Throw error if unable to parse Mocha options file

[plroebuck]

Description

The current code silently ignores any problems parsing the options file and continues on.

mocha/bin/options.js

Lines 32 to 47 in 99c2f8a

	try {
	const opts = fs
	.readFileSync(optsPath, 'utf8')
	.replace(/\\\s/g, '%20')
	.split(/\s/)
	.filter(Boolean)
	.map(value => value.replace(/%20/g, ' '));
	process.argv = process.argv
	.slice(0, 2)
	.concat(opts.concat(process.argv.slice(2)));
	} catch (err) {
	// ignore
	}
	process.env.LOADED_MOCHA_OPTS = true;

Code should instead throw an error for any error encountered, except for a nonexistent default options file (i.e., user did not specify --opts and "test/mocha.opts" does not exist).

Downside?

People who have errors in their "mocha.opts" file will experience failures until corrected.

[plroebuck]

NOTE: Ensure this still works when optsPath=/dev/null