GetField

Author: JohanLarsson

ReflectionAnalyzers/Helpers/Reflection/FieldInfo.cs

@@ -24,8 +24,7 @@ internal FieldInfo(INamedTypeSymbol reflectedType, IFieldSymbol field)
             return expression switch
             {
                 InvocationExpressionSyntax invocation
-                    when GetX.TryMatchGetField(invocation, semanticModel, cancellationToken, out var member, out _, out _) &&
-                         member is { ReflectedType: { } reflectedType, Symbol: IFieldSymbol field }
+                    when GetField.Match(invocation, semanticModel, cancellationToken) is { Member: { ReflectedType: { } reflectedType, Symbol: IFieldSymbol field } }
                     => new FieldInfo(reflectedType, field),
                 IdentifierNameSyntax identifierName => FindAssigned(identifierName),
                 MemberAccessExpressionSyntax memberAccess => FindAssigned(memberAccess),

ReflectionAnalyzers/Helpers/Reflection/GetField.cs

@@ -0,0 +1,77 @@
+namespace ReflectionAnalyzers;
+
+using System.Threading;
+using Gu.Roslyn.AnalyzerExtensions;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+
+internal readonly struct GetField
+{
+    internal readonly InvocationExpressionSyntax Invocation;
+    internal readonly IMethodSymbol Target;
+    internal readonly ReflectedMember Member;
+    internal readonly Name Name;
+    internal readonly Flags Flags;
+
+    private GetField(InvocationExpressionSyntax invocation, IMethodSymbol target, ReflectedMember member, Name name, Flags flags)
+    {
+        this.Invocation = invocation;
+        this.Target = target;
+        this.Member = member;
+        this.Name = name;
+        this.Flags = flags;
+    }
+
+    internal IFieldSymbol? Single => this.Member.Match == FilterMatch.Single ? (IFieldSymbol)this.Member.Symbol! : null;
+
+    /// <summary>
+    /// Check if <paramref name="candidate"/> is a call to Type.GetField.
+    /// </summary>
+    internal static GetField? Match(ExpressionSyntax candidate, SemanticModel semanticModel, CancellationToken cancellationToken)
+    {
+        return candidate switch
+        {
+            InvocationExpressionSyntax invocation
+                => Match(invocation, semanticModel, cancellationToken),
+            PostfixUnaryExpressionSyntax { RawKind: (int)SyntaxKind.SuppressNullableWarningExpression, Operand: InvocationExpressionSyntax invocation }
+                => Match(invocation, semanticModel, cancellationToken),
+            MemberAccessExpressionSyntax { Expression: { } inner }
+                => Match(inner, semanticModel, cancellationToken),
+            MemberBindingExpressionSyntax { Parent.Parent: ConditionalAccessExpressionSyntax { Expression: InvocationExpressionSyntax invocation } }
+                => Match(invocation, semanticModel, cancellationToken),
+            IdentifierNameSyntax identifierName
+                when semanticModel.TryGetSymbol(identifierName, cancellationToken, out ILocalSymbol? local) &&
+                     AssignedValue.FindSingle(local, semanticModel, cancellationToken) is { } value
+                => Match(value, semanticModel, cancellationToken),
+            _ => null,
+        };
+    }
+
+    /// <summary>
+    /// Check if <paramref name="candidate"/> is a call to Type.GetField.
+    /// </summary>
+    internal static GetField? Match(InvocationExpressionSyntax candidate, SemanticModel semanticModel, CancellationToken cancellationToken)
+    {
+        if (candidate.TryGetTarget(KnownSymbol.Type.GetField, semanticModel, cancellationToken, out var target))
+        {
+            if (ReflectedMember.TryGetType(candidate, semanticModel, cancellationToken, out var type, out var typeSource) &&
+                Name.TryCreate(candidate, target, semanticModel, cancellationToken, out var name) &&
+                Flags.TryCreate(candidate, target, semanticModel, cancellationToken, out var flags) &&
+                ReflectedMember.TryCreate(target, candidate, type, typeSource, name, flags.Effective, Types.Any, semanticModel.Compilation, out var member))
+            {
+                return new GetField(candidate, target, member, name, flags);
+            }
+
+            if (Flags.TryCreate(candidate, target, semanticModel, cancellationToken, out flags) &&
+                flags.AreInSufficient)
+            {
+                _ = Name.TryCreate(candidate, target, semanticModel, cancellationToken, out name);
+                member = new ReflectedMember(type, typeSource, null, target, candidate, FilterMatch.InSufficientFlags);
+                return new GetField(candidate, target, member, name, flags);
+            }
+        }
+
+        return null;
+    }
+}

ReflectionAnalyzers/Helpers/Reflection/Type.cs

@@ -166,11 +166,9 @@ when GetMethod.Match(invocation, recursion.SemanticModel, recursion.Cancellation
                     result = single.ReturnType;
                     return true;
                 case MemberAccessExpressionSyntax { Expression: InvocationExpressionSyntax invocation, Name: { Identifier: { ValueText: "FieldType" } } } memberAccess
-                    when GetX.TryMatchGetField(invocation, recursion.SemanticModel, recursion.CancellationToken, out var reflectedMember, out _, out _) &&
-                         reflectedMember.Match == FilterMatch.Single &&
-                         reflectedMember.Symbol is IFieldSymbol field:
+                    when GetField.Match(invocation, recursion.SemanticModel, recursion.CancellationToken) is { Single:{} single }:
                     source = memberAccess;
-                    result = field.Type;
+                    result = single.Type;
                     return true;
                 case MemberAccessExpressionSyntax { Expression: InvocationExpressionSyntax invocation, Name: { Identifier: { ValueText: "PropertyType" } } } memberAccess
                     when GetX.TryMatchGetProperty(invocation, recursion.SemanticModel, recursion.CancellationToken, out var reflectedMember, out _, out _, out _) &&