public CompilationContext(Compilation compilation)
{
Compilation = compilation;
var generatorAssembly = GetType().Assembly;
var generatorAssemblyName = generatorAssembly.GetName().Name;
var generatorAssemblyVersion = AttributeExtensions.GetCustomAttribute <System.Reflection.AssemblyInformationalVersionAttribute>(generatorAssembly)?.InformationalVersion ?? string.Empty;
GeneratedCodeAttribute = $"[GeneratedCode(\"{generatorAssemblyName}\", \"{generatorAssemblyVersion}\")]";
GeneratorIgnoreAttribute = compilation.GetTypeByMetadataName(typeof(GeneratorIgnoreAttribute).FullName)
?? throw new Exception("GeneratorIgnoreAttribute symbol not found!");
GeneratorBindingsAttribute = compilation.GetTypeByMetadataName(typeof(GeneratorBindingsAttribute).FullName)
?? throw new Exception("GeneratorBindingsAttribute symbol not found!");
GeneratorMappingAttribute = compilation.GetTypeByMetadataName(typeof(GeneratorMappingAttribute).FullName)
?? throw new Exception("GeneratorMappingAttribute symbol not found!");
}
/// <summary>
/// Generates the source for the overloads based on the defined extension methods.
/// </summary>
/// <param name="context"></param>
/// <param name="collectedExtensionMethods">A dictionary containing the defined extension methods.</param>
/// <param name="generatedPath">The path where to serialize the generated code for debugging.</param>
void GenerateSource(GeneratorExecutionContext context, ImmutableDictionary <string, List <IMethodSymbol> > collectedExtensionMethods, string?generatedPath)
{
// go through all public static types
// the enumerables are defined inside of these
foreach (var containerClass in context.Compilation.SourceModule.GlobalNamespace
.GetAllTypes()
.Where(type =>
type.IsStatic &&
type.IsReferenceType &&
type.IsPublic() &&
!type.ShouldIgnore(context.Compilation)))
{
// cache a GeneratedCodeAttribute string to use on all generated methods
var generatorAssembly = GetType().Assembly;
var generatorAssemblyName = generatorAssembly.GetName().Name;
var generatorAssemblyVersion = AttributeExtensions.GetCustomAttribute <System.Reflection.AssemblyInformationalVersionAttribute>(generatorAssembly)?.InformationalVersion ?? string.Empty;
var generatedCodeAttribute = $"[GeneratedCode(\"{generatorAssemblyName}\", \"{generatorAssemblyVersion}\")]";
// get the inner instance types
// these can be enumerables
foreach (var extendedType in
containerClass.GetTypeMembers()
.OfType <INamedTypeSymbol>()
.Where(type => !(type.IsStatic || type.IsInterface())))
{
// check if it's a value enumerable and keep a reference to the implemented interface
var valueEnumerableInterface = extendedType.GetAllInterfaces()
.FirstOrDefault(@interface => @interface.Name == "IValueEnumerable" || @interface.Name == "IAsyncValueEnumerable");
if (valueEnumerableInterface is null)
{
continue;
}
// get the typed of the enumerable, enumerator and source from the generic parameters declaration
var enumerableType = extendedType;
var enumeratorType = valueEnumerableInterface.TypeArguments[1];
var sourceType = valueEnumerableInterface.TypeArguments[0];
// get the type mappings from the GeneratorMappingsAttribute, if found.
var genericsMapping = ImmutableArray.CreateRange(extendedType.GetGenericMappings(context.Compilation));
// get the name and parameter list of all the instance methods declared in this type
var implementedInstanceMethods = extendedType.GetMembers().OfType <IMethodSymbol>()
.Select(method => Tuple.Create(
method.Name,
ImmutableArray.CreateRange(method.Parameters
.Select(parameter => parameter.Type.ToDisplayString()))));
// get the extension methods for this type declared in the outter static type
var implementedExtensionMethods = containerClass.GetMembers().OfType <IMethodSymbol>()
.Where(method =>
method.IsExtensionMethod &&
method.Parameters[0].Type.ToDisplayString() == extendedType.ToDisplayString())
.Select(method => Tuple.Create(
method.Name,
ImmutableArray.CreateRange(method.Parameters
.Skip(1)
.Select(parameter => parameter.Type.ToDisplayString()))));
// join the two lists together as these are the implemented methods for this type
// the generated methods will be added to this list
var implementedMethods = implementedInstanceMethods.Concat(implementedExtensionMethods)
.ToList();
var instanceMethods = new List <IMethodSymbol>();
var extensionMethods = new List <IMethodSymbol>();
// go through all the implemented interfaces so that
// the overloads are generated based on the extension methods defined for these
var extendedTypeInterfaces = extendedType.AllInterfaces;
for (var interfaceIndex = 0; interfaceIndex < extendedTypeInterfaces.Length; interfaceIndex++)
{
var implementedInterfaceType = extendedTypeInterfaces[interfaceIndex];
// get the extension methods collected for this interface
var key = implementedInterfaceType.OriginalDefinition.MetadataName;
if (!collectedExtensionMethods.TryGetValue(key, out var implementedTypeMethods))
{
continue;
}
// check which ones should be generated
// the method can be already defined by a more performant custom implementation
for (var methodIndex = 0; methodIndex < implementedTypeMethods.Count; methodIndex++)
{
var implementedTypeMethod = implementedTypeMethods[methodIndex];
var methodName = implementedTypeMethod.Name;
var methodParameters = ImmutableArray.CreateRange(implementedTypeMethod.Parameters
.Skip(1)
.Select(parameter => parameter.Type.ToDisplayString(genericsMapping)));
// check if already implemented
if (!implementedMethods.Any(method =>
method.Item1 == methodName &&
method.Item2.SequenceEqual(methodParameters)))
{
// check if there's a collision with a property
if (extendedType.GetMembers().OfType <IPropertySymbol>()
.Any(property => property.Name == methodName))
{
// this method will be generated as an extension method
extensionMethods.Add(implementedTypeMethod);
}
else
{
// this method will generated as an instance method
instanceMethods.Add(implementedTypeMethod);
}
// add to the implemented methods collection
implementedMethods.Add(Tuple.Create(methodName, methodParameters));
}
}
}
// generate the code for the instance methods and extension methods, if any...
if (instanceMethods.Count != 0 || extensionMethods.Count != 0)
{
using var builder = new CodeBuilder();
builder.AppendLine("using System;");
builder.AppendLine("using System.CodeDom.Compiler;");
builder.AppendLine("using System.Diagnostics;");
builder.AppendLine("using System.Runtime.CompilerServices;");
builder.AppendLine();
using (builder.AppendBlock($"namespace NetFabric.Hyperlinq"))
{
// the generator extends the types by adding partial types
// both the outter and the inner types have to be declared as partial
using (builder.AppendBlock($"public static partial class {containerClass.Name}"))
{
// generate the instance methods in the inner type
if (instanceMethods.Count != 0)
{
var extendedTypeGenericParameters = string.Empty;
if (extendedType.IsGenericType)
{
var parametersDefinition = new StringBuilder();
_ = parametersDefinition.Append($"<{extendedType.TypeParameters.Select(parameter => parameter.ToDisplayString()).ToCommaSeparated()}>");
foreach (var typeParameter in extendedType.TypeParameters.Where(typeParameter => typeParameter.ConstraintTypes.Length != 0))
{
_ = parametersDefinition.Append($" where {typeParameter.Name} : {typeParameter.AsConstraintsStrings().ToCommaSeparated()}");
}
extendedTypeGenericParameters = parametersDefinition.ToString();
}
var entity = extendedType.IsValueType
? "readonly partial struct" // it's a value type
: "partial class"; // it's a reference type
using (builder.AppendBlock($"public {entity} {extendedType.Name}{extendedTypeGenericParameters}"))
{
foreach (var instanceMethod in instanceMethods)
{
GenerateInstanceMethod(builder, extendedType, instanceMethod, enumerableType, enumeratorType, generatedCodeAttribute, genericsMapping);
}
}
}
builder.AppendLine();
// generate the extension methods in the outter type
foreach (var extensionMethod in extensionMethods)
{
GenerateExtensionMethod(builder, extendedType, extensionMethod, enumerableType, enumeratorType, generatedCodeAttribute, genericsMapping);
}
}
}
var hitName = $"{containerClass.OriginalDefinition.MetadataName}.{extendedType.OriginalDefinition.MetadataName}.cs";
var source = builder.ToString();
if (generatedPath is object)
{
File.WriteAllText(Path.Combine(generatedPath, hitName), source);
}
hitName = hitName.Replace('`', '.');
context.AddSource(hitName, SourceText.From(source, Encoding.UTF8));
}
}
}
}
