Add question flag to "question" the build if it is incremental

eng/BootStrapMSBuild.targets

@@ -119,63 +119,82 @@
 
     <!-- Copy in props and targets from the machine-installed MSBuildExtensionsPath -->
     <Copy SourceFiles="@(InstalledVersionedExtensions)"
-          DestinationFiles="@(InstalledVersionedExtensions->'$(BootstrapDestination)$(TargetMSBuildToolsVersion)\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(InstalledVersionedExtensions->'$(BootstrapDestination)$(TargetMSBuildToolsVersion)\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
     <Copy SourceFiles="@(SdkResolverFiles)"
-          DestinationFiles="@(SdkResolverFiles->'$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\SdkResolvers\Microsoft.DotNet.MSBuildSdkResolver\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(SdkResolverFiles->'$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\SdkResolvers\Microsoft.DotNet.MSBuildSdkResolver\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
 
     <Copy SourceFiles="@(InstalledMicrosoftExtensions)"
-          DestinationFiles="@(InstalledMicrosoftExtensions->'$(BootstrapDestination)Microsoft\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(InstalledMicrosoftExtensions->'$(BootstrapDestination)Microsoft\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
 
     <Copy SourceFiles="@(InstalledSdks)"
           DestinationFiles="@(InstalledSdks -> '$(BootstrapDestination)Sdks\%(RecursiveDir)%(Filename)%(Extension)')"
-          Condition="'$(MonoBuild)' != 'true'" />
+          Condition="'$(MonoBuild)' != 'true'"
+          SkipUnchangedFiles="true" />
     <Copy SourceFiles="@(InstalledSdks)"
           DestinationFiles="@(InstalledSdks -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\Sdks\%(RecursiveDir)%(Filename)%(Extension)')"
-          Condition="'$(MonoBuild)' == 'true'" />
+          Condition="'$(MonoBuild)' == 'true'"
+          SkipUnchangedFiles="true" />
 
     <Copy SourceFiles="@(InstalledStaticAnalysisTools)"
-          DestinationFiles="@(InstalledStaticAnalysisTools -> '$(BootstrapDestination)..\Team Tools\Static Analysis Tools\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(InstalledStaticAnalysisTools -> '$(BootstrapDestination)..\Team Tools\Static Analysis Tools\%(RecursiveDir)%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
 
     <Copy SourceFiles="@(InstalledNuGetFiles)"
-          DestinationFiles="@(InstalledNuGetFiles->'$(BootstrapDestination)Microsoft\NuGet\%(Filename)%(Extension)')" />
+          DestinationFiles="@(InstalledNuGetFiles->'$(BootstrapDestination)Microsoft\NuGet\%(Filename)%(Extension)')"
+          SkipUnchangedFiles="true" />
 
     <Copy Condition="'$(MonoBuild)' != 'true'"
           SourceFiles="@(_NuGetRuntimeDependencies)"
-          DestinationFolder="$(BootstrapDestination)..\Common7\IDE\CommonExtensions\Microsoft\NuGet\" />
+          DestinationFolder="$(BootstrapDestination)..\Common7\IDE\CommonExtensions\Microsoft\NuGet\"
+          SkipUnchangedFiles="true" />
     <Copy Condition="'$(MonoBuild)' == 'true'"
           SourceFiles="@(_NuGetRuntimeDependencies)"
-          DestinationFolder="$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin" />
+          DestinationFolder="$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin" 
+          SkipUnchangedFiles="true" />
 
     <Copy SourceFiles="@(NuGetSdkResolverManifest)"
-          DestinationFolder="$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\SdkResolvers\Microsoft.Build.NuGetSdkResolver" />
+          DestinationFolder="$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\SdkResolvers\Microsoft.Build.NuGetSdkResolver" 
+          SkipUnchangedFiles="true" />
 
     <!-- Delete shim projects, because they point where we can't follow. -->
     <!-- It would be better to just not copy these. -->
     <Delete Files="@(ShimTargets->'$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\%(FileName)%(Extension)')" />
 
     <!-- Copy our binaries -->
     <Copy SourceFiles="@(FreshlyBuiltBinaries)"
-          DestinationFiles="@(FreshlyBuiltBinaries -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(FreshlyBuiltBinaries -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
+
     <Copy SourceFiles="@(RoslynBinaries)"
-          DestinationFiles="@(RoslynBinaries -> '$(BootstrapDestination)15.0\Bin\Roslyn\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(RoslynBinaries -> '$(BootstrapDestination)15.0\Bin\Roslyn\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
 
     <!-- Copy our binaries to the x64 location. -->
-     <Copy SourceFiles="@(FreshlyBuiltBinariesx64)"
-          DestinationFiles="@(FreshlyBuiltBinariesx64 -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\amd64\%(RecursiveDir)%(Filename)%(Extension)')" />
+    <Copy SourceFiles="@(FreshlyBuiltBinariesx64)"
+          DestinationFiles="@(FreshlyBuiltBinariesx64 -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\amd64\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
 
     <!-- Copy our binaries to the arm64 location. -->
-     <Copy SourceFiles="@(FreshlyBuiltBinariesArm64)"
-          DestinationFiles="@(FreshlyBuiltBinariesArm64 -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\arm64\%(RecursiveDir)%(Filename)%(Extension)')" />
+    <Copy SourceFiles="@(FreshlyBuiltBinariesArm64)"
+          DestinationFiles="@(FreshlyBuiltBinariesArm64 -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\arm64\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
 
     <!-- Copy our freshly-built props and targets, overwriting anything we copied from the machine -->
     <Copy SourceFiles="@(FreshlyBuiltRootProjects)"
-          DestinationFiles="@(FreshlyBuiltRootProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\%(Filename)%(Extension)')" />
+          DestinationFiles="@(FreshlyBuiltRootProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
     <Copy SourceFiles="@(FreshlyBuiltProjects)"
-          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
     <Copy SourceFiles="@(FreshlyBuiltProjects)"
-          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\amd64\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\amd64\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
     <Copy SourceFiles="@(FreshlyBuiltProjects)"
-          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\arm64\%(RecursiveDir)%(Filename)%(Extension)')" />
+          DestinationFiles="@(FreshlyBuiltProjects -> '$(BootstrapDestination)$(TargetMSBuildToolsVersion)\Bin\arm64\%(RecursiveDir)%(Filename)%(Extension)')" 
+          SkipUnchangedFiles="true" />
 
   </Target>
 

src/Build.UnitTests/BackEnd/TargetBuilder_Tests.cs

@@ -237,6 +237,41 @@ Skipping target ""Build"" because all output files are up-to-date with respect t
             }
         }
 
+        [Fact]
+        public void TestErrorForSkippedTargetInputsAndOutputs()
+        {
+            string projectContents = @"
+<Project>
+  <Target Name=""Build"" Inputs=""a.txt;b.txt"" Outputs=""c.txt"">
+    <Message Text=""test"" Importance=""High"" />
+  </Target>
+</Project>";
+
+            using (var env = TestEnvironment.Create())
+            {
+                var buildParameters = new BuildParameters()
+                {
+                    Question = true,
+                };
+
+                using (var buildSession = new Helpers.BuildManagerSession(env, buildParameters))
+                {
+                    var files = env.CreateTestProjectWithFiles(projectContents, new[] { "a.txt", "b.txt", "c.txt" });
+                    var fileA = new FileInfo(files.CreatedFiles[0]);
+                    var fileB = new FileInfo(files.CreatedFiles[1]);
+                    var fileC = new FileInfo(files.CreatedFiles[2]);
+
+                    var now = DateTime.UtcNow;
+                    fileA.LastWriteTimeUtc = now - TimeSpan.FromSeconds(10);
+                    fileB.LastWriteTimeUtc = now + TimeSpan.FromSeconds(10);
+                    fileC.LastWriteTimeUtc = now;
+
+                    var result = buildSession.BuildProjectFile(files.ProjectFile);
+                    result.OverallResult.ShouldBe(BuildResultCode.Failure);
+                }
+            }
+        }
+
         /// <summary>
         /// Ensure that skipped targets only infer outputs once
         /// </summary>

src/Build.UnitTests/BackEnd/TargetUpToDateChecker_Tests.cs

@@ -576,7 +576,7 @@ out ItemDictionary<ProjectItemInstance> upToDateTargetInputs
                 ItemBucket itemBucket = new ItemBucket(null, null, new Lookup(itemsByName, new PropertyDictionary<ProjectPropertyInstance>()), 0);
                 TargetUpToDateChecker analyzer = new TargetUpToDateChecker(p, p.Targets["Build"], _mockHost, BuildEventContext.Invalid);
 
-                return analyzer.PerformDependencyAnalysis(itemBucket, out changedTargetInputs, out upToDateTargetInputs);
+                return analyzer.PerformDependencyAnalysis(itemBucket, false, out changedTargetInputs, out upToDateTargetInputs);
             }
             finally
             {

src/Build.UnitTests/BackEnd/TaskBuilder_Tests.cs

@@ -138,7 +138,6 @@ public void CanceledTasksDoNotLogMSB4181()
                     Loggers = new ILogger[] { logger },
                     EnableNodeReuse = false
                 };
-                ;
 
                 BuildRequestData data = new BuildRequestData(project.CreateProjectInstance(), new string[] { "test" }, collection.HostServices);
                 manager.BeginBuild(_parameters);

src/Build/BackEnd/BuildManager/BuildParameters.cs

@@ -205,6 +205,8 @@ public class BuildParameters : ITranslatable
         /// </summary>
         private bool _logInitialPropertiesAndItems;
 
+        private bool _question;
+
         /// <summary>
         /// The settings used to load the project under build
         /// </summary>
@@ -303,6 +305,7 @@ internal BuildParameters(BuildParameters other, bool resetEnvironment = false)
             _outputResultsCacheFile = other._outputResultsCacheFile;
             DiscardBuildResults = other.DiscardBuildResults;
             LowPriority = other.LowPriority;
+            Question = other.Question;
             ProjectCacheDescriptor = other.ProjectCacheDescriptor;
         }
 
@@ -790,6 +793,15 @@ public string OutputResultsCacheFile
         /// </summary>
         public bool LowPriority { get; set; }
 
+        /// <summary>
+        /// Gets or sets a value that will error when the build process fails an incremental check.
+        /// </summary>
+        public bool Question
+        {
+            get => _question;
+            set => _question = value;
+        } 
+
         /// <summary>
         /// Gets or sets the project cache description to use for all <see cref="BuildSubmission"/> or <see cref="GraphBuildSubmission"/>
         /// in addition to any potential project caches described in each project.
@@ -854,6 +866,7 @@ void ITranslatable.Translate(ITranslator translator)
             translator.TranslateEnum(ref _projectLoadSettings, (int) _projectLoadSettings);
             translator.Translate(ref _interactive);
             translator.Translate(ref _isolateProjects);
+            translator.Translate(ref _question);
 
             // ProjectRootElementCache is not transmitted.
             // ResetCaches is not transmitted.

src/Build/BackEnd/Components/RequestBuilder/TargetEntry.cs

@@ -463,7 +463,7 @@ internal async Task ExecuteTarget(ITaskBuilder taskBuilder, BuildRequestEntry re
                         // UNDONE: (Refactor) Refactor TargetUpToDateChecker to take a logging context, not a logging service.
                         MSBuildEventSource.Log.TargetUpToDateStart();
                         TargetUpToDateChecker dependencyAnalyzer = new TargetUpToDateChecker(requestEntry.RequestConfiguration.Project, _target, targetLoggingContext.LoggingService, targetLoggingContext.BuildEventContext);
-                        DependencyAnalysisResult dependencyResult = dependencyAnalyzer.PerformDependencyAnalysis(bucket, out changedTargetInputs, out upToDateTargetInputs);
+                        DependencyAnalysisResult dependencyResult = dependencyAnalyzer.PerformDependencyAnalysis(bucket, _host.BuildParameters.Question, out changedTargetInputs, out upToDateTargetInputs);
                         MSBuildEventSource.Log.TargetUpToDateStop((int)dependencyResult);
 
                         switch (dependencyResult)
@@ -472,6 +472,13 @@ internal async Task ExecuteTarget(ITaskBuilder taskBuilder, BuildRequestEntry re
                             case DependencyAnalysisResult.FullBuild:
                             case DependencyAnalysisResult.IncrementalBuild:
                             case DependencyAnalysisResult.SkipUpToDate:
+                                if (dependencyResult != DependencyAnalysisResult.SkipUpToDate && _host.BuildParameters.Question && !string.IsNullOrEmpty(_target.Inputs) && !string.IsNullOrEmpty(_target.Outputs))
+                                {
+                                    targetSuccess = false;
+                                    aggregateResult = aggregateResult.AggregateResult(new WorkUnitResult(WorkUnitResultCode.Canceled, WorkUnitActionCode.Stop, null));
+                                    break;
+                                }
+
                                 // Create the lookups used to hold the current set of properties and items
                                 lookupForInference = bucket.Lookup;
                                 lookupForExecution = bucket.Lookup.Clone();

src/Build/BackEnd/Components/RequestBuilder/TargetUpToDateChecker.cs

@@ -119,6 +119,7 @@ private string TargetOutputSpecification
         /// incremental build is needed.
         /// </remarks>
         /// <param name="bucket"></param>
+        /// <param name="question"></param>
         /// <param name="changedTargetInputs"></param>
         /// <param name="upToDateTargetInputs"></param>
         /// <returns>
@@ -131,6 +132,7 @@ private string TargetOutputSpecification
         internal DependencyAnalysisResult PerformDependencyAnalysis
         (
             ItemBucket bucket,
+            bool question,
             out ItemDictionary<ProjectItemInstance> changedTargetInputs,
             out ItemDictionary<ProjectItemInstance> upToDateTargetInputs
         )
@@ -255,7 +257,7 @@ out ItemDictionary<ProjectItemInstance> upToDateTargetInputs
                 }
             }
 
-            LogReasonForBuildingTarget(result);
+            LogReasonForBuildingTarget(result, question);
 
             return result;
         }
@@ -264,15 +266,23 @@ out ItemDictionary<ProjectItemInstance> upToDateTargetInputs
         /// Does appropriate logging to indicate why this target is being built fully or partially.
         /// </summary>
         /// <param name="result"></param>
-        private void LogReasonForBuildingTarget(DependencyAnalysisResult result)
+        /// <param name="question"></param>
+        private void LogReasonForBuildingTarget(DependencyAnalysisResult result, bool question)
         {
             // Only if we are not logging just critical events should we be logging the details
             if (!_loggingService.OnlyLogCriticalEvents)
             {
                 if (result == DependencyAnalysisResult.FullBuild && _dependencyAnalysisDetail.Count > 0)
                 {
-                    // For the full build decision the are three possible outcomes
-                    _loggingService.LogComment(_buildEventContext, MessageImportance.Low, "BuildTargetCompletely", _targetToAnalyze.Name);
+                    if (question)
+                    {
+                        _loggingService.LogError(_buildEventContext, new BuildEventFileInfo(String.Empty), "BuildTargetCompletely", _targetToAnalyze.Name);
+                    }
+                    else
+                    {
+                        // For the full build decision, there are three possible outcomes
+                        _loggingService.LogComment(_buildEventContext, MessageImportance.Low, "BuildTargetCompletely", _targetToAnalyze.Name);
+                    }
 
                     foreach (DependencyAnalysisLogDetail logDetail in _dependencyAnalysisDetail)
                     {
@@ -282,8 +292,15 @@ private void LogReasonForBuildingTarget(DependencyAnalysisResult result)
                 }
                 else if (result == DependencyAnalysisResult.IncrementalBuild)
                 {
-                    // For the partial build decision the are three possible outcomes
-                    _loggingService.LogComment(_buildEventContext, MessageImportance.Normal, "BuildTargetPartially", _targetToAnalyze.Name);
+                    if (question)
+                    {
+                        _loggingService.LogError(_buildEventContext, new BuildEventFileInfo(String.Empty), "BuildTargetPartially", _targetToAnalyze.Name);
+                    }
+                    else
+                    {
+                        // For the partial build decision the are three possible outcomes
+                        _loggingService.LogComment(_buildEventContext, MessageImportance.Normal, "BuildTargetPartially", _targetToAnalyze.Name);
+                    }
                     foreach (DependencyAnalysisLogDetail logDetail in _dependencyAnalysisDetail)
                     {
                         string reason = GetIncrementalBuildReason(logDetail);

src/Build/BackEnd/TaskExecutionHost/TaskExecutionHost.cs

@@ -368,6 +368,11 @@ bool ITaskExecutionHost.SetTaskParameters(IDictionary<string, (string, ElementLo
                 }
             }
 
+            if (this.TaskInstance is IIncrementalTask incrementalTask)
+            {
+                incrementalTask.SetQuestion(_buildComponentHost.BuildParameters.Question);
+            }
+
             if (taskInitialized)
             {
                 // See if any required properties were not set

src/Directory.Build.targets

@@ -137,7 +137,7 @@
     </ItemGroup>
   </Target>
 
-  <Target Name="CreateTypeLib" BeforeTargets="AfterBuild" Condition="'$(BuildingInsideVisualStudio)' != 'true' and '$(CreateTlb)' == 'true' and $([MSBuild]::IsOSPlatform('windows')) and '$(TargetFrameworkIdentifier)' == '.NETFramework' and '$(MSBuildRuntimeType)' != 'Core'">
+  <Target Name="CreateTypeLib" BeforeTargets="AfterBuild" Inputs="$(TargetPath)" Outputs="$(TargetDir)$(TargetName).tlb;$(TargetDir)x64\$(TargetName).tlb" Condition="'$(BuildingInsideVisualStudio)' != 'true' and '$(CreateTlb)' == 'true' and $([MSBuild]::IsOSPlatform('windows')) and '$(TargetFrameworkIdentifier)' == '.NETFramework' and '$(MSBuildRuntimeType)' != 'Core'">
     <PropertyGroup>
       <TlbExpPath>$([Microsoft.Build.Utilities.ToolLocationHelper]::GetPathToDotNetFrameworkSdkFile('tlbexp.exe'))</TlbExpPath>
       <!-- Provide a mechanism for turning on verbose TlbExp output for diagnosing issues -->

src/Framework/IIncrementalTask.cs

@@ -0,0 +1,15 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+#nullable disable
+
+namespace Microsoft.Build.Framework
+{
+    /// <summary>
+    /// Interface for tasks which is incremental
+    /// </summary>
+    public interface IIncrementalTask
+    {
+        void  SetQuestion(bool question);
+    }
+}