Provide an option to disable test files preprocessing.

• Operating System: Mac
• Cypress Version: 0.19.2
• Browser/Browser Version: Chrome 58

Are you requesting a feature or reporting a bug?

Feature.

Current behavior:

Cypress preprocesses test JavaScript files (using Babel / Browserify). I’d like to use ClojureScript to write tests, which means using a compiler (based on Google Closure) to obtain a final test JS file. However, Google Closure produces JS files that expect this to be set when invoked outside of a function (in the global context). Current Cypress’ preprocessing makes this undefined, which breaks code compiled using Google Closure. I don’t know of any obvious workaround for this.

Expected behavior:

To be able to disable test JS files preprocessing, so that I can use ClojureScript / Google Closure compiler.

How to reproduce the current behavior:

1. Create a ClojureScript test namespace:

(ns st.general)

(js/describe "General" (fn []
  (js/it "Page title" (fn []
    (js/cy.visit "http://localhost:80")
    (.should (js/cy.title) "equal" "Page Title")))))

1. Compile it using ClojureScript compiler to cypress/integration/test.js

2. Run this test using Cypress. It will hang for a long time, and eventually produce an error that can be tracked down to this being unset.

Test code:

n/a

Additional Info (images, notes, stack traces, etc)

This has been briefly discussed on Gitter on June 9th around 1:30 PM UTC.

[brian-mann]

Fixed by https://github.com/cypress-io/cypress/pull/888.

[chrisbreiding]

We’re currently working on a generic plugin system for preprocessing spec files that will solve this issue. You’ll be able to create a plugin that integrates with the Cypress preprocessing pipeline. It will allow you to disable the default preprocessing, or you could create a ClojureScript preprocessor that transpiles your ClojureScript tests and lets the app know to re-run.

This should be released within the next month or so. If it doesn’t make it into 1.0.0, it will be in 1.1.0.