Respect sliding_window=None (#1214)

src/axolotl/monkeypatch/mistral_attn_hijack_flash.py

@@ -94,7 +94,7 @@ def _prepare_decoder_attention_mask(
     sliding_window,
 ):  # pylint: disable=unused-argument
     # [bsz, seq_len]
-    if attention_mask is None:
+    if attention_mask is None or sliding_window is None:
         return attention_mask
 
     # NOTE: attention mask and sliding masks are only broadcastable in certain scenarios.
@@ -151,7 +151,7 @@ def flashattn_forward(
     )
 
     use_sliding_windows = (
-        hasattr(self.config, "sliding_window") is not None
+        getattr(self.config, "sliding_window") is not None
         and kv_seq_len > self.config.sliding_window
     )