fix(documents): refresh library counters after removal (#1924)

tests/test_document_library_delete_counters.py

@@ -0,0 +1,43 @@
+"""Regression for #1809: document library counters must update after delete.
+
+documentLibrary.js is a browser module with several DOM-only imports, so this
+guards the relevant wiring at the source level. A single-card delete used to
+remove the card and decrement `_libraryTotal`, but the header/chips render from
+`_libraryLanguages`, which stayed stale until a full library refetch.
+"""
+
+from pathlib import Path
+
+
+SRC = Path(__file__).resolve().parent.parent / "static/js/documentLibrary.js"
+
+
+def _src() -> str:
+    return SRC.read_text(encoding="utf-8")
+
+
+def _between(text: str, start: str, end: str) -> str:
+    begin = text.index(start)
+    finish = text.index(end, begin)
+    return text[begin:finish]
+
+
+def test_single_delete_updates_language_counters_and_chips():
+    text = _src()
+
+    helper = _between(
+        text,
+        "function libraryRemoveDocumentFromState(docId)",
+        "function libraryRenderGrid()",
+    )
+    assert "_libraryLanguages[lang]" in helper
+    assert "delete _libraryLanguages[lang]" in helper
+    assert "libraryRenderStats();" in helper
+    assert "libraryRenderLangChips();" in helper
+
+    delete_body = _between(
+        text,
+        "async function libraryDeleteSingle(docId, card)",
+        "async function libraryBulkDelete()",
+    )
+    assert "libraryRemoveDocumentFromState(docId);" in delete_body