feat: Add copyWith method to all RunnableOptions subclasses (#531)

packages/langchain_core/lib/src/chat_models/fake.dart

@@ -2,6 +2,7 @@ import 'package:collection/collection.dart';
 
 import '../../language_models.dart';
 import '../prompts/types.dart';
+import '../tools/base.dart';
 import 'base.dart';
 import 'types.dart';
 
@@ -85,6 +86,8 @@ class FakeChatModelOptions extends ChatModelOptions {
   const FakeChatModelOptions({
     super.model,
     this.metadata,
+    super.tools,
+    super.toolChoice,
     super.concurrencyLimit,
   });
 
@@ -95,11 +98,15 @@ class FakeChatModelOptions extends ChatModelOptions {
   FakeChatModelOptions copyWith({
     final String? model,
     final Map<String, dynamic>? metadata,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
     final int? concurrencyLimit,
   }) {
     return FakeChatModelOptions(
       model: model ?? this.model,
       metadata: metadata ?? this.metadata,
+      tools: tools ?? this.tools,
+      toolChoice: toolChoice ?? this.toolChoice,
       concurrencyLimit: concurrencyLimit ?? this.concurrencyLimit,
     );
   }
@@ -223,6 +230,8 @@ class FakeEchoChatModelOptions extends ChatModelOptions {
     super.model,
     this.metadata,
     this.throwRandomError = false,
+    super.tools,
+    super.toolChoice,
     super.concurrencyLimit,
   });
 
@@ -237,12 +246,16 @@ class FakeEchoChatModelOptions extends ChatModelOptions {
     final String? model,
     final Map<String, dynamic>? metadata,
     final bool? throwRandomError,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
     final int? concurrencyLimit,
   }) {
     return FakeEchoChatModelOptions(
       model: model ?? this.model,
       metadata: metadata ?? this.metadata,
       throwRandomError: throwRandomError ?? this.throwRandomError,
+      tools: tools ?? this.tools,
+      toolChoice: toolChoice ?? this.toolChoice,
       concurrencyLimit: concurrencyLimit ?? this.concurrencyLimit,
     );
   }

packages/langchain_core/lib/src/chat_models/types.dart

@@ -22,6 +22,14 @@ abstract class ChatModelOptions extends LanguageModelOptions {
 
   /// Controls which (if any) tool is called by the model.
   final ChatToolChoice? toolChoice;
+
+  @override
+  ChatModelOptions copyWith({
+    final String? model,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
+    final int? concurrencyLimit,
+  });
 }
 
 /// {@template chat_result}

packages/langchain_core/lib/src/language_models/types.dart

@@ -17,6 +17,12 @@ abstract class LanguageModelOptions extends BaseLangChainOptions {
   /// ID of the language model to use.
   /// Check the provider's documentation for available models.
   final String? model;
+
+  @override
+  LanguageModelOptions copyWith({
+    final String? model,
+    final int? concurrencyLimit,
+  });
 }
 
 /// {@template language_model}

packages/langchain_core/lib/src/llms/fake.dart

@@ -7,11 +7,11 @@ import 'types.dart';
 /// Fake LLM for testing.
 /// You can pass in a list of responses to return in order when called.
 /// {@endtemplate}
-class FakeLLM extends SimpleLLM {
+class FakeLLM extends SimpleLLM<FakeLLMOptions> {
   /// {@macro fake_list_llm}
   FakeLLM({
     required this.responses,
-  }) : super(defaultOptions: const LLMOptions());
+  }) : super(defaultOptions: const FakeLLMOptions());
 
   /// Responses to return in order when called.
   final List<String> responses;
@@ -60,13 +60,35 @@ class FakeLLM extends SimpleLLM {
   }
 }
 
+/// {@template fake_llm_options}
+/// Fake LLM options for testing.
+/// {@endtemplate}
+class FakeLLMOptions extends LLMOptions {
+  /// {@macro fake_llm_options}
+  const FakeLLMOptions({
+    super.model,
+    super.concurrencyLimit,
+  });
+
+  @override
+  FakeLLMOptions copyWith({
+    final String? model,
+    final int? concurrencyLimit,
+  }) {
+    return FakeLLMOptions(
+      model: model ?? this.model,
+      concurrencyLimit: concurrencyLimit ?? this.concurrencyLimit,
+    );
+  }
+}
+
 /// {@template fake_echo_llm}
 /// Fake LLM for testing.
 /// It just returns the prompt or streams it char by char.
 /// {@endtemplate}
-class FakeEchoLLM extends BaseLLM {
+class FakeEchoLLM extends BaseLLM<FakeLLMOptions> {
   /// {@macro fake_echo_llm}
-  const FakeEchoLLM() : super(defaultOptions: const LLMOptions());
+  const FakeEchoLLM() : super(defaultOptions: const FakeLLMOptions());
 
   @override
   String get modelType => 'fake-echo';
@@ -122,11 +144,11 @@ class FakeEchoLLM extends BaseLLM {
 /// Fake LLM for testing.
 /// It returns the string returned by the [handler] function.
 /// {@endtemplate}
-class FakeHandlerLLM extends SimpleLLM {
+class FakeHandlerLLM extends SimpleLLM<FakeLLMOptions> {
   /// {@macro fake_handler_llm}
   FakeHandlerLLM({
     required this.handler,
-  }) : super(defaultOptions: const LLMOptions());
+  }) : super(defaultOptions: const FakeLLMOptions());
 
   /// Function called to generate the response.
   final String Function(

packages/langchain_core/lib/src/llms/types.dart

@@ -6,7 +6,7 @@ import '../language_models/types.dart';
 /// Options to pass into the LLM.
 /// {@endtemplate}
 @immutable
-class LLMOptions extends LanguageModelOptions {
+abstract class LLMOptions extends LanguageModelOptions {
   /// {@macro llm_options}
   const LLMOptions({
     super.model,

packages/langchain_core/lib/src/retrievers/types.dart

@@ -21,10 +21,22 @@ class VectorStoreRetrieverOptions extends RetrieverOptions {
   /// {@macro vector_store_retriever_options}
   const VectorStoreRetrieverOptions({
     this.searchType = const VectorStoreSimilaritySearch(),
+    super.concurrencyLimit,
   });
 
   /// The type of search to perform, either:
   /// - [VectorStoreSearchType.similarity] (default)
   /// - [VectorStoreSearchType.mmr]
   final VectorStoreSearchType searchType;
+
+  @override
+  VectorStoreRetrieverOptions copyWith({
+    final VectorStoreSearchType? searchType,
+    final int? concurrencyLimit,
+  }) {
+    return VectorStoreRetrieverOptions(
+      searchType: searchType ?? this.searchType,
+      concurrencyLimit: concurrencyLimit ?? this.concurrencyLimit,
+    );
+  }
 }

packages/langchain_core/test/runnables/binding_test.dart

@@ -4,6 +4,7 @@ import 'package:langchain_core/language_models.dart';
 import 'package:langchain_core/output_parsers.dart';
 import 'package:langchain_core/prompts.dart';
 import 'package:langchain_core/runnables.dart';
+import 'package:langchain_core/tools.dart';
 import 'package:test/test.dart';
 
 void main() {
@@ -123,4 +124,14 @@ class _FakeOptionsChatModelOptions extends ChatModelOptions {
   const _FakeOptionsChatModelOptions(this.stop);
 
   final String stop;
+
+  @override
+  ChatModelOptions copyWith({
+    final String? model,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
+    final int? concurrencyLimit,
+  }) {
+    return _FakeOptionsChatModelOptions(stop);
+  }
 }

packages/langchain_google/lib/src/chat_models/vertex_ai/types.dart

@@ -1,5 +1,6 @@
 import 'package:collection/collection.dart';
 import 'package:langchain_core/chat_models.dart';
+import 'package:langchain_core/tools.dart';
 import 'package:meta/meta.dart';
 
 /// {@template chat_vertex_ai_options}
@@ -108,6 +109,8 @@ class ChatVertexAIOptions extends ChatModelOptions {
     final List<String>? stopSequences,
     final int? candidateCount,
     final List<ChatExample>? examples,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
     final int? concurrencyLimit,
   }) {
     return ChatVertexAIOptions(

packages/langchain_mistralai/lib/src/chat_models/types.dart

@@ -1,4 +1,5 @@
 import 'package:langchain_core/chat_models.dart';
+import 'package:langchain_core/tools.dart';
 import 'package:meta/meta.dart';
 
 /// {@template chat_mistral_ai_options}
@@ -54,6 +55,8 @@ class ChatMistralAIOptions extends ChatModelOptions {
     final int? maxTokens,
     final bool? safePrompt,
     final int? randomSeed,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
     final int? concurrencyLimit,
   }) {
     return ChatMistralAIOptions(

packages/langchain_ollama/lib/src/chat_models/chat_ollama/types.dart

@@ -1,5 +1,6 @@
 import 'package:collection/collection.dart';
 import 'package:langchain_core/chat_models.dart';
+import 'package:langchain_core/tools.dart';
 import 'package:meta/meta.dart';
 
 import '../../../langchain_ollama.dart';
@@ -247,6 +248,8 @@ class ChatOllamaOptions extends ChatModelOptions {
     final bool? useMmap,
     final bool? useMlock,
     final int? numThread,
+    final List<ToolSpec>? tools,
+    final ChatToolChoice? toolChoice,
     final int? concurrencyLimit,
   }) {
     return ChatOllamaOptions(
@@ -283,6 +286,8 @@ class ChatOllamaOptions extends ChatModelOptions {
       useMmap: useMmap ?? this.useMmap,
       useMlock: useMlock ?? this.useMlock,
       numThread: numThread ?? this.numThread,
+      tools: tools ?? this.tools,
+      toolChoice: toolChoice ?? this.toolChoice,
       concurrencyLimit: concurrencyLimit ?? this.concurrencyLimit,
     );
   }