运行测试时，Jest无法处理TypeScript TSX文件

Question

Running tests using Jest with TypeScript TSX occurs in errors.

I have the following base set up:

https://github.com/joe-glasgow/tsx-jest-unit

However when running

yarn run test

the following error occurs:

const checkbox = ReactTestUtils.renderIntoDocument(labelOn, "On", labelOff = "Off" /  >
                                                                                      ^
SyntaxError: Unexpected token >

I was under the impression, that by using the preprocessor that TSX would be handled correctly?

Thanks in advance.

Answer 1

After cloning the repo to have a look, it turns out the code is fine, but there's a weird formatting issue. Here's a git diff showing my changes (or lack of) and the test passing. I added a new line at the end of the file and that's it.

As for the cause, I'm not really sure. It could be something to do with line endings, a problem with the preprocessor, a problem with your editor etc, it's hard to tell! Anyway, I hope this helps.

[

Answer 2

After some digging around and trying out various configurations, "transformIgnorePatterns" to the jest configuration package.json solved the issue:

"jest" : {
        "transformIgnorePatterns": [
            "node_modules/"
        ],
        ...
}

Go figure!