fix(jest): Sass require in html

[michaelw85]

Fix error when testing a component that has a require tag with a
sass file.

Closes aurelia/testing#67

[3cp]

There is the other generic jest recommended way. https://jestjs.io/docs/en/webpack#handling-static-assets

If don't want to write the mock module, can use https://github.com/eddyerburgh/jest-transform-stub

[michaelw85]

@huochunpeng Thank you for the info, I will try that proxy setup. If it resolves this issue I will change this PR.

[michaelw85]

@huochunpeng I've looked at the documentation and this setup only works for static content loaded via import statements in your js/ts files. The issue reported describes a flow where a sass file is loaded using a <required from="./style.scss"> tag. This results in aurelia-loader, aurelia-templating-resources (css-resource.js fixupCSSUrls) to handle the file which fails for sass files.

[3cp]

:-)
You should check. It works. https://github.com/huochunpeng/demo-au-jest-scss

Removing ".+\\.scss$": "jest-transform-stub" from package.json will make it fail.

Even with <require> in html, in jest testing, aurelia-loader-nodejs will use nodejs to load the resource anyway.

[michaelw85]

Thank you for the example, I will give it another try. I think I missed the transform entry in the config :/

[michaelw85]

@huochunpeng I can confirm installing jest-transform-stub and adding it as a custom transform entry there is no need for the change in this PR. Do you think we should/could provide this solution out of the box in aurelia cli?

[3cp]

Do you think we should/could provide this solution out of the box in aurelia cli?

Absolutely. Let’s get it in after the big refactoring PR.

[michaelw85]

@huochunpeng ok I will close this PR and create a new one after the big refactor PR is done. Where can I track the status of the PR you are referring to?

[3cp]

#1069

[michaelw85]

Some additional info on stubbing, for me it still fails when adding jest-tranform-stub to the moduleNameMapper. Only adding it to transform seems to work fine (haven't testing imports from TS yet)