My reading of this is that the examination was a subset of the full set they manually examined.
From the source:
> It’s so compelling that we at Slack decided to convert more than 15,000 of our frontend unit and integration Enzyme tests to RTL, as part of the update to React 18.
and
> Our benchmark for quality was set by the standards achieved by the frontend developers based on our quality rubric that covers imports, rendering methods, JavaScript/TypeScript logic, and Jest assertions. We aimed to match their level of quality. The evaluation revealed that 80% of the content within these files was accurately converted, while the remaining 20% required manual intervention.
There is a diagram that mentions 22% of the subset of manually inspected files that were 100% converted. But Slack is manually checking all converted test cases anyway so they don't seem to consider this the success rate.
From the source:
> It’s so compelling that we at Slack decided to convert more than 15,000 of our frontend unit and integration Enzyme tests to RTL, as part of the update to React 18.
and
> Our benchmark for quality was set by the standards achieved by the frontend developers based on our quality rubric that covers imports, rendering methods, JavaScript/TypeScript logic, and Jest assertions. We aimed to match their level of quality. The evaluation revealed that 80% of the content within these files was accurately converted, while the remaining 20% required manual intervention.
There is a diagram that mentions 22% of the subset of manually inspected files that were 100% converted. But Slack is manually checking all converted test cases anyway so they don't seem to consider this the success rate.
https://slack.engineering/balancing-old-tricks-with-new-feat...