private async Task<Document> InsertStopwatchToMeasureTime(Document document, IdentifierNameSyntax node, CancellationToken cancellationToken) {
SemanticModel semanticModel = await document.GetSemanticModelAsync(cancellationToken);
var nodes = new List<Tuple<SyntaxNode, SyntaxNode>>();
SyntaxNode nodeLine = GetRootNodeOfLine(node);
SyntaxNode newNode = CommentLine(nodeLine);
newNode = newNode.WithTrailingTrivia(newNode.GetTrailingTrivia()
.AddRange(nodeLine.GetLeadingTrivia())
.Add(SyntaxFactory.SyntaxTrivia(SyntaxKind.SingleLineCommentTrivia, "timer.Stop();"))
.Add(SyntaxFactory.EndOfLine(Environment.NewLine))
.AddRange(nodeLine.GetLeadingTrivia())
.Add(SyntaxFactory.SyntaxTrivia(SyntaxKind.SingleLineCommentTrivia, "TimeSpan elapsed = timer.Elapsed;"))
.Add(SyntaxFactory.EndOfLine(Environment.NewLine)));
nodes.Add(new Tuple<SyntaxNode, SyntaxNode>(nodeLine, newNode));
var methodDeclaration = node.FirstAncestorOfType(typeof(MethodDeclarationSyntax)) as MethodDeclarationSyntax;
if (semanticModel == null) { return document; }
SyntaxNode firstGetTime = TimeMeasurementCodeAnalyzer.GetNodesUsedToGetCurrentTime(semanticModel, methodDeclaration).First();
nodeLine = GetRootNodeOfLine(firstGetTime);
newNode = CommentLine(nodeLine);
newNode = newNode.WithTrailingTrivia(newNode.GetTrailingTrivia()
.AddRange(nodeLine.GetLeadingTrivia())
.Add(SyntaxFactory.SyntaxTrivia(SyntaxKind.SingleLineCommentTrivia, "var timer = Stopwatch.StartNew();"))
.Add(SyntaxFactory.EndOfLine(Environment.NewLine)));
nodes.Add(new Tuple<SyntaxNode, SyntaxNode>(nodeLine, newNode));
document = await this.ReplaceNodesInDocumentAsync(document, cancellationToken, nodes.ToArray());
return await this.CheckNamespaceUsageAsync(document, cancellationToken, "System.Diagnostics");
}
