// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using Analyzer.Utilities;
using Analyzer.Utilities.Extensions;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.Diagnostics;
namespace Microsoft.CodeQuality.Analyzers.ApiDesignGuidelines
{
using static MicrosoftCodeQualityAnalyzersResources;
/// <summary>
/// CA1019: <inheritdoc cref="DefineAccessorsForAttributeArgumentsTitle"/>
///
/// Cause:
/// In its constructor, an attribute defines arguments that do not have corresponding properties.
/// </summary>
[DiagnosticAnalyzer(LanguageNames.CSharp, LanguageNames.VisualBasic)]
public sealed class DefineAccessorsForAttributeArgumentsAnalyzer : DiagnosticAnalyzer
{
internal const string RuleId = "CA1019";
internal const string AddAccessorCase = "AddAccessor";
internal const string MakePublicCase = "MakePublic";
internal const string RemoveSetterCase = "RemoveSetter";
private static readonly LocalizableString s_localizableTitle = CreateLocalizableResourceString(nameof(DefineAccessorsForAttributeArgumentsTitle));
internal static readonly DiagnosticDescriptor DefaultRule = DiagnosticDescriptorHelper.Create(
RuleId,
s_localizableTitle,
CreateLocalizableResourceString(nameof(DefineAccessorsForAttributeArgumentsMessageDefault)),
DiagnosticCategory.Design,
RuleLevel.Disabled,
description: null,
isPortedFxCopRule: true,
isDataflowRule: false);
internal static readonly DiagnosticDescriptor IncreaseVisibilityRule = DiagnosticDescriptorHelper.Create(
RuleId,
s_localizableTitle,
CreateLocalizableResourceString(nameof(DefineAccessorsForAttributeArgumentsMessageIncreaseVisibility)),
DiagnosticCategory.Design,
RuleLevel.Disabled,
description: null,
isPortedFxCopRule: true,
isDataflowRule: false);
internal static readonly DiagnosticDescriptor RemoveSetterRule = DiagnosticDescriptorHelper.Create(
RuleId,
s_localizableTitle,
CreateLocalizableResourceString(nameof(DefineAccessorsForAttributeArgumentsMessageRemoveSetter)),
DiagnosticCategory.Design,
RuleLevel.Disabled,
description: null,
isPortedFxCopRule: true,
isDataflowRule: false);
public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics { get; } = ImmutableArray.Create(DefaultRule, IncreaseVisibilityRule, RemoveSetterRule);
public override void Initialize(AnalysisContext context)
{
context.EnableConcurrentExecution();
context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
context.RegisterCompilationStartAction(compilationContext =>
{
INamedTypeSymbol? attributeType = compilationContext.Compilation.GetOrCreateTypeByMetadataName(WellKnownTypeNames.SystemAttribute);
if (attributeType == null)
{
return;
}
compilationContext.RegisterSymbolAction(context =>
{
AnalyzeSymbol((INamedTypeSymbol)context.Symbol, attributeType, context.Compilation, context.ReportDiagnostic);
},
SymbolKind.NamedType);
});
}
private static void AnalyzeSymbol(INamedTypeSymbol symbol, INamedTypeSymbol attributeType, Compilation compilation, Action<Diagnostic> addDiagnostic)
{
if (symbol != null && symbol.GetBaseTypesAndThis().Contains(attributeType) && symbol.DeclaredAccessibility != Accessibility.Private)
{
IEnumerable<IParameterSymbol> parametersToCheck = GetAllPublicConstructorParameters(symbol);
if (parametersToCheck.Any())
{
IDictionary<string, IPropertySymbol> propertiesMap = GetAllPropertiesInTypeChain(symbol);
AnalyzeParameters(compilation, parametersToCheck, propertiesMap, symbol, addDiagnostic);
}
}
}
private static IEnumerable<IParameterSymbol> GetAllPublicConstructorParameters(INamedTypeSymbol attributeType)
{
// FxCop compatibility:
// Only examine parameters of public constructors. Can't use protected
// constructors to define an attribute so this rule only applies to
// public constructors.
IEnumerable<IMethodSymbol> instanceConstructorsToCheck = attributeType.InstanceConstructors.Where(c => c.DeclaredAccessibility == Accessibility.Public);
if (instanceConstructorsToCheck.Any())
{
var uniqueParamNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
foreach (IMethodSymbol constructor in instanceConstructorsToCheck)
{
foreach (IParameterSymbol parameter in constructor.Parameters)
{
if (uniqueParamNames.Add(parameter.Name))
{
yield return parameter;
}
}
}
}
}
private static IDictionary<string, IPropertySymbol> GetAllPropertiesInTypeChain(INamedTypeSymbol attributeType)
{
var propertiesMap = new Dictionary<string, IPropertySymbol>(StringComparer.OrdinalIgnoreCase);
foreach (INamedTypeSymbol currentType in attributeType.GetBaseTypesAndThis())
{
foreach (IPropertySymbol property in currentType.GetMembers().Where(m => m.Kind == SymbolKind.Property).Cast<IPropertySymbol>())
{
if (!propertiesMap.ContainsKey(property.Name))
{
propertiesMap.Add(property.Name, property);
}
}
}
return propertiesMap;
}
private static void AnalyzeParameters(Compilation compilation, IEnumerable<IParameterSymbol> parameters, IDictionary<string, IPropertySymbol> propertiesMap, INamedTypeSymbol attributeType, Action<Diagnostic> addDiagnostic)
{
foreach (IParameterSymbol parameter in parameters)
{
if (parameter.Type.Kind != SymbolKind.ErrorType)
{
if (!propertiesMap.TryGetValue(parameter.Name, out IPropertySymbol property) ||
!parameter.Type.IsAssignableTo(property.Type, compilation))
{
// Add a public read-only property accessor for positional argument '{0}' of attribute '{1}'.
addDiagnostic(GetDefaultDiagnostic(parameter, attributeType));
}
else
{
if (property.GetMethod == null)
{
// Add a public read-only property accessor for positional argument '{0}' of attribute '{1}'.
addDiagnostic(GetDefaultDiagnostic(parameter, attributeType));
}
else if (property.DeclaredAccessibility != Accessibility.Public ||
property.GetMethod.DeclaredAccessibility != Accessibility.Public)
{
if (!property.ContainingType.Equals(attributeType))
{
// A non-public getter exists in one of the base types.
// However, we cannot be sure if the user can modify the base type (it could be from a third party library).
// So generate the default diagnostic instead of increase visibility here.
// Add a public read-only property accessor for positional argument '{0}' of attribute '{1}'.
addDiagnostic(GetDefaultDiagnostic(parameter, attributeType));
}
else
{
// If '{0}' is the property accessor for positional argument '{1}', make it public.
addDiagnostic(GetIncreaseVisibilityDiagnostic(parameter, property));
}
}
if (property.SetMethod != null &&
property.SetMethod.DeclaredAccessibility == Accessibility.Public &&
Equals(property.ContainingType, attributeType))
{
// Remove the property setter from '{0}' or reduce its accessibility because it corresponds to positional argument '{1}'.
addDiagnostic(GetRemoveSetterDiagnostic(parameter, property));
}
}
}
}
}
private static Diagnostic GetDefaultDiagnostic(IParameterSymbol parameter, INamedTypeSymbol attributeType)
{
// Add a public read-only property accessor for positional argument '{0}' of attribute '{1}'.
return parameter.Locations.CreateDiagnostic(DefaultRule, new Dictionary<string, string?> { { "case", AddAccessorCase } }.ToImmutableDictionary(), parameter.Name, attributeType.Name);
}
private static Diagnostic GetIncreaseVisibilityDiagnostic(IParameterSymbol parameter, IPropertySymbol property)
{
// If '{0}' is the property accessor for positional argument '{1}', make it public.
return property.GetMethod!.Locations.CreateDiagnostic(IncreaseVisibilityRule, new Dictionary<string, string?> { { "case", MakePublicCase } }.ToImmutableDictionary(), property.Name, parameter.Name);
}
private static Diagnostic GetRemoveSetterDiagnostic(IParameterSymbol parameter, IPropertySymbol property)
{
// Remove the property setter from '{0}' or reduce its accessibility because it corresponds to positional argument '{1}'.
return property.SetMethod!.Locations.CreateDiagnostic(RemoveSetterRule, new Dictionary<string, string?> { { "case", RemoveSetterCase } }.ToImmutableDictionary(), property.Name, parameter.Name);
}
}
}