added checks for layers to transforms and layer pattern lora

src/peft/tuners/lora/config.py

@@ -338,6 +338,13 @@ def __post_init__(self):
         self.exclude_modules = (
             set(self.exclude_modules) if isinstance(self.exclude_modules, list) else self.exclude_modules
         )
+
+        # check for layers_to_transform and layers_pattern
+        if self.layers_to_transform is not None and self.layers_pattern is None:
+            raise ValueError(
+                "When `layers_to_transform` is specified, `layers_pattern` must also be specified. "
+            )
+
         # if target_modules is a regex expression, then layers_to_transform should be None
         if isinstance(self.target_modules, str) and self.layers_to_transform is not None:
             raise ValueError("`layers_to_transform` cannot be used when `target_modules` is a str.")