Simple Dynamics CRM code fix using the .NET Compiler Platform ("Roslyn")

BasicBracketedArgumentListCodeFix.cs

public sealed override async Task ComputeFixesAsync(CodeFixContext context)
{
	var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken).ConfigureAwait(false);

	var diagnostic = context.Diagnostics.First();
	var diagnosticSpan = diagnostic.Location.SourceSpan;

	// Find the type declaration identified by the diagnostic.
	var declaration = root.FindToken(diagnosticSpan.Start).Parent;

	// Register a code action that will invoke the fix.
	context.RegisterFix(
		CodeAction.Create("Make lowercase", c => MakeLowercaseAsync(context.Document, declaration, c)),
		diagnostic);
}

private async Task<Document> MakeLowercaseAsync(Document document, SyntaxNode node, CancellationToken cancellationToken)
{
	var root = await document.GetSyntaxRootAsync(cancellationToken);
	BracketedArgumentListSyntax bal = (BracketedArgumentListSyntax)node;
	var newFieldName = bal.Arguments.FirstOrDefault().ToString().ToLowerInvariant();

	var newNode = SyntaxFactory.BracketedArgumentList(SyntaxFactory.SeparatedList<ArgumentSyntax>().Add(
				SyntaxFactory.Argument(null, SyntaxFactory.Token(SyntaxKind.None),
				SyntaxFactory.IdentifierName(newFieldName))));

	var newRoot = root.ReplaceNode(node, newNode);

	return document.WithSyntaxRoot(newRoot);
}