Support TypeScript support and plugin files

[amirrustam]

Current behavior:

TypeScript support files (i.e support/commands.ts) and plugin file (plugins/index.ts) cause tasks and/or custom commands to not be found/registered. For example, the custom task db:seed could not be registered within the cypress-realworld-app project:

Converting the plugins file back to JavaScript resolved the issue, but a similar issue also exists for a commands.ts, which resulted in custom commands not being added:

Converting the support files back to JavaScript also resolved the issue.

It should be noted that this issue did not exist with Cypress develop branch before and after the v4.6 release.

Desired behavior:

• TypeScript support and plugin files to be properly loaded and/or executed for test execution.
• Customs commands should be added and tasks should be registered when declared in TS files.

Test code to reproduce

Reproduction (with associated commit) can be seen within this cypress-realworld-app test run: https://dashboard.cypress.io/projects/7s5okt/runs/1272/specs

Versions

Cypress v4.6

[bahmutov]

Confirmed in https://github.com/bahmutov/test-ts-plugins

Workaround: point at plugins and support TS files explicitly from cypress.json file

{
  "pluginsFile": "cypress/plugins/index.ts",
  "supportFile": "cypress/support/index.ts"
}

[amirrustam]

@bahmutov I can confirm your workaround worked.

[cypress-bot]

The code for this is done in cypress-io/cypress#7463, but has yet to be released.
We'll update this issue and reference the changelog when it's released.

[cypress-bot]

Released in 4.8.0.

This comment thread has been locked. If you are still experiencing this issue after upgrading to
Cypress v4.8.0, please open a new issue.