Fix issue with cache hits

src/ragas/cache.py

@@ -148,9 +148,6 @@ def _make_hashable(o):
 
 
 def _generate_cache_key(func, args, kwargs):
-    if inspect.ismethod(func):
-        args = args[1:]
-
     filtered_kwargs = {k: v for k, v in kwargs.items() if k not in EXCLUDE_KEYS}
 
     key_data = {

tests/unit/test_cache.py

@@ -40,6 +40,24 @@ def sample_func(a, b):
     assert key1 != key3, "Cache keys should differ if kwargs differ"
 
 
+def test_generate_cache_key_bound_method():
+    """Test that cache keys stay the same, when caching bound methods of different objects."""
+
+    class Clazz():
+        def __init__(self, irrelevant):
+            self.irrelevant = irrelevant
+
+        def sample_func(self, a, b):
+            return a + b
+
+    object = Clazz(irrelevant=1)
+    object2 = Clazz(irrelevant=2)
+
+    key1 = _generate_cache_key(object.sample_func, (1, 2), {})
+    key2 = _generate_cache_key(object2.sample_func, (1, 2), {})
+    assert key1 == key2, "Cache keys should match even if the originating objects the methods are bound to are not the same, as long as the arguments match"
+
+
 def test_no_cache_backend():
     """Test that if no cache backend is provided, results are not cached."""
     call_count = {"count": 0}