/// <summary>
/// Reads an expression wrapped in parenthesis expression.
/// </summary>
/// <param name="unsafeCode">Indicates whether the code being parsed resides in an unsafe code block.</param>
/// <returns>Returns the expression.</returns>
private ParenthesizedExpression GetParenthesizedExpression(bool unsafeCode)
{
Param.Ignore(unsafeCode);
var expressionReference = new Reference<ICodePart>();
// Get the opening parenthesis.
Bracket openParenthesis = this.GetBracketToken(CsTokenType.OpenParenthesis, SymbolType.OpenParenthesis, expressionReference);
Node<CsToken> openParenthesisNode = this.tokens.InsertLast(openParenthesis);
// Get the inner expression.
Expression innerExpression = this.GetNextExpression(ExpressionPrecedence.None, expressionReference, unsafeCode);
if (innerExpression == null)
{
throw this.CreateSyntaxException();
}
// Get the closing parenthesis.
Bracket closeParenthesis = this.GetBracketToken(CsTokenType.CloseParenthesis, SymbolType.CloseParenthesis, expressionReference);
Node<CsToken> closeParenthesisNode = this.tokens.InsertLast(closeParenthesis);
openParenthesis.MatchingBracketNode = closeParenthesisNode;
closeParenthesis.MatchingBracketNode = openParenthesisNode;
// Create the token list for the expression.
CsTokenList partialTokens = new CsTokenList(this.tokens, openParenthesisNode, this.tokens.Last);
// Create and return the expression.
var expression = new ParenthesizedExpression(partialTokens, innerExpression);
expressionReference.Target = expression;
return expression;
}
/// <summary>
/// Reads an expression wrapped in parenthesis.
/// </summary>
/// <param name="sourceCode">The source code containing the expression.</param>
/// <param name="parentReference">The parent code part.</param>
/// <returns>Returns the expression.</returns>
private ParenthesizedExpression GetConditionalPreprocessorParenthesizedExpression(
SourceCode sourceCode, Reference<ICodePart> parentReference)
{
Param.AssertNotNull(sourceCode, "sourceCode");
Param.AssertNotNull(parentReference, "parentReference");
// Get the opening parenthesis.
this.AdvanceToNextConditionalDirectiveCodeSymbol(parentReference);
Symbol firstSymbol = this.symbols.Peek(1);
if (firstSymbol == null || firstSymbol.SymbolType != SymbolType.OpenParenthesis)
{
throw new SyntaxException(sourceCode, firstSymbol.LineNumber);
}
var expressionReference = new Reference<ICodePart>();
this.symbols.Advance();
Bracket openParenthesis = new Bracket(
firstSymbol.Text, CsTokenType.OpenParenthesis, firstSymbol.Location, expressionReference, this.symbols.Generated);
Node<CsToken> openParenthesisNode = this.tokens.InsertLast(openParenthesis);
// Get the inner expression.
Expression innerExpression = this.GetNextConditionalPreprocessorExpression(sourceCode, ExpressionPrecedence.None);
if (innerExpression == null)
{
throw new SyntaxException(sourceCode, firstSymbol.LineNumber);
}
// Get the closing parenthesis.
this.AdvanceToNextConditionalDirectiveCodeSymbol(expressionReference);
Symbol symbol = this.symbols.Peek(1);
if (symbol == null || symbol.SymbolType != SymbolType.CloseParenthesis)
{
throw new SyntaxException(sourceCode, firstSymbol.LineNumber);
}
this.symbols.Advance();
Bracket closeParenthesis = new Bracket(
symbol.Text, CsTokenType.CloseParenthesis, symbol.Location, expressionReference, this.symbols.Generated);
Node<CsToken> closeParenthesisNode = this.tokens.InsertLast(closeParenthesis);
openParenthesis.MatchingBracketNode = closeParenthesisNode;
closeParenthesis.MatchingBracketNode = openParenthesisNode;
// Create the token list for the expression.
CsTokenList partialTokens = new CsTokenList(this.tokens, openParenthesisNode, this.tokens.Last);
// Create and return the expression.
var expression = new ParenthesizedExpression(partialTokens, innerExpression);
expressionReference.Target = expression;
return expression;
}
private void CheckParenthesizedExpression(CsElement element, ParenthesizedExpression parenthesizedExpression)
{
if (parenthesizedExpression.InnerExpression != null)
{
Expression innerExpression = parenthesizedExpression.InnerExpression;
if ((((((innerExpression.ExpressionType != ExpressionType.Arithmetic) && (innerExpression.ExpressionType != ExpressionType.As)) && ((innerExpression.ExpressionType != ExpressionType.Assignment) && (innerExpression.ExpressionType != ExpressionType.Cast))) && (((innerExpression.ExpressionType != ExpressionType.Conditional) && (innerExpression.ExpressionType != ExpressionType.ConditionalLogical)) && ((innerExpression.ExpressionType != ExpressionType.Decrement) && (innerExpression.ExpressionType != ExpressionType.Increment)))) && ((((innerExpression.ExpressionType != ExpressionType.Is) && (innerExpression.ExpressionType != ExpressionType.Lambda)) && ((innerExpression.ExpressionType != ExpressionType.Logical) && (innerExpression.ExpressionType != ExpressionType.New))) && (((innerExpression.ExpressionType != ExpressionType.NewArray) && (innerExpression.ExpressionType != ExpressionType.NullCoalescing)) && ((innerExpression.ExpressionType != ExpressionType.Query) && (innerExpression.ExpressionType != ExpressionType.Relational))))) && (innerExpression.ExpressionType != ExpressionType.Unary))
{
base.AddViolation(element, parenthesizedExpression.LineNumber, Microsoft.StyleCop.CSharp.Rules.StatementMustNotUseUnnecessaryParenthesis, new object[0]);
}
else if (!(parenthesizedExpression.Parent is Expression) || (parenthesizedExpression.Parent is VariableDeclaratorExpression))
{
base.AddViolation(element, parenthesizedExpression.LineNumber, Microsoft.StyleCop.CSharp.Rules.StatementMustNotUseUnnecessaryParenthesis, new object[0]);
}
else
{
AssignmentExpression parent = parenthesizedExpression.Parent as AssignmentExpression;
if ((parent != null) && (parent.RightHandSide == parenthesizedExpression))
{
base.AddViolation(element, parenthesizedExpression.LineNumber, Microsoft.StyleCop.CSharp.Rules.StatementMustNotUseUnnecessaryParenthesis, new object[0]);
}
}
}
}
/// <summary>
/// Checks the given parenthesized expression to make sure that it is not unnecessary.
/// </summary>
/// <param name="element">The element containing the expression.</param>
/// <param name="parenthesizedExpression">The parenthesized expression to check.</param>
private void CheckParenthesizedExpression(CsElement element, ParenthesizedExpression parenthesizedExpression)
{
Param.AssertNotNull(element, "element");
Param.AssertNotNull(parenthesizedExpression, "parenthesizedExpression");
// Check the type of the inner expression to determine if it is one of types allowed to be wrapped within parenthesis.
if (parenthesizedExpression.InnerExpression != null)
{
// The following types of expressions are allowed to be placed within a set of parenthesis.
Expression innerExpression = parenthesizedExpression.InnerExpression;
if (innerExpression.ExpressionType != ExpressionType.Arithmetic &&
innerExpression.ExpressionType != ExpressionType.As &&
innerExpression.ExpressionType != ExpressionType.Assignment &&
innerExpression.ExpressionType != ExpressionType.Cast &&
innerExpression.ExpressionType != ExpressionType.Conditional &&
innerExpression.ExpressionType != ExpressionType.ConditionalLogical &&
innerExpression.ExpressionType != ExpressionType.Decrement &&
innerExpression.ExpressionType != ExpressionType.Increment &&
innerExpression.ExpressionType != ExpressionType.Is &&
innerExpression.ExpressionType != ExpressionType.Lambda &&
innerExpression.ExpressionType != ExpressionType.Logical &&
innerExpression.ExpressionType != ExpressionType.New &&
innerExpression.ExpressionType != ExpressionType.NewArray &&
innerExpression.ExpressionType != ExpressionType.NullCoalescing &&
innerExpression.ExpressionType != ExpressionType.Query &&
innerExpression.ExpressionType != ExpressionType.Relational &&
innerExpression.ExpressionType != ExpressionType.Unary &&
innerExpression.ExpressionType != ExpressionType.UnsafeAccess)
{
this.AddViolation(element, parenthesizedExpression.LineNumber, Rules.StatementMustNotUseUnnecessaryParenthesis);
}
else
{
// These types of expressions are allowed in some cases to be surrounded by parenthesis,
// as long as the parenthesized expression is within another expression. They are not allowed
// to be within parenthesis within a variable declarator expression. For example:
// int x = (2 + 3);
if (!(parenthesizedExpression.Parent is Expression)
|| parenthesizedExpression.Parent is VariableDeclaratorExpression
|| parenthesizedExpression.Parent is CheckedExpression
|| parenthesizedExpression.Parent is UncheckedExpression)
{
this.AddViolation(element, parenthesizedExpression.LineNumber, Rules.StatementMustNotUseUnnecessaryParenthesis);
}
else
{
// This is also not allowed when the expression is on the right-hand side of an assignment.
AssignmentExpression assignment = parenthesizedExpression.Parent as AssignmentExpression;
if (assignment != null && assignment.RightHandSide == parenthesizedExpression)
{
this.AddViolation(element, parenthesizedExpression.LineNumber, Rules.StatementMustNotUseUnnecessaryParenthesis);
}
}
}
}
}