Add support for throwing if failed

[IOAyman]

If verbose: 'throw' is passed in options, an Error is thrown instead of console.erroring to the stdout

[coveralls]

Coverage remained the same at 100.0% when pulling 182505f on IOAyman:patch-option-throw into 8117fc1 on motdotla:master.

[maxbeatty]

I think a better alternative would be to return the error instead of false so consumers can handle the error as they please (throw, report, ignore, etc.)

[IOAyman]

Yeah, it's better than returning false.
How about supporting both approaches? Returning the Error by default, but give the ability to throw if explicitly required via the options.

[maxbeatty]

Please correct me if I'm wrong. The motivation to add an option to throw the error is to control how the error is handled.

Instead of adding options, perhaps it's better to remove one and change what's returned from config. It keeps the footprint and complexity of this module small while allowing the most flexibility for consumers. Taking a page from Hapi's Joi module, we could return an object with an error key that is either null or whatever error occurred and a parsed key with the result of parsing the .env file.

import { config } from 'dotenv'
import variableExpansion from 'dotenv-expand'

env = config()

if (env.error) {
  // handle error as you like
  throw env.error
}

variableExpansion(env.parsed)

This is a low-impact path forward for anyone upgrading major versions. It allows people to continue ignoring errors that are most likely due to a missing file in environments like CI.

• remove verbose option
• change return value of config
• update README
• update CHANGELOG

[coveralls]

Coverage remained the same at 100.0% when pulling 25ffb08 on IOAyman:patch-option-throw into f783543 on motdotla:master.

[maxbeatty]

looks good. will wait for more feedback and review before merging

[jcblw]

This looks good my only concern is with the the return object change and external plugins that do not have dotenv as a dep, eg. dotenv-expand, which has no control if v2 or v3 of dotenv is used.

I do not think there is many of these plugins out there, but I do think it would be a good idea, if this is merged, that we make either PRs or issues to update to support both versions. So that way on release we are not breaking those plugins functionality.

[maxbeatty]

other modules should specify peer dependencies to indicate which versions of dotenv they are compatible with

[motdotla]

other modules should specify peer dependencies to indicate which versions of dotenv they are compatible with

I agree.

👍 for this PR