diff --git a/test/index.js b/test/index.js
index 5fd9dec..f6aa40f 100644
--- a/test/index.js
+++ b/test/index.js
@@ -93,4 +93,29 @@ test('functions', () => {
 	assert.is(fn(foo, 'hello', [[fn], 'world']), 'hello world');
 });
 
+test('arrays (nested with falsy)', () => {
+	assert.is(fn(['foo', [null, [undefined, [false, [0, ['']]]]]]), 'foo');
+	assert.is(fn(['foo', [null, 'bar', [undefined, false, ['baz', 0, '']]]]), 'foo bar baz');
+});
+
+test('symbols', () => {
+	assert.is(fn(Symbol('foo')), '');
+	assert.is(fn(Symbol('foo'), Symbol('bar')), '');
+	assert.is(fn('foo', Symbol('bar'), 'baz'), 'foo baz');
+	assert.is(fn(['foo', Symbol('bar'), 'baz']), 'foo baz');
+	assert.is(fn({ [Symbol('foo')]: true }), '');
+});
+
+test('objects (inherited keys)', () => {
+	const parent = { inherited: true };
+	const child = Object.create(parent);
+	child.own = true;
+	assert.is(fn(child), 'own inherited');
+
+	const parentFalsy = { inherited: false };
+	const childTruthy = Object.create(parentFalsy);
+	childTruthy.own = true;
+	assert.is(fn(childTruthy), 'own');
+});
+
 test.run();