private async Task <ImmutableArray <CodeFix> > GetSuppressionsAsync(
            Document documentOpt, Project project, IEnumerable <Diagnostic> diagnostics, SuppressionTargetInfo suppressionTargetInfo, bool skipSuppressMessage, bool skipUnsuppress, CancellationToken cancellationToken)
        {
            // We only care about diagnostics that can be suppressed/unsuppressed.
            diagnostics = diagnostics.Where(CanBeSuppressedOrUnsuppressed);
            if (diagnostics.IsEmpty())
            {
                return(ImmutableArray <CodeFix> .Empty);
            }

            if (!skipSuppressMessage)
            {
                var compilation = await project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);

                var suppressMessageAttribute = compilation.SuppressMessageAttributeType();
                skipSuppressMessage = suppressMessageAttribute == null || !suppressMessageAttribute.IsAttribute();
            }

            var result = ArrayBuilder <CodeFix> .GetInstance();

            foreach (var diagnostic in diagnostics)
            {
                if (!diagnostic.IsSuppressed)
                {
                    var nestedActions = ArrayBuilder <NestedSuppressionCodeAction> .GetInstance();

                    if (diagnostic.Location.IsInSource && documentOpt != null)
                    {
                        // pragma warning disable.
                        nestedActions.Add(PragmaWarningCodeAction.Create(suppressionTargetInfo, documentOpt, diagnostic, this));
                    }

                    // SuppressMessageAttribute suppression is not supported for compiler diagnostics.
                    if (!skipSuppressMessage && !SuppressionHelpers.IsCompilerDiagnostic(diagnostic))
                    {
                        // global assembly-level suppress message attribute.
                        nestedActions.Add(new GlobalSuppressMessageCodeAction(suppressionTargetInfo.TargetSymbol, project, diagnostic, this));
                    }

                    if (nestedActions.Count > 0)
                    {
                        var codeAction = new TopLevelSuppressionCodeAction(
                            diagnostic, nestedActions.ToImmutableAndFree());
                        result.Add(new CodeFix(project, codeAction, diagnostic));
                    }
                }
                else if (!skipUnsuppress)
                {
                    var codeAction = await RemoveSuppressionCodeAction.CreateAsync(suppressionTargetInfo, documentOpt, project, diagnostic, this, cancellationToken).ConfigureAwait(false);

                    if (codeAction != null)
                    {
                        result.Add(new CodeFix(project, codeAction, diagnostic));
                    }
                }
            }

            return(result.ToImmutableAndFree());
        }
        private async Task <ImmutableArray <CodeFix> > GetSuppressionsAsync(
            Document documentOpt, Project project, IEnumerable <Diagnostic> diagnostics, SuppressionTargetInfo suppressionTargetInfo, bool skipSuppressMessage, bool skipUnsuppress, CancellationToken cancellationToken)
        {
            // We only care about diagnostics that can be suppressed/unsuppressed.
            diagnostics = diagnostics.Where(IsFixableDiagnostic);
            if (diagnostics.IsEmpty())
            {
                return(ImmutableArray <CodeFix> .Empty);
            }

            if (!skipSuppressMessage)
            {
                var compilation = await project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);

                var suppressMessageAttribute = compilation.SuppressMessageAttributeType();
                skipSuppressMessage = suppressMessageAttribute == null || !suppressMessageAttribute.IsAttribute();
            }

            var result = ArrayBuilder <CodeFix> .GetInstance();

            foreach (var diagnostic in diagnostics)
            {
                if (!diagnostic.IsSuppressed)
                {
                    var nestedActions = ArrayBuilder <NestedSuppressionCodeAction> .GetInstance();

                    if (diagnostic.Location.IsInSource && documentOpt != null)
                    {
                        // pragma warning disable.
                        nestedActions.Add(PragmaWarningCodeAction.Create(suppressionTargetInfo, documentOpt, diagnostic, this));
                    }

                    // SuppressMessageAttribute suppression is not supported for compiler diagnostics.
                    if (!skipSuppressMessage && !SuppressionHelpers.IsCompilerDiagnostic(diagnostic))
                    {
                        // global assembly-level suppress message attribute.
                        nestedActions.Add(new GlobalSuppressMessageCodeAction(suppressionTargetInfo.TargetSymbol, project, diagnostic, this));

                        // local suppress message attribute
                        // please note that in order to avoid issues with exising unit tests referencing the code fix
                        // by their index this needs to be the last added to nestedActions
                        if (suppressionTargetInfo.TargetMemberNode != null && suppressionTargetInfo.TargetSymbol.Kind != SymbolKind.Namespace)
                        {
                            nestedActions.Add(new LocalSuppressMessageCodeAction(this, suppressionTargetInfo.TargetSymbol, suppressionTargetInfo.TargetMemberNode, documentOpt, diagnostic));
                        }
                    }

                    if (nestedActions.Count > 0)
                    {
                        var codeAction = new TopLevelSuppressionCodeAction(
                            diagnostic, nestedActions.ToImmutableAndFree());
                        result.Add(new CodeFix(project, codeAction, diagnostic));
                    }
                }
                else if (!skipUnsuppress)
                {
                    var codeAction = await RemoveSuppressionCodeAction.CreateAsync(suppressionTargetInfo, documentOpt, project, diagnostic, this, cancellationToken).ConfigureAwait(false);

                    if (codeAction != null)
                    {
                        result.Add(new CodeFix(project, codeAction, diagnostic));
                    }
                }
            }

            return(result.ToImmutableAndFree());
        }