Path problem with npm test contributing a pull request on Windows

I’m trying to create a Pull Request

I forked and cloned but when I run npm test in the root I get

lerna info Executing command in 24 packages: "npm run test:ci"
babel-plugin-frontity: > babel-plugin-frontity@1.0.4 test:ci D:\work\bitbucket\learn\frontity\frontity\packages\babel-plugin-frontity
babel-plugin-frontity: > ../../node_modules/.bin/jest --ci
babel-plugin-frontity: '..' is not recognized as an internal or external command

currently using nvm 10.24.1 (64 bit) on Windows 10 in VS Code Git Bash

also note the contribution docs are out of date. There is no longer an examples\mars-theme-test folder. It appears to be projects\mars-theme ?

thanks for any suggestions
J

Update: tests seems to run okay under WSL (ie using Linux paths), so I assume it’s a / separator issue when using Windows paths