My D3 bar chart project didn't pass the test

Background:

I finish my D3 bar chart project, I follow the guide of this book: Interactive Data Visualization for the Web, 2nd Edition

Everything goes right, I finished the bar chart, I got the tooltip, However, when I click the test button, it turn out to be failed 8/14 failed.
Here is my project on codepen:
D3 bar chart project

I glance over the code several times, thirty minutes later.I still couldn’t figure out where the problem is.
I’m thrilled for your advice!

I’m not sure I understand the problem. You’ve created a bar chart and it looks appropriate, but it’s a different chart than the one described in the fCC bar chart project and uses different data. It shouldn’t pass the fCC bar chart tests. If you want to use the tests, you really should try to complete the chart on which the tests are based.