#88 Support for contextual/scoped dependency overrides

Author: NikolayPianikov

samples/Clock/ViewModels/ClockViewModel.cs

@@ -5,7 +5,6 @@
 // ReSharper disable once ClassNeverInstantiated.Global
 class ClockViewModel : ViewModel, IClockViewModel, IDisposable, IObserver<Tick>
 {
-
     public ClockViewModel(
         ILog<ClockViewModel> log,
         IClock clock,

samples/Clock/ViewModels/ViewModel.cs

@@ -5,10 +5,10 @@
 abstract class ViewModel
     : INotifyPropertyChanged
 {
-
     public required IDispatcher Dispatcher { private get; init; }
 
     public required ILog<ViewModel> Log { private get; init; }
+
     public event PropertyChangedEventHandler? PropertyChanged;
 
     protected void OnPropertyChanged([CallerMemberName] string? propertyName = null)

samples/WinFormsAppNetCore/FormMain.cs

@@ -5,7 +5,6 @@
 
 partial class FormMain : Form
 {
-
     internal FormMain(IClockViewModel clockViewModel)
     {
         _clockViewModel = clockViewModel;

src/Pure.DI.Core/Components/Api.g.cs

@@ -2994,8 +2994,6 @@ internal interface IContext
         ///         var service = new Service();
         ///         // Initialize an instance with all necessary dependencies
         ///         ctx.BuildUp(service);
-        ///
-        /// 
         ///         return service;
         ///     })
         /// </code>
@@ -3006,7 +3004,7 @@ internal interface IContext
         /// <seealso cref="IBinding.To{T}(System.Func{Pure.DI.IContext,T})"/>
         void BuildUp<T>(T value);
 
-        void Override<T>(T value, object tag = null);
+        void Override<T>(T value, params object[] tags);
     }
 
     /// <summary>

src/Pure.DI.Core/Core/ApiInvocationProcessor.cs

@@ -23,6 +23,7 @@ sealed class ApiInvocationProcessor(
     : IApiInvocationProcessor
 {
     private static readonly char[] TypeNamePartsSeparators = ['.'];
+    private static object NullTag = new object();
 
     public void ProcessInvocation(
         IMetadataVisitor metadataVisitor,
@@ -817,12 +818,12 @@ private MdOverride CreateOverride(
         ref bool hasContextTag)
     {
         var invocation = @override.Expression;
-        if (invocation.ArgumentList.Arguments is not { Count: 1 or 2 })
+        if (invocation.ArgumentList.Arguments.Count == 0)
         {
             return default;
         }
 
-        var args = arguments.GetArgs(invocation.ArgumentList, "value", "tag");
+        var args = arguments.GetArgs(invocation.ArgumentList, "value", "tags");
         if (args[0] is not {} valueArg)
         {
             return default;
@@ -834,19 +835,22 @@ private MdOverride CreateOverride(
             return default;
         }
 
-        var tag = args[1]?.Expression;
-        var hasCtx = HasContextTag(tag, contextParameter);
-        hasContextTag |= hasCtx;
-        var tagValue = hasCtx ? MdTag.ContextTag : tag is null ? null : semantic.GetConstantValue<object>(semanticModel, tag);
-        var resolverTag = new MdTag(0, tagValue);
+        var tagArguments = invocation.ArgumentList.Arguments.Skip(1).ToList();
+        var hasCtx = tagArguments.Aggregate(false, (current, tag) => current | HasContextTag(tag.Expression, contextParameter));
+        var tags = BuildTags(semanticModel, tagArguments)
+            .AsEnumerable()
+            .Select(tag => tag with { Value = tag.Value ?? (hasCtx ? MdTag.ContextTag : null) })
+            .DefaultIfEmpty(new MdTag(0, hasCtx ? MdTag.ContextTag : null))
+            .ToImmutableArray();
+
         var valueExpression = (ExpressionSyntax)localVariableRenamingRewriter.Rewrite(semanticModel, false, true, valueArg.Expression);
         return new MdOverride(
             semanticModel,
             invocation,
-            overrideIdProvider.GetId(argType, tagValue),
+            overrideIdProvider.GetId(argType, tags.Select(tag => tag.Value ?? NullTag).ToImmutableHashSet()),
             @override.Position,
             argType,
-            resolverTag,
+            tags,
             valueExpression);
     }
 

src/Pure.DI.Core/Core/ArgDependencyNodeBuilder.cs

@@ -13,7 +13,7 @@ public IEnumerable<DependencyNode> Build(DependencyNodeBuildContext ctx)
                 continue;
             }
 
-            yield return new DependencyNode(0, binding, Arg: new DpArg(arg, binding));
+            yield return new DependencyNode(0, binding, ctx.TypeConstructor, Arg: new DpArg(arg, binding));
         }
     }
 }

src/Pure.DI.Core/Core/Code/BlockCodeBuilder.cs

@@ -72,11 +72,7 @@ public void Build(BuildContext ctx, in Block block)
             var content = new LinesBuilder();
             foreach (var statement in block.Statements)
             {
-                var curVar = statement.Current;
-                if (ctx.IsFactory || curVar.Injection.Kind != InjectionKind.FactoryInjection || curVar.Node.Lifetime != Lifetime.Transient)
-                {
-                    ctx.StatementBuilder.Build(ctx with { Variable = curVar, Code = content, IsFactory = false }, statement);
-                }
+                ctx.StatementBuilder.Build(ctx with { Variable = statement.Current, Code = content }, statement);
             }
 
             if (content.Count == 0)
@@ -141,7 +137,8 @@ public void Build(BuildContext ctx, in Block block)
             {
                 if (block.Parent is not null
                     && info is { PerBlockRefCount: > 1 }
-                    && code.Count > 11)
+                    && code.Count > 11
+                    && block.Statements.All(i => !i.Current.Info.HasLocalMethod))
                 {
                     var localMethodCode = ctx.LocalFunctionsCode;
                     if (compilations.GetLanguageVersion(compilation) >= LanguageVersion.CSharp9)

src/Pure.DI.Core/Core/Code/CompositionBuilder.cs

@@ -41,7 +41,9 @@ public CompositionCode Build(DependencyGraph graph)
             foreach (var perResolveVar in map.GetPerResolves())
             {
                 ctx.Code.AppendLine($"var {perResolveVar.VariableName} = default({typeResolver.Resolve(graph.Source, perResolveVar.InstanceType)});");
-                if (perResolveVar.Info.RefCount > 0 && perResolveVar.InstanceType.IsValueType)
+                if (perResolveVar.Info.RefCount > 0
+                    && perResolveVar.InstanceType.IsValueType
+                    && perResolveVar.Node.Construct is not { Source.Kind: MdConstructKind.Override })
                 {
                     ctx.Code.AppendLine($"var {perResolveVar.VariableName}Created = false;");
                 }

src/Pure.DI.Core/Core/Code/CompositionClassBuilder.cs

@@ -22,9 +22,9 @@ public CompositionCode Build(CompositionCode composition)
         if (composition.Compilation.Options.NullableContextOptions != NullableContextOptions.Disable)
         {
             code.AppendLine("#nullable enable annotations");
-            code.AppendLine("#pragma warning disable CS0219");
         }
 
+        code.AppendLine("#pragma warning disable CS0219");
         code.AppendLine();
         composition = usingDeclarations.Build(composition);
 

src/Pure.DI.Core/Core/Code/FactoryCodeBuilder.cs

@@ -101,7 +101,7 @@ public void Build(BuildContext ctx, in DpFactory factory)
                                 var argType = typeConstructor.ConstructReversed(typeArg);
                                 if (binding.TypeConstructor is {} bindingTypeConstructor)
                                 {
-                                    argType = bindingTypeConstructor.Construct(setup, binding.SemanticModel.Compilation, argType);
+                                    argType = bindingTypeConstructor.Construct(setup, argType);
                                 }
 
                                 var typeName = symbolNames.GetGlobalName(argType);
@@ -224,14 +224,16 @@ public void Build(BuildContext ctx, in DpFactory factory)
             .GetEnumerator();
 
         var initializationArgsEnum = initializationArgs.Select(i => i.Current).GetEnumerator();
+        ctx = ctx with { LockIsRequired = lockIsRequired, Level = level };
         var injectionsCtx = ctx;
         if (variable.IsLazy && variable.Node.Accumulators.Count > 0)
         {
             injectionsCtx = injectionsCtx with
             {
-                Accumulators = injectionsCtx.Accumulators.AddRange(
-                    variable.Node.Accumulators
-                        .Select(accumulator => accumulator with { IsDeclared = false }))
+                Accumulators = injectionsCtx.Accumulators
+                    .AsEnumerable()
+                    .Select(i => i with { IsDeclared = i.IsRoot && i.IsDeclared })
+                    .ToImmutableArray()
             };
         }
 
@@ -272,7 +274,12 @@ public void Build(BuildContext ctx, in DpFactory factory)
                         code.AppendLine($"{variableNameProvider.GetOverrideVariableName(@override.Source)} = {@override.Source.ValueExpression};");
                     }
 
-                    ctx.StatementBuilder.Build(injectionsCtx with { Level = level, Variable = argument.Current, LockIsRequired = lockIsRequired, IsFactory = true }, argument);
+                    foreach (var argStatement in GetArgsStatements(argument))
+                    {
+                        ctx.StatementBuilder.Build(ctx with { Variable = argStatement.Current }, argStatement);
+                    }
+
+                    ctx.StatementBuilder.Build(injectionsCtx with { Variable = argument.Current }, argument);
                     code.AppendLine($"{(injection.DeclarationRequired ? $"{typeResolver.Resolve(ctx.DependencyGraph.Source, argument.Current.Injection.Type)} " : "")}{injection.VariableName} = {ctx.BuildTools.OnInjected(ctx, argument.Current)};");
                 }
 
@@ -287,6 +294,12 @@ public void Build(BuildContext ctx, in DpFactory factory)
                     code.AppendLine($"{variableNameProvider.GetOverrideVariableName(@override.Source)} = {@override.Source.ValueExpression};");
                 }
 
+                foreach (var argument in initializationArgs)
+                foreach (var argStatement in GetArgsStatements(argument))
+                {
+                    ctx.StatementBuilder.Build(ctx with { Variable = argStatement.Current }, argStatement);
+                }
+
                 var initializersWalker = initializersWalkerFactory().Ininitialize(initialization.VariableName, initializationArgsEnum);
                 initializersWalker.VisitInitializer(injectionsCtx, initializer);
                 continue;
@@ -313,4 +326,27 @@ public void Build(BuildContext ctx, in DpFactory factory)
 
         ctx.Code.AppendLines(ctx.BuildTools.OnCreated(ctx, variable));
     }
+
+    private static IEnumerable<IStatement> GetArgsStatements(IStatement statement)
+    {
+        var result = new Stack<IStatement>();
+        var statements = new Stack<IStatement>();
+        statements.Push(statement);
+        while (statements.TryPop(out var nextStatement))
+        {
+            var variable = nextStatement.Current;
+            if (variable.HasCycledReference && variable.Node.Lifetime == Lifetime.PerBlock)
+            {
+                continue;
+            }
+
+            result.Push(nextStatement);
+            foreach (var arg in variable.Args)
+            {
+                statements.Push(arg);
+            }
+        }
+
+        return result;
+    }
 }