test: ensure empty options are working (#810)

Author: evilebottnawi

test/__snapshots__/loader.test.js.snap

@@ -390,6 +390,32 @@ exports.push([module.id, \\"\\", \\"\\"]);
 
 exports[`loader should compile with empty css entry point: warnings 1`] = `Array []`;
 
+exports[`loader should compile with empty options: errors 1`] = `Array []`;
+
+exports[`loader should compile with empty options: module (evaluated) 1`] = `
+Array [
+  Array [
+    1,
+    "",
+    "",
+  ],
+]
+`;
+
+exports[`loader should compile with empty options: module 1`] = `
+"exports = module.exports = require(\\"../../lib/runtime/api.js\\")(false);
+// imports
+
+
+// module
+exports.push([module.id, \\"\\", \\"\\"]);
+
+// exports
+"
+`;
+
+exports[`loader should compile with empty options: warnings 1`] = `Array []`;
+
 exports[`loader should throw error on invalid css syntax: errors 1`] = `
 Array [
   "ModuleBuildError: Module build failed (from \`replaced original path\`):

test/loader.test.js

@@ -47,6 +47,21 @@ describe('loader', () => {
     expect(stats.compilation.errors).toMatchSnapshot('errors');
   });
 
+  it('should compile with empty options', async () => {
+    const config = { loader: { options: {} } };
+    const testId = './empty.css';
+    const stats = await webpack(testId, config);
+    const { modules } = stats.toJson();
+    const module = modules.find((m) => m.id === testId);
+
+    expect(module.source).toMatchSnapshot('module');
+    expect(evaluated(module.source, modules)).toMatchSnapshot(
+      'module (evaluated)'
+    );
+    expect(stats.compilation.warnings).toMatchSnapshot('warnings');
+    expect(stats.compilation.errors).toMatchSnapshot('errors');
+  });
+
   it('should throws error when no loader for assets', async () => {
     const config = {
       rules: [