Running older versions of npm with execa prevents retriving installable commands as JSON

Bug

When using older versions of npm such as 3.5.2 (this is what you get when you install nodejs with Ubuntu by default), execa will fail to get the JSON response as intended when passing in the search command with necessary arguments.

screenshot_20180815_115024

From reasoning this seems to be because the --json argument is being ignored which causes it to fail.

Code

Try:

const execa = require("execa");

async function test() {
    console.log( 
        await execa('npm', ['search', '@dojo', 'cli-', '--json',  '--searchstaleness=0'])
    );
}

test();

Using a older version of NPM.

Expected behavior:

JSON response that doesn't throw an error in the dojo cli search function.

Actual behavior:

Invalid response from npm search

dojo / cli

Running older versions of npm with execa prevents retriving installable commands as JSON #251