list, operations validation in constructor

carlosrberto · Apr 2, 2018 · 2693acb · 2693acb
1 parent 35aed17
commit 2693acb
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Showing 2 changed files with 25 additions and 1 deletion.
diff --git a/src/LazyList.js b/src/LazyList.js
@@ -10,6 +10,14 @@ export const VALID_OPERATIONS = Object
 
 export default class LazyList {
   constructor(list, operations = []) {
+    if (!Array.isArray(list)) {
+      throw Error('Invalid list argument');
+    }
+
+    if (!Array.isArray(operations)) {
+      throw Error('Invalid operations argument');
+    }
+
     this.operations = operations;
     this.list = list;
   }

diff --git a/src/LazyList.test.js b/src/LazyList.test.js
@@ -1,5 +1,21 @@
 import lazy from './index';
-import { LIST_OPERATIONS } from './LazyList';
+import LazyList, { LIST_OPERATIONS } from './LazyList';
+
+describe('LazyList.constructor', () => {
+  it('should throw when invalid list is provided', () => {
+    expect(() => {
+      const list = () => new LazyList(null);
+      list();
+    }).toThrowError('Invalid list argument');
+  });
+
+  it('should throw when invalid operations is provided', () => {
+    expect(() => {
+      const list = () => new LazyList([], null);
+      list();
+    }).toThrowError('Invalid operations argument');
+  });
+});
 
 describe('LazyList.createOperation', () => {
   it('should throw when invalid operation is provided', () => {