terminalWidth appears to be typed incorrectly

[Thenlie]

Description

When using terminalWidth as shown in the docs and invoking it as a function, I get the following error:

TypeError: yargs.terminalWidth is not a function

This error is thrown and my application can not run. If I instead call .wrap(yargs.terminalWidth), the application runs as expected.

Full command

#!/usr/bin/env node

import yargs from 'yargs';
import { hideBin } from 'yargs/helpers';
import { Props, main } from '.';

yargs(hideBin(process.argv))
    .options({
        o: {
            alias: 'outputFile',
            default: 'stdio',
            describe: 'Filename to write response to',
            type: 'string',
        },
        // truncated for brevity
    })
    .command(
        'run',
        'run the CLI tool',
        () => {},
        (argv) => {
            const { outputFile, inputFile, inputPath, useDefault } = argv as unknown as Props;
            main({ outputFile, inputFile, inputPath, useDefault });
        }
    )
    .demandCommand(1)
    .wrap(yargs.terminalWidth()) // <-- ❌ Does not work
    .wrap(yargs.terminalWidth)   // <-- ✅ Works
    .parse();

[shadowspawn]

.terminalWidth() is a method on a yargs instance. It is a bit subtle, but the trick is to make the instance separately from configuring it so that you can call the method.

import yargsFactory from 'yargs/yargs';
import { hideBin } from 'yargs/helpers';

const yargsInstance = yargsFactory(hideBin(process.argv));
yargsInstance.wrap(yargsInstance.terminalWidth());

This is actually covered in the TypeScript usage examples, albeit I think with a typo where myYargs is used instead of yargsInstance.

[Thenlie]

Thanks @shadowspawn for the explanation!