test(exports): add failing resolution tests for ep_etherpad-lite subpaths

Exercises the require + import conditions for the subpaths plugins
consume. Will pass once src/package.json gets an exports map.

Author: SamTV12345

src/tests/backend/specs/exports_map.ts

@@ -0,0 +1,46 @@
+import { describe, expect, test } from 'vitest';
+import { createRequire } from 'node:module';
+
+const require = createRequire(import.meta.url);
+
+const cjsSubpaths = [
+  'ep_etherpad-lite/node/eejs',
+  'ep_etherpad-lite/node/db/PadManager',
+  'ep_etherpad-lite/node/db/API.js',
+  'ep_etherpad-lite/node/db/AuthorManager',
+  'ep_etherpad-lite/static/js/pad_utils',
+  'ep_etherpad-lite/tests/backend/common',
+];
+
+const esmSubpaths = [
+  'ep_etherpad-lite/node/eejs/index.js',
+  'ep_etherpad-lite/node/db/PadManager.js',
+  'ep_etherpad-lite/node/db/API.js',
+  'ep_etherpad-lite/static/js/pad_utils.js',
+];
+
+describe('ep_etherpad-lite exports map', () => {
+  describe('require() condition (CJS plugins)', () => {
+    for (const spec of cjsSubpaths) {
+      test(`require('${spec}') resolves`, () => {
+        const resolved = require.resolve(spec);
+        expect(resolved).toMatch(/\.cjs$/);
+      });
+
+      test(`require('${spec}') loads a module`, () => {
+        const mod = require(spec);
+        expect(mod).toBeTruthy();
+        expect(typeof mod).toBe('object');
+      });
+    }
+  });
+
+  describe('import() condition (ESM plugins)', () => {
+    for (const spec of esmSubpaths) {
+      test(`import('${spec}') resolves to a .js file`, async () => {
+        const mod = await import(spec);
+        expect(mod).toBeTruthy();
+      });
+    }
+  });
+});