internal static AnalysisResult InvokesPropertyChangedFor(ExpressionSyntax mutation, IPropertySymbol property, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (mutation.Parent is ArgumentSyntax {
Parent : ArgumentListSyntax {
Parent : InvocationExpressionSyntax invocation
}
} argument&&
argument.RefOrOutKeyword.IsKind(SyntaxKind.RefKeyword) &&
invocation.IsPotentialThisOrBase())
{
if (TrySet.IsMatch(invocation, semanticModel, cancellationToken) != AnalysisResult.No &&
semanticModel.GetSymbolSafe(invocation, cancellationToken) is { } setAndRaiseMethod&&
setAndRaiseMethod.Parameters.TryLast(x => x.Type == KnownSymbol.String, out var nameParameter))
{
if (invocation.TryFindArgument(nameParameter, out var nameArg))
{
if (nameArg.TryGetStringValue(semanticModel, cancellationToken, out var name))
{
if (string.IsNullOrEmpty(name) ||
name == property.Name)
{
return(AnalysisResult.Yes);
}
}
}
else if (invocation.FirstAncestor <PropertyDeclarationSyntax>() is { } propertyDeclaration&&
propertyDeclaration.Identifier.ValueText == property.Name)
{
return(AnalysisResult.Yes);
}
}
protected override async Task RegisterCodeFixesAsync(DocumentEditorCodeFixContext context)
{
var syntaxRoot = await context.Document.GetSyntaxRootAsync(context.CancellationToken)
.ConfigureAwait(false);
var semanticModel = await context.Document.GetSemanticModelAsync(context.CancellationToken)
.ConfigureAwait(false);
foreach (var diagnostic in context.Diagnostics)
{
if (syntaxRoot.TryFindNodeOrAncestor(diagnostic, out ExpressionStatementSyntax? onPropertyChangedStatement) &&
onPropertyChangedStatement.TryFirstAncestor(out AccessorDeclarationSyntax? setter) &&
setter.IsKind(SyntaxKind.SetAccessorDeclaration) &&
setter.Body is { } body)
{
if (Setter.TryFindSingleAssignment(setter, out var assignment) &&
assignment.Parent is ExpressionStatementSyntax assignmentStatement &&
body.Statements.IndexOf(assignmentStatement) == 0)
{
if (semanticModel.TryGetSymbol(assignment.Left, CancellationToken.None, out var assignedSymbol) &&
assignedSymbol.Kind == SymbolKind.Field &&
semanticModel.TryGetSymbol(setter, context.CancellationToken, out IMethodSymbol? setterSymbol) &&
TrySet.TryFind(setterSymbol.ContainingType, semanticModel, context.CancellationToken, out var trySetMethod) &&
TrySet.CanCreateInvocation(trySetMethod, out _) &&
setter.TryFirstAncestor(out PropertyDeclarationSyntax? property))
{
if (setter.Body.Statements.Count == 2)
{
context.RegisterCodeFix(
trySetMethod.DisplaySignature(),
async(editor, cancellationToken) =>
{
var trySet = await editor.TrySetInvocationAsync(trySetMethod, assignment.Left, assignment.Right, property, cancellationToken)
.ConfigureAwait(false);
_ = editor.ReplaceNode(
setter,
x => x.AsExpressionBody(trySet));
},
trySetMethod.MetadataName,
diagnostic);
}
}
context.RegisterCodeFix(
"Check that value is different before notifying.",
(editor, cancellationToken) => editor.InsertBefore(
assignmentStatement,
InpcFactory.IfReturn(
InpcFactory.Equals(
assignment.Right,
assignment.Left,
editor.SemanticModel,
cancellationToken))),
nameof(CheckIfDifferentBeforeNotifyFix),
diagnostic);
}
internal static bool TryFindSingleTrySet(AccessorDeclarationSyntax setter, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out InvocationExpressionSyntax?invocation)
{
invocation = null;
if (setter == null)
{
return(false);
}
using var walker = InvocationWalker.Borrow(setter);
return(walker.Invocations.TrySingle <InvocationExpressionSyntax>(x => TrySet.IsMatch(x, semanticModel, cancellationToken) != AnalysisResult.No, out invocation));
}
private static void Handle(SyntaxNodeAnalysisContext context)
{
if (!context.IsExcludedFromAnalysis() &&
context.ContainingSymbol is IMethodSymbol method &&
context.Node is MethodDeclarationSyntax methodDeclaration)
{
if (OnPropertyChanged.IsMatch(method, context.SemanticModel, context.CancellationToken, out var parameter) == AnalysisResult.Yes)
{
if (ShouldBeCallerMemberName(parameter, out var parameterSyntax))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptors.INPC004UseCallerMemberName, parameterSyntax !.GetLocation()));
}
if (ShouldBeProtected() is { } location)
{
context.ReportDiagnostic(
Diagnostic.Create(
Descriptors.INPC018InvokerShouldBeProtected,
location));
}
}
else if (TrySet.IsMatch(method, context.SemanticModel, context.CancellationToken, out _, out _, out parameter) == AnalysisResult.Yes)
{
if (ShouldBeCallerMemberName(parameter, out var parameterSyntax))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptors.INPC004UseCallerMemberName, parameterSyntax !.GetLocation()));
}
if (ShouldBeProtected() is { } location)
{
context.ReportDiagnostic(
Diagnostic.Create(
Descriptors.INPC018InvokerShouldBeProtected,
location));
}
}
}
bool ShouldBeCallerMemberName(IParameterSymbol candidate, out ParameterSyntax?parameterSyntax)
{
parameterSyntax = null;
return(!candidate.IsCallerMemberName() &&
candidate.Type == KnownSymbol.String &&
methodDeclaration.TryFindParameter(candidate.Name, out parameterSyntax) &&
CallerMemberNameAttribute.IsAvailable(context.SemanticModel));
}
Location?ShouldBeProtected()
{
if (method is { DeclaredAccessibility : Accessibility.Private, ContainingType : { IsSealed : false, IsStatic : false } })
protected override async Task RegisterCodeFixesAsync(DocumentEditorCodeFixContext context)
{
var syntaxRoot = await context.Document.GetSyntaxRootAsync(context.CancellationToken)
.ConfigureAwait(false);
var semanticModel = await context.Document.GetSemanticModelAsync(context.CancellationToken)
.ConfigureAwait(false);
foreach (var diagnostic in context.Diagnostics)
{
if (syntaxRoot.TryFindNodeOrAncestor(diagnostic, out PropertyDeclarationSyntax? propertyDeclaration) &&
propertyDeclaration.Parent is ClassDeclarationSyntax classDeclarationSyntax &&
semanticModel.TryGetSymbol(classDeclarationSyntax, context.CancellationToken, out var type))
{
if (TrySet.TryFind(type, semanticModel, context.CancellationToken, out var trySetMethod) &&
TrySet.CanCreateInvocation(trySetMethod, out _))
{
if (Property.IsMutableAutoProperty(propertyDeclaration, out var getter, out var setter))
{
context.RegisterCodeFix(
trySetMethod.DisplaySignature(),
(editor, cancellationToken) => TrySet(editor, cancellationToken),
trySetMethod.MetadataName,
diagnostic);
async Task TrySet(DocumentEditor editor, CancellationToken cancellationToken)
{
var fieldAccess = await editor.AddBackingFieldAsync(propertyDeclaration, cancellationToken)
.ConfigureAwait(false);
var trySet = await editor.TrySetInvocationAsync(trySetMethod, fieldAccess, InpcFactory.Value, propertyDeclaration, cancellationToken)
.ConfigureAwait(false);
_ = editor.ReplaceNode(
getter,
x => x.AsExpressionBody(fieldAccess))
.ReplaceNode(
setter,
x => x.AsExpressionBody(trySet));
if (propertyDeclaration.Initializer != null)
{
editor.ReplaceNode(
propertyDeclaration,
(node, g) => ((PropertyDeclarationSyntax)node).WithoutInitializer());
}
_ = editor.FormatNode(propertyDeclaration);
}
}
else if (IsSimpleAssignmentOnly(propertyDeclaration, out _, out var assignment))
{
context.RegisterCodeFix(
trySetMethod.DisplaySignature(),
async(editor, cancellationToken) =>
{
var trySet = await editor.TrySetInvocationAsync(trySetMethod, assignment.Left, assignment.Right, propertyDeclaration, cancellationToken)
.ConfigureAwait(false);
_ = editor.ReplaceNode(
assignment,
x => trySet);
},
trySetMethod.MetadataName,
diagnostic);
}
}
if (OnPropertyChanged.TryFind(type, semanticModel, context.CancellationToken, out var invoker) &&
invoker.Parameters.TrySingle(out var parameter) &&
parameter.Type.IsEither(KnownSymbol.String, KnownSymbol.PropertyChangedEventArgs))
{
if (Property.IsMutableAutoProperty(propertyDeclaration, out var getter, out var setter) &&
semanticModel.TryGetSymbol(propertyDeclaration, context.CancellationToken, out var property))
{
context.RegisterCodeFix(
NotifyWhenValueChanges,
(editor, cancellationToken) =>
NotifyWhenValueChangesAsync(editor, cancellationToken),
nameof(NotifyWhenValueChangesAsync),
diagnostic);
async Task NotifyWhenValueChangesAsync(DocumentEditor editor, CancellationToken cancellationToken)
{
var backingField = await editor.AddBackingFieldAsync(propertyDeclaration, cancellationToken)
.ConfigureAwait(false);
var onPropertyChanged = await editor.OnPropertyChangedInvocationStatementAsync(invoker, propertyDeclaration, cancellationToken)
.ConfigureAwait(false);
_ = editor.ReplaceNode(
getter,
x => x.AsExpressionBody(backingField)
.WithTrailingLineFeed());
_ = editor.ReplaceNode(
setter,
x => x.AsBlockBody(
InpcFactory.IfReturn(
InpcFactory.Equals(property.Type, InpcFactory.Value, backingField, editor.SemanticModel)),
SyntaxFactory.ExpressionStatement(SyntaxFactory.AssignmentExpression(SyntaxKind.SimpleAssignmentExpression, backingField, InpcFactory.Value)),
onPropertyChanged));
if (propertyDeclaration.Initializer != null)
{
_ = editor.ReplaceNode(
propertyDeclaration,
x => x.WithoutInitializer());
}
_ = editor.FormatNode(propertyDeclaration);
}
}
/// <inheritdoc/>
protected override async Task RegisterCodeFixesAsync(DocumentEditorCodeFixContext context)
{
var syntaxRoot = await context.Document.GetSyntaxRootAsync(context.CancellationToken)
.ConfigureAwait(false);
var semanticModel = await context.Document.GetSemanticModelAsync(context.CancellationToken)
.ConfigureAwait(false);
foreach (var diagnostic in context.Diagnostics)
{
if (diagnostic.Properties.TryGetValue(MutationAnalyzer.PropertyNameKey, out var propertyName))
{
if (syntaxRoot.TryFindNodeOrAncestor(diagnostic, out ExpressionSyntax? expression) &&
expression.TryFirstAncestor(out ClassDeclarationSyntax? classDeclaration) &&
semanticModel.TryGetNamedType(classDeclaration, context.CancellationToken, out var type) &&
OnPropertyChanged.TryFind(type, semanticModel, context.CancellationToken, out var onPropertyChangedMethod) &&
onPropertyChangedMethod.Parameters.TrySingle(out var parameter) &&
parameter.Type.IsEither(KnownSymbol.String, KnownSymbol.PropertyChangedEventArgs))
{
if (expression is InvocationExpressionSyntax trySet &&
semanticModel.TryGetSymbol(trySet, context.CancellationToken, out var trySetMethod) &&
TrySet.IsMatch(trySetMethod, semanticModel, context.CancellationToken) != AnalysisResult.No)
{
switch (trySet.Parent)
{
case ExpressionStatementSyntax expressionStatement:
context.RegisterCodeFix(
$"Notify that property {propertyName} changes.",
async(editor, cancellationToken) =>
{
var onPropertyChangedStatement = await editor.OnPropertyChangedInvocationStatementAsync(onPropertyChangedMethod, propertyName, cancellationToken)
.ConfigureAwait(false);
editor.ReplaceNode(
expressionStatement,
InpcFactory.IfStatement(
trySet,
onPropertyChangedStatement));
if (expressionStatement.TryFirstAncestor(out AccessorDeclarationSyntax? setter))
{
_ = editor.FormatNode(setter);
}
},
nameof(NotifyForDependentPropertyFix),
diagnostic);
break;
case ArrowExpressionClauseSyntax {
Parent: AccessorDeclarationSyntax setter
} :
context.RegisterCodeFix(
$"Notify that property {propertyName} changes.",
async(editor, cancellationToken) =>
{
var onPropertyChangedStatement = await editor.OnPropertyChangedInvocationStatementAsync(onPropertyChangedMethod, propertyName, cancellationToken)
.ConfigureAwait(false);
_ = editor.ReplaceNode(
setter,
x => x.AsBlockBody(
InpcFactory.IfStatement(
trySet,
onPropertyChangedStatement)));
},
nameof(NotifyForDependentPropertyFix),
diagnostic);
break;
