C# roslyn - How to obtain the type information in the syntax tree

Question

How to obtain the type information of "t"?

How to get the type name of t

        class Test
        {
            void main()
            {
                var t = new Test();

                t.Equals(null);// object.Equals

                //How do I get the type of "t" ?
            }
        }

        private static void AnalyzeNode(SyntaxNodeAnalysisContext context)
        {
            var invocationExpr = (InvocationExpressionSyntax)context.Node;
            var memberAccessExpr = invocationExpr.Expression as MemberAccessExpressionSyntax;
            if (memberAccessExpr == null)
                return;
            if (memberAccessExpr.Name.ToString() != nameof(object.Equals))
                return;
            var memberSymbol = context.SemanticModel.GetSymbolInfo(memberAccessExpr).Symbol as IMethodSymbol;
            if (memberSymbol == null)
                return;

            _ = memberSymbol.ContainingType.SpecialType;// Object
        }

I don't know why, but I cannot enter the breakpoint when debugging with vs. So I can only debug in this way, but I can't find the correct method.

var str = memberSymbol.ContainingSymbol?.Name + Environment.NewLine
                 + memberSymbol.AssociatedSymbol?.Name + Environment.NewLine
                 + memberSymbol.ContainingType?.Name + Environment.NewLine
                 + memberSymbol.ContainingType?.SpecialType + Environment.NewLine
                 + memberSymbol.ContainingType?.ContainingType?.Name + Environment.NewLine
                 + memberSymbol.ContainingType?.TypeKind + Environment.NewLine
                 + memberSymbol.ContainingType?.OriginalDefinition?.Name + Environment.NewLine
                 + memberSymbol.ContainingType?.BaseType?.Name + Environment.NewLine
                 + memberSymbol.ContainingType?.MetadataName + Environment.NewLine
                 + memberSymbol.ContainingType?.ContainingAssembly?.Name + Environment.NewLine
                 + string.Join(" ", memberSymbol.ContainingType?.MemberNames ?? Enumerable.Empty<string>()) + Environment.NewLine
                 + "***************" + Environment.NewLine
                 + invocationExpr.FullSpan.ToString() + Environment.NewLine
                ;

            File.WriteAllText(@"xxxxxxx", str);

I want to obtain "Test" type information or type string