rename to str output parser (#8373)

libs/langchain/langchain/chains/llm.py

@@ -20,8 +20,8 @@ from langchain.schema import (
     BaseLLMOutputParser,
     BasePromptTemplate,
     LLMResult,
-    NoOpOutputParser,
     PromptValue,
+    StrOutputParser,
 )
 from langchain.schema.language_model import BaseLanguageModel
 from langchain.utils.input import get_colored_text
@@ -50,7 +50,7 @@ class LLMChain(Chain):
     llm: BaseLanguageModel
     """Language model to call."""
     output_key: str = "text"  #: :meta private:
-    output_parser: BaseLLMOutputParser = Field(default_factory=NoOpOutputParser)
+    output_parser: BaseLLMOutputParser = Field(default_factory=StrOutputParser)
     """Output parser to use.
     Defaults to one that takes the most likely string but does not change it 
     otherwise."""

libs/langchain/langchain/prompts/loading.py

@@ -10,7 +10,7 @@ import yaml
 from langchain.output_parsers.regex import RegexParser
 from langchain.prompts.few_shot import FewShotPromptTemplate
 from langchain.prompts.prompt import PromptTemplate
-from langchain.schema import BaseLLMOutputParser, BasePromptTemplate, NoOpOutputParser
+from langchain.schema import BaseLLMOutputParser, BasePromptTemplate, StrOutputParser
 from langchain.utilities.loading import try_load_from_hub
 
 URL_BASE = "https://raw.githubusercontent.com/hwchase17/langchain-hub/master/prompts/"
@@ -80,7 +80,7 @@ def _load_output_parser(config: dict) -> dict:
         if output_parser_type == "regex_parser":
             output_parser: BaseLLMOutputParser = RegexParser(**_config)
         elif output_parser_type == "default":
-            output_parser = NoOpOutputParser(**_config)
+            output_parser = StrOutputParser(**_config)
         else:
             raise ValueError(f"Unsupported output parser {output_parser_type}")
         config["output_parser"] = output_parser

libs/langchain/langchain/schema/__init__.py

@@ -24,8 +24,8 @@ from langchain.schema.output import (
 from langchain.schema.output_parser import (
     BaseLLMOutputParser,
     BaseOutputParser,
-    NoOpOutputParser,
     OutputParserException,
+    StrOutputParser,
 )
 from langchain.schema.prompt import PromptValue
 from langchain.schema.prompt_template import BasePromptTemplate, format_document
@@ -62,7 +62,7 @@ __all__ = [
     "RUN_KEY",
     "Memory",
     "OutputParserException",
-    "NoOpOutputParser",
+    "StrOutputParser",
     "BaseOutputParser",
     "BaseLLMOutputParser",
     "BasePromptTemplate",

libs/langchain/langchain/schema/output_parser.py

@@ -137,8 +137,8 @@ class BaseOutputParser(BaseLLMOutputParser, Runnable[Union[str, BaseMessage], T]
         return output_parser_dict
 
 
-class NoOpOutputParser(BaseOutputParser[str]):
-    """'No operation' OutputParser that returns the text as is."""
+class StrOutputParser(BaseOutputParser[str]):
+    """OutputParser that parses LLMResult into the top likely string.."""
 
     @property
     def lc_serializable(self) -> bool:
@@ -155,6 +155,10 @@ class NoOpOutputParser(BaseOutputParser[str]):
         return text
 
 
+# TODO: Deprecate
+NoOpOutputParser = StrOutputParser
+
+
 class OutputParserException(ValueError):
     """Exception that output parsers should raise to signify a parsing error.