swarm-ui: start page setup assistant offers to create ruth

frontend/packages/swarm-ui/test/ruth-missing.test.mjs

@@ -0,0 +1,37 @@
+// The setup assistant's "is ruth missing" check. Run by `npm test`.
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import { ruthIsMissing } from "../src/shell/ruth-missing.ts";
+
+const answering =
+  (body, ok = true) =>
+  async () => ({
+    ok,
+    json: async () => body,
+  });
+
+test("a roster without ruth means ruth is missing", async () => {
+  assert.equal(
+    await ruthIsMissing(answering([{ name: "atlas" }, { name: "argus" }])),
+    true,
+  );
+  assert.equal(await ruthIsMissing(answering([])), true);
+});
+
+test("a roster with ruth means she is not missing", async () => {
+  assert.equal(
+    await ruthIsMissing(answering([{ name: "atlas" }, { name: "ruth" }])),
+    false,
+  );
+});
+
+test("anything but a clear answer is not missing", async () => {
+  assert.equal(await ruthIsMissing(answering([], false)), false);
+  assert.equal(await ruthIsMissing(answering({ not: "a list" })), false);
+  assert.equal(
+    await ruthIsMissing(async () => {
+      throw new Error("offline");
+    }),
+    false,
+  );
+});