Optionally output unresolved assembly conflicts (#5990)

Allow users to specify in OutputUnresolvedAssemblyConflicts (an optional parameter to RAR) that they want assembly conflicts provided in an output item and, if true, creates it.

Fixes #5934

ref/Microsoft.Build.Tasks.Core/net/Microsoft.Build.Tasks.Core.cs

@@ -926,6 +926,7 @@ public ResolveAssemblyReference() { }
         public Microsoft.Build.Framework.ITaskItem[] InstalledAssemblySubsetTables { get { throw null; } set { } }
         public Microsoft.Build.Framework.ITaskItem[] InstalledAssemblyTables { get { throw null; } set { } }
         public string[] LatestTargetFrameworkDirectories { get { throw null; } set { } }
+        public bool OutputUnresolvedAssemblyConflicts { get { throw null; } set { } }
         public string ProfileName { get { throw null; } set { } }
         [Microsoft.Build.Framework.OutputAttribute]
         public Microsoft.Build.Framework.ITaskItem[] RelatedFiles { get { throw null; } }
@@ -954,6 +955,8 @@ public ResolveAssemblyReference() { }
         public string[] TargetFrameworkSubsets { get { throw null; } set { } }
         public string TargetFrameworkVersion { get { throw null; } set { } }
         public string TargetProcessorArchitecture { get { throw null; } set { } }
+        [Microsoft.Build.Framework.OutputAttribute]
+        public Microsoft.Build.Framework.ITaskItem[] UnresolvedAssemblyConflicts { get { throw null; } }
         public bool UnresolveFrameworkAssembliesFromHigherFrameworks { get { throw null; } set { } }
         public string WarnOrErrorOnTargetArchitectureMismatch { get { throw null; } set { } }
         public override bool Execute() { throw null; }

ref/Microsoft.Build.Tasks.Core/netstandard/Microsoft.Build.Tasks.Core.cs

@@ -671,6 +671,7 @@ public ResolveAssemblyReference() { }
         public Microsoft.Build.Framework.ITaskItem[] InstalledAssemblySubsetTables { get { throw null; } set { } }
         public Microsoft.Build.Framework.ITaskItem[] InstalledAssemblyTables { get { throw null; } set { } }
         public string[] LatestTargetFrameworkDirectories { get { throw null; } set { } }
+        public bool OutputUnresolvedAssemblyConflicts { get { throw null; } set { } }
         public string ProfileName { get { throw null; } set { } }
         [Microsoft.Build.Framework.OutputAttribute]
         public Microsoft.Build.Framework.ITaskItem[] RelatedFiles { get { throw null; } }
@@ -699,6 +700,8 @@ public ResolveAssemblyReference() { }
         public string[] TargetFrameworkSubsets { get { throw null; } set { } }
         public string TargetFrameworkVersion { get { throw null; } set { } }
         public string TargetProcessorArchitecture { get { throw null; } set { } }
+        [Microsoft.Build.Framework.OutputAttribute]
+        public Microsoft.Build.Framework.ITaskItem[] UnresolvedAssemblyConflicts { get { throw null; } }
         public bool UnresolveFrameworkAssembliesFromHigherFrameworks { get { throw null; } set { } }
         public string WarnOrErrorOnTargetArchitectureMismatch { get { throw null; } set { } }
         public override bool Execute() { throw null; }

src/Tasks.UnitTests/AssemblyDependency/Miscellaneous.cs

@@ -3686,6 +3686,37 @@ public void ConflictGeneratesMessageReferencingAssemblyName()
             warningMessage.ShouldContain(ResourceUtilities.FormatResourceStringIgnoreCodeAndKeyword("ResolveAssemblyReference.FourSpaceIndent", ResourceUtilities.FormatResourceStringIgnoreCodeAndKeyword("ResolveAssemblyReference.ReferenceDependsOn", "D, Version=1.0.0.0, CulTUre=neutral, PublicKeyToken=aaaaaaaaaaaaaaaa", Path.Combine(s_myLibraries_V1Path, "D.dll"))));
         }
 
+        [Fact]
+        public void ConflictOutputsExtraInformationOnDemand()
+        {
+            ResolveAssemblyReference t = new ResolveAssemblyReference();
+
+            MockEngine e = new MockEngine(_output);
+            t.BuildEngine = e;
+
+            t.Assemblies = new ITaskItem[]
+            {
+                new TaskItem("B"),
+                new TaskItem("D, Version=1.0.0.0, Culture=neutral, PublicKeyToken=aaaaaaaaaaaaaaaa")
+            };
+
+            t.SearchPaths = new string[]
+            {
+                s_myLibrariesRootPath, s_myLibraries_V2Path, s_myLibraries_V1Path
+            };
+
+            t.TargetFrameworkDirectories = new string[] { s_myVersion20Path };
+            t.OutputUnresolvedAssemblyConflicts = true;
+
+            Execute(t);
+
+            ITaskItem[] conflicts = t.UnresolvedAssemblyConflicts;
+            conflicts.Length.ShouldBe(1);
+            conflicts[0].ItemSpec.ShouldBe("D");
+            conflicts[0].GetMetadata("victorVersionNumber").ShouldBe("1.0.0.0");
+            conflicts[0].GetMetadata("victimVersionNumber").ShouldBe("2.0.0.0");
+        }
+
         /// <summary>
         /// Consider this dependency chain:
         ///

src/Tasks/AssemblyDependency/ResolveAssemblyReference.cs

@@ -86,6 +86,7 @@ public ResolveAssemblyReference()
         private ITaskItem[] _scatterFiles = Array.Empty<TaskItem>();
         private ITaskItem[] _copyLocalFiles = Array.Empty<TaskItem>();
         private ITaskItem[] _suggestedRedirects = Array.Empty<TaskItem>();
+        private List<ITaskItem> _unresolvedConflicts = new List<ITaskItem>();
         private string[] _targetFrameworkSubsets = Array.Empty<string>();
         private string[] _fullTargetFrameworkSubsetNames = Array.Empty<string>();
         private string _targetedFrameworkMoniker = String.Empty;
@@ -214,6 +215,11 @@ public bool IgnoreTargetFrameworkAttributeVersionMismatch
         /// </remarks>
         public bool FindDependenciesOfExternallyResolvedReferences { get; set; }
 
+        /// <summary>
+        /// If true, outputs any unresolved assembly conflicts (MSB3277) in UnresolvedAssemblyConflicts.
+        /// </summary>
+        public bool OutputUnresolvedAssemblyConflicts { get; set; }
+
         /// <summary>
         /// List of target framework subset names which will be searched for in the target framework directories
         /// </summary>
@@ -915,6 +921,13 @@ public String DependsOnNETStandard
             private set;
         }
 
+        /// <summary>
+        /// If OutputUnresolvedAssemblyConflicts then a list of information about unresolved conflicts that normally would have
+        /// been outputted in MSB3277. Otherwise empty.
+        /// </summary>
+        [Output]
+        public ITaskItem[] UnresolvedAssemblyConflicts => _unresolvedConflicts.ToArray();
+
         #endregion
         #region Logging
 
@@ -990,16 +1003,30 @@ quiet at the engine level.
                             // Log the reference which lost the conflict and the dependencies and source items which caused it.
                             LogReferenceDependenciesAndSourceItemsToStringBuilder(fusionName, conflictCandidate, logDependencies.AppendLine());
 
+                            string output = StringBuilderCache.GetStringAndRelease(logConflict);
+                            string details = string.Empty;
                             if (logWarning)
                             {
                                 // This warning is logged regardless of AutoUnify since it means a conflict existed where the reference	
                                 // chosen was not the conflict victor in a version comparison. In other words, the victor was older.
-                                Log.LogWarningWithCodeFromResources("ResolveAssemblyReference.FoundConflicts", assemblyName.Name, StringBuilderCache.GetStringAndRelease(logConflict));
+                                Log.LogWarningWithCodeFromResources("ResolveAssemblyReference.FoundConflicts", assemblyName.Name, output);
                             }
                             else
                             {
-                                Log.LogMessage(ChooseReferenceLoggingImportance(conflictCandidate), StringBuilderCache.GetStringAndRelease(logConflict));
-                                Log.LogMessage(MessageImportance.Low, StringBuilderCache.GetStringAndRelease(logDependencies));
+                                details = StringBuilderCache.GetStringAndRelease(logDependencies);
+                                Log.LogMessage(ChooseReferenceLoggingImportance(conflictCandidate), output);
+                                Log.LogMessage(MessageImportance.Low, details);
+                            }
+
+                            if (OutputUnresolvedAssemblyConflicts)
+                            {
+                                _unresolvedConflicts.Add(new TaskItem(assemblyName.Name, new Dictionary<string, string>()
+                                {
+                                    { "logMessage", output },
+                                    { "logMessageDetails", details },
+                                    { "victorVersionNumber", victor.ReferenceVersion.ToString() },
+                                    { "victimVersionNumber", conflictCandidate.ReferenceVersion.ToString() }
+                                }));
                             }
                         }
                     }

src/Tasks/Microsoft.Common.CurrentVersion.targets

@@ -2156,6 +2156,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       <ResolveAssemblyReferencesFindRelatedSatellites Condition="'$(ResolveAssemblyReferencesFindRelatedSatellites)' == ''">$(BuildingProject)</ResolveAssemblyReferencesFindRelatedSatellites>
       <ResolveAssemblyReferencesFindSerializationAssemblies Condition="'$(ResolveAssemblyReferencesFindSerializationAssemblies)' == ''">$(BuildingProject)</ResolveAssemblyReferencesFindSerializationAssemblies>
       <ResolveAssemblyReferencesFindRelatedFiles Condition="'$(ResolveAssemblyReferencesFindRelatedFiles)' == ''">$(BuildingProject)</ResolveAssemblyReferencesFindRelatedFiles>
+      <ResolveAssemblyReferenceOutputUnresolvedAssemblyConflicts Condition="'$(ResolveAssemblyReferenceOutputUnresolvedAssemblyConflicts)' == ''">false</ResolveAssemblyReferenceOutputUnresolvedAssemblyConflicts>
     </PropertyGroup>
 
     <ItemGroup>
@@ -2218,6 +2219,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
         IgnoreTargetFrameworkAttributeVersionMismatch ="$(ResolveAssemblyReferenceIgnoreTargetFrameworkAttributeVersionMismatch)"
         FindDependenciesOfExternallyResolvedReferences="$(FindDependenciesOfExternallyResolvedReferences)"
         ContinueOnError="$(ContinueOnError)"
+        OutputUnresolvedAssemblyConflicts="$(ResolveAssemblyReferenceOutputUnresolvedAssemblyConflicts)"
         Condition="'@(Reference)'!='' or '@(_ResolvedProjectReferencePaths)'!='' or '@(_ExplicitReference)' != ''"
         >
 
@@ -2233,6 +2235,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       <Output TaskParameter="FilesWritten" ItemName="FileWrites"/>
       <Output TaskParameter="DependsOnSystemRuntime" PropertyName="DependsOnSystemRuntime"/>
       <Output TaskParameter="DependsOnNETStandard" PropertyName="_DependsOnNETStandard"/>
+      <Output TaskParameter="UnresolvedAssemblyConflicts" ItemName="ResolveAssemblyReferenceUnresolvedAssemblyConflicts"/>
     </ResolveAssemblyReference>
   </Target>