swarm-ui: ignore a saved table filter whose column is gone

frontend/packages/swarm-ui/test/table-filters.test.mjs

@@ -0,0 +1,19 @@
+// Which remembered table filters still apply. Run by `npm test`, which Node
+// runs with its built-in test runner and type stripping, so the `.ts` module
+// is imported as it is.
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import { forExistingColumns } from "../src/ui/table/table-filters.ts";
+
+test("a filter on a column that is gone is ignored", () => {
+  const saved = { status: { value: "up" }, oldName: { value: "x" } };
+  assert.deepEqual(forExistingColumns(saved, ["status", "name"]), {
+    status: { value: "up" },
+  });
+});
+
+test("filters on columns that all exist are kept, and none is fine", () => {
+  const saved = { a: 1, b: 2 };
+  assert.deepEqual(forExistingColumns(saved, ["a", "b"]), saved);
+  assert.deepEqual(forExistingColumns({}, ["a"]), {});
+});