test: add pytest coverage for plugin utilities

tests/test_resource_index.py

@@ -0,0 +1,27 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from afs_scawful.resource_index import ResourceIndexer
+
+
+def test_resource_indexer_dedupes(tmp_path: Path) -> None:
+    root = tmp_path / "resources"
+    root.mkdir()
+
+    (root / "a.txt").write_text("same\n", encoding="utf-8")
+    (root / "b.txt").write_text("same\n", encoding="utf-8")
+    (root / "c.md").write_text("diff\n", encoding="utf-8")
+
+    indexer = ResourceIndexer(
+        resource_roots=[root],
+        search_patterns=["**/*.txt", "**/*.md"],
+        exclude_patterns=[],
+        index_path=tmp_path / "index.json",
+    )
+
+    result = indexer.build_index()
+    assert result.total_files == 2
+    assert result.duplicates_found == 1
+    assert result.by_type.get("txt", 0) == 1
+    assert result.by_type.get("md", 0) == 1