Merge pull request #5 from matthewrfindley/handle-null-values

Handle freezing with null values

lib/freeze.js

@@ -1,4 +1,6 @@
 function isFreezable(obj) {
+  if (obj === null) return false;
+
   return Array.isArray(obj) ||
     typeof obj === 'object';
 }

test/freeze.js

@@ -50,4 +50,10 @@ describe('freeze', () => {
 
     expect(Object.isFrozen(obj)).to.be.false;
   });
+
+  it('handles null objects', () => {
+    const obj = { foo: null };
+    freeze(obj);
+    expect(Object.isFrozen(obj)).to.be.true;
+  });
 });