fix evaluation parse test (#8859)

# What
- fix evaluation parse test

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  - Description: Fix evaluation parse test
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libs/langchain/langchain/evaluation/comparison/eval_chain.py

@@ -100,14 +100,14 @@ class PairwiseStringResultOutputParser(BaseOutputParser[dict]):
         """
         return "pairwise_string_result"
 
-    def parse(self, text: str) -> Any:
+    def parse(self, text: str) -> Dict[str, Any]:
         """Parse the output text.
 
         Args:
             text (str): The output text to parse.
 
         Returns:
-            Any: The parsed output.
+            Dict: The parsed output.
 
         Raises:
             ValueError: If the verdict is invalid.

libs/langchain/langchain/evaluation/criteria/eval_chain.py

@@ -65,14 +65,14 @@ class CriteriaResultOutputParser(BaseOutputParser[dict]):
     def _type(self) -> str:
         return "criteria_result"
 
-    def parse(self, text: str) -> Any:
+    def parse(self, text: str) -> Dict[str, Any]:
         """Parse the output text.
 
         Args:
             text (str): The output text to parse.
 
         Returns:
-            Any: The parsed output.
+            Dict: The parsed output.
         """
         parsed = text.strip().rsplit("\n", maxsplit=1)
         if len(parsed) == 1:

libs/langchain/tests/unit_tests/evaluation/comparison/test_eval_chain.py

@@ -8,6 +8,7 @@ import pytest
 from langchain.evaluation.comparison.eval_chain import (
     LabeledPairwiseStringEvalChain,
     PairwiseStringEvalChain,
+    PairwiseStringResultOutputParser,
     resolve_pairwise_criteria,
 )
 from langchain.evaluation.criteria.eval_chain import Criteria
@@ -27,6 +28,45 @@ def test_resolve_criteria_list_enum() -> None:
     assert set(val.keys()) == set(c.value for c in list(Criteria))
 
 
+def test_PairwiseStringResultOutputParser_parse() -> None:
+    output_parser = PairwiseStringResultOutputParser()
+    text = """I like pie better than cake.
+[[A]]"""
+    got = output_parser.parse(text)
+    want = {
+        "reasoning": "I like pie better than cake.",
+        "value": "A",
+        "score": 1,
+    }
+    assert got.get("reasoning") == want["reasoning"]
+    assert got.get("value") == want["value"]
+    assert got.get("score") == want["score"]
+
+    text = """I like cake better than pie.
+[[B]]"""
+    got = output_parser.parse(text)
+    want = {
+        "reasoning": "I like cake better than pie.",
+        "value": "B",
+        "score": 0,
+    }
+    assert got.get("reasoning") == want["reasoning"]
+    assert got.get("value") == want["value"]
+    assert got.get("score") == want["score"]
+
+    text = """I like cake and pie.
+[[C]]"""
+    got = output_parser.parse(text)
+    want = {
+        "reasoning": "I like cake and pie.",
+        "value": None,
+        "score": 0.5,
+    }
+    assert got.get("reasoning") == want["reasoning"]
+    assert got.get("value") == want["value"]
+    assert got.get("score") == want["score"]
+
+
 def test_pairwise_string_comparison_chain() -> None:
     llm = FakeLLM(
         queries={

libs/langchain/tests/unit_tests/evaluation/criteria/test_eval_chain.py

@@ -7,6 +7,7 @@ from langchain.evaluation.criteria.eval_chain import (
     _SUPPORTED_CRITERIA,
     Criteria,
     CriteriaEvalChain,
+    CriteriaResultOutputParser,
     LabeledCriteriaEvalChain,
 )
 from langchain.evaluation.schema import StringEvaluator
@@ -23,6 +24,34 @@ def test_resolve_criteria_str() -> None:
     }
 
 
+def test_CriteriaResultOutputParser_parse() -> None:
+    output_parser = CriteriaResultOutputParser()
+    text = """Here is my step-by-step reasoning for the given criteria:
+The criterion is: "Do you like cake?" I like cake.
+Y"""
+    got = output_parser.parse(text)
+    want = {
+        "reasoning": """Here is my step-by-step reasoning for the given criteria:
+The criterion is: "Do you like cake?" I like cake.""",
+        "value": "Y",
+        "score": 1,
+    }
+    assert got.get("reasoning") == want["reasoning"]
+    assert got.get("value") == want["value"]
+    assert got.get("score") == want["score"]
+
+    text = "Y"
+    got = output_parser.parse(text)
+    want = {
+        "reasoning": "",
+        "value": "Y",
+        "score": 1,
+    }
+    assert got.get("reasoning") == want["reasoning"]
+    assert got.get("value") == want["value"]
+    assert got.get("score") == want["score"]
+
+
 @pytest.mark.parametrize("criterion", list(Criteria))
 def test_resolve_criteria_enum(criterion: Criteria) -> None:
     assert CriteriaEvalChain.resolve_criteria(criterion) == {