There is no “100% coverage” in Automated E2E Software Testing

It is simply not possible and neither necessary.

It is well accepted that 100% test coverage (functional, not unit testing) from manual testing is not possible. However, some had unrealistic expectations of 100% coverage in E2E Test Automation. This is very wrong, this article will explain why.

“It is neither possible or necessary to achieve 100% coverage in software testing” — Zhimin Zhan

Table of Contents:
· 100% Test Coverage is simply Not Possible
· Test Execution Time?

100% Test Coverage is simply Not Possible

First of all, people saying 100% test coverage don’t understand test automation or software testing.

At a conference talk, I said, “I can easily come up with hundreds of automated test scenarios for a credit card payment user story, just on the single payment page”. Below is a partial list:

• Can pay the full amount with Visa Credit Card
• Incomplete credit card info (mandatory check), e.g. no CSC, CC number, Expiry Date, …
• Credit card info not matching, e.g. wrong CSC, card number does not match type