Added more tests for Quantization24SparseW4A16 (#1434)

SUMMARY:
Added following validations for each stage:
1. Check if recipe.yaml file exists
2. Check if config.json file exists
3. Check if `quantization_config` field is present in config.json
4. Check if format is set correctly


TEST:
- The current setup pass the test. 
Manually removed `format` and it failed expectedly. 

QUESTION:
- Any more fields I should check for? 
- Naming?

---------

Signed-off-by: shanjiaz <[email protected]>

Author: shanjiaz

tests/examples/test_quantization_2of4_sparse_w4a16.py

@@ -4,6 +4,7 @@
 from pathlib import Path
 
 import pytest
+from transformers import AutoConfig
 
 from tests.examples.utils import (
     ReadMe,
@@ -28,19 +29,71 @@ class TestQuantization24SparseW4A16:
 
     def test_doc_example_command(self, example_dir: str, tmp_path: Path):
         """
-        Test for the example command in the README.
+        Validates the quantization_2of4_sparse_w4a16 example by executing the README
+        command and verifying output artifacts for each processing stage.
         """
         readme_path = Path.cwd() / example_dir / "README.md"
         readme = ReadMe(readme_path)
 
         command = readme.get_code_block_content(position=2, lang="shell")
-        assert command.startswith("python")
+        assert command.startswith("python"), (
+            "Expected shell command to start with 'python'"
+        )
 
         command = shlex.split(command)
         result = copy_and_run_command(tmp_path, example_dir, command)
-
         assert result.returncode == 0, gen_cmd_fail_message(command, result)
 
+        output_dir = Path("output_llama7b_2of4_w4a16_channel")
+
+        stages = {
+            "quantization": {
+                "path": Path("quantization_stage"),
+                "format": "marlin-24",
+            },
+            "sparsity": {
+                "path": Path("sparsity_stage"),
+                "format": "sparse-24-bitmask",
+            },
+            "finetuning": {
+                "path": Path("finetuning_stage"),
+                "format": "sparse-24-bitmask",
+            },
+        }
+
+        for stage, stage_info in stages.items():
+            stage_path = (
+                tmp_path / example_dir / output_dir / stage_info["path"]
+            )
+            recipe_path = stage_path / "recipe.yaml"
+            config_path = stage_path / "config.json"
+
+            assert recipe_path.exists(), (
+                f"Missing recipe file in {stage}: {recipe_path}"
+            )
+            assert config_path.exists(), (
+                f"Missing config file in {stage}: {config_path}"
+            )
+
+            config = AutoConfig.from_pretrained(stage_path)
+            assert config is not None, f"Failed to load config in {stage}"
+
+            quant_config = getattr(config, "quantization_config", {})
+            if stage == "quantization":
+                actual_format = quant_config.get("format")
+            else:
+                actual_format = quant_config.get(
+                    "sparsity_config", {}
+                ).get("format")
+
+            assert actual_format, (
+                f"Missing expected format field in {stage} config"
+            )
+            assert actual_format == stage_info["format"], (
+                f"Unexpected format in {stage}: got '{actual_format}', "
+                f"expected '{stage_info['format']}'"
+            )
+
     def test_alternative_recipe(self, example_dir: str, tmp_path: Path):
         """
         Test for the example command in the README with the alternative recipe file.