private async Task<Document> MakeConstAsync(Document document, LocalDeclarationStatementSyntax localDeclaration, CancellationToken cancellationToken)
{
var firstToken = localDeclaration.GetFirstToken();
var leadingTrivia = firstToken.LeadingTrivia;
var trimmedLocal = localDeclaration.ReplaceToken(firstToken, firstToken.WithLeadingTrivia(SyntaxTriviaList.Empty));
var constToken = SyntaxFactory.Token(leadingTrivia, SyntaxKind.ConstKeyword, SyntaxFactory.TriviaList(SyntaxFactory.ElasticMarker));
var newModifiers = trimmedLocal.Modifiers.Insert(0, constToken);
var variableDeclaration = localDeclaration.Declaration;
var variableTypeName = variableDeclaration.Type;
if (variableTypeName.IsVar)
{
var semanticModel = await document.GetSemanticModelAsync(cancellationToken);
var aliasInfo = semanticModel.GetAliasInfo(variableTypeName);
if (aliasInfo == null)
{
var type = semanticModel.GetTypeInfo(variableTypeName).ConvertedType;
if (type.Name != "var")
{
var typeName = SyntaxFactory.ParseTypeName(type.ToDisplayString())
.WithLeadingTrivia(variableTypeName.GetLeadingTrivia())
.WithTrailingTrivia(variableTypeName.GetTrailingTrivia());
var simplifiedTypeName = typeName.WithAdditionalAnnotations(Simplifier.Annotation);
variableDeclaration = variableDeclaration.WithType(simplifiedTypeName);
}
}
}
var newLocal = trimmedLocal.WithModifiers(newModifiers)
.WithDeclaration(variableDeclaration);
var formattedLocal = newLocal.WithAdditionalAnnotations(Formatter.Annotation);
var root = await document.GetSyntaxRootAsync(cancellationToken);
var newRoot = root.ReplaceNode(localDeclaration, formattedLocal);
return document.WithSyntaxRoot(newRoot);
}
private async Task<Document> MakeConstAsync(Document document, LocalDeclarationStatementSyntax localDeclaration, CancellationToken cancellationToken)
{
// Remove the leading trivia from the local declaration.
var firstToken = localDeclaration.GetFirstToken();
var leadingTrivia = firstToken.LeadingTrivia;
var trimmedLocal = localDeclaration.ReplaceToken(
firstToken, firstToken.WithLeadingTrivia(SyntaxTriviaList.Empty));
// Create a const token with the leading trivia.
var constToken = SyntaxFactory.Token(leadingTrivia, SyntaxKind.ConstKeyword, SyntaxFactory.TriviaList(SyntaxFactory.ElasticMarker));
// Insert the const token into the modifiers list, creating a new modifiers list.
var newModifiers = trimmedLocal.Modifiers.Insert(0, constToken);
// If the type of declaration is 'var', create a new type name for the
// type inferred for 'var'.
var variableDeclaration = localDeclaration.Declaration;
var variableTypeName = variableDeclaration.Type;
if (variableTypeName.IsVar)
{
var semanticModel = await document.GetSemanticModelAsync(cancellationToken);
// Special case: Ensure that 'var' isn't actually an alias to another type
// (e.g. using var = System.String).
var aliasInfo = semanticModel.GetAliasInfo(variableTypeName);
if (aliasInfo == null)
{
// Retrieve the type inferred for var.
var type = semanticModel.GetTypeInfo(variableTypeName).ConvertedType;
// Special case: Ensure that 'var' isn't actually a type named 'var'.
if (type.Name != "var")
{
// Create a new TypeSyntax for the inferred type. Be careful
// to keep any leading and trailing trivia from the var keyword.
var typeName = SyntaxFactory.ParseTypeName(type.ToDisplayString())
.WithLeadingTrivia(variableTypeName.GetLeadingTrivia())
.WithTrailingTrivia(variableTypeName.GetTrailingTrivia());
// Add an annotation to simplify the type name.
var simplifiedTypeName = typeName.WithAdditionalAnnotations(Simplifier.Annotation);
// Replace the type in the variable declaration.
variableDeclaration = variableDeclaration.WithType(simplifiedTypeName);
}
}
}
// Produce the new local declaration.
var newLocal = trimmedLocal.WithModifiers(newModifiers)
.WithDeclaration(variableDeclaration);
// Add an annotation to format the new local declaration.
var formattedLocal = newLocal.WithAdditionalAnnotations(Formatter.Annotation);
// Replace the old local declaration with the new local declaration.
var root = await document.GetSyntaxRootAsync(cancellationToken);
var newRoot = root.ReplaceNode(localDeclaration, formattedLocal);
// Return document with transformed tree.
return document.WithSyntaxRoot(newRoot);
}