private static void CreateAndPlaceDisposeCallAfterLastUsage(string variableName, BlockSyntax parentBlock,
StatementSyntax lastUsageStatement, SyntaxEditor editor)
{
var disposeCall = SyntaxCreator.CreateDisposeCallFor(variableName);
var statementsBeforeLastUsage = parentBlock.Statements
.TakeWhile(s => s != lastUsageStatement);
var statementsAfterLastUsage = parentBlock.Statements
.SkipWhile(s => s != lastUsageStatement)
.Skip(1);
var newBlock = SyntaxFactory.Block(
statementsBeforeLastUsage
.Concat(lastUsageStatement)
.Concat(disposeCall)
.Concat(statementsAfterLastUsage)
).WithoutAnnotations(Formatter.Annotation);
editor.ReplaceNode(parentBlock, newBlock);
}
private static ExpressionStatementSyntax CreateDisposeCall(string memberName, bool castToIDisposable)
{
if (castToIDisposable)
{
return(SyntaxFactory.ExpressionStatement(
SyntaxFactory.ConditionalAccessExpression(
SyntaxFactory.ParenthesizedExpression(
SyntaxFactory.BinaryExpression(
SyntaxKind.AsExpression,
SyntaxFactory.IdentifierName(memberName),
SyntaxFactory.IdentifierName(Constants.IDisposable))
.WithOperatorToken(
SyntaxFactory.Token(SyntaxKind.AsKeyword)))
.WithOpenParenToken(
SyntaxFactory.Token(SyntaxKind.OpenParenToken))
.WithCloseParenToken(
SyntaxFactory.Token(SyntaxKind.CloseParenToken)),
SyntaxFactory.InvocationExpression(
SyntaxFactory.MemberBindingExpression(
SyntaxFactory.IdentifierName(Constants.Dispose))
.WithOperatorToken(
SyntaxFactory.Token(SyntaxKind.DotToken)))
.WithArgumentList(
SyntaxFactory.ArgumentList()
.WithOpenParenToken(
SyntaxFactory.Token(SyntaxKind.OpenParenToken))
.WithCloseParenToken(
SyntaxFactory.Token(SyntaxKind.CloseParenToken))))
.WithOperatorToken(
SyntaxFactory.Token(SyntaxKind.QuestionToken)))
.WithSemicolonToken(
SyntaxFactory.Token(SyntaxKind.SemicolonToken)));
}
return(SyntaxCreator.CreateConditionalAccessDisposeCallFor(memberName));
}
private static async Task <Document> Apply(CodeFixContext context, CancellationToken cancel)
{
var editor = await DocumentEditor.CreateAsync(context.Document, cancel);
var node = editor.OriginalRoot.FindNode(context.Span);
var variableName = FindVariableName(node);
if (node.TryFindContainigBlock(out var parentBlock))
{
var lastUsage = parentBlock
.DescendantNodes <VariableDeclaratorSyntax>()
.Last(ins => ins.Identifier.Text == variableName);
if (lastUsage.TryFindParent <StatementSyntax>(parentBlock, out var lastUsageStatement))
{
var disposeCall = SyntaxCreator.CreateDisposeCallFor(variableName);
var statementsBeforeLastUsage = parentBlock.Statements
.TakeWhile(s => s != lastUsageStatement);
var statementsAfterLastUsage = parentBlock.Statements
.SkipWhile(s => s != lastUsageStatement)
.Skip(1);
var newBlock = SyntaxFactory.Block(
statementsBeforeLastUsage
.Concat(lastUsageStatement)
.Concat(disposeCall)
.Concat(statementsAfterLastUsage)
).WithoutAnnotations(Formatter.Annotation);
editor.ReplaceNode(parentBlock, newBlock);
return(editor.GetChangedDocument());
}
}
return(context.Document);
}
