add warning if DuplicateDetector is used

pylintrc

@@ -1,2 +1,2 @@
 [MESSAGES CONTROL]
-disable = too-few-public-methods
+disable = too-few-public-methods,cyclic-import

smart_importer/detector.py

@@ -1,8 +1,12 @@
 """Duplicate detector hook."""
 
+from __future__ import annotations
+
 import logging
+from typing import Callable
 
-from beangulp import similar
+from beancount.core import data
+from beangulp import Importer, similar
 
 from smart_importer.hooks import ImporterHook
 
@@ -18,12 +22,23 @@ class DuplicateDetector(ImporterHook):
         entries to classify against.
     """
 
-    def __init__(self, comparator=None, window_days=2):
+    def __init__(
+        self,
+        comparator: Callable[[data.Directive, data.Directive], bool]
+        | None = None,
+        window_days: int = 2,
+    ) -> None:
         super().__init__()
         self.comparator = comparator
         self.window_days = window_days
 
-    def __call__(self, importer, file, imported_entries, existing):
+    def __call__(
+        self,
+        importer: Importer,
+        file: str,
+        imported_entries: data.Directives,
+        existing: data.Directives,
+    ) -> data.Directives:
         """Add duplicate metadata for imported transactions.
 
         Args:

smart_importer/hooks.py

@@ -70,6 +70,15 @@ def patched_extract_method(
 
         return imported_entries
 
-    importer.extract = patched_extract_method
-    importer.deduplicate = lambda entries, existing: None
+    importer.extract = patched_extract_method  # type: ignore
+
+    # pylint: disable=import-outside-toplevel
+    from smart_importer.detector import DuplicateDetector
+
+    if any(isinstance(hook, DuplicateDetector) for hook in hooks):
+        logger.warning(
+            "Use of DuplicateDetector detected - this is deprecated, "
+            "please use the beangulp.Importer.deduplicate method directly."
+        )
+        importer.deduplicate = lambda entries, existing: None  # type: ignore
     return importer