Add test for config conversion for checkpointing

Author: coolkp

src/maxdiffusion/configs/base_wan_14b.yml

@@ -60,7 +60,16 @@ attention: 'flash' # Supported attention: dot_product, flash, cudnn_flash_te, ri
 flash_min_seq_length: 4096
 dropout: 0.1
 
-flash_block_sizes: {}
+flash_block_sizes: {
+  "block_q" : 1024,
+  "block_kv_compute" : 256,
+  "block_kv" : 1024,
+  "block_q_dkv" : 1024,
+  "block_kv_dkv" : 1024,
+  "block_kv_dkv_compute" : 256,
+  "block_q_dq" : 1024,
+  "block_kv_dq" : 1024
+}
 # Use on v6e
 # flash_block_sizes: {
 #   "block_q" : 3024,

src/maxdiffusion/tests/configuration_utils_test.py

@@ -0,0 +1,42 @@
+import json
+import os
+
+from .. import pyconfig
+from ..configuration_utils import ConfigMixin
+from .. import __version__
+
+class DummyConfigMixin(ConfigMixin):
+    config_name = "config.json"
+
+    def __init__(self, **kwargs):
+        self.register_to_config(**kwargs)
+
+def test_to_json_string_with_config():
+    # Load the YAML config file
+    config_path = os.path.join(os.path.dirname(__file__), "..", "configs", "base_wan_14b.yml")
+
+    # Initialize pyconfig with the YAML config
+    pyconfig.initialize([None, config_path])
+    config = pyconfig.config
+
+    # Create a DummyConfigMixin instance
+    dummy_config = DummyConfigMixin(**config.get_keys())
+
+    # Get the JSON string
+    json_string = dummy_config.to_json_string()
+
+    # Parse the JSON string
+    parsed_json = json.loads(json_string)
+
+    # Assertions
+    assert parsed_json["_class_name"] == "DummyConfigMixin"
+    assert parsed_json["_diffusers_version"] == __version__
+
+    # Check a few values from the config
+    assert parsed_json["run_name"] == config.run_name
+    assert parsed_json["pretrained_model_name_or_path"] == config.pretrained_model_name_or_path
+    assert parsed_json["flash_block_sizes"]["block_q"] == config.flash_block_sizes["block_q"]
+
+    # The following keys are explicitly removed in to_json_string, so we assert they are not present
+    assert "weights_dtype" not in parsed_json
+    assert "precision" not in parsed_json