Upgrading mocha 8 to 9

Breaking8.4.0 → 9.2.2Breaking4Platform1New5Fixed13Other11

BreakingUpgrade verdict

4 breaking changes and a platform requirement change.

In plain terms

Remove deprecated utils.lookupFiles() (@juergba).
Limit the size of actual/expected for diff generation (@juergba).
Refactoring: Consuming log-symbols alternate to code for win32 in reporters/base (@MoonSupport).
import-first loading of test files (@giltayar).

Must act Top 4 of 5 that need code or config changes

Node.js requirement changed in 9.0.0: >= 10.12.0 → >= 12.0.0.

Drops wide-align.

Installs 80 packages in all (was 91).