Unable to install cart_checkout_validation on Shopify CLI

[vincedenis]

When I do yarn ``` shopify app generate extension --name my-extension ```

I receive a prompt to choose language and when I select either JS or TS, this error below appears.

yarn add @Shopify/shopify_function@0.1.0 javy@0.1.1 --prod
Unknown Syntax Error: Command not found; did you mean one of:

0. yarn add [--json] [-F,--fixed] [-E,--exact] [-T,--tilde] [-C,--caret] [-D,--dev] [-P,--peer] [-O,--optional] [--prefer-dev]
[-i,--interactive] [--cached] [--mode #0] ...
1. yarn add [--json] [-F,--fixed] [-E,--exact] [-T,--tilde] [-C,--caret] [-D,--dev] [-P,--peer] [-O,--optional] [--prefer-dev]
[-i,--interactive] [--cached] [--mode #0] ...
2. yarn add [--json] [-F,--fixed] [-E,--exact] [-T,--tilde] [-C,--caret] [-D,--dev] [-P,--peer] [-O,--optional] [--prefer-dev]
[-i,--interactive] [--cached] [--mode #0] ...

While running add @Shopify/shopify_function@0.1.0 javy@0.1.1 --prod

How can I fix this?

[SBD_]

Hey @vincedenis 

Try:

```

npm run shopify app generate extension -- --name my-extension

```

[dylanpierce]

This error is happening for us as well, even with only specifying the extension name.

We're using:

```

npx shopify app generate extension --name my-validation-extension

```

[SBD_]

Hey @dylanpierce 

Can you try updating `@shopify/cli` / which version is specified in your package.json?