create react app (cra) jest and npm link (symlinks)

npm-link.md

# setup code
mkdir ~/tmp
cd ~/tmp
npx create-react-app my-app
cd my-app

# confirm tests pass
CI=true npm run test -- --no-cache

# move package
mv ~/tmp/my-app/node_modules/react-dom ~/tmp

# use npm link
npm link ../react-dom

# rerun tests
CI=true npm run test -- --no-cache

Tests fail with error:

FAIL src/App.test.js
  ● Test suite failed to run

    Cannot find module 'react' from 'react-dom.development.js'

      16 | 'use strict';
      17 |
    > 18 | var React = require('react');
         |             ^
      19 | var _assign = require('object-assign');
      20 | var checkPropTypes = require('prop-types/checkPropTypes');
      21 | var scheduler = require('scheduler');

      at Resolver.resolveModule (node_modules/jest-resolve/build/index.js:221:17)
      at require (../react-dom/cjs/react-dom.development.js:18:13)
      at Object.<anonymous> (../react-dom/cjs/react-dom.development.js:15:3)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        2.722s
Ran all test suites.

symlink.md

# setup code
mkdir ~/tmp
cd ~/tmp
npx create-react-app my-app
cd my-app

# confirm tests pass
CI=true npm run test -- --no-cache

# move package
mv ~/tmp/my-app/node_modules/react-dom ~/tmp

# create symlink
ln -s ~/tmp/react-dom ~/tmp/my-app/node_modules

# rerun tests
CI=true npm run test -- --no-cache

Tests fail with error:

FAIL src/App.test.js
  ● Test suite failed to run

    Cannot find module 'react' from 'react-dom.development.js'

      16 | 'use strict';
      17 |
    > 18 | var React = require('react');
         |             ^
      19 | var _assign = require('object-assign');
      20 | var checkPropTypes = require('prop-types/checkPropTypes');
      21 | var scheduler = require('scheduler');

      at Resolver.resolveModule (node_modules/jest-resolve/build/index.js:221:17)
      at require (../react-dom/cjs/react-dom.development.js:18:13)
      at Object.<anonymous> (../react-dom/cjs/react-dom.development.js:15:3)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        2.722s
Ran all test suites.