private static Task <Document> ConvertWhileStatementToForStatementAsync(
Document document,
WhileStatementSyntax whileStatement,
CancellationToken cancellationToken)
{
StatementListInfo statementsInfo = SyntaxInfo.StatementListInfo(whileStatement);
SyntaxList <StatementSyntax> statements = statementsInfo.Statements;
int index = statements.IndexOf(whileStatement);
SingleLocalDeclarationStatementInfo localInfo = SyntaxInfo.SingleLocalDeclarationStatementInfo((LocalDeclarationStatementSyntax)statements[index - 1]);
var block = (BlockSyntax)whileStatement.Statement;
var expressionStatement = (ExpressionStatementSyntax)block.Statements.Last();
var postIncrementExpression = (PostfixUnaryExpressionSyntax)expressionStatement.Expression;
BlockSyntax newBlock = block.WithStatements(block.Statements.Remove(expressionStatement));
ForStatementSyntax forStatement = CSharpFactory.ForStatement(
declaration: localInfo.Declaration.TrimTrivia(),
condition: whileStatement.Condition,
incrementor: postIncrementExpression.TrimTrivia(),
statement: newBlock);
forStatement = forStatement
.WithLeadingTrivia(localInfo.Statement.GetLeadingTrivia().AddRange(whileStatement.GetLeadingTrivia().EmptyIfWhitespace()))
.WithFormatterAnnotation();
SyntaxList <StatementSyntax> newStatements = statements.ReplaceRange(index - 1, 2, new StatementSyntax[] { forStatement });
return(document.ReplaceStatementsAsync(statementsInfo, newStatements, cancellationToken));
}