Ruby method to stub out ENV variables in Rspec.

gistfile1.txt

module EnvVar

  def set_env_var(name, value)
    ENV.stub(:[])
    ENV.stub(:[]).with(name).and_return(value)
  end

end

Have you try these ways:

stub_const('ENV', ENV.to_hash.merge('HOST' => 'http://sample.host'))

stub_const('ENV', 'HOST' => 'www.aaa.com')

@aldrienht Try this:

allow(ENV).to receive(:[]).with(name, second_param).and_return(value)

The climate_control gem is great for this use case, if you only need to support Ruby >= 2.5.

The stub_env or rspec-stubbed_env gems provide this functionality for both older and newer rubies.

I'm doing this: https://gist.github.com/henrik/8f4a9fc07e42a3a410a1049af2631bd9