Update test to load from HF Hub

test/test_invariants.py

@@ -2,12 +2,13 @@
 Invariant tests for cterdam/iso_3166-2 dataset.
 
 Run from dataset root after cloning:
+    pip install datasets pytest
     pytest test/test_invariants.py -v
 
 Verifies:
 - name field matches lang selection (name_en/ru/zh)
 - hash = SHA256(name)
-- lang matches parent region's language rule
+- lang matches region-based language rule
 - hash format is 64-char hex string
 """
 
@@ -25,11 +26,11 @@ SINOPHONE_REGIONS = {
 }
 
 
-def determine_expected_lang(region: str) -> str:
-    """Determine expected lang from parent region code."""
-    if region in SINOPHONE_REGIONS:
+def determine_expected_lang(region_code: str) -> str:
+    """Determine expected lang from region code."""
+    if region_code in SINOPHONE_REGIONS:
         return 'zh'
-    elif region in SLAVIC_REGIONS:
+    elif region_code in SLAVIC_REGIONS:
         return 'ru'
     else:
         return 'en'
@@ -37,7 +38,8 @@ def determine_expected_lang(region: str) -> str:
 
 @pytest.fixture(scope="session")
 def dataset():
-    return load_dataset('.', split='train')
+    """Load dataset from HF Hub."""
+    return load_dataset('cterdam/iso_3166-2', split='train')
 
 
 def test_lang_values_valid(dataset):
@@ -113,4 +115,5 @@ def test_lang_matches_parent_region(dataset):
             if len(mismatches) >= 5:
                 break
     
-    assert mismatches == [], f"Lang mismatches: {mismatches}"
+    assert mismatches == [], f"Lang mismatches: {{mismatches}}"
+