessage CreateJobCancelMessage()

src/Test/L0/Worker/ActionCommandManagerL0.cs

@@ -150,7 +150,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,

src/Test/L0/Worker/ActionManagerL0.cs

@@ -1,4 +1,6 @@
-using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Worker;
@@ -1600,6 +1602,8 @@ runs:
             _ec = new Mock<IExecutionContext>();
             _ec.Setup(x => x.CancellationToken).Returns(_ecTokenSource.Token);
             _ec.Setup(x => x.Variables).Returns(new Variables(_hc, new Dictionary<string, VariableValue>()));
+            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.Write(It.IsAny<string>(), It.IsAny<string>())).Callback((string tag, string message) => { _hc.GetTrace().Info($"[{tag}]{message}"); });
             _ec.Setup(x => x.AddIssue(It.IsAny<Issue>(), It.IsAny<string>())).Callback((Issue issue, string message) => { _hc.GetTrace().Info($"[{issue.Type}]{issue.Message ?? message}"); });
             _ec.Setup(x => x.GetGitHubContext("workspace")).Returns(Path.Combine(_workFolder, "actions", "actions"));

src/Test/L0/Worker/ActionManifestManagerL0.cs

@@ -1,7 +1,9 @@
+using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Expressions;
 using Moq;
 using System;
 using System.Collections.Generic;
@@ -533,26 +535,26 @@ namespace GitHub.Runner.Common.Tests.Worker
                 var actionManifest = new ActionManifestManager();
                 actionManifest.Initialize(_hc);
 
-                var githubContext = new DictionaryContextData();
-                githubContext.Add("ref", new StringContextData("refs/heads/master"));
-
-                var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-                evaluateContext["github"] = githubContext;
-                evaluateContext["strategy"] = new DictionaryContextData();
-                evaluateContext["matrix"] = new DictionaryContextData();
-                evaluateContext["steps"] = new DictionaryContextData();
-                evaluateContext["job"] = new DictionaryContextData();
-                evaluateContext["runner"] = new DictionaryContextData();
-                evaluateContext["env"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["github"] = new DictionaryContextData
+                {
+                    { "ref", new StringContextData("refs/heads/master") },
+                };
+                _ec.Object.ExpressionValues["strategy"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["matrix"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["steps"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["job"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["runner"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["env"] = new DictionaryContextData();
+                _ec.Object.ExpressionFunctions.Add(new FunctionInfo<HashFilesFunction>("hashFiles", 1, 255));
 
                 //Act
-                var result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new StringToken(null, null, null, "defaultValue"), evaluateContext);
+                var result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new StringToken(null, null, null, "defaultValue"));
 
                 //Assert
                 Assert.Equal("defaultValue", result);
 
                 //Act
-                result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new BasicExpressionToken(null, null, null, "github.ref"), evaluateContext);
+                result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new BasicExpressionToken(null, null, null, "github.ref"));
 
                 //Assert
                 Assert.Equal("refs/heads/master", result);
@@ -575,6 +577,8 @@ namespace GitHub.Runner.Common.Tests.Worker
             _ec.Setup(x => x.WriteDebug).Returns(true);
             _ec.Setup(x => x.CancellationToken).Returns(_ecTokenSource.Token);
             _ec.Setup(x => x.Variables).Returns(new Variables(_hc, new Dictionary<string, VariableValue>()));
+            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.Write(It.IsAny<string>(), It.IsAny<string>())).Callback((string tag, string message) => { _hc.GetTrace().Info($"{tag}{message}"); });
             _ec.Setup(x => x.AddIssue(It.IsAny<Issue>(), It.IsAny<string>())).Callback((Issue issue, string message) => { _hc.GetTrace().Info($"[{issue.Type}]{issue.Message ?? message}"); });
         }

src/Test/L0/Worker/ActionRunnerL0.cs

@@ -1,4 +1,5 @@
-using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
@@ -322,6 +323,7 @@ namespace GitHub.Runner.Common.Tests.Worker
 
             _ec = new Mock<IExecutionContext>();
             _ec.Setup(x => x.ExpressionValues).Returns(_context);
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.IntraActionState).Returns(new Dictionary<string, string>());
             _ec.Setup(x => x.EnvironmentVariables).Returns(new Dictionary<string, string>());
             _ec.Setup(x => x.SetGitHubContext(It.IsAny<string>(), It.IsAny<string>()));

src/Test/L0/Worker/ExecutionContextL0.cs

@@ -25,7 +25,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,
@@ -101,7 +101,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,
@@ -152,7 +152,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,

src/Test/L0/Worker/Expressions/ConditionFunctionsL0.cs

@@ -1,20 +1,20 @@
 using System;
 using System.Collections.Generic;
 using System.Runtime.CompilerServices;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.Pipelines.ObjectTemplating;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Expressions;
 using Moq;
 using Xunit;
-using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Pipelines.ContextData;
 
-namespace GitHub.Runner.Common.Tests.Worker
+namespace GitHub.Runner.Common.Tests.Worker.Expressions
 {
-    public sealed class ExpressionManagerL0
+    public sealed class ConditionFunctionsL0
     {
-        private Mock<IExecutionContext> _ec;
-        private ExpressionManager _expressionManager;
-        private DictionaryContextData _expressions;
+        private TemplateContext _templateContext;
         private JobContext _jobContext;
 
         [Fact]
@@ -38,7 +38,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "always()").Value;
+                    bool actual = Evaluate("always()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -68,7 +68,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "cancelled()").Value;
+                    bool actual = Evaluate("cancelled()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -97,7 +97,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "failure()").Value;
+                    bool actual = Evaluate("failure()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -126,37 +126,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "success()").Value;
-
-                    // Assert.
-                    Assert.Equal(variableSet.Expected, actual);
-                }
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public void ContextNamedValue()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                // Arrange.
-                var variableSets = new[]
-                {
-                    new { Condition = "github.ref == 'refs/heads/master'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github['ref'] == 'refs/heads/master'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github.nosuch || '' == ''", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github['ref'] == 'refs/heads/release'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = false },
-                    new { Condition = "github.ref == 'refs/heads/release'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = false },
-                };
-                foreach (var variableSet in variableSets)
-                {
-                    InitializeExecutionContext(hc);
-                    _ec.Object.ExpressionValues["github"] = new GitHubContext() { { variableSet.VariableName, new StringContextData(variableSet.VariableValue) } };
-
-                    // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, variableSet.Condition).Value;
+                    bool actual = Evaluate("success()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -166,21 +136,34 @@ namespace GitHub.Runner.Common.Tests.Worker
 
         private TestHostContext CreateTestContext([CallerMemberName] String testName = "")
         {
-            var hc = new TestHostContext(this, testName);
-            _expressionManager = new ExpressionManager();
-            _expressionManager.Initialize(hc);
-            return hc;
+            return new TestHostContext(this, testName);
         }
 
         private void InitializeExecutionContext(TestHostContext hc)
         {
-            _expressions = new DictionaryContextData();
             _jobContext = new JobContext();
 
-            _ec = new Mock<IExecutionContext>();
-            _ec.SetupAllProperties();
-            _ec.Setup(x => x.ExpressionValues).Returns(_expressions);
-            _ec.Setup(x => x.JobContext).Returns(_jobContext);
+            var executionContext = new Mock<IExecutionContext>();
+            executionContext.SetupAllProperties();
+            executionContext.Setup(x => x.JobContext).Returns(_jobContext);
+
+            _templateContext = new TemplateContext();
+            _templateContext.State[nameof(IExecutionContext)] = executionContext.Object;
+        }
+
+        private bool Evaluate(string expression)
+        {
+            var parser = new ExpressionParser();
+            var functions = new IFunctionInfo[]
+            {
+                new FunctionInfo<AlwaysFunction>(PipelineTemplateConstants.Always, 0, 0),
+                new FunctionInfo<CancelledFunction>(PipelineTemplateConstants.Cancelled, 0, 0),
+                new FunctionInfo<FailureFunction>(PipelineTemplateConstants.Failure, 0, 0),
+                new FunctionInfo<SuccessFunction>(PipelineTemplateConstants.Success, 0, 0),
+            };
+            var tree = parser.CreateTree(expression, null, null, functions);
+            var result = tree.Evaluate(null, null, _templateContext, null);
+            return result.IsTruthy;
         }
     }
 }

src/Test/L0/Worker/JobExtensionL0.cs

@@ -22,7 +22,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         private Mock<IJobServerQueue> _jobServerQueue;
         private Mock<IConfigurationStore> _config;
         private Mock<IPagingLogger> _logger;
-        private Mock<IExpressionManager> _express;
         private Mock<IContainerOperationProvider> _containerProvider;
         private Mock<IDiagnosticLogManager> _diagnosticLogManager;
 
@@ -35,7 +34,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             _jobServerQueue = new Mock<IJobServerQueue>();
             _config = new Mock<IConfigurationStore>();
             _logger = new Mock<IPagingLogger>();
-            _express = new Mock<IExpressionManager>();
             _containerProvider = new Mock<IContainerOperationProvider>();
             _diagnosticLogManager = new Mock<IDiagnosticLogManager>();
             _directoryManager = new Mock<IPipelineDirectoryManager>();
@@ -100,7 +98,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             };
 
             Guid jobId = Guid.NewGuid();
-            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), steps, null, null, null);
+            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), steps, null, null, null, null);
             GitHubContext github = new GitHubContext();
             github["repository"] = new Pipelines.ContextData.StringContextData("actions/runner");
             _message.ContextData.Add("github", github);
@@ -108,7 +106,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             hc.SetSingleton(_actionManager.Object);
             hc.SetSingleton(_config.Object);
             hc.SetSingleton(_jobServerQueue.Object);
-            hc.SetSingleton(_express.Object);
             hc.SetSingleton(_containerProvider.Object);
             hc.SetSingleton(_directoryManager.Object);
             hc.SetSingleton(_diagnosticLogManager.Object);

src/Test/L0/Worker/JobRunnerL0.cs

@@ -53,9 +53,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             }
 
             _tokenSource = new CancellationTokenSource();
-            var expressionManager = new ExpressionManager();
-            expressionManager.Initialize(hc);
-            hc.SetSingleton<IExpressionManager>(expressionManager);
 
             _jobRunner = new JobRunner();
             _jobRunner.Initialize(hc);
@@ -63,7 +60,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = new Timeline(Guid.NewGuid());
             Guid jobId = Guid.NewGuid();
-            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, testName, testName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, testName, testName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
             _message.Variables[Constants.Variables.System.Culture] = "en-US";
             _message.Resources.Endpoints.Add(new ServiceEndpoint()
             {

src/Test/L0/Worker/StepsRunnerL0.cs

@@ -1,17 +1,17 @@
-using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Worker;
-using Moq;
-using System;
+using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
+using Moq;
 using Xunit;
 using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
+using GitHub.Runner.Worker;
 
 namespace GitHub.Runner.Common.Tests.Worker
 {
@@ -27,9 +27,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         private TestHostContext CreateTestContext([CallerMemberName] String testName = "")
         {
             var hc = new TestHostContext(this, testName);
-            var expressionManager = new ExpressionManager();
-            expressionManager.Initialize(hc);
-            hc.SetSingleton<IExpressionManager>(expressionManager);
             Dictionary<string, VariableValue> variablesToCopy = new Dictionary<string, VariableValue>();
             _variables = new Variables(
                 hostContext: hc,
@@ -49,6 +46,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             _contexts["runner"] = new DictionaryContextData();
             _contexts["job"] = _jobContext;
             _ec.Setup(x => x.ExpressionValues).Returns(_contexts);
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.JobContext).Returns(_jobContext);
 
             _stepContext = new StepsContext();
@@ -383,16 +381,11 @@ namespace GitHub.Runner.Common.Tests.Worker
         {
             using (TestHostContext hc = CreateTestContext())
             {
-                var expressionManager = new Mock<IExpressionManager>();
-                expressionManager.Object.Initialize(hc);
-                hc.SetSingleton<IExpressionManager>(expressionManager.Object);
-                expressionManager.Setup(x => x.Evaluate(It.IsAny<IExecutionContext>(), It.IsAny<string>(), It.IsAny<bool>())).Throws(new Exception());
-
                 // Arrange.
                 var variableSets = new[]
                 {
-                    new[] { CreateStep(hc, TaskResult.Succeeded, "success()") },
-                    new[] { CreateStep(hc, TaskResult.Succeeded, "success()") },
+                    new[] { CreateStep(hc, TaskResult.Succeeded, "fromJson('not json')") },
+                    new[] { CreateStep(hc, TaskResult.Succeeded, "fromJson('not json')") },
                 };
                 foreach (var variableSet in variableSets)
                 {
@@ -610,6 +603,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             stepContext.Setup(x => x.Variables).Returns(_variables);
             stepContext.Setup(x => x.EnvironmentVariables).Returns(_env);
             stepContext.Setup(x => x.ExpressionValues).Returns(_contexts);
+            stepContext.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             stepContext.Setup(x => x.JobContext).Returns(_jobContext);
             stepContext.Setup(x => x.StepsContext).Returns(_stepContext);
             stepContext.Setup(x => x.ContextName).Returns(step.Object.Action.ContextName);

src/Test/L0/Worker/WorkerL0.cs

@@ -67,7 +67,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     new Pipelines.ContextData.DictionaryContextData()
                 },
             };
-            var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, JobId, jobName, jobName, new StringToken(null, null, null, "ubuntu"), sidecarContainers, null, variables, new List<MaskHint>(), resources, context, null, actions, null, null, null);
+            var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, JobId, jobName, jobName, new StringToken(null, null, null, "ubuntu"), sidecarContainers, null, variables, new List<MaskHint>(), resources, context, null, actions, null, null, null, null);
             return jobRequest;
         }
 

src/runnerversion

@@ -1 +1 @@
-2.165.2
+2.168.0