public override void VisitLambdaExpression(LambdaExpression lambdaExpression)
{
base.VisitLambdaExpression(lambdaExpression);
BlockStatement block;
Expression expr;
if (!ConvertLambdaBodyStatementToExpressionAction.TryGetConvertableExpression(lambdaExpression.Body, out block, out expr))
{
return;
}
var node = block.Statements.FirstOrDefault() ?? block;
var expressionStatement = node as ExpressionStatement;
if (expressionStatement != null)
{
if (expressionStatement.Expression is AssignmentExpression)
{
return;
}
}
var returnTypes = new List <IType>();
foreach (var type in TypeGuessing.GetValidTypes(ctx.Resolver, lambdaExpression))
{
if (type.Kind != TypeKind.Delegate)
{
continue;
}
var invoke = type.GetDelegateInvokeMethod();
if (!returnTypes.Contains(invoke.ReturnType))
{
returnTypes.Add(invoke.ReturnType);
}
}
if (returnTypes.Count > 1)
{
return;
}
// can't convert return statements without expression.
var returnExpr = node as ReturnStatement;
if (returnExpr != null && returnExpr.Expression.IsNull)
{
return;
}
AddIssue(new CodeIssue(
node,
ctx.TranslateString("Can be converted to expression"),
ConvertLambdaBodyStatementToExpressionAction.CreateAction(ctx, node, block, expr)
));
}
public override void VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression)
{
base.VisitAnonymousMethodExpression(anonymousMethodExpression);
if (!anonymousMethodExpression.HasParameterList)
{
return;
}
BlockStatement block;
Expression expr;
if (!ConvertLambdaBodyStatementToExpressionAction.TryGetConvertableExpression(anonymousMethodExpression.Body, out block, out expr))
{
return;
}
var node = block.Statements.FirstOrDefault() ?? block;
var returnTypes = new List <IType>();
foreach (var type in TypeGuessing.GetValidTypes(ctx.Resolver, anonymousMethodExpression))
{
if (type.Kind != TypeKind.Delegate)
{
continue;
}
var invoke = type.GetDelegateInvokeMethod();
if (!returnTypes.Contains(invoke.ReturnType))
{
returnTypes.Add(invoke.ReturnType);
}
}
if (returnTypes.Count > 1)
{
return;
}
AddIssue(new CodeIssue(
node,
ctx.TranslateString("Can be converted to expression"),
ctx.TranslateString("Convert to lambda expression"),
script => {
var lambdaExpression = new LambdaExpression();
foreach (var parameter in anonymousMethodExpression.Parameters)
{
lambdaExpression.Parameters.Add(parameter.Clone());
}
lambdaExpression.Body = expr.Clone();
script.Replace(anonymousMethodExpression, lambdaExpression);
}
));
}
