Restrict the use of TypelySpecification with an analyser (#37)

Co-authored-by: Adam Paquette <nfs12@gmail.com>

src/Typely.Generators/Analysers/TypelySpecificationAnalyser.cs

@@ -0,0 +1,240 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+using System.Collections.Immutable;
+using Typely.Generators.Infrastructure;
+using Typely.Generators.Typely;
+using Typely.Generators.Typely.Parsing;
+
+namespace Typely.Generators.Analysers;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public class TypelySpecificationAnalyser : DiagnosticAnalyzer
+{
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics { get; } =
+        ImmutableArray.Create(
+            DiagnosticDescriptors.TYP0001_UnsupportedExpression,
+            DiagnosticDescriptors.TYP0002_UnsupportedParameter,
+            DiagnosticDescriptors.TYP0003_UnsupportedMethod,
+            DiagnosticDescriptors.TYP0004_UnsupportedField,
+            DiagnosticDescriptors.TYP0005_UnsupportedProperty,
+            DiagnosticDescriptors.TYP0006_UnsupportedType,
+            DiagnosticDescriptors.TYP0007_UnsupportedVariable);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.EnableConcurrentExecution();
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.Analyze |
+                                               GeneratedCodeAnalysisFlags.ReportDiagnostics);
+        context.RegisterCompilationStartAction(OnCompilationStart);
+    }
+
+    private static void OnCompilationStart(CompilationStartAnalysisContext context)
+    {
+        var typeCache = new TypeCache(context.Compilation);
+        if (typeCache.ITypelySpecification == null)
+        {
+            return;
+        }
+
+        context.RegisterSymbolAction(ctx => AnalyseSymbol(ctx, typeCache),
+            SymbolKind.NamedType);
+
+        context.RegisterSyntaxNodeAction(ctx => AnalyzeSyntaxNode(ctx, typeCache),
+            SyntaxKind.ClassDeclaration);
+    }
+
+    private static void AnalyseSymbol(SymbolAnalysisContext context, TypeCache typeCache)
+    {
+        var namedTypeSymbol = (INamedTypeSymbol)context.Symbol;
+        if (!IsTypelySpecificationClass(namedTypeSymbol, typeCache.ITypelySpecification!))
+        {
+            return;
+        }
+
+        foreach (var member in namedTypeSymbol.GetMembers())
+        {
+            switch (member)
+            {
+                case IFieldSymbol symbol:
+                    AnalyseFieldSymbol(context, symbol);
+                    break;
+                case IMethodSymbol symbol:
+                    AnalyseMethodSymbol(context, symbol);
+                    break;
+                case INamedTypeSymbol symbol:
+                    AnalyseNamedTypeSymbol(context, symbol);
+                    break;
+                case IPropertySymbol symbol:
+                    AnalysePropertySymbol(context, symbol);
+                    break;
+            }
+        }
+    }
+
+    private static void AnalysePropertySymbol(SymbolAnalysisContext context, IPropertySymbol property)
+    {
+        context.ReportDiagnostic(Diagnostic.Create(
+            DiagnosticDescriptors.TYP0005_UnsupportedProperty,
+            property.Locations.FirstOrDefault(),
+            property.Name));
+    }
+
+    private static void AnalyseNamedTypeSymbol(SymbolAnalysisContext context, INamedTypeSymbol namedType)
+    {
+        context.ReportDiagnostic(Diagnostic.Create(
+            DiagnosticDescriptors.TYP0006_UnsupportedType,
+            namedType.Locations.FirstOrDefault(),
+            namedType.Name));
+    }
+
+    private static void AnalyseMethodSymbol(SymbolAnalysisContext context, IMethodSymbol method)
+    {
+        if (!IsAllowedMethod(method))
+        {
+            context.ReportDiagnostic(Diagnostic.Create(
+                DiagnosticDescriptors.TYP0003_UnsupportedMethod,
+                method.Locations.FirstOrDefault(),
+                method.Name));
+        }
+
+        bool IsAllowedMethod(IMethodSymbol method) =>
+            method.MethodKind is MethodKind.Constructor or MethodKind.PropertyGet or MethodKind.PropertySet ||
+            IsCreateMethod();
+
+        bool IsCreateMethod() =>
+            method is { MethodKind: MethodKind.Ordinary, Name: SymbolNames.CreateMethod };
+    }
+
+    private static void AnalyseFieldSymbol(SymbolAnalysisContext context, IFieldSymbol field)
+    {
+        context.ReportDiagnostic(Diagnostic.Create(
+            DiagnosticDescriptors.TYP0004_UnsupportedField,
+            field.Locations.FirstOrDefault(),
+            field.Name));
+    }
+
+    private static void AnalyzeSyntaxNode(SyntaxNodeAnalysisContext context, TypeCache typeCache)
+    {
+        var classDeclaration = (ClassDeclarationSyntax)context.Node;
+
+        if (!Parser.IsTypelySpecificationClass(classDeclaration))
+        {
+            return;
+        }
+
+        var createMethodDeclaration = classDeclaration.DescendantNodes()
+            .OfType<MethodDeclarationSyntax>()
+            .FirstOrDefault(x => x.Identifier.Text == SymbolNames.CreateMethod);
+
+        if (createMethodDeclaration is null)
+        {
+            return;
+        }
+
+        var localDeclarations = createMethodDeclaration.DescendantNodes().OfType<LocalDeclarationStatementSyntax>();
+        var semanticModel = context.SemanticModel;
+
+        foreach (var localDeclaration in localDeclarations)
+        {
+            foreach (var variable in localDeclaration.Declaration.Variables)
+            {
+                if (semanticModel.GetDeclaredSymbol(variable) is not ILocalSymbol localSymbol)
+                {
+                    continue;
+                }
+
+                if (!typeCache.SupportedVariablesTypes.Contains(localSymbol.Type, SymbolEqualityComparer.Default))
+                {
+                    context.ReportDiagnostic(Diagnostic.Create(
+                        DiagnosticDescriptors.TYP0007_UnsupportedVariable,
+                        localSymbol.Locations.FirstOrDefault(),
+                        localSymbol.Type,
+                        localSymbol.Name));
+                }
+            }
+        }
+    }
+
+    private static bool IsTypelySpecificationClass(INamedTypeSymbol type, INamedTypeSymbol itypelySpecification)
+    {
+        return type.TypeKind == TypeKind.Class &&
+               !type.IsStatic &&
+               type.Implements(itypelySpecification);
+    }
+
+    private sealed class TypeCache
+    {
+        public TypeCache(Compilation compilation)
+        {
+            ITypelySpecification = compilation.GetTypeByMetadataName(SymbolNames.ITypelySpecification);
+            SupportedVariablesTypes = new[]
+            {
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfBool),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfByte),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfChar),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfDateOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfDateTime),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfDateTimeOffset),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfInt),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfDecimal),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfFloat),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfGuid),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfDouble),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfLong),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfSByte),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfShort),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfString),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfTimeOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfTimeSpan),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfUInt),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfULong),
+                compilation.GetTypeByMetadataName(SymbolNames.ITypelyBuilderOfUShort),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfBool),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfByte),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfChar),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfDateOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfDateTime),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfDateTimeOffset),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfInt),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfDecimal),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfFloat),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfGuid),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfDouble),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfLong),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfSByte),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfShort),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfString),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfTimeOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfTimeSpan),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfUInt),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfULong),
+                compilation.GetTypeByMetadataName(SymbolNames.IRuleBuilderOfUShort),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfBool),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfByte),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfChar),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfDateOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfDateTime),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfDateTimeOffset),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfInt),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfDecimal),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfFloat),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfGuid),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfDouble),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfLong),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfSByte),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfShort),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfString),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfTimeOnly),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfTimeSpan),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfUInt),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfULong),
+                compilation.GetTypeByMetadataName(SymbolNames.IFactoryOfUShort)
+            };
+        }
+
+        public INamedTypeSymbol? ITypelySpecification { get; }
+        public INamedTypeSymbol?[] SupportedVariablesTypes { get; }
+    }
+}

src/Typely.Generators/Infrastructure/SymbolExtensions.cs

@@ -0,0 +1,18 @@
+using Microsoft.CodeAnalysis;
+
+namespace Typely.Generators.Infrastructure;
+
+public static class SymbolExtensions
+{
+    public static bool Implements(this ITypeSymbol type, ITypeSymbol interfaceType)
+    {
+        foreach (var t in type.AllInterfaces)
+        {
+            if (SymbolEqualityComparer.Default.Equals(t, interfaceType))
+            {
+                return true;
+            }
+        }
+        return false;
+    }
+}

src/Typely.Generators/Typely.Generators.csproj

@@ -46,8 +46,4 @@
             <DependentUpon>Emitter.cs</DependentUpon>
         </Compile>
     </ItemGroup>
-
-    <ItemGroup>
-        <AdditionalFiles Include="AnalyzerReleases.Unshipped.md" />
-    </ItemGroup>
 </Project>

src/Typely.Generators/Typely/DiagnosticDescriptors.cs

@@ -1,21 +1,64 @@
 using Microsoft.CodeAnalysis;
 
+// ReSharper disable InconsistentNaming
+
 namespace Typely.Generators.Typely;
 
 public static class DiagnosticDescriptors
 {
-    public static DiagnosticDescriptor UnsupportedExpression { get; } = new(
+    public static DiagnosticDescriptor TYP0001_UnsupportedExpression { get; } = new(
         id: "TYP0001",
         title: "Unsupported expression",
-        messageFormat: "The use of '{0}' is not allowed in a TypelySpecification.",
+        messageFormat: "The use of '{0}' is not supported in a TypelySpecification.",
         category: "Design",
         defaultSeverity: DiagnosticSeverity.Error,
         isEnabledByDefault: true);
-    
-    public static DiagnosticDescriptor UnsupportedParameter { get; } = new(
+
+    public static DiagnosticDescriptor TYP0002_UnsupportedParameter { get; } = new(
         id: "TYP0002",
         title: "Unsupported parameter",
-        messageFormat: "'{0}' is not allowed as a parameter of '{1}' in the TypelySpecification. Instead use a string constant.",
+        messageFormat:
+        "'{0}' is not supported as a parameter of '{1}' in the TypelySpecification. Instead use a string constant.",
+        category: "Design",
+        defaultSeverity: DiagnosticSeverity.Error,
+        isEnabledByDefault: true);
+
+    public static DiagnosticDescriptor TYP0003_UnsupportedMethod { get; } = new(
+        id: "TYP0003",
+        title: "Unsupported method",
+        messageFormat: "Custom methods are not supported in a TypelySpecification. Remove '{0}'.",
+        category: "Design",
+        defaultSeverity: DiagnosticSeverity.Error,
+        isEnabledByDefault: true);
+
+    public static DiagnosticDescriptor TYP0004_UnsupportedField { get; } = new(
+        id: "TYP0004",
+        title: "Unsupported field",
+        messageFormat: "Custom fields are not supported in a TypelySpecification. Remove '{0}'.",
+        category: "Design",
+        defaultSeverity: DiagnosticSeverity.Error,
+        isEnabledByDefault: true);
+
+    public static DiagnosticDescriptor TYP0005_UnsupportedProperty { get; } = new(
+        id: "TYP0005",
+        title: "Unsupported property",
+        messageFormat: "Custom properties are not supported in a TypelySpecification. Remove '{0}'.",
+        category: "Design",
+        defaultSeverity: DiagnosticSeverity.Error,
+        isEnabledByDefault: true);
+
+    public static DiagnosticDescriptor TYP0006_UnsupportedType { get; } = new(
+        id: "TYP0006",
+        title: "Unsupported type",
+        messageFormat: "Custom types are not supported in a TypelySpecification. Remove '{0}'.",
+        category: "Design",
+        defaultSeverity: DiagnosticSeverity.Error,
+        isEnabledByDefault: true);
+
+    public static DiagnosticDescriptor TYP0007_UnsupportedVariable { get; } = new(
+        id: "TYP0007",
+        title: "Unsupported variable",
+        messageFormat: "Variable type '{0}' is not supported for '{1}' in a TypelySpecification.",
         category: "Design",
         defaultSeverity: DiagnosticSeverity.Error,
         isEnabledByDefault: true);