Feature: When an unknown formatter is used Scenario: Unknown formatter is used When I run "behave -f unknown1" Then it should fail with: """ behave: error: format=unknown1 is unknown """ Scenario: Unknown formatter is used together with another formatter When I run "behave -f plain -f unknown1" Then it should fail with: """ behave: error: format=unknown1 is unknown """ Scenario: Two unknown formatters are used When I run "behave -f plain -f unknown1 -f tags -f unknown2" Then it should fail with: """ behave: error: format=unknown1, unknown2 is unknown """