fix: feuille xlsx vide editable avec quadrillage vierge BUG-094

tests/test_xlsx_viewer.py

@@ -96,6 +96,29 @@ class TestXlsxDisplay:
         resp = client.get(f"/api/file/{VAULT}", params={"path": "corrupt.xlsx"})
         assert resp.status_code == 500
 
+    def test_empty_sheet_renders_an_editable_blank_grid(self, client, test_vault_dir):
+        """BUG-094 — a blank sheet used to render as a bare « Feuille vide »
+        paragraph with no cell, so a freshly added sheet could not be filled
+        and had no way to insert a row/column. It now exposes a small editable
+        grid with real A1 coordinates."""
+        from openpyxl import Workbook
+
+        path = Path(test_vault_dir) / "blank.xlsx"
+        wb = Workbook()
+        wb.active.title = "Vide"
+        wb.create_sheet("Vide2")
+        wb.save(str(path))
+
+        resp = client.get(f"/api/file/{VAULT}", params={"path": "blank.xlsx"})
+        assert resp.status_code == 200
+        vide = next(s for s in resp.json()["xlsx_sheets"] if s["name"] == "Vide")
+        assert "Feuille vide" not in vide["html"]
+        assert 'data-cell="A1"' in vide["html"]
+        assert 'data-cell="H20"' in vide["html"]  # last cell of the blank grid
+        assert vide["rows"] == 20
+        assert vide["cols"] == 8
+        assert vide["truncated"] is False
+
 
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