Make SolutionState hold onto SolutionInfo.SolutionAttributes

It was holding onto a SolutionInfo directly and then throwing away
the non-SolutionAttributes portion of it, only because when the code
was originally written SolutionInfo.SolutionAttributes didn't exist.
It's silly now.

src/Workspaces/Core/Portable/Workspace/Solution/Solution.cs

@@ -32,8 +32,8 @@ private Solution(SolutionState state)
             _state = state;
         }
 
-        internal Solution(Workspace workspace, SolutionInfo info)
-            : this(new SolutionState(workspace, info))
+        internal Solution(Workspace workspace, SolutionInfo.SolutionAttributes solutionAttributes)
+            : this(new SolutionState(workspace, solutionAttributes))
         {
         }
 

src/Workspaces/Core/Portable/Workspace/Solution/SolutionInfo.cs

@@ -112,6 +112,11 @@ public SolutionAttributes(SolutionId id, VersionStamp version, string filePath)
                 FilePath = filePath;
             }
 
+            public SolutionAttributes WithVersion(VersionStamp versionStamp)
+            {
+                return new SolutionAttributes(Id, versionStamp, FilePath);
+            }
+
             bool IObjectWritable.ShouldReuseInSerialization => true;
 
             public void WriteTo(ObjectWriter writer)

src/Workspaces/Core/Portable/Workspace/Solution/SolutionState.cs

@@ -32,7 +32,7 @@ internal partial class SolutionState
         // the version of the workspace this solution is from
         private readonly int _workspaceVersion;
 
-        private readonly SolutionInfo _solutionInfo;
+        private readonly SolutionInfo.SolutionAttributes _solutionAttributes;
         private readonly SolutionServices _solutionServices;
         private readonly IReadOnlyList<ProjectId> _projectIds;
         private readonly ImmutableDictionary<ProjectId, ProjectState> _projectIdToProjectStateMap;
@@ -50,7 +50,7 @@ internal partial class SolutionState
             BranchId branchId,
             int workspaceVersion,
             SolutionServices solutionServices,
-            SolutionInfo solutionInfo,
+            SolutionInfo.SolutionAttributes solutionAttributes,
             IEnumerable<ProjectId> projectIds,
             ImmutableDictionary<ProjectId, ProjectState> idToProjectStateMap,
             ImmutableDictionary<ProjectId, CompilationTracker> projectIdToTrackerMap,
@@ -60,6 +60,7 @@ internal partial class SolutionState
         {
             _branchId = branchId;
             _workspaceVersion = workspaceVersion;
+            _solutionAttributes = solutionAttributes;
             _solutionServices = solutionServices;
             _projectIds = projectIds.ToImmutableReadOnlyListOrEmpty();
             _projectIdToProjectStateMap = idToProjectStateMap;
@@ -68,12 +69,6 @@ internal partial class SolutionState
             _dependencyGraph = dependencyGraph;
             _lazyLatestProjectVersion = lazyLatestProjectVersion;
 
-            // ownership of information on project has moved to solution state. clear out projectInfo the state is
-            // holding on. otherwise, these information will be held onto unnecesarily by solutionInfo even after
-            // the info has changed by ProjectState.
-            // we hold onto the info so that we don't need to duplicate all information info already has in the state
-            _solutionInfo = solutionInfo.WithProjects(ImmutableArray<ProjectInfo>.Empty);
-
             // when solution state is changed, we re-calcuate its checksum
             _lazyChecksums = new AsyncLazy<SolutionStateChecksums>(ComputeChecksumsAsync, cacheResult: true);
 
@@ -82,12 +77,12 @@ internal partial class SolutionState
 
         public SolutionState(
             Workspace workspace,
-            SolutionInfo info)
+            SolutionInfo.SolutionAttributes solutionAttributes)
             : this(
                 workspace.PrimaryBranchId,
                 workspaceVersion: 0,
                 solutionServices: new SolutionServices(workspace),
-                solutionInfo: info,
+                solutionAttributes: solutionAttributes,
                 projectIds: null,
                 idToProjectStateMap: ImmutableDictionary<ProjectId, ProjectState>.Empty,
                 projectIdToTrackerMap: ImmutableDictionary<ProjectId, CompilationTracker>.Empty,
@@ -123,7 +118,7 @@ private VersionStamp ComputeLatestProjectVersion()
             return latestVersion;
         }
 
-        public SolutionInfo SolutionInfo => _solutionInfo;
+        public SolutionInfo.SolutionAttributes SolutionAttributes => _solutionAttributes;
 
         public ImmutableDictionary<ProjectId, ProjectState> ProjectStates => _projectIdToProjectStateMap;
 
@@ -152,17 +147,17 @@ private VersionStamp ComputeLatestProjectVersion()
         /// <summary>
         /// The Id of the solution. Multiple solution instances may share the same Id.
         /// </summary>
-        public SolutionId Id => _solutionInfo.Id;
+        public SolutionId Id => _solutionAttributes.Id;
 
         /// <summary>
         /// The path to the solution file or null if there is no solution file.
         /// </summary>
-        public string FilePath => _solutionInfo.FilePath;
+        public string FilePath => _solutionAttributes.FilePath;
 
         /// <summary>
         /// The solution version. This equates to the solution file's version.
         /// </summary>
-        public VersionStamp Version => _solutionInfo.Version;
+        public VersionStamp Version => _solutionAttributes.Version;
 
         /// <summary>
         /// A list of all the ids for all the projects contained by the solution.
@@ -179,7 +174,7 @@ private void CheckInvariants()
         }
 
         private SolutionState Branch(
-            SolutionInfo solutionInfo = null,
+            SolutionInfo.SolutionAttributes solutionAttributes = null,
             IEnumerable<ProjectId> projectIds = null,
             ImmutableDictionary<ProjectId, ProjectState> idToProjectStateMap = null,
             ImmutableDictionary<ProjectId, CompilationTracker> projectIdToTrackerMap = null,
@@ -189,7 +184,7 @@ private void CheckInvariants()
         {
             var branchId = GetBranchId();
 
-            solutionInfo = solutionInfo ?? _solutionInfo;
+            solutionAttributes = solutionAttributes ?? _solutionAttributes;
             projectIds = projectIds ?? _projectIds;
             idToProjectStateMap = idToProjectStateMap ?? _projectIdToProjectStateMap;
             projectIdToTrackerMap = projectIdToTrackerMap ?? _projectIdToTrackerMap;
@@ -198,7 +193,7 @@ private void CheckInvariants()
             lazyLatestProjectVersion = lazyLatestProjectVersion ?? _lazyLatestProjectVersion;
 
             if (branchId == _branchId &&
-                solutionInfo == _solutionInfo &&
+                solutionAttributes == _solutionAttributes &&
                 projectIds == _projectIds &&
                 idToProjectStateMap == _projectIdToProjectStateMap &&
                 projectIdToTrackerMap == _projectIdToTrackerMap &&
@@ -214,7 +209,7 @@ private void CheckInvariants()
                 branchId,
                 _workspaceVersion,
                 _solutionServices,
-                solutionInfo,
+                solutionAttributes,
                 projectIds,
                 idToProjectStateMap,
                 projectIdToTrackerMap,
@@ -239,7 +234,7 @@ private void CheckInvariants()
                 branchId,
                 workspaceVersion,
                 services,
-                _solutionInfo,
+                _solutionAttributes,
                 _projectIds,
                 _projectIdToProjectStateMap,
                 _projectIdToTrackerMap,
@@ -414,7 +409,7 @@ private CompilationTracker GetCompilationTracker(ProjectId projectId)
         private SolutionState AddProject(ProjectId projectId, ProjectState projectState)
         {
             // changed project list so, increment version.
-            var newSolutionInfo = _solutionInfo.WithVersion(this.Version.GetNewerVersion());
+            var newSolutionAttributes = _solutionAttributes.WithVersion(this.Version.GetNewerVersion());
 
             var newProjectIds = _projectIds.ToImmutableArray().Add(projectId);
             var newStateMap = _projectIdToProjectStateMap.Add(projectId, projectState);
@@ -441,7 +436,7 @@ private SolutionState AddProject(ProjectId projectId, ProjectState projectState)
             var newLinkedFilesMap = CreateLinkedFilesMapWithAddedProject(newStateMap[projectId]);
 
             return this.Branch(
-                solutionInfo: newSolutionInfo,
+                solutionAttributes: newSolutionAttributes,
                 projectIds: newProjectIds,
                 idToProjectStateMap: newStateMap,
                 projectIdToTrackerMap: newTrackerMap,
@@ -526,7 +521,7 @@ public SolutionState RemoveProject(ProjectId projectId)
             CheckContainsProject(projectId);
 
             // changed project list so, increment version.
-            var newSolutionInfo = _solutionInfo.WithVersion(this.Version.GetNewerVersion());
+            var newSolutionAttributes = _solutionAttributes.WithVersion(this.Version.GetNewerVersion());
 
             var newProjectIds = _projectIds.ToImmutableArray().Remove(projectId);
             var newStateMap = _projectIdToProjectStateMap.Remove(projectId);
@@ -535,7 +530,7 @@ public SolutionState RemoveProject(ProjectId projectId)
             var newLinkedFilesMap = CreateLinkedFilesMapWithRemovedProject(_projectIdToProjectStateMap[projectId]);
 
             return this.Branch(
-                solutionInfo: newSolutionInfo,
+                solutionAttributes: newSolutionAttributes,
                 projectIds: newProjectIds,
                 idToProjectStateMap: newStateMap,
                 projectIdToTrackerMap: newTrackerMap.Remove(projectId),

src/Workspaces/Core/Portable/Workspace/Solution/SolutionState_Checksum.cs

@@ -39,7 +39,7 @@ private async Task<SolutionStateChecksums> ComputeChecksumsAsync(CancellationTok
                                                             .Select(s => s.GetChecksumAsync(cancellationToken));
 
                 var serializer = _solutionServices.Workspace.Services.GetService<ISerializerService>();
-                var infoChecksum = serializer.CreateChecksum(SolutionInfo.Attributes, cancellationToken);
+                var infoChecksum = serializer.CreateChecksum(SolutionAttributes, cancellationToken);
 
                 var projectChecksums = await Task.WhenAll(projectChecksumTasks).ConfigureAwait(false);
                 return new SolutionStateChecksums(infoChecksum, new ProjectChecksumCollection(projectChecksums));

src/Workspaces/Core/Portable/Workspace/Solution/StateChecksums.cs

@@ -42,7 +42,7 @@ public SolutionStateChecksums(params object[] children) : base(WellKnownSynchron
 
             if (searchingChecksumsLeft.Remove(Info))
             {
-                result[Info] = state.SolutionInfo.Attributes;
+                result[Info] = state.SolutionAttributes;
             }
 
             if (searchingChecksumsLeft.Remove(Projects.Checksum))

src/Workspaces/Core/Portable/Workspace/Workspace.cs

@@ -135,7 +135,7 @@ internal void SetTestLogger(Action<string> writeLineMessageLogger)
         /// </summary>
         protected internal Solution CreateSolution(SolutionInfo solutionInfo)
         {
-            return new Solution(this, solutionInfo);
+            return new Solution(this, solutionInfo.Attributes);
         }
 
         /// <summary>