# Notes on ava 4

ava 4 is usable only with ES modules. If you want to run test of a commonjs
module, you can use tape (preferred) or jest.

## Using tape

To use tape instead of ava, you have to patch test. Some tips:
 * replace `import test from 'ava'` by `import test from 'tape'`
   (or by `const test = require('tape')` if your module isn't ES)
 * add a `t.end()` at the end of each test
 * translate each test files into commonjs if module isn't `type:module`
 * replace all:
   * `t.truthy` by `t.ok`
   * `t.falsy` by `t.nok`
   * `t.notThrows` by `t.doesNotThrow`
   * `t.regex(string, /regex/)` by `t.ok(string.match(/regex/))`
 * drop tests that uses `t.notThrowsAsync` or `t.throwsAsync`

If your module is a ES module, you may have to link tape for test:

```shell
$ cat >> debian/nodejs/extlinks << EOF
tape	test
EOF
```

## Using jest

You can transform a ava test file into a jest one using `npx jest-codemods`.
Then you have to answer to some questions:
 * **Which parser do you want to use?**                          : choose babel
 * **Which test library would you like to migrate from?**        : choose ava
 * **Are you using the global object for assertions**            : choose no
 * **Will you be using Jest on Node.js as your test runner?**    : choose yes
 * **On which files or directory should the codemods be applied?**: enter the
   good directory (test for example)

Then you may have to add a `babel.config.json` file if you encounter errors
like `Jest encountered an unexpected token`:

```shell
$ cat > babel.config.json << EOF
{"presets":["@babel/preset-env"],"plugins":["@babel/plugin-transform-runtime"]}
EOF
```

Then you'll probably have things to fix...