update empty options validation check

Author: manwaring

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "serverless-prune-versions",
-  "version": "0.1.10",
+  "version": "0.1.11",
   "description": "Serverless plugin to delete old versions of deployed functions from AWS",
   "scripts": {
     "build": "rimraf dist && tsc -p tsconfig.build.json",

package.json

@@ -4,6 +4,8 @@ export const defaultOptions: Serverless.Options = {
   number: '5'
 };
 
+export const emptyOptions = {};
+
 export const invalidOptions = {
   number: '0'
 };

src/mock-data/options.ts

@@ -1,7 +1,7 @@
 import { PrunePlugin } from './plugin';
 import { LOG_PREFIX } from './log';
 import { getServerless, getServerlessWithFunctions } from './mock-data/serverless';
-import { defaultOptions, invalidOptions, dryRunOptions, noDeployOptions } from './mock-data/options';
+import { defaultOptions, invalidOptions, dryRunOptions, noDeployOptions, emptyOptions } from './mock-data/options';
 import { invalidConfig, disabledConfig } from './mock-data/config';
 
 describe('Prune plugin', () => {
@@ -27,6 +27,11 @@ describe('Prune plugin', () => {
       // @ts-ignore
       expect(() => new PrunePlugin(mockInvalidServerless)).toThrow();
     });
+
+    it('Instantiates with empty default options', () => {
+      const mockServerless = getServerless();
+      new PrunePlugin(mockServerless, emptyOptions);
+    });
   });
 
   describe('Post deploy pruning', () => {

src/plugin.test.ts

@@ -29,7 +29,7 @@ export class Settings implements PruneSettings {
   }
 
   private cleanRawOptions(rawOptions?: Serverless.Options): PruneSettings {
-    if (rawOptions) {
+    if (rawOptions && Object.keys(rawOptions).length > 0) {
       const replacementKeys = { n: 'number', d: 'dryRun', i: 'includeLayers' };
       const replacedOptions = Object.keys(rawOptions).map(key => {
         const newKey = replacementKeys[key] || key;