fix: Resolve bugs introduced by PR #68 (#139)

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# Summary
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#68 missed updating vllm_backend.py for the change to
`_build_json_based_regex()` arguments, fix them now.

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Ensure that the following pass:

- [x] `make format && make lint` or via prek validation.
- [x] `make test` passes locally
- [ ] `make test-e2e` passes locally
- [ ] `make test-ci-container` passes locally (recommended)

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- [ ] New or updated tests for any fix or new behavior
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## Other Notes

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- Closes #<issue>

---------

Signed-off-by: memadi <memadi@nvidia.com>

Author: memadi-nv

src/nemo_safe_synthesizer/generation/vllm_backend.py

@@ -118,9 +118,9 @@ def _build_structured_output_params(self) -> StructuredOutputsParams | None:
             logger.info("Structured generation is enabled, using a regex to enforce the schema")
             regex = build_json_based_regex(
                 self.schema,
+                self.config,
                 self.model_metadata.prompt_config.bos_token,
                 self.model_metadata.prompt_config.eos_token,
-                group_by=self.config.data.group_training_examples_by is not None,
             )
             params["regex"] = regex
         elif self.config.generation.structured_generation_schema_method == "json_schema":

tests/generation/test_vllm_backend.py

@@ -158,12 +158,11 @@ def test_returns_params_with_regex_when_regex_method(
             return_value="test_regex_pattern",
         ) as mock_build_regex:
             result = backend._build_structured_output_params()
-
             mock_build_regex.assert_called_once_with(
                 mock_schema,
+                params_with_structured_generation_regex,
                 mock_model_metadata.prompt_config.bos_token,
                 mock_model_metadata.prompt_config.eos_token,
-                group_by=False,
             )
             assert result is not None
             assert result.regex == "test_regex_pattern"
@@ -179,10 +178,10 @@ def test_returns_params_with_json_when_json_schema_method(
         assert result is not None
         assert result.json == mock_schema
 
-    def test_group_by_passed_when_grouping_enabled(
+    def test_config_with_grouping_passed_to_build_regex(
         self, params_with_structured_generation_regex, mock_model_metadata, mock_schema, mock_workdir
     ):
-        """Test that group_by=True is passed when group_training_examples_by is set."""
+        """Test that config with group_training_examples_by set is passed to build_json_based_regex."""
         params_with_structured_generation_regex.data.group_training_examples_by = "category"
         backend = create_backend(
             params_with_structured_generation_regex, mock_model_metadata, mock_schema, mock_workdir
@@ -195,8 +194,8 @@ def test_group_by_passed_when_grouping_enabled(
             backend._build_structured_output_params()
 
             mock_build_regex.assert_called_once()
-            _, kwargs = mock_build_regex.call_args
-            assert kwargs.get("group_by") is True
+            call_args, _ = mock_build_regex.call_args
+            assert call_args[1].data.group_training_examples_by == "category"
 
 
 class TestResolveTemperature: