private static LambdaExpressionSyntax UpdateWorker(
SemanticModel semanticModel, LambdaExpressionSyntax originalDeclaration, LambdaExpressionSyntax currentDeclaration)
{
var expressionBody = UseExpressionBodyForLambdaHelpers.GetBodyAsExpression(currentDeclaration);
return(expressionBody == null
? WithExpressionBody(currentDeclaration, originalDeclaration.GetLanguageVersion())
: WithBlockBody(semanticModel, originalDeclaration, currentDeclaration, expressionBody));
}
private static LambdaExpressionSyntax WithExpressionBody(LambdaExpressionSyntax declaration, LanguageVersion languageVersion)
{
if (!UseExpressionBodyForLambdaHelpers.TryConvertToExpressionBody(declaration, languageVersion, ExpressionBodyPreference.WhenPossible, out var expressionBody))
{
return(declaration);
}
var updatedDecl = declaration.WithBody(expressionBody);
// If there will only be whitespace between the arrow and the body, then replace that
// with a single space so that the lambda doesn't have superfluous newlines in it.
if (declaration.ArrowToken.TrailingTrivia.All(t => t.IsWhitespaceOrEndOfLine()) &&
expressionBody.GetLeadingTrivia().All(t => t.IsWhitespaceOrEndOfLine()))
{
updatedDecl = updatedDecl.WithArrowToken(updatedDecl.ArrowToken.WithTrailingTrivia(SyntaxFactory.ElasticSpace));
}
return(updatedDecl);
}
