Background:

We have a separate testing repo for OpenFeature's cloud native reference implementation flagd, as we utilize this for testing multiple SDKs in different languages utilizing gherkin/cucumber and testcontainers.

Issue:

We realized while implementing part of those tests, that the rust implementation of cucumber does not allow spaces in the row headers for examples. The substituion will fail, and the placeholder will not be replaced as expected. See following example with <targeting key>. This is already used for java, js, python and go implementation.

  @fractional
  Scenario Outline: Fractional operator shorthand
    Given a String-flag with key "fractional-flag-shorthand" and a default value "fallback"
    And a context containing a targeting key with value "<targeting key>"
    When the flag was evaluated with details
    Then the resolved details value should be "<value>"
    Examples:
      | targeting key    | value |
      | jon@company.com  | heads |
      | jane@company.com | tails |

https://github.com/open-feature/flagd-testbed/blob/9b73b3a95cd9e0885937d244b118713b26374b1d/gherkin/targeting.feature#L38-L47

Remark:

I found now documentation stating how a header should look like, and if our header definition might be off. Might be that this is missing some documentation, or this might be indeed a bug.

Thank you for the time and the great effort!