@tsl0922 test cases provided in this PR

Sure would be nice to see this working. I'd like to be able to use empty environment variables.

Can someone restart the build please? Tests passed for me locally.

@sagikazarmark you can do a force push to trigger it.

Ping

Any ETA on this being merged (or rejected)? Looks like @tsl0922 reviewed this as #429, but then it stalled when it was resubmitted.

@bep @andrewstuart can you help us out here?

So my main concern here is that this has the potential to be considered a breaking change if are using empty environment variables in place of unsetting.

I'd be a lot more comfortable merging this if it was behind a default-off option.

So my main concern here is that this has the potential to be considered a breaking change if are using empty environment variables in place of unsetting.

On one side, I think the map lookups follow the v, ok := pattern, which would be similar, but I agree -- we cannot change this as the default behavior. That this is OS env vars, something "invisible", will create some very subtle bugs around. But an option (default off) would be good.

@andrewstuart @bep Thanks for your comments.

I added an AllowEmptyEnv method with tests and some documentation in the readme. By default this feature is turned off.

Breaking tests seem to be unrelated