Files
InterfaceGenerator/Speckle.InterfaceGenerator/AutoInterfaceGenerator.cs
T
2024-09-03 09:19:40 +01:00

523 lines
16 KiB
C#

using System;
using System.CodeDom.Compiler;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.Text;
namespace Speckle.InterfaceGenerator;
[Generator]
public class AutoInterfaceGenerator : ISourceGenerator
{
private INamedTypeSymbol? _generateAutoInterfaceAttribute;
private INamedTypeSymbol? _ignoreAttribute;
public void Initialize(GeneratorInitializationContext context)
{
context.RegisterForSyntaxNotifications(() => new SyntaxReceiver());
}
public void Execute(GeneratorExecutionContext context)
{
try
{
ExecuteCore(context);
}
catch (Exception exception)
{
RaiseExceptionDiagnostic(context, exception);
}
}
private static void RaiseExceptionDiagnostic(
GeneratorExecutionContext context,
Exception exception
)
{
var descriptor = new DiagnosticDescriptor(
"Speckle.InterfaceGenerator.CriticalError",
"Exception thrown in InterfaceGenerator",
$"{exception.GetType().FullName} {exception.Message} {exception.StackTrace.Trim()}",
"Speckle.InterfaceGenerator",
DiagnosticSeverity.Error,
true,
customTags: WellKnownDiagnosticTags.AnalyzerException
);
var diagnostic = Diagnostic.Create(descriptor, null);
context.ReportDiagnostic(diagnostic);
}
private void ExecuteCore(GeneratorExecutionContext context)
{
// setting the culture to invariant prevents errors such as emitting a decimal comma (0,1) instead of
// a decimal point (0.1) in certain cultures
var prevCulture = Thread.CurrentThread.CurrentCulture;
Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
GenerateAttributes(context);
GenerateInterfaces(context);
Thread.CurrentThread.CurrentCulture = prevCulture;
}
private static void GenerateAttributes(GeneratorExecutionContext context)
{
context.AddSource(
$"{Attributes.GenerateAutoInterfaceClassname}.g.cs",
SourceText.From(Attributes.AttributesSourceCode, Encoding.UTF8)
);
}
private void GenerateInterfaces(GeneratorExecutionContext context)
{
if (context.SyntaxReceiver is not SyntaxReceiver receiver)
{
return;
}
var compilation = GetCompilation(context);
InitAttributes(compilation);
var classSymbols = GetImplTypeSymbols(compilation, receiver);
List<string> classSymbolNames = [];
foreach (var implTypeSymbol in classSymbols)
{
if (
!implTypeSymbol.TryGetAttribute(
_generateAutoInterfaceAttribute
?? throw new NullReferenceException(
"_generateAutoInterfaceAttribute is null"
),
out var attributes
)
)
{
continue;
}
if (
classSymbolNames.Contains(
implTypeSymbol.GetFullMetadataName(useNameWhenNotFound: true)
)
)
{
continue; // partial class, already added
}
classSymbolNames.Add(implTypeSymbol.GetFullMetadataName(useNameWhenNotFound: true));
var attribute = attributes.Single();
var source = SourceText.From(
GenerateInterfaceCode(implTypeSymbol, attribute),
Encoding.UTF8
);
context.AddSource(
$"{implTypeSymbol.GetFullMetadataName(useNameWhenNotFound: true)}_AutoInterface.g.cs",
source
);
}
}
private static string InferVisibilityModifier(
ISymbol implTypeSymbol,
AttributeData attributeData
)
{
string? result = attributeData.GetNamedParamValue(Attributes.VisibilityModifierPropName);
if (!string.IsNullOrEmpty(result))
{
return result ?? throw new NullReferenceException("result is null");
}
return implTypeSymbol.DeclaredAccessibility switch
{
Accessibility.Public => "public",
_ => "internal",
};
}
private static string InferInterfaceName(ISymbol implTypeSymbol, AttributeData attributeData)
{
return attributeData.GetNamedParamValue(Attributes.InterfaceNamePropName)
?? $"I{implTypeSymbol.Name}";
}
private string GenerateInterfaceCode(
INamedTypeSymbol implTypeSymbol,
AttributeData attributeData
)
{
using var stream = new MemoryStream();
var streamWriter = new StreamWriter(stream, Encoding.UTF8);
var codeWriter = new IndentedTextWriter(streamWriter, " ");
var namespaceName = implTypeSymbol.ContainingNamespace.ToDisplayString();
var interfaceName = InferInterfaceName(implTypeSymbol, attributeData);
var visibilityModifier = InferVisibilityModifier(implTypeSymbol, attributeData);
//https://stackoverflow.com/questions/55492214/the-annotation-for-nullable-reference-types-should-only-be-used-in-code-within-a fix for nullable
codeWriter.WriteLine("#nullable enable");
codeWriter.WriteLine("namespace {0}", namespaceName);
codeWriter.WriteLine("{");
++codeWriter.Indent;
WriteSymbolDocsIfPresent(codeWriter, implTypeSymbol);
codeWriter.Write("{0} partial interface {1}", visibilityModifier, interfaceName);
WriteTypeGenericsIfNeeded(codeWriter, implTypeSymbol);
codeWriter.WriteLine();
codeWriter.WriteLine("{");
++codeWriter.Indent;
GenerateInterfaceMemberDefinitions(codeWriter, implTypeSymbol);
--codeWriter.Indent;
codeWriter.WriteLine("}");
--codeWriter.Indent;
codeWriter.WriteLine("}");
codeWriter.WriteLine("#nullable restore");
codeWriter.Flush();
stream.Seek(0, SeekOrigin.Begin);
using var reader = new StreamReader(stream, Encoding.UTF8, true);
return reader.ReadToEnd();
}
private static void WriteTypeGenericsIfNeeded(
TextWriter writer,
INamedTypeSymbol implTypeSymbol
)
{
if (!implTypeSymbol.IsGenericType)
{
return;
}
writer.Write("<");
writer.WriteJoin(", ", implTypeSymbol.TypeParameters.Select(x => x.Name));
writer.Write(">");
WriteTypeParameterConstraints(writer, implTypeSymbol.TypeParameters);
}
private void GenerateInterfaceMemberDefinitions(
TextWriter writer,
INamedTypeSymbol implTypeSymbol
)
{
foreach (var member in implTypeSymbol.GetMembers())
{
if (
member.DeclaredAccessibility != Accessibility.Public
|| member.HasAttribute(
_ignoreAttribute ?? throw new NullReferenceException("_ignoreAttribute is null")
)
)
{
continue;
}
GenerateInterfaceMemberDefinition(writer, implTypeSymbol, member);
}
}
private static void GenerateInterfaceMemberDefinition(
TextWriter writer,
INamedTypeSymbol owner,
ISymbol member
)
{
switch (member)
{
case IPropertySymbol propertySymbol:
GeneratePropertyDefinition(writer, propertySymbol);
break;
case IMethodSymbol methodSymbol:
GenerateMethodDefinition(writer, owner, methodSymbol);
break;
}
}
private static void WriteSymbolDocsIfPresent(TextWriter writer, ISymbol symbol)
{
var xml = symbol.GetDocumentationCommentXml();
if (string.IsNullOrWhiteSpace(xml))
{
return;
}
// omit the fist and last lines to skip the <member> tag
var reader = new StringReader(xml);
var lines = new List<string>();
while (true)
{
var line = reader.ReadLine();
if (line is null)
{
break;
}
lines.Add(line);
}
for (int i = 1; i < lines.Count - 1; i++)
{
var line = lines[i].TrimStart(); // for some reason, 4 spaces are inserted to the beginning of the line
writer.WriteLine("/// {0}", line);
}
}
private static bool IsPublicOrInternal(ISymbol symbol)
{
return symbol.DeclaredAccessibility is Accessibility.Public or Accessibility.Internal;
}
private static void GeneratePropertyDefinition(
TextWriter writer,
IPropertySymbol propertySymbol
)
{
if (propertySymbol.IsStatic)
{
return;
}
bool hasPublicGetter =
propertySymbol.GetMethod is not null && IsPublicOrInternal(propertySymbol.GetMethod);
bool hasPublicSetter =
propertySymbol.SetMethod is not null && IsPublicOrInternal(propertySymbol.SetMethod);
if (!hasPublicGetter && !hasPublicSetter)
{
return;
}
WriteSymbolDocsIfPresent(writer, propertySymbol);
if (propertySymbol.IsIndexer)
{
writer.Write("{0} this[", propertySymbol.Type.GetNamespaceAndType());
writer.WriteJoin(", ", propertySymbol.Parameters, WriteMethodParam);
writer.Write("] ");
}
else
{
writer.Write("{0} {1} ", propertySymbol.Type, propertySymbol.Name); // ex. int Foo
}
writer.Write("{ ");
if (hasPublicGetter)
{
writer.Write("get; ");
}
if (hasPublicSetter)
{
if (propertySymbol.SetMethod?.IsInitOnly ?? false)
{
writer.Write("init; ");
}
else
{
writer.Write("set; ");
}
}
writer.WriteLine("}");
}
private static void GenerateMethodDefinition(
TextWriter writer,
INamedTypeSymbol owner,
IMethodSymbol methodSymbol
)
{
if (methodSymbol.MethodKind != MethodKind.Ordinary || methodSymbol.IsStatic)
{
return;
}
if (methodSymbol.IsImplicitlyDeclared && methodSymbol.Name != "Deconstruct")
{
// omit methods that are auto generated by the compiler (eg. record's methods),
// except for the record Deconstruct method
return;
}
WriteSymbolDocsIfPresent(writer, methodSymbol);
writer.Write("{0} {1}", methodSymbol.ReturnType.GetNamespaceAndType(), methodSymbol.Name); // ex. int Foo
if (methodSymbol.IsGenericMethod)
{
writer.Write("<");
writer.WriteJoin(
", ",
methodSymbol.TypeParameters.Select(x => x.GetNamespaceAndType())
);
writer.Write(">");
}
writer.Write("(");
writer.WriteJoin(", ", methodSymbol.Parameters, WriteMethodParam);
writer.Write(")");
if (methodSymbol.IsGenericMethod)
{
WriteTypeParameterConstraints(writer, methodSymbol.TypeParameters);
}
writer.WriteLine(";");
}
private static void WriteMethodParam(TextWriter writer, IParameterSymbol param)
{
if (param.IsParams)
{
writer.Write("params ");
}
switch (param.RefKind)
{
case RefKind.Ref:
writer.Write("ref ");
break;
case RefKind.Out:
writer.Write("out ");
break;
case RefKind.In:
writer.Write("in ");
break;
}
writer.Write(param.Type.GetNamespaceAndType());
writer.Write(" ");
if (StringExtensions.IsCSharpKeyword(param.Name))
{
writer.Write("@");
}
writer.Write(param.Name);
if (param.HasExplicitDefaultValue)
{
WriteParamExplicitDefaultValue(writer, param);
}
}
private static void WriteParamExplicitDefaultValue(TextWriter writer, IParameterSymbol param)
{
if (param.ExplicitDefaultValue is null)
{
writer.Write(" = default");
}
else
{
switch (param.Type.Name)
{
case nameof(String):
writer.Write(" = \"{0}\"", param.ExplicitDefaultValue);
break;
case nameof(Single):
writer.Write(" = {0}f", param.ExplicitDefaultValue);
break;
case nameof(Double):
writer.Write(" = {0}d", param.ExplicitDefaultValue);
break;
case nameof(Decimal):
writer.Write(" = {0}m", param.ExplicitDefaultValue);
break;
case nameof(Boolean):
writer.Write(" = {0}", param.ExplicitDefaultValue.ToString().ToLower());
break;
case nameof(Nullable<bool>):
writer.Write(" = {0}", param.ExplicitDefaultValue.ToString().ToLower());
break;
default:
writer.Write(" = {0}", param.ExplicitDefaultValue);
break;
}
}
}
private static void WriteTypeParameterConstraints(
TextWriter writer,
IEnumerable<ITypeParameterSymbol> typeParameters
)
{
foreach (var typeParameter in typeParameters)
{
var constraints = typeParameter.EnumGenericConstraints().ToList();
if (constraints.Count == 0)
{
break;
}
writer.Write(" where {0} : ", typeParameter.Name);
writer.WriteJoin(", ", constraints);
}
}
private void InitAttributes(Compilation compilation)
{
_generateAutoInterfaceAttribute = compilation.GetTypeByMetadataName(
$"{Attributes.AttributesNamespace}.{Attributes.GenerateAutoInterfaceClassname}"
);
_ignoreAttribute = compilation.GetTypeByMetadataName(
$"{Attributes.AttributesNamespace}.{Attributes.AutoInterfaceIgnoreAttributeClassname}"
);
}
private static IEnumerable<INamedTypeSymbol> GetImplTypeSymbols(
Compilation compilation,
SyntaxReceiver receiver
)
{
return receiver
.CandidateTypes.Select(candidate => GetTypeSymbol(compilation, candidate))
.Where(x => x != null)
.Cast<INamedTypeSymbol>();
}
private static INamedTypeSymbol? GetTypeSymbol(Compilation compilation, SyntaxNode type)
{
var model = compilation.GetSemanticModel(type.SyntaxTree);
var typeSymbol = model.GetDeclaredSymbol(type);
return typeSymbol as INamedTypeSymbol;
}
private static Compilation GetCompilation(GeneratorExecutionContext context)
{
var options = context.Compilation.SyntaxTrees.First().Options as CSharpParseOptions;
var compilation = context.Compilation.AddSyntaxTrees(
CSharpSyntaxTree.ParseText(
SourceText.From(Attributes.AttributesSourceCode, Encoding.UTF8),
options
)
);
return compilation;
}
}