Make the assembly code action into pure data.

src/Features/Core/Portable/AddImport/CodeActions/AssemblyReference.AssemblyReferenceCodeAction.cs

-// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using System.Collections.Immutable;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.CodeActions;
-using Microsoft.CodeAnalysis.Host;
-using Microsoft.CodeAnalysis.Tags;
-using Microsoft.CodeAnalysis.Text;
-using Roslyn.Utilities;
-
-namespace Microsoft.CodeAnalysis.CodeFixes.AddImport
-{
-    internal abstract partial class AbstractAddImportCodeFixProvider<TSimpleNameSyntax>
-    {
-        private partial class AssemblyReference
-        {
-            private class AssemblyReferenceCodeAction : CodeAction
-            {
-                private readonly AssemblyReference _reference;
-                private readonly string _title;
-                private readonly Document _document;
-                private readonly ImmutableArray<TextChange> _textChanges;
-
-                public override string Title => _title;
-
-                public override ImmutableArray<string> Tags => WellKnownTagArrays.AddReference;
-
-                private readonly Lazy<string> _lazyResolvedPath;
-
-                public AssemblyReferenceCodeAction(
-                    AssemblyReference reference,
-                    Document document,
-                    ImmutableArray<TextChange> textChanges)
-                {
-                    _reference = reference;
-                    _document = document;
-                    _textChanges = textChanges;
-
-                    _title = $"{reference.provider.GetDescription(reference.SearchResult.NameParts)} ({string.Format(FeaturesResources.from_0, reference._referenceAssemblyWithType.AssemblyName)})";
-                    _lazyResolvedPath = new Lazy<string>(ResolvePath);
-                }
-
-                // Adding a reference is always low priority.
-                internal override CodeActionPriority Priority => CodeActionPriority.Low;
-
-                private string ResolvePath()
-                {
-                    var assemblyResolverService = _document.Project.Solution.Workspace.Services.GetService<IFrameworkAssemblyPathResolver>();
-
-                    var packageWithType = _reference._referenceAssemblyWithType;
-                    var fullyQualifiedName = string.Join(".", packageWithType.ContainingNamespaceNames.Concat(packageWithType.TypeName));
-                    var assemblyPath = assemblyResolverService?.ResolveAssemblyPath(
-                        _document.Project.Id, packageWithType.AssemblyName, fullyQualifiedName);
-
-                    return assemblyPath;
-                }
-
-                internal override bool PerformFinalApplicabilityCheck => true;
-
-                internal override bool IsApplicable(Workspace workspace)
-                {
-                    return !string.IsNullOrWhiteSpace(_lazyResolvedPath.Value);
-                }
-
-                protected override async Task<IEnumerable<CodeActionOperation>> ComputeOperationsAsync(CancellationToken cancellationToken)
-                {
-                    var service = _document.Project.Solution.Workspace.Services.GetService<IMetadataService>();
-                    var resolvedPath = _lazyResolvedPath.Value;
-                    var reference = service.GetReference(resolvedPath, MetadataReferenceProperties.Assembly);
-
-                    var oldText = await _document.GetTextAsync(cancellationToken).ConfigureAwait(false);
-                    var newText = oldText.WithChanges(_textChanges);
-
-                    var newDocument = _document.WithText(newText);
-
-                    // Now add the actual assembly reference.
-                    var newProject = newDocument.Project;
-                    newProject = newProject.WithMetadataReferences(
-                        newProject.MetadataReferences.Concat(reference));
-
-                    var operation = new ApplyChangesOperation(newProject.Solution);
-                    return SpecializedCollections.SingletonEnumerable<CodeActionOperation>(operation);
-                }
-            }
-        }
-    }
-}
\ No newline at end of file

src/Features/Core/Portable/AddImport/CodeActions/AssemblyReferenceCodeAction.cs

+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CodeActions;
+using Microsoft.CodeAnalysis.Host;
+using Microsoft.CodeAnalysis.SymbolSearch;
+using Microsoft.CodeAnalysis.Tags;
+using Microsoft.CodeAnalysis.Text;
+using Roslyn.Utilities;
+
+namespace Microsoft.CodeAnalysis.CodeFixes.AddImport
+{
+    internal abstract partial class AbstractAddImportCodeFixProvider<TSimpleNameSyntax>
+    {
+        private class AssemblyReferenceCodeAction : CodeAction
+        {
+            private readonly ReferenceAssemblyWithTypeResult _referenceAssemblyWithType;
+            private readonly string _title;
+            private readonly Document _document;
+            private readonly ImmutableArray<TextChange> _textChanges;
+
+            public override string Title => _title;
+
+            public override ImmutableArray<string> Tags => WellKnownTagArrays.AddReference;
+
+            private readonly Lazy<string> _lazyResolvedPath;
+
+            public AssemblyReferenceCodeAction(
+                string title,
+                ReferenceAssemblyWithTypeResult referenceAssemblyWithType,
+                Document document,
+                ImmutableArray<TextChange> textChanges)
+            {
+                _referenceAssemblyWithType = referenceAssemblyWithType;
+                _document = document;
+                _textChanges = textChanges;
+
+                _title = title;
+                _lazyResolvedPath = new Lazy<string>(ResolvePath);
+            }
+
+            // Adding a reference is always low priority.
+            internal override CodeActionPriority Priority => CodeActionPriority.Low;
+
+            private string ResolvePath()
+            {
+                var assemblyResolverService = _document.Project.Solution.Workspace.Services.GetService<IFrameworkAssemblyPathResolver>();
+
+                var fullyQualifiedName = string.Join(
+                    ".", _referenceAssemblyWithType.ContainingNamespaceNames.Concat(_referenceAssemblyWithType.TypeName));
+
+                var assemblyPath = assemblyResolverService?.ResolveAssemblyPath(
+                    _document.Project.Id, _referenceAssemblyWithType.AssemblyName, fullyQualifiedName);
+
+                return assemblyPath;
+            }
+
+            internal override bool PerformFinalApplicabilityCheck
+                => true;
+
+            internal override bool IsApplicable(Workspace workspace)
+                => !string.IsNullOrWhiteSpace(_lazyResolvedPath.Value);
+
+            protected override async Task<IEnumerable<CodeActionOperation>> ComputeOperationsAsync(CancellationToken cancellationToken)
+            {
+                var service = _document.Project.Solution.Workspace.Services.GetService<IMetadataService>();
+                var resolvedPath = _lazyResolvedPath.Value;
+                var reference = service.GetReference(resolvedPath, MetadataReferenceProperties.Assembly);
+
+                var oldText = await _document.GetTextAsync(cancellationToken).ConfigureAwait(false);
+                var newText = oldText.WithChanges(_textChanges);
+
+                var newDocument = _document.WithText(newText);
+
+                // Now add the actual assembly reference.
+                var newProject = newDocument.Project;
+                newProject = newProject.WithMetadataReferences(
+                    newProject.MetadataReferences.Concat(reference));
+
+                var operation = new ApplyChangesOperation(newProject.Solution);
+                return SpecializedCollections.SingletonEnumerable<CodeActionOperation>(operation);
+            }
+        }
+    }
+}
\ No newline at end of file

src/Features/Core/Portable/AddImport/References/AssemblyReference.cs

@@ -29,7 +29,9 @@ private partial class AssemblyReference : Reference
                 var textChanges = await GetTextChangesAsync(
                     document, node, placeSystemNamespaceFirst, cancellationToken).ConfigureAwait(false);
 
-                return new AssemblyReferenceCodeAction(this, document, textChanges);
+                var title = $"{this.provider.GetDescription(this.SearchResult.NameParts)} ({string.Format(FeaturesResources.from_0, _referenceAssemblyWithType.AssemblyName)})";
+
+                return new AssemblyReferenceCodeAction(title, _referenceAssemblyWithType, document, textChanges);
             }
 
             public override bool Equals(object obj)

src/Features/Core/Portable/Features.csproj

@@ -99,7 +99,7 @@
     <Compile Include="..\..\..\Compilers\Shared\DesktopShim.cs">
       <Link>Shared\Utilities\DesktopShim.cs</Link>
     </Compile>
-    <Compile Include="AddImport\CodeActions\AssemblyReference.AssemblyReferenceCodeAction.cs" />
+    <Compile Include="AddImport\CodeActions\AssemblyReferenceCodeAction.cs" />
     <Compile Include="AddImport\SearchScopes\AllSymbolsProjectSearchScope.cs" />
     <Compile Include="AddImport\SearchScopes\MetadataSymbolsSearchScope.cs" />
     <Compile Include="AddImport\SearchScopes\ProjectSearchScope.cs" />