public sealed override void Initialize(AnalysisContext context)
{
context.RegisterCompilationStartAction(
(compilationContext) =>
{
HashSet <IFieldSymbol> assignedToFields = new HashSet <IFieldSymbol>();
HashSet <IFieldSymbol> mightBecomeReadOnlyFields = new HashSet <IFieldSymbol>();
compilationContext.RegisterOperationBlockStartAction(
(operationBlockContext) =>
{
if (operationBlockContext.OwningSymbol is IMethodSymbol containingMethod)
{
bool inConstructor = containingMethod.MethodKind == MethodKind.Constructor;
ITypeSymbol staticConstructorType = containingMethod.MethodKind == MethodKind.StaticConstructor ? containingMethod.ContainingType : null;
operationBlockContext.RegisterOperationAction(
(operationContext) =>
{
if (operationContext.Operation is IAssignmentOperation assignment)
{
AssignTo(assignment.Target, inConstructor, staticConstructorType, assignedToFields, mightBecomeReadOnlyFields);
}
else if (operationContext.Operation is IIncrementOrDecrementOperation increment)
{
AssignTo(increment.Target, inConstructor, staticConstructorType, assignedToFields, mightBecomeReadOnlyFields);
}
else
{
throw TestExceptionUtilities.UnexpectedValue(operationContext.Operation);
}
},
OperationKind.SimpleAssignment,
OperationKind.CompoundAssignment,
OperationKind.Increment,
OperationKind.Decrement);
operationBlockContext.RegisterOperationAction(
(operationContext) =>
{
IInvocationOperation invocation = (IInvocationOperation)operationContext.Operation;
foreach (IArgumentOperation argument in invocation.Arguments)
{
if (argument.Parameter.RefKind == RefKind.Out || argument.Parameter.RefKind == RefKind.Ref)
{
AssignTo(argument.Value, inConstructor, staticConstructorType, assignedToFields, mightBecomeReadOnlyFields);
}
}
},
OperationKind.Invocation);
}
});
compilationContext.RegisterSymbolAction(
(symbolContext) =>
{
IFieldSymbol field = (IFieldSymbol)symbolContext.Symbol;
if (!field.IsConst && !field.IsReadOnly && !assignedToFields.Contains(field))
{
mightBecomeReadOnlyFields.Add(field);
}
},
SymbolKind.Field
);
compilationContext.RegisterCompilationEndAction(
(compilationEndContext) =>
{
foreach (IFieldSymbol couldBeReadOnlyField in mightBecomeReadOnlyFields)
{
Report(compilationEndContext, couldBeReadOnlyField, FieldCouldBeReadOnlyDescriptor);
}
});
});
}
public sealed override void Initialize(AnalysisContext context)
{
context.RegisterCompilationStartAction(
(compilationContext) =>
{
Dictionary <IFieldSymbol, HashSet <INamedTypeSymbol> > fieldsSourceTypes = new Dictionary <IFieldSymbol, HashSet <INamedTypeSymbol> >();
compilationContext.RegisterOperationBlockStartAction(
(operationBlockContext) =>
{
if (operationBlockContext.OwningSymbol is IMethodSymbol containingMethod)
{
Dictionary <ILocalSymbol, HashSet <INamedTypeSymbol> > localsSourceTypes = new Dictionary <ILocalSymbol, HashSet <INamedTypeSymbol> >();
// Track explicit assignments.
operationBlockContext.RegisterOperationAction(
(operationContext) =>
{
if (operationContext.Operation is IAssignmentOperation assignment)
{
AssignTo(assignment.Target, localsSourceTypes, fieldsSourceTypes, assignment.Value);
}
else if (operationContext.Operation is IIncrementOrDecrementOperation increment)
{
SyntaxNode syntax = increment.Syntax;
ITypeSymbol type = increment.Type;
Optional <object> constantValue = new Optional <object>(1);
bool isImplicit = increment.IsImplicit;
var value = new LiteralExpression(operationContext.Compilation.GetSemanticModel(syntax.SyntaxTree), syntax, type, constantValue, isImplicit);
AssignTo(increment.Target, localsSourceTypes, fieldsSourceTypes, value);
}
else
{
throw TestExceptionUtilities.UnexpectedValue(operationContext.Operation);
}
},
OperationKind.SimpleAssignment,
OperationKind.CompoundAssignment,
OperationKind.Increment);
// Track arguments that match out or ref parameters.
operationBlockContext.RegisterOperationAction(
(operationContext) =>
{
IInvocationOperation invocation = (IInvocationOperation)operationContext.Operation;
foreach (IArgumentOperation argument in invocation.Arguments)
{
if (argument.Parameter.RefKind == RefKind.Out || argument.Parameter.RefKind == RefKind.Ref)
{
AssignTo(argument.Value, localsSourceTypes, fieldsSourceTypes, argument.Parameter.Type);
}
}
},
OperationKind.Invocation);
// Track local variable initializations.
operationBlockContext.RegisterOperationAction(
(operationContext) =>
{
IVariableInitializerOperation initializer = (IVariableInitializerOperation)operationContext.Operation;
if (initializer.Parent is IVariableDeclarationOperation variableDeclaration)
{
foreach (ILocalSymbol local in variableDeclaration.Variables)
{
AssignTo(local, local.Type, localsSourceTypes, initializer.Value);
}
}
},
OperationKind.VariableInitializer);
// Report locals that could have more specific types.
operationBlockContext.RegisterOperationBlockEndAction(
(operationBlockEndContext) =>
{
foreach (ILocalSymbol local in localsSourceTypes.Keys)
{
if (HasMoreSpecificSourceType(local, local.Type, localsSourceTypes, out var mostSpecificSourceType))
{
Report(operationBlockEndContext, local, mostSpecificSourceType, LocalCouldHaveMoreSpecificTypeDescriptor);
}
}
});
}
});
// Track field initializations.
compilationContext.RegisterOperationAction(
(operationContext) =>
{
IFieldInitializerOperation initializer = (IFieldInitializerOperation)operationContext.Operation;
foreach (IFieldSymbol initializedField in initializer.InitializedFields)
{
AssignTo(initializedField, initializedField.Type, fieldsSourceTypes, initializer.Value);
}
},
OperationKind.FieldInitializer);
// Report fields that could have more specific types.
compilationContext.RegisterCompilationEndAction(
(compilationEndContext) =>
{
foreach (IFieldSymbol field in fieldsSourceTypes.Keys)
{
if (HasMoreSpecificSourceType(field, field.Type, fieldsSourceTypes, out var mostSpecificSourceType))
{
Report(compilationEndContext, field, mostSpecificSourceType, FieldCouldHaveMoreSpecificTypeDescriptor);
}
}
});
});
}
