test: migrate old-snyk-format to jest

test/jest/unit/old-snyk-format.spec.ts

@@ -0,0 +1,18 @@
+import * as policy from 'snyk-policy';
+import { loadJson } from '../../utils';
+import * as path from 'path';
+
+it('test sensibly bails if gets an old .snyk format', async () => {
+  const vulns2 = loadJson(
+    path.resolve(__dirname, '../../fixtures/test-jsbin-vulns-updated.json'),
+  );
+  try {
+    const config = await policy.load(
+      path.resolve(__dirname, '../../fixtures/old-snyk-config'),
+    );
+    const res = await config.filter(vulns2);
+    fail('was expecting an error, got ' + JSON.stringify(res));
+  } catch (e) {
+    expect(e.code).toEqual('OLD_DOTFILE_FORMAT');
+  }
+});