private void AddToCallerCalleeMap()

in src/Microsoft.VisualStudio.Threading.Analyzers.CSharp/VSTHRD010MainThreadUsageAnalyzer.cs [230:285]
50 lines of code
12 McCabe index (conditional complexity)

        private void AddToCallerCalleeMap(OperationAnalysisContext context, Dictionary<IMethodSymbol, List<CallInfo>> callerToCalleeMap)
        {
            if (CSharpUtils.IsWithinNameOf(context.Operation.Syntax))
            {
                return;
            }

            IMethodSymbol? GetPropertyAccessor(IPropertySymbol? propertySymbol)
            {
                if (propertySymbol is object)
                {
                    return CSharpUtils.IsOnLeftHandOfAssignment(context.Operation.Syntax)
                        ? propertySymbol.SetMethod
                        : propertySymbol.GetMethod;
                }

                return null;
            }

            ISymbol? targetMethod = null;
            SyntaxNode locationToBlame = context.Operation.Syntax;
            switch (context.Operation)
            {
                case IInvocationOperation invocationOperation:
                    targetMethod = invocationOperation.TargetMethod;
                    locationToBlame = this.languageUtils.IsolateMethodName(invocationOperation);
                    break;
                case IPropertyReferenceOperation propertyReference:
                    targetMethod = GetPropertyAccessor(propertyReference.Property);
                    break;
                case IEventAssignmentOperation eventAssignmentOperation:
                    IOperation eventReferenceOp = eventAssignmentOperation.EventReference;
                    if (eventReferenceOp is IEventReferenceOperation eventReference)
                    {
                        targetMethod = eventAssignmentOperation.Adds
                            ? eventReference.Event.AddMethod
                            : eventReference.Event.RemoveMethod;
                        locationToBlame = eventReference.Syntax;
                    }

                    break;
            }

            if (context.ContainingSymbol is IMethodSymbol caller && targetMethod is IMethodSymbol callee)
            {
                lock (callerToCalleeMap)
                {
                    if (!callerToCalleeMap.TryGetValue(caller, out List<CallInfo> callees))
                    {
                        callerToCalleeMap[caller] = callees = new List<CallInfo>();
                    }

                    callees.Add(new CallInfo(methodSymbol: callee, invocationSyntax: locationToBlame));
                }
            }
        }