1 files changed, 22 insertions, 0 deletions
diff --git a/test/background/reducers/tab.test.js b/test/background/reducers/tab.test.js
new file mode 100644
index 0000000..09fa8a7
--- /dev/null
+++ b/test/background/reducers/tab.test.js
@@ -0,0 +1,22 @@
+import actions from 'background/actions';
+import tabReducer from 'background/reducers/tab';
+
+describe("tab reducer", () => {
+  it('return the initial state', () => {
+    let state = tabReducer(undefined, {});
+    expect(state.previousSelected).to.equal(-1);
+    expect(state.currentSelected).to.equal(-1);
+  });
+
+  it('return next state for TAB_SELECTED', () => {
+    let state = undefined;
+
+    state = tabReducer(state, { type: actions.TAB_SELECTED, tabId: 123 });
+    expect(state.previousSelected).to.equal(-1);
+    expect(state.currentSelected).to.equal(123);
+
+    state = tabReducer(state, { type: actions.TAB_SELECTED, tabId: 456 });
+    expect(state.previousSelected).to.equal(123);
+    expect(state.currentSelected).to.equal(456);
+  });
+});