UseFieldNameByDefault resulting in incorrect Field Name

[tomaszbk]

given these config:

type Config struct {
	BACKEND_URL   string `envDefault:"localhost:8000"`
}

and using:
opts := env.Options{UseFieldNameByDefault: true}
My app crashes because it cant find the env var BACKENDURL. I think the underscore should be kept given that it is the convention for writing env vars

[caarlos0]

you're correct that that is the convention for environment variable names, but it's not the convention for struct fields.

If you do instead:

type Config struct {
	BackendURL   string `envDefault:"localhost:8000"`
}

it'll get the name you expect.

I just pushed some documentation improvements around that, and a test to show how it works:

• a3551ca
• 1e2d9e1