From 365b44aff5f7823d9f47020fbc0a070b80db7361 Mon Sep 17 00:00:00 2001
From: Ben McKernan <ben-mckernan@users.noreply.github.com>
Date: Fri, 22 Feb 2019 14:19:03 +0100
Subject: [PATCH] fix(tab): Set initial tabIndex state to -1 (#690)

---
 packages/tab/index.tsx       |  1 +
 test/unit/tab/index.test.tsx | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/packages/tab/index.tsx b/packages/tab/index.tsx
index 767062dfa..0d63cf797 100644
--- a/packages/tab/index.tsx
+++ b/packages/tab/index.tsx
@@ -72,6 +72,7 @@ export default class Tab extends React.Component<TabProps, TabState> {
     'aria-selected': false,
     'activateIndicator': false,
     'previousIndicatorClientRect': this.props.previousIndicatorClientRect,
+    'tabIndex': -1,
   };
 
   componentDidMount() {
diff --git a/test/unit/tab/index.test.tsx b/test/unit/tab/index.test.tsx
index 6ecfc32c1..5787a66d5 100644
--- a/test/unit/tab/index.test.tsx
+++ b/test/unit/tab/index.test.tsx
@@ -29,6 +29,16 @@ test('adds the active class if props.active is true on mount', () => {
   assert.isTrue(wrapper.hasClass('mdc-tab--active'));
 });
 
+test('sets the tabIndex to 0 if props.active is true on mount', () => {
+  const wrapper = shallow(<Tab active />);
+  assert.equal(wrapper.prop('tabIndex'), 0);
+});
+
+test('sets the tabIndex to -1 if props.active is false on mount', () => {
+  const wrapper = shallow(<Tab active={false} />);
+  assert.equal(wrapper.prop('tabIndex'), -1);
+});
+
 test('adds a class from state.classList', () => {
   const wrapper = shallow(<Tab />);
   wrapper.setState({classList: new Set(['test-class'])});