public override async Task ComputeRefactoringsAsync(CodeRefactoringContext context)
{
var(document, _, cancellationToken) = context;
var calleeInvocationNode = await context.TryGetRelevantNodeAsync <TInvocationSyntax>().ConfigureAwait(false);
if (calleeInvocationNode == null)
{
return;
}
var semanticModel = await document.GetRequiredSemanticModelAsync(cancellationToken).ConfigureAwait(false);
var calleeMethodSymbol = semanticModel.GetSymbolInfo(calleeInvocationNode, cancellationToken).GetAnySymbol() as IMethodSymbol;
if (calleeMethodSymbol == null)
{
return;
}
if (calleeMethodSymbol.PartialImplementationPart != null)
{
calleeMethodSymbol = calleeMethodSymbol.PartialImplementationPart;
}
if (!calleeMethodSymbol.IsOrdinaryMethod() && !calleeMethodSymbol.IsExtensionMethod)
{
return;
}
if (calleeMethodSymbol.IsVararg)
{
return;
}
if (calleeMethodSymbol.DeclaredAccessibility != Accessibility.Private)
{
return;
}
var symbolDeclarationService = document.GetRequiredLanguageService <ISymbolDeclarationService>();
var calleeMethodDeclarationSyntaxReferences = symbolDeclarationService.GetDeclarations(calleeMethodSymbol);
if (calleeMethodDeclarationSyntaxReferences.Length != 1)
{
return;
}
var calleeMethodDeclarationSyntaxReference = calleeMethodDeclarationSyntaxReferences[0];
var calleeMethodNode = await calleeMethodDeclarationSyntaxReference.GetSyntaxAsync(cancellationToken).ConfigureAwait(false) as TMethodDeclarationSyntax;
if (calleeMethodNode == null)
{
return;
}
var inlineExpression = GetRawInlineExpression(calleeMethodNode);
// Special case 1: AwaitExpression
if (_syntaxFacts.IsAwaitExpression(inlineExpression))
{
// 1. If Caller & callee both have 'await' make sure there is no duplicate 'await'
// Example:
// Before:
// async Task Caller() => await Callee();
// async Task Callee() => await Task.CompletedTask;
// After:
// async Task Caller() => await Task.CompletedTask;
// async Task Callee() => await Task.CompletedTask;
// The original inline expression in callee will be 'await Task.CompletedTask'
// The caller just need 'Task.CompletedTask' without the 'await'
//
// 2. If Caller doesn't have await but callee has.
// Example:
// Before:
// void Caller() { Callee().Wait();}
// async Task Callee() => await DoAsync();
// After:
// void Caller() { DoAsync().Wait(); }
// async Task Callee() => await DoAsync();
// What caller is expecting is an expression returns 'Task', which doesn't include the 'await'
inlineExpression = _syntaxFacts.GetExpressionOfAwaitExpression(inlineExpression) as TExpressionSyntax;
}
if (inlineExpression == null)
{
return;
}
// Special case 2: ThrowStatement & ThrowExpresion
if (_syntaxFacts.IsThrowStatement(inlineExpression.Parent) || _syntaxFacts.IsThrowExpression(inlineExpression))
{
// If this is a throw statement, then it should be valid for
// 1. If it is invoked as ExpressionStatement
// Example:
// Before:
// void Caller() { Callee(); }
// void Callee() { throw new Exception();}
// After:
// void Caller() { throw new Exception(); }
// void Callee() { throw new Exception();}
// 2. If it is invoked in a place allow throw expression
// Example:
// Before:
// void Caller(bool flag) { var x = flag ? Callee() : 1; }
// int Callee() { throw new Exception();}
// After:
// void Caller() { var x = flag ? throw new Exception() : 1; }
// int Callee() { throw new Exception();}
// Note here throw statement is changed to throw expression after inlining
// If this is a throw expression, the check is the same
// 1. If it is invoked as ExpressionStatement
// Example:
// Before:
// void Caller() { Callee(); }
// void Callee() => throw new Exception();
// After:
// void Caller() { throw new Exception(); }
// void Callee() => throw new Exception();
// Note here throw expression is converted to throw statement
// 2. If it is invoked in a place allow throw expression
// Example:
// Before:
// void Caller(bool flag) { var x = flag ? Callee() : 1; }
// int Callee() => throw new Exception();
// After:
// void Caller() { var x = flag ? throw new Exception() : 1; }
// int Callee() => throw new Exception();
if (!CanBeReplacedByThrowExpression(calleeInvocationNode) &&
!_syntaxFacts.IsExpressionStatement(calleeInvocationNode.Parent))
{
return;
}
}
var callerSymbol = GetCallerSymbol(calleeInvocationNode, semanticModel, cancellationToken);
if (callerSymbol == null)
{
return;
}
var callerReferences = symbolDeclarationService.GetDeclarations(callerSymbol);
if (callerReferences.Length != 1)
{
return;
}
var callerDeclarationNode = await callerReferences[0].GetSyntaxAsync(cancellationToken).ConfigureAwait(false);
var invocationOperation = semanticModel.GetOperation(calleeInvocationNode, cancellationToken) as IInvocationOperation;
if (invocationOperation == null)
{
return;
}
var codeActions = GenerateCodeActions(
document,
calleeInvocationNode,
calleeMethodSymbol,
calleeMethodNode,
callerSymbol,
callerDeclarationNode,
inlineExpression, invocationOperation);
var nestedCodeAction = CodeAction.CodeActionWithNestedActions.Create(
string.Format(FeaturesResources.Inline_0, calleeMethodSymbol.ToNameDisplayString()),
codeActions,
isInlinable: true);
context.RegisterRefactoring(nestedCodeAction, calleeInvocationNode.Span);
}