diff --git a/frontend/src/lib/components/datatableUsableRoles.test.ts b/frontend/src/lib/components/datatableUsableRoles.test.ts
new file mode 100644
index 0000000000..cca4ab7607
--- /dev/null
+++ b/frontend/src/lib/components/datatableUsableRoles.test.ts
@@ -0,0 +1,29 @@
+import { describe, expect, it, vi } from 'vitest'
+
+const request = vi.fn()
+vi.mock('$lib/gen/core/request', () => ({ request: (...args: unknown[]) => request(...args) }))
+vi.mock('$lib/gen', () => ({ OpenAPI: {} }))
+vi.mock('$lib/cloud', () => ({ isCloudHosted: () => false }))
+
+import { listUsableDatatableRoles } from './datatableUsableRoles'
+
+const refuse = (body: string) => () =>
+	Promise.reject(Object.assign(new Error('Bad Request'), { body }))
+
+describe('listUsableDatatableRoles', () => {
+	// The refusal is recognised by its sentence, so rewording it on one side alone would turn every
+	// data table on a build without the Enterprise Edition into a failed lookup rather than one
+	// that is not under roles.
+	it('reads the enterprise refusal as not under roles, and rethrows anything else', async () => {
+		request.mockImplementation(refuse('Data table roles are a Windmill Enterprise Edition feature'))
+		expect(await listUsableDatatableRoles('ws', 'main')).toEqual({
+			permissioned: false,
+			roles: [],
+			default_role: 'admin'
+		})
+
+		request.mockImplementation(refuse('Data table not found'))
+		const rethrown = await listUsableDatatableRoles('ws', 'main').catch((e) => e)
+		expect(rethrown).toBeInstanceOf(Error)
+	})
+})