cd sample-component-library && npm i && npm run build && npm pack
cd ../sample-component-library-react && npm i && npm i ${WORKING_DIR}/sample-component-library/sample-component-library-0.0.1.tgz && npm run build && npm pack
cd ../sample-app && npm i && npm i ${WORKING_DIR}/sample-component-library-react/component-library-react-0.0.1.tgz && npm run test

Downgrading to @stencil/core@2.14.0 will prevent PrettyFormatPluginError: Invalid string length. To reproduce the happy path, manually modify the package.json in sample-component-library to @stencil/core: "2.14.0, delete the dist folders and rerun the above steps