Expose GetCreateRequestMethod and GetMethodCollectionByOperation

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/ClientProvider.cs

@@ -51,6 +51,9 @@ private record OAuth2Fields(FieldProvider AuthField, FieldProvider Authorization
         private readonly IReadOnlyList<InputParameter> _allClientParameters;
         private Lazy<IReadOnlyList<FieldProvider>> _additionalClientFields;
 
+        private Dictionary<InputOperation, ScmMethodProviderCollection>? _methodCache;
+        private Dictionary<InputOperation, ScmMethodProviderCollection> MethodCache => _methodCache ??= [];
+
         private Lazy<ParameterProvider?> ClientOptionsParameter { get; }
 
         protected override FormattableString Description { get; }
@@ -505,6 +508,12 @@ [.. primaryCtorOrderedParams.Select(p => p.InitializationValue ?? p)
                 this);
         }
 
+        public ScmMethodProviderCollection GetMethodCollectionByOperation(InputOperation operation)
+        {
+            _ = Methods; // Ensure methods are built
+            return MethodCache[operation];
+        }
+
         protected override ScmMethodProvider[] BuildMethods()
         {
             var subClients = _subClients.Value;
@@ -516,6 +525,7 @@ protected override ScmMethodProvider[] BuildMethods()
                 var clientMethods = ScmCodeModelGenerator.Instance.TypeFactory.CreateMethods(serviceMethod, this);
                 if (clientMethods != null)
                 {
+                    MethodCache[serviceMethod.Operation] = clientMethods;
                     methods.AddRange(clientMethods);
                 }
             }

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/CollectionResultDefinition.cs

@@ -36,7 +36,7 @@ internal class CollectionResultDefinition : TypeProvider
 
         private readonly string _itemsPropertyName;
         private readonly InputPagingServiceMetadata _paging;
-        private readonly FieldProvider[] _requestFields;
+        private readonly IReadOnlyList<FieldProvider> _requestFields;
         private readonly IReadOnlyList<ParameterProvider> _createRequestParameters;
         private readonly int? _nextTokenParameterIndex;
 
@@ -73,7 +73,7 @@ public CollectionResultDefinition(ClientProvider client, InputPagingServiceMetho
                 }
             }
 
-            _requestFields = fields.ToArray();
+            _requestFields = fields;
 
             _itemModelType = itemModelType;
             _isAsync = isAsync;
@@ -431,7 +431,7 @@ private MethodBodyStatement[] AssignAndCheckNextPageVariable(ClientResponseApi r
         private ScopedApi<PipelineMessage> InvokeCreateRequestForNextLink(ValueExpression nextPageUri) => _clientField.Invoke(
             $"Create{_operation.Name.ToCleanName()}Request",
             // we replace the first argument (the initialUri) with the nextPageUri
-            [nextPageUri, .. _requestFields[1..]])
+            [nextPageUri, .. _requestFields.Skip(1)])
             .As<PipelineMessage>();
 
         private ScopedApi<PipelineMessage> InvokeCreateRequestForContinuationToken(ValueExpression nextToken)

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/RestClientProvider.cs

@@ -514,7 +514,7 @@ private static List<int> GetSuccessStatusCodes(InputOperation operation)
             return [.. statusCodes.OrderBy(i => i)];
         }
 
-        internal MethodProvider GetCreateRequestMethod(InputOperation operation)
+        public MethodProvider GetCreateRequestMethod(InputOperation operation)
         {
             _ = Methods; // Ensure methods are built
             return MethodCache[operation];